1. Introduction
Natural products are chemical compounds produced by living organisms. When extracted from their natural sources, often, these compounds are present as complex mixtures, necessitating separation for accurate structural identification. The isolation of a natural product may involve obtaining sufficient quantities of a pure compound for derivatization, biological testing, and potentially for potential commercial use. Alternatively, it may refer to isolating only analytical quantities for the purpose of identification and quantification within biological tissues.
In the latter case, gas chromatography–mass spectrometry (GC/MS) is commonly employed. This technique allows for the screening of biological tissues and fluids for known compounds, supported by existing mass spectral databases. In contrast, the former scenario—particularly when novel compounds are involved—requires a broader range of analytical tools. These may include nuclear magnetic resonance (NMR) spectroscopic techniques, single-crystal X-ray diffraction, and elemental analysis to complement mass spectrometry.
In recent years, extensive chemical profiling of essential oils of plants has been conducted, including going down to the level of distinguishing metabolites in essential oils of different phenotypes of the same species [1], often relying solely on GC/MS. This is especially prevalent when evaluating plant materials for potential health benefits or pharmaceutical properties. However, these studies frequently do not distinguish whether the detected compounds are endogenous metabolites or xenobiotics—foreign substances introduced into the organism.
On the one hand, this lack of differentiation allows for an unbiased assessment of anthropogenic xenobiotics across ecosystems and can supplement targeted environmental monitoring efforts. On the other hand, it would be helpful, if specific constituents are realized as xenobiotics rather than metabolites of the plant early on, so that, if xenobiotics, they may be disregarded as contributing to potential health effects of extracts in general of that particular plant species. A notable example is the isolation of phthalates from numerous plant species, reported as natural constituents without clarification of their likely anthropogenic origin [2] in most cases [3].
2. Methodology
In my time as reviewer of manuscripts on natural product isolation, time and again, I came across constituent compounds that appeared unlikely to be genuine natural metabolites. These include highly strained compounds such as cubanes, fluorinated cyclopropanes and boranes. Also, silane and siloxanes were frequently on the list of detected compounds. This led to a search utilizing the keywords “silane”, “silicone” and “siloxane” in combination with “natural product isolation” in the databases Scopus®, Web of Science® and SciFinder®. Subsequently, database searches were conducted using the most common substructures identified in the initial search—such as cyclosiloxanes of varying ring sizes, open-chain siloxanes, and silyl-substituted aromatics—employing a structural editor. The search results were further refined by incorporating the term “occurrence” and limiting the timeframe to the years 2009-2021. The pertinent manuscripts were acquired utilizing the resources of the library of the United Arab Emirates University, where not directly available online.
In this communication, the commonly used abbreviation L is used for linear permethylated siloxanes 9-13 (Figure 2) and D for cyclic permethylated siloxanes such as 4-8 (Figure 1) with numbers associated with these labels showing the number of -(CH3)2SiO- repeat units, resulting in decamethyltetrasiloxane (9) being L4 and octamethyltetracyclosiloxane (5) being D4.
3. Results and Discussion
3.1. Siloxanes and Alkyl- and Arylsilanes—Characteristics, Uses, and Toxicity
Three main groups make up the organosilicon compounds used in the industry: polydimethyl siloxane (PDMS, 14, Figure 3) which account for 80%, followed by low-weight methyl siloxanes (12%), with the rest being functionalized siloxanes [7] [8]. Due to their low surface tension, high thermal stability and lubricating properties (Table 1), poly-siloxanes are widely used in many products and applications such as household products, construction materials, in electronics, energy, transportation and textiles . The total worldwide production of poly-siloxanes was 2 million tons in 2002, of which 34% were used in North America, 33% in Western Europe and 28% in Asia [9] [10]. In 2013, the annual global sales of polysiloxanes increased to 2.12 million tons [11], including 470,000 tons in the United States and 800,000 tons in China. In 2019, global sales of polysiloxanes were 6.75 million tons , of which 4.5 million tons of polysiloxanes were produced in China, accounting for 2/3 of their global production . In 2020, the world production of all silicones amounted to 8 million tons [13]. Apart from the mostly permethylated siloxanes, there are siloxanes that possess more complicated organic residues . Some of these are used for special purpose materials [15] (Table 1). In 2002, organomodified siloxanes themselves constituted approximately 15% of the total silicone market, which was worth approximately 5 billion Euros . Then, there are alkyl- and arylsilanes, compounds in which Si-C bonds and not Si-O bonds are the compounds’ defining bonds. These are often used as precursors of products rather than as components of products. These can include halosilanes, aminosilanes, epoxysilanes, vinylsilanes and mercaptosilanes, very often used to link material building blocks [16].
Nevertheless, it must be noted that siloxanes degrade in the natural environment, mostly through hydrolysis and final oxidation of silicon to finally give silica. Reported half-lives in water are 16.7 days (d) for D4 (5, water solubility around 51 µg/L) at pH 7 and 12˚C in freshwater, and 2.9 d at pH 8 and 9˚C in marine water, 73.4 d for D5 (6, water solubility 17 µg/l at 23˚C), > 1 year for D6 (7, water solubility 5.13 µg/l at 25˚C), the latter two in freshwater at pH7 and 25˚C. Half lives in the atmosphere are given as 6.9 - 16.9 d for D4 (5), 6.2 - 11.0 d for D5 (6), 5.7 - 8.9 d for D6 (7), and 8.7 - 30.9 d for hexamethylcyclotrisiloxane (D3, 4) [45]-[48].
There has been targeted research of the occurrence of siloxanes in biota such as in the Crucian carp (Carassius auratus) around a siloxane producing plant , in archived German fish samples covering a period of two decades , and in the planktonic crustacean Daphnia magna . In the case of the crucian carp, 7 carp specimen each were collected from 7 sites along a river near a methylsiloxane producing plant in Liaoning Province, Northeast China. Concentrations of 6.5 - 18 ng/g D4 (5), 12 - 25 ng/g D5 (6), 5.0 - 13 ng/g D6 (7), 1.5 - 41 ng/g D7 (8), 0.58 - 2.0 ng/g L4 (10), 0.66 - 0.93 ng/g L5 (9), 0.45 - 1.0 ng/g L6 (11) were measured in the back muscle tissue of the fish . Only for D4 (5) an appreciable bioaccumulation potential was observed in the fish. Archived German fish samples partially showed higher siloxane contents with samples from a Saar river sampling at Güdingen (downstream the French-German border) of 1997 exhibiting 91 ng/g (ww) D4 (5), 6640 ng/g (ww) D5 (6) and 63 ng/g ww D6 (7) . In the third study, D4-D6 had been found in palm oil mill effluent, with D4 being detected at 0.0148 - 0.0357 mg/L, and the crustacean Daphnia magna was used for toxicity identification evaluation (TIE) tests upon being exposed to the effluent . In all 3 studies [41] [49] [50], it was made clear that the siloxanes detected were of anthropogenic origin.
While especially the high molecular weight silicones (siloxanes), often also used in medical applications are deemed little toxic to humans [51], at high doses, it has been found that volatile methylated silicones can affect animals’ reproductive and endocrine systems [52] [53], are carcinogenic, where especially D5 was shown to increase the incidence of the uterine adenocarcinoma in female rats [54], and harm the respiratory tract [13] [55]. Indeed, safety concerns increase with a decrease in size of the siloxanes, so that the greatest concern rests with smaller sized molecules such as the linear and cyclic siloxanes shown in Figure 1 and Figure 2 as low molecular weight silicones are more volatile, can change the structure of lipid bilayers by fluidization or even the extraction of lipids [56] [57] leading to irreversible damage of the stratum corneum [58] and can weaken cell membranes . In general, the vapor pressures of the linear siloxanes and the cyclic siloxanes are appreciable (Table 2). Low molecular weight silicones can accumulate in the organism, and can have a long-term effect on organs [59]. Volatile siloxanes can reach the lungs and hydrolyze. It must be noted that silica itself is not without its toxicity—direct inhalation of silica can lead to silicosis—where the degree of chemical interaction between silica particles and biomolecules, membranes, and cell systems may be determined by their surface, namely by the positioning of silanol (Si-OH) functions on the surface [60].
In comparison to siloxanes (silicones), silanes are much less common constituents in final products as silanes are inherently less stable than siloxanes. More often, compounds such as 1,2-bis(trimethylsilyl)benzene (2) are used as chemical starting materials. Thus, 1,2-bis(trimethylsilyl)benzene (2) itself is used as a precursor to benzyne and in the construction of luminescent π-conjugated materials [62]. 1,4-Bis(trimethylsilyl)benzene (3) has been forwarded as an additive in batteries with high performance solid-state electrolytes [63] and in semi-conducting devices [64]. It also has been used as a precursor for developing silicon carbide coating using plasma-assisted chemical vapor deposition (CVD) process [65]. There are fewer studies on hazards aryl- and alkylsilanes pose. It must be noted that aryl- and alkylsilanes for the most part are highly flammable [66]. They are also strong irritants to skin , eyes [67] [68] and the respiratory system . Many of the aryl- and alkylsilanes can have long lasting harmful effects to aquatic life [69].
3.2. Siloxanes and Arylsilanes Isolated from the Essential Oil of Plants and from Other Organisms
There have been reports of silylated compounds isolated from plants and other organisms (Table 3-5), where the authors have not commented on whether these compounds constitute actual phytochemicals/metabolites of natural origin, anthropogenic contaminants deposited on the plant material before collection or contamination stemming from the GC/MS analysis itself. Beneficial properties, e.g. antimicrobial properties, were ascribed to some of the silylated components within isolated essential plant oils as would typically be done for selected secondary plant metabolites exhibiting those traits, with the unspoken perspective that the silylated compounds necessarily belong to the metabolites produced by the plant or microorganism itself. These silylated compounds can be broken down into three main categories: a) small per-methylated cyclosiloxanes; b) open chain per-methylated siloxanes; and c) silylated aromatic compounds. In addition, there is a set of miscellaneous silylated compounds such as silylated cycloheptatrienones. There are examples of silylated compounds that have been reported to have been isolated that are rather instable such as structures that exhibit Si-H moieties, where the identity of the compounds may be in doubt.
Other non-permethylated cyclic siloxanes have been isolated from organisms such as the two mono-phenylated cyclosiloxanes nonamethylphenylcyclopentasiloxane (19) and heptamethylphenylcyclotetrasiloxane (20) from the leaves of the green amaranth (Amaranthus viridis Linn.) (Figure 5). The leaf extracts held a number of other siloxanes such as D6 (7) and D7 (8) . Other structures have not been unequivocally defined and/or exhibit Si-H bonds. Such an example is 1.3.5.7-tetraethyl-1-ethylbutoxysiloxycyclotetrasiloxane (21) [91] (Figure 6).
The isolation of linear permethylated siloxanes from plants and other organisms have been reported less frequently than that of permethylated cyclosiloxanes. Nevertheless, isolation of octamethyl-trisiloxane (22) , decamethyltetrasiloxane (10) [78] [85] [86] [112], dodecamethyl-pentasiloxane (9) , tetradecamethyl-hexasiloxane (11) , hexadecamethyl-heptasiloxane (12) [81], and octadecamethyl-octasiloxane (13) [113] is known. A number of papers have appeared where the names of non-permethylated linear siloxanes have been forwarded leading to structures such as compounds 23 and 24 [80] [96] [101] shown in Figure 7, all with a Si-H group at both termini. Some of these, however, may have been mistakenly labelled and may have meant to be permethylated cyclosiloxanes.
A number of tert-butyldimethylsilyl (TMDMS-) substituted compounds have been isolated from plants (Figure 11), including O-tert-butyldimethylsilyl substituted alcohols and acids and N-tert-butyldimethylsilyl substituted amjnes. Typical examples are 2-chloro-6-fluorobenzyl alcohol tert-butyl dimethyl silyl ether (38) from the fern Pteridium aquilinum (L.) [114], benzenepropanoic acid tert-butyldimethylsilyl ester (37) from Karchikai (Momordica cymbalaria) [74], 2-[(tert-butyldimethylsilyl)oxy]-1-isopropyl-4-methyl-benzene (39) from the essential of the stem bark of Blighia unijugata, a flowering plant in the soapberry family [86], as well as N-(tert-butyldimethylsilyl)-1,2-benzisothiazol-3-amine (36) from the seeds of the knicker nut Caesalpinia bonducella [79] and volatiles of fermented elephant foot yam roots and tubers [98], and 3-chloropropane-1,2-diol bis(tert-butyldimethylsilyl) ether (40) from the roasted seed oil of Camellia oleifera [90], 36 and 40 having been isolated from processed plant material [90,98]. It must be noted that 1,2-benzisothiazol-3-amine itself is utilized in the synthesis of agrochemicals [117]. Tert-butyldimethylsiloxy compounds are typically seen as hydroxy-protected molecules, in which the tert-butyldimethylsilyl (TBDMS) group serves as a protective group of an alcoholic or phenolic OH group [118]. It is less often used for the protection of a carboxylic acid function [119]. Compared to the trimethylsilyl (TMS) group, the TBDMS group is less susceptible to hydrolytic deprotection. Silyloxy groups in general can be deprotected facilely with fluoride anion, e.g., with the reagent tetrabutylammonium fluoride (Bu4NF). Nevertheless, as tert-butylsilylating agents such as tert-butyldimethylsilyl chloride are relatively expensive, O-tert-butylsilyl functions as protective groups are usually only found in small scale syntheses and siloxanes with tert-butyldimethylsiloxy groups in commercial products are rare indeed.
Directly C-silylated aromatic compounds have also been isolated from plants frequently. These include especially 1,2-bis(trimethylsilyl)benzene (2) [72]-[75] [77]-[81] [84]-[86] [122]-[128], 1,3-bis(trimethylsilyl)benzene (1) [83] [86] [121], and 1,4-bis(trimethylsilylbenzene (3) [72] [74] [79] [85] [112] [124] (Figure 1) Where bis(trimethylsilyl)benzenes 1-3 have been extracted from a natural source, oftentimes other siloxanes were found, too. Typical examples are the extraction of 2 from the medical plant Abrus precatorius (jequirity bean/rosary pea, Faboideae), where hexamethylcyclohexatrisiloxane (4) was also found . 1,4-Bis(trimethylsilyl)benzene (3) is utilized industrially as a silicon-containing precursor in chemical vapor deposition (CVD) processes to make thin films of silicon-based materials like silicon oxide, nitride, or carbide. 1,2-Bis(trimethylsilyl)benzene (2) is a key starting material for the synthesis of efficient benzyne precursors and certain luminescent π-conjugated materials [60]. However, both compounds are not produced in large amounts industrially, and for the most part, however, they are not constituents of consumer products.
Interestingly, 3,5-bis(trimethylsilyl)cycloheptatrienone [3,5-bis(trimethylsilyl)tropone] (41) (Figure 12) is another product that purportedly has been found in a number of plants, such as in Amomum nilgiricum (Zingiberaceae) [129], Dillenia scabrella (Dilleniaceae) [78], Boerhavia diffusa (Nyctaginaceae) [130], and the common guava (Psidium guajava) [131]. Now, there are no obvious large-scale applications or large scale industrial outputs of 3,5-bis(trimethylsilyl)cycloheptatrienone (41). In many scientific contributions on the isolation of 41, only the GC trace is shown, where the compound has been identified through a database by its molecular mass and retention time on the GC column used. Only in one case is the fragmentation pattern of the compound shown. There are instances where the quality of match of the obtained analytical data of the compound against existing mass spectral databases is relatively low (see below).
A further compound that is produced and used industrially in large amounts is silicic acid diethyl bis(trimethylsilyl) ester (49), where uses include surface treatments, coatings, and as a precursor in the production of other organosilicon compounds. 49 has been found in Karchikai vine (Momordica cymbalaria Hook. F.) [74] and in knicker nut (Caesalpinia bonducella) [79].
Looking at silylated inorganic compounds isolated from plants, derivatives of arsenous acid and arsenic trioxide stand out (Figure 15). While dimethylarsinic acid (cacodylic acid, 50) and its sodium salt are known herbicide, the anhydride form of arsenous acid, arsenic trioxide (51), is used as a herbicide, pesticide, and rodenticide [134]. Arsenous acid tris(trimethylsilyl)ester (52) and its tris(tertbutyldimethylsilyl) derivative 53 are usually only utilized as silylating reagent in organic synthesis. Although the oxygen of siloxanes can coordinate with electrophiles E+, it would be unlikely that arsenic trioxide would react with siloxanes or with degradation products of the Zebron-5MS column (5%-phenylmethylpolysiloxane) that was used in the separation of the extracts, especially as there is no source of the tert-butyldimethylsilyl group in evidence. Therefore, 52 and 53 isolated from black jack (Bidens pilosa) [80], from fermented elephant foot yam roots and tubers (Amorphophallus paeoniifolius) [132] and from Karchikai-vine (Momordica cymbalaria Hook. F.) [74] may be of different origin.
Additional silylated compounds that have been isolated from plants, but are not discussed further in the text can be seen in Figures 19-21.
3.3. Potential Sources of Siloxanes and Arylsilanes Isolated from the Essential Oil of Plants and from Other Organisms
The origin of siloxanes and arylsilanes in extracts from natural sources can be manifold. It is notable that oftentimes more than one type of silicon containing compound was isolated in different studies. Thus, Mostafa et al. [113] found 3 different siloxanes in the methanolic leaf extract of the olive (Olea europea), octamethylcyclotetrasiloxane (D4, 5), decamethylcyclopentasiloxane (D5, 6), and octadecamethyloctasiloxane (octasiloxane, L8, 13), which made up 14.7% of the identifiable components of the extract. Thenmozhi et al. [79] isolated 10 different silyl-containing compounds from the seed kernels of the knicker nut (Caesalpinia bonducella). The following is a discussion of possible sources of silyl-containing compounds from natural sources.
a) Targeted silylation of samples before injection of the samples for GC-MS chromatographic analysis
Sometimes, the GC separation of very polar compounds during GC-MS spectroscopic analysis requires TMS derivatization [138] [139]. Thus, Penduka et al. have silylated the samples before GC/MS analysis utilizing N–methyl–N–trimethylsilyltrifluoroacetamide (54, MSTFA) (pyridine/dichloromethane) (Figure 16). This explains the formation of such products as 1-trimethylsilyl-2-piperidinecarboxylic acid trimethylsilyl ester (55), 4-methyl-2-trimethylsilyloxyacetophenone (42), and 5-methyl-2-trimethylsilyloxyacetophenone (43), where these products may well not have been silylated in the original extract as well as trimethyl[4-(1-methyl-1-methoxyethyl)phenoxy]silane (33), trimethyl-(4-tert.-butylphenoxy)silane (35), silicic acid diethyl bis(trimethylsilyl) ester (49), and perhaps of methyltris(trimethylsiloxy)silane (31). This is also indicated by the authors. In addition, there is 1-dimethyl(phenyl)silyloxypentane (56) which does not stem from MSTFA treatment. Directly silylated arenes such as N,N-dimethyl-4-nitroso-3-(trimethylsilyl)aniline (57), N-[4-(trimethylsilyl)phenyl]acetamide (57) and 1,2-bis(trimethylsilyl)benzene (2) do not stem from MSTFA treatment, either. Direct C-silylation of arenes is still very rare, and 1,2-bis(dimethylsilyl)benzene (2) is still best synthesized from 1,2-dibromobenzene using Rieke-magnesium [60]. Interestingly, Penduka et al. identified the triterpenols lanosterol (59) and 9,19-cyclolanost-24-en-3β-ol (60) (Figure 17) in the extracts after treatment with MSTFA as the alcohols themselves and not as their silyl ethers. In none of the other cited studies did the authors note that a silylation of the mixed plant extract had been carried out prior to GC/MS analysis.
There are 4 basic sources of siloxanes entering the system in the gas chromatographic separation: the column itself, injector liners, septa and vial caps. In the case of a 100% dimethylpolysiloxane SE-30 column, bleeding does generate siloxanes that convert partially to D3 and in EI-mode give m/z 207 as the top peak [140], so that the presence of a peak with m/z 207 can be indicative of column bleeding [141]. Other ion peaks can be found at m/z 73, 133, 193, 267, 281, 355 and 429, where D4 has its top peak at m/z 281 [142], D5 at m/z 355 [143], and D6 at m/z 429 [144]. Analytes can also damage columns. Thus, fluorotrimethylsilane (61) (Figure 18) which is used as a fluorinating agent has been isolated from the volatiles of fermented honeyberry (Lonicera edulis). It is easily hydrolyzed, so that it would be likely that the compound is produced in the column in the presence of fluoride anion. The reaction would be equivalent to a fluoride induced desilylation of a trimethylsilyl ether, which can be achieved by tetrabutylammonium fluoride (TBAF). Fluoride containing samples could also potentially damage SE-30 columns for gas chromatography. Also, septa very often incorporate silicones which can be released upon interaction with organic solvents [145]. This happens especially during re-use of septa and vial caps. Also, valves and solvents can be sources of silicones and silanes.
c) Anthropogenic sources of silyl-containing compounds on plants and other organisms
The human driven emission of siloxanes into the environment has been mentioned in the introduction and is subject of a larger number of publications [8] [9] [13] [146]. The presence of typically used siloxanes in plants such as permethylated cyclosiloxanes D3-D8 and linear permethylated siloxanes L3-L8 may often be attributed to anthropogenic pollution. Even under ideal conditions, identifying the source of a specific contaminant or determining whether a compound is a true plant-derived metabolite or merely a contaminant is extremely challenging. Therefore, when uncertainty exists, authors should explicitly acknowledge it rather than present a silicon-containing compound as a natural metabolite. This is especially true when plant components are screened for their biological properties to understand the medicinal value of the plant itself. Thus, 4-methyl-2-trimethylsilyloxy-acetophenone (42) and tert-butyl-(5-isopropyl-2-methylphenoxy)dimethylsilane (39) have been published to have antimicrobial properties [79] [80]. Overall, it must also be noted that the ubiquity of siloxanes in the environment may have adverse effects on human health [147].
d) misidentification through insufficient matching of mass data with mass spectral databases
One needs to take care when identifying organic compounds from mixtures solely by GC-MS. Where retention indices are often used to corroborate spectral matches, variations in experimental conditions can cause discrepancies between experimental and database RIs, leading to false positives. A study highlighted that even with a match score of 98%, there remains a significant probability of misidentification, particularly when the match score is below 80%. As an example, the quality of the match for 1,2-bis(trimethylsilyl)benzene (2) as a volatile constituent in the methanolic extract of Rumex nervosus meal was reported as 50% [84]. Employing algorithms that consider the difference between the first and second highest spectral similarity scores can reduce false positives. This approach has been shown to achieve higher true positive rates compared to conventional methods. Using multiple, curated databases and incorporating MS/MS data can enhance the reliability of compound identification [148]. Tools like MS-FINDER facilitate this by integrating various databases and in silico fragmentation data [149].
It is important to note, however, that no silicon-containing natural secondary plant metabolite has been unequivocally identified—meaning that no novel silicon-containing structure that has not yet been synthesized industrially or in a research laboratory setting has been isolated from a plant or other organism and structurally characterized using NMR, IR, and MS spectroscopy, nor have feeding experiments with labeled precursors been conducted that clearly demonstrate the incorporation of silicon into organic structures in a defined manner by the organism. Thus, while sulfur containing amino acids such as cysteine, cysteine and methionine as well as selenoamino acids such as selenocysteine [168] are known and arsinothricin as a non-proteinogenic arsenoamino acid has been isolated from the rice rhizosphere bacterium Burkholderia gladioli strain GSRB05 fed with medium containing arsenite (AsIII) [169] [170], no such silicon containing amino acid has been found to date. Si much prefers to bond with oxygen (O) than with carbon (C). A Si-C bond (~318 kJ/mol) is weaker than a comparable C-C bond (~348 kJ/mol (stronger)), while a Si-O bond (~452 kJ/mol) is significantly stronger than a comparable C-O bond (~358 kJ/mol), making the Si-O bond extremely stable, while Si–C bonds are more reactive than C-C bonds, particularly to hydrolysis, reactions that ultimately lead to silica, making silicon containing metabolites, should they to exist, very elusive species.
Name of isolated compound |
Latin name of the organism |
Common name of the organism |
Fraction in which the compound was isolated from |
Type of analysis |
Location |
Reference |
Hexamethylcyclotrisiloxane (D3,4) |
Juglans regia |
Walnut |
green husks |
GC/MS |
West Anatolia, Turkey |
D. Keskin et al., 2012 [70] |
Hexamethylcyclotrisiloxane (D3,4) |
Phyllostachys heterocycla (Phyllostachys edulis) |
Bamboo |
biomass |
GC/MS |
China |
Q.Z. Ma et al., 2010 [71] |
Hexamethylcyclotrisiloxane (D3,4) |
Vernonia amygdalina |
Bitter leaf |
leaf extract |
GC/MS |
Elizade University, Ilara‐mokin, Ondo state, Nigeria |
O.S. Omojokun et al., 2019 [72] |
Hexamethylcyclotrisiloxane (D3,4) |
Sesamum indicum L |
Sesame (Pedaliaceae) |
Seeds (light petroleum ether extract) |
GC/MS |
different states of India |
R. Tyagi and V. Sharma, 2014 [73] |
Hexamethylcyclotrisiloxane (D3,4) |
Momordica cymbalaria Hook. F. |
Karchikai - Vine (Cucurbitaceae) |
methanolic extract of the tuber |
GC/MS |
Sattur Taluk, Virudhunager District, Tamil Nadu, India |
M. Gurusamy et al., 2019 [74] |
Hexamethylcyclotrisiloxane (D3,4) |
Gymnopilus spectabilis |
Mushroom |
methanolic extract |
GC/MS |
southern Western Ghats, India |
V. Ragupathi et al., 2018 [75] |
Hexamethylcyclotrisiloxane (D3,4) |
Bacillus subtilis strain Bs-1 |
Hay bacillus (Gram-positive bacterium) |
Volatile organic compounds |
GC/MS |
Laboratory in China |
H. Cao et al., 2019 [76] |
Hexamethylcyclotrisiloxane (D3,4) |
Punica granatum |
Pomegranate |
fruit rind |
|
Supermarket bought, Vellore Institute of Technology, Vellore campus |
A. Prakash and V. Suneetha, 2014 [77] |
Hexamethylcyclotrisiloxane (D3,4) |
Dillenia scabrella |
(Deciduous tree) |
leaf (methanolic extract) |
GC/MS |
West Garo Hills, District of Meghalaya, North East India |
K. Momin and S.C. Thomas, 2020 [78] |
Hexamethylcyclotrisiloxane (D3,4) |
Caesalpinia bonducella |
Knicker nut |
seed kernels (ethyl acetate extract) |
GC/MS |
Kolli hills, Nammakkal District of Tamil Nadu, India |
A. Thenmozhi et al. 2020 [79] |
Hexamethylcyclotrisiloxane (D3,4) |
Bidens pilosa |
black-jack (Asteraceae) |
leaf (aqueous ethanolic extract) |
GC/MS |
University of Fort Hare farm, South Africa |
A.B. Falowo et al., 2017 [80] |
Hexamethylcyclotrisiloxane (D3,4) |
Dillenia scabrella |
(deciduous tree) |
leaf (ethanolic – ethyl acetate extract) |
GC/MS |
West Garo Hills, District of Meghalaya, North East India |
K. Momin and S.C. Thomas, 2020 [78] |
Hexamethylcyclotrisiloxane (D3,4) |
Dillenia scabrella |
(deciduous tree) |
bark (ethanolic – ethyl acetate extract) |
GC/MS |
West Garo Hills, District of Meghalaya, North East India |
K. Momin and S.C. Thomas, 2020 [78] |
Hexamethylcyclotrisiloxane (D3,4) |
Cinnamomum camphora |
camphor tree (evergreen tree) |
leaf (methanolic extract) |
GC/MS |
Central South University of Forestry and Technology, P. R. China |
N.-C. Li et al., 2015 [81] |
Hexamethylcyclotrisiloxane (D3,4) |
Andrographis echioides |
False water willow (Acanthaceae) |
Leaf |
GC/MS |
Sengippatti, Tamil Nadu, India |
K. Jeevanantham and A. Zahir Hussain, 2018 [82] |
Hexamethylcyclotrisiloxane (D3,4) |
Abrus precatorius |
jequirity bean/rosary pea |
|
GC/MS |
|
Hussain and Kumaresan, 2014 [83] |
Hexamethylcyclotrisiloxane (D3,4) |
Rumex nervosus |
Nerveleaf dock |
Methanolic leaf extract Extraction was performed at King Saud University |
GC/MS |
Bait,
Al-Radmah district, Ibb governorate, Yemen |
M.M. Azzam et al., 2020 [84] |
Hexamethylcyclotrisiloxane (D3,4) |
Gardicinia kola |
Bitter kola |
n-Hexane extracts of seeds |
GC/MS |
Southwestern Nigeria |
Penduka et al., 2014 [85] |
Hexamethylcyclotrisiloxane (D3,4) |
Blighia unijugata Baker |
Triangle-tops evergreen tree (Sapindaceae) |
essential oil (stem and flowers) |
GC/MS |
University of Ibadan, Nigeria |
D.O. Moronkola et al., 2017 [86] |
Octamethylcyclotetrasiloxane (D4,5) |
Phyllostachys heterocycla (Phyllostachys edulis) |
Bamboo |
Biomass |
GC/MS |
China |
Q.Z. Ma et al., 2010 [71] |
Octamethylcyclotetrasiloxane (D4,5) |
Drypetes hainanensis |
Putranjivaceae |
Leaf and branch |
GC/MS |
China |
P.H. Liu et al., 2013 [87] |
Octamethylcyclotetrasiloxane (D4,5) |
Pistia stratiotes |
Water lettuce (Araceae) |
Root exudates (hydroponic experiments – nutrients with different phosphorus content) |
GC/MS |
China |
J. Zhang et al. 2019 [88] |
Octamethylcyclotetrasiloxane (D4,5) |
Piper betle |
Betel (Piperaceae) |
Leaf |
GC/MS |
Nanjikkottai, Thanjavur Dt. Tamilnadu, India |
F.F.S. Beatrice and G. Santhi, 2017 [89] |
Octamethylcyclotetrasiloxane (D4,5) |
Bacillus subtilis strain Bs-1 |
Hay bacillus (Gram-positive bacterium) |
Volatile organic compounds |
GC/MS |
Laboratory in China |
H. Cao et al., 2019 [76] |
Octamethylcyclotetrasiloxane (D4,5) |
Dillenia scabrella |
(deciduous tree) |
leaf (methanolic extract) |
GC/MS |
West Garo Hills, District of Meghalaya, North East India |
K. Momin and S.C. Thomas, 2020 [78] |
Octamethylcyclotetrasiloxane (D4,5) |
Dillenia scabrella |
(deciduous tree) |
leaf (ethanolic – ethyl acetate extract) |
GC/MS |
West Garo Hills, District of Meghalaya, North East India |
K. Momin and S.C. Thomas, 2020 [78] |
Octamethylcyclotetrasiloxane (D4,5) |
Dillenia scabrella |
(deciduous tree) |
bark (methanolic extract) |
GC/MS |
West Garo Hills, District of Meghalaya, North East India |
K. Momin and S.C. Thomas, 2020 [78] |
Octamethylcyclotetrasiloxane (D4,5) |
Camellia oleifera Abel. |
Tea oil camellia |
seed (oil) |
GC/MS |
Zengcheng Teaching and Research Bases, South China Agricultural University, China |
J. He et al., 2021 [90] |
Decamethylcyclopentasiloxane (D5,6) |
Brassica oleraceae var. Botrytis |
Egyptian cauliflower |
leaves, stems (hydrodistillation) |
GC/MS |
Bayaad el Arab, Beni-Suef, Egypt |
M.S. Hifnawy et al., 2013 [91] |
Decamethylcyclopentasiloxane (D5,6) |
Hirsutella sinensis |
Caterpillar fungus (Ophiocordycipitaceae) |
|
GC/MS |
|
S. Yu et al., 2012 [92] |
Decamethylcyclopentasiloxane (D5,6) |
Elaeis guineensis |
Oil palm |
Palm leaf extract |
GC/MS |
Ughelli, Delta State, Nigeria |
P. Onakurhefe et al. 2019 [93] |
Decamethylcyclopentasiloxane (D5,6) |
Bacillus subtilis strain Bs-1 |
Hay bacillus (Gram-positive bacterium) |
Volatile organic compounds |
GC/MS |
Laboratory in China |
H. Cao et al., 2019 [76] |
Decamethylcyclopentasiloxane (D5,6) |
Artemisia vulgaris L. |
Mugwort |
Essential oil |
GC/MS |
Tangyin, Henan province, China |
Z. Jiang et al., 2019 [94] |
Decamethylcyclopentasiloxane (D5,6) |
Juglans regia |
walnut |
green husks |
GC/MS |
West Anatolia, Turkey |
D. Keskin et al., 2012 [70] |
Decamethylcyclopentasiloxane (D5,6) |
Drypetes hainanensis |
Putranjivaceae |
Leaf and branch |
GC/MS |
China |
P.H. Liu et al., 2013 [87] |
Decamethylcyclopentasiloxane (D5,6) |
Bacillus
atro-phaeus strain HAB-5 |
black-pigmented bacteria |
from healthy rhizophere of cotton plant |
GC/MS |
Xinjiang province, China |
M.J.N. Rajaofera et al., 2019 [95] |
Decamethylcyclopentasiloxane (D5,6) |
Nigrospora sphaerica |
endophytic filamentous fungus of Parthenium hysterophorous |
|
GC/MS |
Panjab University, Chandigarh, India |
I.B. Prasher and R.K. Dhanda, 2017 [96] |
Decamethylcyclopentasiloxane (D5,6) |
Pistia stratiotes |
Water lettuce (Araceae) |
Root exudates (hydroponic experiments – nutrients with different phosphorus content) |
GC/MS |
China |
J. Zhang et al. 2019 [88] |
Decamethylcyclopentasiloxane (D5,6) |
Polygonatum cirrhifolium (Wall.) Royle |
Solomon’s seal (flowering plant) (Asparagaceae) |
|
GC/MS |
Narkanda, Himachal Pradesh, India |
S.K. Singh and A. Patra, 2019 [97] |
Decamethylcyclopentasiloxane (D5,6) |
Brainea insignis (Hook.) J. Sm. |
Fern (Blechnaceae) |
Xylem caudex (stem) |
GC/MS |
China |
Y.N. Fan et al., 2008 [98] |
Decamethylcyclopentasiloxane (D5,6) |
Piper betle |
Betel (Piperaceae) |
Leaf |
GC/MS |
Nanjikkottai, Thanjavur Dt. Tamilnadu, India |
F.F.S. Beatrice and G. Santhi, 2017 [89] |
Decamethylcyclopentasiloxane (D5,6) |
Phyllostachys heterocycla (Phyllostachys edulis) |
bamboo |
biomass |
GC/MS |
China |
Q.Z. Ma et al., 2010 [71] |
Dodecamethylcyclohexasiloxane (D6,7) |
Brassica oleraceae var. Botrytis |
Egyptian cauliflower |
leaves, stems (hydrodistillation) |
GC/MS |
Bayaad el Arab, Beni-Suef, Egypt |
M.S. Hifnawy et al., 2013 [91] |
Dodecamethylcyclohexasiloxane (D6,7) |
Bacillus
atro-phaeus strain HAB-5 |
black-pigmented bacteria |
from healthy rhizophere of cotton plant |
GC/MS |
Xinjiang province, China |
M.J.N. Rajaofera et al., 2019 [95] |
Dodecamethylcyclohexasiloxane (D6,7) |
Streptomyces sp. strain ND7a |
marine bacterium isolated from a sponge |
|
GC/MS |
Ha Tien Sea, Kien Giang province, Vietnam |
T.V. Phuong et al., 2018 [99] |
Dodecamethylcyclohexasiloxane (D6,7) |
Brainea insignis (Hook.) J. Sm. |
Fern (Blechnaceae) |
Xylem caudex (stem) |
GC/MS |
China |
Y.N. Fan et al., 2008 [98] |
Dodecamethylcyclohexasiloxane (D6,7) |
Artemisia vulgaris L. |
Mugwort |
Essential oil |
GC/MS |
Tangyin, Henan province, China |
Z. Jiang et al., 2019 [94] |
Dodecamethylcyclohexasiloxane (D6,7) |
Nigrospora sphaerica |
endophytic filamentous fungus of Parthenium hysterophorous |
|
GC/MS |
Panjab University, Chandigarh, India |
I.B. Prasher and R.K. Dhanda, 2017 [96] |
Dodecamethylcyclohexasiloxane (D6,7) |
Rosa sterilis |
|
Volatile oil |
GC/MS |
China |
X.Q. Wu et al., 2014 [100] |
Dodecamethylcyclohexasiloxane (D6,7) |
Cymbidium faberi |
Orchid |
Volatiles (related to flower fragrance) |
GC/MS |
Dangyang, Hubei province, China |
Y. Zhou et al., 2018 [101] |
Dodecamethylcyclohexasiloxane (D6,7) |
Drypetes hainanensis |
Putranjivaceae |
Leaf and branch |
GC/MS |
China |
P.H. Liu et al., 2013 [87] |
Dodecamethylcyclohexasiloxane (D6,7) |
Polygonatum cirrhifolium (Wall.) Royle |
Solomon’s seal (flowering plant) (Asparagaceae) |
|
GC/MS |
Narkanda, Himachal Pradesh, India |
S.K. Singh and A. Patra, 2019 [97] |
Dodecamethylcyclohexasiloxane (D6,7) |
Hirsutella sinensis |
Caterpillar fungus (Ophiocordycipitaceae) |
|
GC/MS |
|
S. Yu et al., 2012 [92] |
Dodecamethylcyclohexasiloxane (D6,7) |
Syzygium cumini |
black plum |
Seed powder |
GC/MS |
Aurangabad city, Maharashtra, India |
A.H. Abdul Jaleel et al., 2014 [102] |
Dodecamethylcyclohexasiloxane (D6,7) |
Argemone ochroleuca Sweet |
Mexican poppy (Papaveraceae) |
Latex |
GC/MS |
Abha City, Aseer Region, Saudi Arabia |
M.M. Moustafa et al., 2013 [103] |
Dodecamethylcyclohexasiloxane (D6,7) |
Pistia stratiotes |
Water lettuce (Araceae) |
Root exudates (hydroponic experiments – nutrients with different phosphorus content) |
GC/MS |
China |
J. Zhang et al. 2019 [88] |
Dodecamethylcyclohexasiloxane (D6,7) |
Amaranthus viridis Linn. |
Green amaranth (Amaranthaceae) |
Leaf |
GC/MS |
Hyderabad, Telangana, India |
D.D. Suneetha et al., 2017 [104] |
Dodecamethylcyclohexasiloxane (D6,7) |
Piper betle |
Betel (Piperaceae) |
Leaf |
GC/MS |
Nanjikkottai, Thanjavur Dt. Tamilnadu, India |
F.F.S. Beatrice and G. Santhi, 2017 [89] |
Dodecamethylcyclohexasiloxane (D6,7) |
Lycium ruthenicum |
Russian ox thorn (Solanaceae) |
Volatile oil |
GC/MS |
China |
X. Zhao and K. Li, 2016 [105] |
Dodecamethylcyclohexasiloxane (D6,7) |
Bacillus subtilis strain Bs-1 |
Hay bacillus (Gram-positive bacterium) |
Volatile organic compounds |
GC/MS |
Laboratory in China |
H. Cao et al., 2019 [76] |
Dodecamethylcyclohexasiloxane (D6,7) |
Irpex lacteus |
White-rot fungus |
|
GC/MS |
Kasauli, Himachal Pradesh, India |
R. Chaudhary and A. Tripathy, 2015 [106] |
Dodecamethylcyclohexasiloxane (D6,7) |
Koelreuteria paniculata |
Golden rain tree (Sapindaceae) |
Leaves |
GC/MS |
Iran |
S. Ghahari et al., 2015 [107] |
Dodecamethylcyclohexasiloxane (D6,7) |
Linum usitatissimum |
Flax |
|
GC/MS |
India |
N. Kaur et al., 2017 [108] |
Tetradecamethylcycloheptasiloxane (D7,8) |
Brassica oleraceae var. Botrytis |
Egyptian cauliflower |
leaves, stems (hydrodistillation) |
GC/MS |
Bayaad el Arab, Beni-Suef, Egypt |
M.S. Hifnawy et al., 2013 [91] |
Tetradecamethylcycloheptasiloxane (D7,8) |
Bacillus cereus S1 |
Gram positive bacteria isolated from the surface of shrimps |
Filtrate |
GC/MS |
Egypt |
S.W.M. Hassan, 2016 [109] |
Tetradecamethylcycloheptasiloxane (D7,8) |
Streptomyces sp. strain ND7a |
marine bacterium isolated from a sponge |
|
GC/MS |
Ha Tien Sea, Kien Giang province, Vietnam |
T.V. Phuong et al., 2018 [99] |
Tetradecamethylcycloheptasiloxane (D7,8) |
Nigrospora sphaerica |
endophytic filamentous fungus of Parthenium hysterophorous |
|
GC/MS |
Panjab University, Chandigarh, India |
I.B. Prasher and R.K. Dhanda, 2017 [96] |
Tetradecamethylcycloheptasiloxane (D7,8) |
Syzygium cumini |
Black plum |
Seed powder |
GC/MS |
Aurangabad city, Maharashtra, India |
A.H. Abdul Jaleel et al., 2014 [102] |
Tetradecamethylcycloheptasiloxane (D7,8) |
Amaranthus viridis Linn. |
Green amaranth (Amaranthaceae) |
Leaf |
GC/MS |
Hyderabad, Telangana, India |
D.D. Suneetha et al., 2017 [104] |
Tetradecamethylcycloheptasiloxane (D7,8) |
Pistia stratiotes |
Water lettuce (Araceae) |
Root exudates (hydroponic experiments – nutrients with different phosphorus content) |
GC/MS |
China |
J. Zhang et al. 2019 [88] |
Tetradecamethylcycloheptasiloxane (D7,8) |
Brainea insignis (Hook.) J. Sm. |
Fern (Blechnaceae) |
Xylem caudex (stem) |
GC/MS |
China |
Y.N. Fan et al., 2008 [98] |
Tetradecamethylcycloheptasiloxane (D7,8) |
Polygonatum cirrhifolium (Wall.) Royle |
Solomon’s seal (flowering plant) (Asparagaceae) |
|
GC/MS |
Narkanda, Himachal Pradesh, India |
S.K. Singh and A. Patra, 2019 [97] |
Tetradecamethylcycloheptasiloxane (D7,8) |
Argemone ochroleuca Sweet |
Mexican poppy (Papaveraceae) |
Latex |
GC/MS |
Abha City, Aseer Region, Saudi Arabia |
M.M. Moustafa et al., 2013 [103] |
Tetradecamethylcycloheptasiloxane (D7,8) |
Piper betle |
Betel (Piperaceae) |
Leaf |
GC/MS |
Nanjikkottai, Thanjavur Dt. Tamilnadu, India |
F.F.S. Beatrice and G. Santhi, 2017 [89] |
Tetradecamethylcycloheptasiloxane (D7,8) |
Irpex lacteus |
White-rot fungus |
|
GC/MS |
Kasauli, Himachal Pradesh, India |
R. Chaudhary and A. Tripathy, 2015 [106] |
Tetradecamethylcycloheptasiloxane (D7,8) |
Dillenia scabrella |
(deciduous tree) |
leaf (ethanolic – ethyl acetate extract) |
GC/MS |
West Garo Hills, District of Meghalaya, North East India |
K. Momin and S.C. Thomas, 2020 [78] |
Hexadecamethylcyclooctasiloxane (D8,15) |
Bacillus
atro-phaeus strain HAB-5 |
Black-pigmented bacteria |
from healthy rhizophere of cotton plant |
GC/MS |
Xinjiang province, China |
M.J.N. Rajaofera et al., 2019 [95] |
Hexadecamethylcyclooctasiloxane (D8,15) |
Nigrospora sphaerica |
Endophytic filamentous fungus of Parthenium hysterophorous |
|
GC/MS |
Panjab University, Chandigarh, India |
I.B. Prasher and R.K. Dhanda, 2017 [96] |
Hexadecamethylcyclooctasiloxane (D8,15) |
Polygonatum cirrhifolium (Wall.) Royle |
Solomon’s seal (flowering plant) (Asparagaceae) |
|
GC/MS |
Narkanda, Himachal Pradesh, India |
S.K. Singh and A. Patra, 2019 [97] |
Hexadecamethylcyclooctasiloxane (D8,15) |
Cymbidium faberi |
Orchid |
Volatiles (related to flower fragrance) |
GC/MS |
Dangyang, Hubei province, China |
Y. Zhou et al., 2018 [101] |
Hexadecamethylcyclooctasiloxane (D8,15) |
Moschus moschiferus |
Musk of musk deer |
volatile components of mother tinctures |
GC/MS |
Russia |
Ya.F. Kopytko and N.S. Tsibulko, 2019 [110] |
Hexadecamethylcyclooctasiloxane (D8,15) |
Hemigraphis colorata (Hemigraphis alternate) |
Red ivy (Acanthaceae) |
Leaf and stem |
GC/MS |
Kerala, India |
L. Palakkal et al., 2019 [111] |
Hexadecamethylcyclooctasiloxane (D8,15) |
Syzygium cumini |
Black plum |
Seed powder |
GC/MS |
Aurangabad city, Maharashtra, India |
A.H. Abdul Jaleel et al., 2014 [102] |
Hexadecamethylcyclooctasiloxane (D8,15) |
Phyllostachys heterocycla (Phyllostachys edulis) |
Bamboo |
biomass |
GC/MS |
China |
Q.Z. Ma et al., 2010 [71] |
Hexadecamethylcyclooctasiloxane (D8,15) |
Bacillus cereus S1 |
Gram positive bacteria isolated from the surface of shrimps |
Filtrate |
GC/MS |
Egypt |
S.W.M. Hassan, 2016 [109] |
Octadecamethylcyclononasiloxane (D9,16) |
Bacillus
atro-phaeus strain HAB-5 |
black-pigmented bacteria |
from healthy rhizophere of cotton plant |
GC/MS |
Xinjiang province, China |
M.J.N. Rajaofera et al., 2019 [95] |
Octadecamethylcyclononasiloxane (D9,16) |
Rosa sterilis |
|
Volatile oil |
GC/MS |
China |
X.Q. Wu et al., 2014 [100] |
Octadecamethylcyclononasiloxane (D9,16) |
Amaranthus viridis Linn. |
Green amaranth (Amaranthaceae) |
Leaf |
GC/MS |
Hyderabad, Telangana, India |
D.D. Suneetha et al., 2017 [104] |
Octadecamethylcyclononasiloxane (D9,16) |
Brassica oleraceae var. Botrytis |
Egyptian cauliflower |
leaves, stems (hydrodistillation) |
GC/MS |
Bayaad el Arab, Beni-Suef, Egypt |
M.S. Hifnawy et al., 2013 [91] |
Octadecamethylcyclononasiloxane (D9,16) |
Nigrospora sphaerica |
endophytic filamentous fungus of Parthenium hysterophorous |
|
GC/MS |
Panjab University, Chandigarh, India |
I.B. Prasher and R.K. Dhanda, 2017 [96] |
Octadecamethylcyclononasiloxane (D9,16) |
Koelreuteria paniculata |
Golden rain tree (Sapindaceae) |
Leaves |
GC/MS |
Iran |
S. Ghahari et al., 2015 [107] |
Octadecamethylcyclononasiloxane (D9,16) |
Polygonatum cirrhifolium (Wall.) Royle |
Solomon’s seal (flowering plant) (Asparagaceae) |
|
GC/MS |
Narkanda, Himachal Pradesh, India |
S.K. Singh and A. Patra, 2019 [97] |
Octadecamethylcyclononasiloxane (D9,16) |
Bacillus cereus S1 |
Gram positive bacteria isolated from the surface of shrimps |
Filtrate |
GC/MS |
Egypt |
S.W.M. Hassan, 2016 [109] |
Octadecamethylcyclononasiloxane (D9,16) |
Piper betle |
Betel (Piperaceae) |
leaf |
GC/MS |
Nanjikkottai, Thanjavur Dt. Tamilnadu, India |
F.F.S. Beatrice and G. Santhi, 2017 [89] |
Eicosamethylcyclodecasiloxane (D10,17) |
Polygonatum cirrhifolium (Wall.) Royle |
Solomon’s seal (flowering plant) (Asparagaceae) |
|
GC/MS |
Narkanda, Himachal Pradesh, India |
S.K. Singh and A. Patra, 2019 [97] |
Eicosamethylcyclodecasiloxane (D10,17) |
Nigrospora sphaerica |
Endophytic filamentous fungus of Parthenium hysterophorous |
|
GC/MS |
Panjab University, Chandigarh, India |
I.B. Prasher and R.K. Dhanda, 2017 [96] |
Eicosamethylcyclodecasiloxane (D10,17) |
Rosa sterilis |
|
Volatile oil |
GC/MS |
China |
X.Q. Wu et al., 2014 [100] |
Tetracosamethylcyclododecasiloxane (D12,18) |
Brassica oleraceae var. Botrytis |
Egyptian cauliflower |
leaves, stems (hydrodistillation) |
GC/MS |
Bayaad el Arab, Beni-Suef, Egypt |
M.S. Hifnawy et al., 2013 [91] |
1.3.5.7-Tetraethyl-1- ethylbutoxysiloxycyclotetrasiloxane (21) |
Brassica oleraceae var. Botrytis |
Egyptian cauliflower |
leaves, stems (hydrodistillation) |
GC/MS |
Bayaad el Arab, Beni-Suef, Egypt |
M.S. Hifnawy et al., 2013 [91] |
Octamethyl-trisiloxane (22) |
Fritillaria pallidiflora |
Siberian fritillary |
root exudates |
|
|
Y. Wang et al., 2009 [112] |
Decamethyl-tetrasiloxane (10) |
Dillenia scabrella |
(deciduous tree) |
bark (methanolic extract) |
GC/MS |
West Garo Hills, District of Meghalaya, North East India |
K. Momin and S.C. Thomas, 2020 [78] |
Decamethyl-tetrasiloxane (10) |
Fritillaria pallidiflora |
Siberian fritillary |
root exudates |
|
|
Y. Wang et al., 2009 [112] |
Decamethyl-tetrasiloxane (10) |
Gardicinia kola |
Bitter kola |
n-Hexane extracts of seeds |
GC/MS |
Southwestern Nigeria |
Penduka et al., 2014 [85] |
Decamethyl-tetrasiloxane (10) |
Blighia unijugata Baker |
Triangle-tops evergreen tree (Sapindaceae) |
essential oil (flower) |
GC/MS |
University of Ibadan, Nigeria |
D.O. Moronkola et al., 2017 [86] |
Dodecamethylpentasiloxane (9) |
Brassica oleraceae var. Botrytis |
Egyptian cauliflower |
leaves, stems (hydrodistillation) |
GC/MS |
Bayaad el Arab, Beni-Suef, Egypt |
M.S. Hifnawy et al., 2013 [91] |
Tetradecamethylhexasiloxane (11) |
Brassica oleraceae var. Botrytis |
Egyptian cauliflower |
leaves, stems (hydrodistillation) |
GC/MS |
Bayaad el Arab, Beni-Suef, Egypt |
M.S. Hifnawy et al., 2013 [91] |
Hexadecamethylheptasiloxane (12) |
Brassica oleraceae var. Botrytis |
Egyptian cauliflower |
leaves, stems (hydrodistillation) |
GC/MS |
Bayaad el Arab, Beni-Suef, Egypt |
M.S. Hifnawy et al., 2013 [91] |
Hexadecamethylheptasiloxane (12) |
Piper betle |
Betel (Piperaceae) |
Leaf |
GC/MS |
Nanjikkottai, Thanjavur Dt. Tamilnadu, India |
F.F.S. Beatrice and G. Santhi, 2017 [89] |
Hexadecamethylheptasiloxane (12) |
Bacillus cereus S1 |
Gram positive bacteria isolated from the surface of shrimps |
Filtrate |
GC/MS |
Egypt |
S.W.M. Hassan, 2016 [109] |
Tetradecamethylheptasiloxane (23) |
Moringa oleifera |
drumstick tree |
leaf (aqueous ethanolic extract) |
GC/MS |
Moringa South Africa Ltd |
A.B. Falowo et al., 2017 [80] |
Tetradecamethylheptasiloxane (23) |
Bidens pilosa |
black-jack (Asteraceae) |
leaf (aqueous ethanolic extract) |
GC/MS |
University of Fort Hare farm, South Africa |
A.B. Falowo et al., 2017 [80] |
Hexadecamethyloctasiloxane (24) |
Cymbidium faberi |
orchid |
Volatiles (related to flower fragrance) |
GC/MS |
Dangyang, Hubei province, China |
Y. Zhou et al., 2018 [101] |
Hexadecamethyloctasiloxane (24) |
Nigrospora sphaerica |
endophytic filamentous fungus of Parthenium hysterophorous |
|
GC/MS |
Panjab University, Chandigarh, India |
I.B. Prasher and R.K. Dhanda, 2017 [96] |
Hexadecamethyloctasiloxane (24) |
Moringa oleifera |
drumstick tree |
leaf (aqueous ethanolic extract) |
GC/MS |
Moringa South Africa Ltd |
A.B. Falowo et al., 2017 [80] |
Hexadecamethyloctasiloxane (24) |
Bidens pilosa |
black-jack (Asteraceae) |
leaf (aqueous ethanolic extract) |
GC/MS |
University of Fort Hare farm, South Africa |
A.B. Falowo et al., 2017 [80] |
Dimethyl-[bis(tridecyloxy)]
silane (26) |
Polygonatum cirrhifolium (Wall.) Royle |
Solomon’s seal (flowering plant) (Asparagaceae) |
|
GC/MS |
Narkanda, Himachal Pradesh, India |
S.K. Singh and A. Patra, 2019 [97] |
Dimethyl(docosyloxy)-butoxysilane (27) |
Polygonatum cirrhifolium (Wall.) Royle |
Solomon’s seal (flowering plant) (Asparagaceae) |
|
GC/MS |
Narkanda, Himachal Pradesh, India |
S.K. Singh and A. Patra, 2019 [97] |
Diethylheptyloxyoctadecyloxy -silane (28) |
Polygonatum cirrhifolium (Wall.) Royle |
Solomon’s seal (flowering plant) (Asparagaceae) |
|
GC/MS |
Narkanda, Himachal Pradesh, India |
S.K. Singh and A. Patra, 2019 [97] |
Heptamethyl-phenyl-cyclotetrasiloxane (20) |
Amaranthus viridis Linn. |
Green amaranth (Amaranthaceae) |
Leaf |
GC/MS |
Hyderabad, Telangana, India |
D.D. Suneetha et al., 2017 [104] |
Nonamethyl-phenyl-cyclopentasiloxane (19) |
Amaranthus viridis Linn. |
Green amaranth (Amaranthaceae) |
leaf |
GC/MS |
Hyderabad, Telangana, India |
D.D. Suneetha et al., 2017 [104] |
3,3-Diisopropoxy-1,1,1,5,5,5- hexamethyltrisiloxane (Diisopropyl bis(trimethylsilyl) orthosilicate) (25) |
Andrographis echioides |
False water willow (Acanthaceae) |
Leaf |
GC/MS |
Sengippatti, Tamil Nadu, India |
K. Jeevanantham and A. Zahir Hussain, 2018 [82] |
3,3-Diisopropoxy-1,1,1,5,5,5-hexamethyltrisiloxane (Diisopropyl bis(trimethylsilyl) orthosilicate) (25) |
Pteridium aquilinum (L.) |
Eagle fern |
ethanolic extract |
GC/MS |
Kanyakumari district, Tamil Nadu, India |
R.L.R. Amster and P.P.J. John, 2019 [114] |
3,3-Diisopropoxy-1,1,1,5,5,5-hexamethyltrisiloxane (Diisopropyl bis(trimethylsilyl) orthosilicate) (25) |
Blighia unijugata Baker |
Akpi,
triangle-tops evergreen tree (Sapindaceae) |
essential oil (flower) (steam distillation) |
GC/MS |
University of Ibadan, Nigeria |
D.O. Moronkola et al., 2017 [86] |
2-Chloro-6-fluorobenzyl alcohol tert-butyl dimethyl silyl ether (38) |
Pteridium aquilinum (L.) |
Eagle fern |
ethanolic extract |
GC/MS |
Kanyakumari district, Tamil Nadu, India |
R.L.R. Amster and P.P.J. John, 2019 [114] |
2,5-Bis[(trimethylsilyloxy)
benzoic acid trimethylsilyl ester (62) |
Irpex lacteus |
white-rot fungus |
|
GC/MS |
Kasauli, Himachal Pradesh, India |
R. Chaudhary and A. Tripathy, 2015 [73] |
2,5-Bis[(trimethylsilyloxy)
benzoic acid trimethylsilyl ester (62) |
Zea mays |
Sweet corn |
Volatile compounds of the corn juice |
GC/MS |
SICAU76, Sichuan Agricultural University, China |
Feng et al., 2020 [120] |
4-Methyl-2-trimethylsilyloxybenzoic acid trimethylsilyl ester (63) |
Elaeis guineensis |
Oil palm |
Palm leaf extract |
GC/MS |
Ughelli, Delta State, Nigeria |
P. Onakurhefe et al. 2019 [93] |
Methoxymethyl trimethyl silane (64) |
Elaeis guineensis |
Oil palm |
Palm leaf extract |
GC/MS |
Ughelli, Delta State, Nigeria |
P. Onakurhefe et al. 2019 [90] |
1,2-Diphenyltetramethyldisilane (65) |
Amaranthus viridis Linn. |
Green amaranth (Amaranthaceae) |
Leaf |
GC/MS |
Hyderabad, Telangana, India |
D.D. Suneetha et al., 2017 [104] |
3,5-Bis(trimethylsilyl)cycloheptatrienone (41) |
Amomum nilgiricum |
|
|
GC/MS |
Western Ghats, India |
N. Konappa et al., 2020 [129] |
3,5-Bis(trimethylsilyl)cycloheptatrienone (41) |
Dillenia scabrella |
(deciduous tree) |
leaf (methanolic extract) |
GC/MS |
West Garo Hills, District of Meghalaya, North East India |
K. Momin and S.C. Thomas, 2020 [78] |
3,5-Bis(trimethylsilyl)cycloheptatrienone (41) |
Psidium guajava |
common guava (evergreen shrub/small tree) |
Leaf (ethyl acetate extract) |
GC/MS |
Kerala, India |
R.B. Devi et al., 2018 [131] |
3,5-Bis(trimethylsilyl)cycloheptatrienone (41) |
Cinnamomum camphora |
camphor tree (evergreen tree) |
leaf (methanolic extract) |
GC/MS |
Central South University of Forestry and Technology, P. R. China |
N.-C. Li et al., 2015 [81] |
3,5-Bis(trimethylsilyl)cycloheptatrienone (41) |
Quercus aliena |
Oriental white oak (galcham oak) |
Wood |
GC/MS |
Tongbai Mountain, Henan Province, China |
Q.A. Ma et al., 2015 [171] |
3,5-Bis(trimethylsilyl)cycloheptatrienone (41) |
Dicranopteris linearis |
Old world forked fern |
Leaf |
GC/MS |
Serdang, Selangor, Malaysia |
Z. A. Zakaria et al., 2017 [121] |
3,5-Bis(trimethylsilyl)cycloheptatrienone (41) |
Andrographis echioides |
False water willow (Acanthaceae) |
Leaf |
GC/MS |
Sengippatti, Tamil Nadu, India |
K. Jeevanantham and A. Zahir Hussain, 2018 [82] |
3,5-Bis(trimethylsilyl)cycloheptatrienone (41) |
Mangifera indica |
Mango (Anacardiaceae) |
stem bark extract |
GC/MS |
Dundaye area, Usmanu Danfodiy, Nigeria |
H. Sani et al., 2015 [172] |
3,5-Bis(trimethylsilyl)cycloheptatrienone (41) |
Smallanthus sonchifolius |
yacón |
|
GC/MS |
|
O.V. Demeshko et al., 2018 [173] |
3,5-Bis(trimethylsilyl)cycloheptatrienone (41) |
Hylocereus undulates |
dragon fruit |
Stem |
GC/MS |
|
Q. Ma et al., 2015 [171] |
3,5-Bis(trimethylsilyl)cycloheptatrienone (41) |
Punica granatum |
pomegranate |
fruit rind |
GC/MS |
Supermarket bought, Vellore Institute of Technology, Vellore campus |
A. Prakash and V. Suneetha, 2014 [77] |
3,5-Bis(trimethylsilyl)cycloheptatrienone (41) |
Microcosmus exasperatus Heller |
ascidian |
methanolic extract |
GC/MS |
Tuticorin coast, India |
Meenakshi et al., 2012 [174] |
3,5-Bis(trimethylsilyl)cycloheptatrienone (41) |
Sargassum wightii |
macroalgae |
CH2Cl2 extract |
GC/MS |
South Indian coastal area, Tamil Nadu, India |
A.N. Syad et al., 2013 [175] |
3,5-Bis(trimethylsilyl)cycloheptatrienone (41) |
Aporosa lindleyana Baill |
Flowering plant (Phyllanthaceae) |
Ethanolic extract of roots |
GC/MS |
Keeriparai, Kanyakumari District, Tamilnadu, India |
S. Ramakrishnan and R. Venkataraman, 2011 [176] |
3,5-Bis(trimethylsilyl)cycloheptatrienone (41) |
Leea asiatica |
Asiatic leea (Vitaceae) |
methanolic extract |
GC/MS |
Andaman and Nicobar Islands, India |
S. Ali et al., 2021 [122] |
3,5-Bis(trimethylsilyl)cycloheptatrienone (41) |
Fritillaria pallidiflora |
Siberian fritillary |
root exudates |
|
|
Y. Wang et al., 2009 [112] |
3,5-Bis(trimethylsilyl)cycloheptatrienone (41) |
Momordica cymbalaria Hook. F. |
Karchikai - Vine (Cucurbitaceae) |
methanolic extract of the tuber |
GC/MS |
Sattur Taluk, Virudhunager District, Tamil Nadu, India |
M. Gurusamy et al., 2019 [74] |
3,5-Bis(trimethylsilyl)cycloheptatrienone (41) |
Blighia unijugata Baker |
triangle-tops evergreen tree (Sapindaceae) |
essential oil (root) |
GC/MS |
University of Ibadan, Nigeria |
D.O. Moronkola et al., 2017 [86] |
1,2-Bis(trimethylsilyl)benzene (2) |
Zea mays |
Sweet corn |
Volatile compounds of the corn juice |
GC/MS |
SICAU76, Sichuan Agricultural University, China |
Feng et al., 2020 [120] |
1,2-Bis(trimethylsilyl)benzene (2) |
Dillenia scabrella |
(deciduous tree) |
leaf (ethanolic – ethyl acetate extract) |
GC/MS |
West Garo Hills, District of Meghalaya, North East India |
K. Momin and S.C. Thomas, 2020 [78] |
1,2-Bis(trimethylsilyl)benzene (2) |
Solanum nigrum |
black nightshade |
leaf extract |
GC/MS |
Elizade University, Ilara‐mokin, Ondo state, Nigeria |
O.S. Omojokun et al., 2019 [72] |
1,2-Bis(trimethylsilyl)benzene (2) |
Dillenia scabrella |
(deciduous tree) |
leaf (methanolic extract) |
GC/MS |
West Garo Hills, District of Meghalaya, North East India |
K. Momin and S.C. Thomas, 2020 [78] |
1,2-Bis(trimethylsilyl)benzene (2) |
Cinnamomum camphora |
camphor tree (evergreen tree) |
leaf (methanolic extract) |
GC/MS |
Central South University of Forestry and Technology, P. R. China |
N.-C. Li et al., 2015 [81] |
1,2-Bis(trimethylsilyl)benzene (2) |
Punica granatum |
pomegranate |
fruit rind |
GC/MS |
Supermarket bought, Vellore Institute of Technology, Vellore campus |
A. Prakash and V. Suneetha, 2014 [77] |
1,2-Bis(trimethylsilyl)benzene (2) |
Caesalpinia bonducella |
Knicker nut |
Seed kernels (ethyl acetate extract) |
GC/MS |
Kolli hills, Nammakkal District of Tamil Nadu, India |
A. Thenmozhi, et al. 2020 [79] |
1,2-Bis(trimethylsilyl)benzene (2) |
Caesalpinia bonducella |
Knicker nut |
ethanol extract |
GC/MS |
Kolli hills, Nammakkal District of Tamil Nadu, India |
A. Thenmozhi, et al. 2020 [79] |
1,2-Bis(trimethylsilyl)benzene (2) |
Dicranopteris linearis |
Old world forked fern |
Leaf |
GC/MS |
Serdang, Selangor, Malaysia |
Z. A. Zakaria et al., 2017 [121] |
1,2-Bis(trimethylsilyl)benzene (2) |
Andrographis echioides |
False water willow (Acanthaceae) |
Leaf |
GC/MS |
Sengippatti, Tamil Nadu, India |
K. Jeevanantham and A. Zahir Hussain, 2018 [82] |
1,2-Bis(trimethylsilyl)benzene (2) |
Elaeis guineensis |
Oil palm |
Palm leaf extract |
GC/MS |
Ughelli, Delta State, Nigeria |
P. Onakurhefe et al. 2019 [93] |
1,2-Bis(trimethylsilyl)benzene (2) |
Camellia oleifera Abel. |
Tea oil camellia |
seed (oil) |
GC/MS |
Zengcheng Teaching and Research Bases, South China Agricultural University, China |
J. He et al., 2021 [90] |
1,2-Bis(trimethylsilyl)benzene (2) |
Leea asiatica |
Asiatic leea (Vitaceae) |
methanolic extract |
GC/MS |
Andaman and Nicobar Islands, India |
S. Ali et al., 2021 [122] |
1,2-Bis(trimethylsilyl)benzene (2) |
Elatostema papillosum Wedd |
Nettle plant species (Urticaceae) |
methanol extract |
GC/MS |
Chittagong district, Bangladesh |
M.Z. Uddin et al., 2021 [123] |
1,2-Bis(trimethylsilyl)benzene (2) |
Azadirachta indica |
Neem plant |
leaf extract |
GC/MS |
Ota, Ogun State, Nigeria |
D.E. Babatunde et al., 2019 [124] |
1,2-Bis(trimethylsilyl)benzene (2) |
Pteridium aquilinum (L.) |
Eagle fern |
ethanolic extract |
GC/MS |
Kanyakumari district, Tamil Nadu, India |
R.L.R. Amster and P.P.J. John, 2019 [114] |
1,2-Bis(trimethylsilyl)benzene (2) |
Abrus precatorius |
jequirity bean/rosary pea |
methanolic extract |
GC/MS |
Tamil-nadu, India |
K. Pavithra et al., 2020 [125] |
1,2-Bis(trimethylsilyl)benzene (2) |
Momordica cymbalaria Hook. F. |
Karchikai - Vine (Cucurbitaceae) |
methanolic extract of the tuber |
GC/MS |
Sattur Taluk, Virudhunager District, Tamil Nadu, India |
M. Gurusamy et al., 2019 [74] |
1,2-Bis(trimethylsilyl)benzene (2) |
Vernonia amygdalina |
bitter leaf |
leaf extract |
GC/MS |
Elizade University, Ilara‐mokin, Ondo state, Nigeria |
O.S. Omojokun et al., 2019 [72] |
1,2-Bis(trimethylsilyl)benzene (2) |
Gymnopilus spectabilis |
mushroom |
methanolic extract |
GC/MS |
southern Western Ghats, India |
V. Ragupathi et al., 2018 [75] |
1,2-Bis(trimethylsilyl)benzene (2) |
Bidens pilosa |
black-jack (Asteraceae) |
leaf (aqueous ethanolic extract) |
GC/MS |
University of Fort Hare farm, South Africa |
A.B. Falowo et al., 2017 [80] |
1,2-Bis(trimethylsilyl)benzene (2) |
Syzygium aromaticum |
clove |
aqueous extract |
GC/MS |
commercial market, Chennai, Tamil Nadu, India |
R.E. Varghese et al., 2017 [126] |
1,2-Bis(trimethylsilyl)benzene (2) |
Sesamum indicum L |
sesame (Pedaliaceae) |
Seeds (light petroleum ether extract) |
GC/MS |
different states of India |
R. Tyagi and V. Sharma, 2014 [73] |
1,2-Bis(trimethylsilyl)benzene (2) |
Blighia unijugata Baker |
triangle-tops evergreen tree (Sapindaceae) |
essential oil (root) |
GC/MS |
University of Ibadan, Nigeria |
D.O. Moronkola et al., 2017 [86] |
1,2-Bis(trimethylsilyl)benzene (2) |
Berberis vulgaris |
Common barbary |
inner bark (methanolic extract) |
GC/MS |
Siahbishe, Chalous, Mazandaran, Iran |
S.K. Hosseinihashemi et al., 2015 [115] |
1,2-Bis(trimethylsilyl)benzene (2) |
Rumex nervosus |
Nerveleaf dock |
Methanolic leaf extract Extraction was performed at King Saud University |
GC/MS |
Bait, Al-Radmah district, Ibb governorate, Yemen |
M.M. Azzam et al., 2020 [84] |
1,2-Bis(trimethylsilyl)benzene (2) |
Sceliphron Caementarium |
Mud dauber wasp |
nest (ethanolic extract) |
GC/MS |
Coimbatore, Tamil Nadu |
P. Susheela et al., 2018 [127] |
1,2-Bis(trimethylsilyl)benzene (2) |
Gardicinia kola |
Bitter kola |
n-Hexane extracts of seeds |
GC/MS |
Southwestern Nigeria |
Penduka et al., 2014 [85] |
1,2-Bis(trimethylsilyl)benzene (2) |
Desmodium gangeticum |
Shalparni (Fabaceae) |
root extract (chloroform) |
GC/MS |
Herbal garden, Mahatma Gandhi U., Kerala, India |
Srivats et al., 2012 [128] |
1,3-Bis(trimethylsilyl)benzene (1) |
Dicranopteris linearis |
Old world forked fern |
Leaf |
GC/MS |
Serdang, Selangor, Malaysia |
Z. A. Zakaria et al., 2017 [121] |
1,3-Bis(trimethylsilyl)benzene (1) |
Blighia unijugata Baker |
triangle-tops evergreen tree (Sapindaceae) |
essential oil (root) (steam distillation) |
GC/MS |
University of Ibadan, Nigeria |
D.O. Moronkola et al., 2017 [86] |
1,3-Bis(trimethylsilyl)benzene (1) |
Abrus precatorius |
jequirity bean/
rosary pea |
fruit/seeds (steam distillation) |
GC/MS |
|
Hussain and Kumaresan, 2014 [83] |
1,4-Bis(trimethylsilyl)benzene (3) |
Aporosa lindleyana Baill |
Flowering plant (Phyllanthaceae) |
Ethanolic extract of roots |
GC/MS |
Keeriparai, Kanyakumari District, Tamilnadu, India |
S. Ramakrishnan and R. Venkataraman, 2011 [176] |
1,4-Bis(trimethylsilyl)benzene (3) |
Fritillaria pallidiflora |
Siberian fritillary |
root exudates |
GC/MS |
|
Y. Wang et al., 2009 [112] |
1,4-Bis(trimethylsilyl)benzene (3) |
Caesalpinia bonducella |
Knicker nut |
Seed kernels (ethyl acetate extract) |
GC/MS |
Kolli hills, Nammakkal District of Tamil Nadu, India |
A. Thenmozhi, et al. 2020 [79] |
1,4-Bis(trimethylsilyl)benzene (3) |
Azadirachta indica |
Neem plant |
leaf extract |
GC/MS |
Ota, Ogun State, Nigeria |
D.E. Babatunde et al., 2019 [124] |
1,4-Bis(trimethylsilyl)benzene (3) |
Momordica cymbalaria Hook. F. |
Karchikai - Vine (Cucurbitaceae) |
methanolic extract of the tuber |
GC/MS |
Sattur Taluk, Virudhunager District, Tamil Nadu, India |
M. Gurusamy et al., 2019 [74] |
1,4-Bis(trimethylsilyl)benzene (3) |
Vernonia amygdalina |
Bitter leaf |
leaf extract |
GC/MS |
Elizade University, Ilara‐mokin, Ondo state, Nigeria |
O.S. Omojokun et al., 2019 [72] |
5-Methyl-2-trimethylsilyloxy-acetophenone (43) |
Bidens pilosa |
Black-jack (Asteraceae) |
leaf (aqueous ethanolic extract) |
GC/MS |
University of Fort Hare farm, South Africa |
A.B. Falowo et al., 2017 [80] |
5-Methyl-2-trimethylsilyloxy-acetophenone (43) |
Gardicinia kola |
Bitter kola |
n-Hexane extracts of seeds |
GC/MS |
Southwestern Nigeria |
Penduka et al., 2014 [78] |
5-Methyl-2-trimethylsilyloxy-acetophenone (43) |
Dicranopteris linearis |
Old world forked fern |
Leaf |
GC/MS |
Serdang, Selangor, Malaysia |
Z. A. Zakaria et al., 2017 [114] |
4-Methyl-2-trimethylsilyloxy-acetophenone (42) |
Bidens pilosa |
Black-jack (Asteraceae) |
leaf (aqueous ethanolic extract) |
GC/MS |
University of Fort Hare farm, South Africa |
A.B. Falowo et al., 2017 [73] |
4-Methyl-2-trimethylsilyloxy-acetophenone (42) |
Gardicinia kola |
Bitter kola |
n-Hexane extracts of seeds |
GC/MS |
Southwestern Nigeria |
Penduka et al., 2014 [85] |
2'-(Trimethylsiloxy)propiophenone (44) |
Momordica cymbalaria Hook. F. |
Karchikai - Vine (Cucurbitaceae) |
methanolic extract of the tuber |
GC/MS |
Sattur Taluk, Virudhunager District, Tamil Nadu, India |
M. Gurusamy et al., 2019 [74] |
2'-(Trimethylsiloxy)propiophenone (44) |
Blighia unijugata Baker |
triangle-tops evergreen tree (Sapindaceae) |
essential oil (stem) (steam distillation) |
GC/MS |
University of Ibadan, Nigeria |
D.O. Moronkola et al., 2017 [86] |
2'-(Trimethylsiloxy)propiophenone (44) |
Caesalpinia bonducella |
Knicker nut |
Seed kernels (ethyl acetate extract) |
GC/MS |
Kolli hills, Nammakkal District of Tamil Nadu, India |
A. Thenmozhi, et al. 2020 [79] |
Benzenepropanoic acid
tert-butyldimethylsilyl ester (37) |
Momordica cymbalaria Hook. F. |
Karchikai - Vine (Cucurbitaceae) |
methanolic extract of the tuber |
GC/MS |
Sattur Taluk, Virudhunager District, Tamil Nadu, India |
M. Gurusamy et al., 2019 [74] |
1,4-Phenylenebis[trimethysilane] 1,4-Bis(trimethylsilyl)benzene (3) |
Gardicinia kola |
Bitter kola |
n-Hexane extracts of seeds |
GC/MS |
Southwestern Nigeria |
Penduka et al., 2014 [85] |
Diethyl silicic acid bis (trimethylsilyl) ester (49) |
Momordica cymbalaria Hook. F. |
Karchikai - Vine (Cucurbitaceae) |
methanolic extract of the tuber |
GC/MS |
Sattur Taluk, Virudhunager District, Tamil Nadu, India |
M. Gurusamy et al., 2019 [74] |
Diethyl silicic acid bis (trimethylsilyl) ester (49) |
Caesalpinia bonducella |
Knicker nut |
Seed kernels (ethyl acetate extract) |
GC/MS |
Kolli hills, Nammakkal District of Tamil Nadu, India |
A. Thenmozhi, et al. 2020 [79] |
Diethyl silicic acid bis (trimethylsilyl) ester (49) |
Gardicinia kola |
Bitter kola |
n-Hexane extracts of seeds |
GC/MS |
Southwestern Nigeria |
Penduka et al., 2014 [85] |
Trimethyl-(4-tert-butylphenoxy)silane (35) |
Momordica cymbalaria Hook. F. |
Karchikai - Vine (Cucurbitaceae) |
methanolic extract of the tuber |
GC/MS |
Sattur Taluk, Virudhunager District, Tamil Nadu, India |
M. Gurusamy et al., 2019 [74] |
Trimethyl-(4-tert-butylphenoxy)silane (35) |
Gardicinia kola |
Bitter kola |
n-Hexane extracts of seeds |
GC/MS |
Southwestern Nigeria |
Penduka et al., 2014 [85] |
Trimethyl[5-methyl-2-(1-methylethyl) phenoxy]silane (34) (Thymol-TMS) |
Caesalpinia bonducella |
Knicker nut |
Seed kernels (ethyl acetate extract) |
GC/MS |
Kolli hills, Nammakkal District of Tamil Nadu, India |
A. Thenmozhi, et al. 2020 [79] |
Trimethyl[5-methyl-2-(1-methyl ethyl)phenoxy]-silane Thymol-TMS (34) |
Caesalpinia bonducella |
Knicker nut |
Seed kernels (ethanol extract) |
GC/MS |
Kolli hills, Nammakkal District of Tamil Nadu, India |
A. Thenmozhi, et al. 2020 [79] |
Trimethyl[4-(1-methyl-1-methoxyethyl)phenoxy]silane (33) |
Caesalpinia bonducella |
Knicker nut |
Seed kernels (ethyl acetate extract) |
GC/MS |
Kolli hills, Nammakkal District of Tamil Nadu, India |
A. Thenmozhi, et al. 2020 [79] |
Trimethyl[4-(1-methyl-1-methoxyethyl)phenoxy]silane (33) |
Gardicinia kola |
Bitter kola |
n-Hexane extracts of seeds |
GC/MS |
Southwestern Nigeria |
Penduka et al., 2014 [85] |
2-[(tert-Butyldimethylsily)oxy]-1-isopropyl dimethyl-benzene (66) |
Blighia unijugata Baker |
triangle-tops evergreen tree (Sapindaceae) |
essential oil (stem bark) (steam distillation) |
GC/MS |
University of Ibadan, Nigeria |
D.O. Moronkola et al., 2017 [86] |
2-[(tert-Butyldimethylsilyl)oxy]-1-isopropyl-4-methyl-benzene (39) |
Blighia unijugata Baker |
triangle-tops evergreen tree (Sapindaceae) |
essential oil (stem bark, stem and root) (steam distillation) |
GC/MS |
University of Ibadan, Nigeria |
D.O. Moronkola et al., 2017 [86] |
1,2-Bis(trimethylsiloxy)ethane (29) |
Berberis vulgaris |
Common barbary |
inner bark (methanolic extract) |
GC/MS |
Siahbishe, Chalous, Mazandaran, Iran |
S.K. Hosseinihashemi et al., 2015 [115] |
Trimethyl[5-methyl-2-(1-methylethyl)phenoxy]silane Thymol-TMS (34) |
Blighia unijugata Baker |
triangle-tops evergreen tree (Sapindaceae) |
essential oil (flower) (steam distillation) |
GC/MS |
University of Ibadan, Nigeria |
D.O. Moronkola et al., 2017 [86] |
Trimethyl[4-(2-methyl-4-oxo-2-pentyl)phenoxy]silane (45) 4-(4-Hydroxyphenyl)-4-methyl-2-pentanone, TMS derivative |
Blighia unijugata Baker |
triangle-tops evergreen tree (Sapindaceae) |
essential oil (stem bark, stem and root) (steam distillation) |
GC/MS |
University of Ibadan, Nigeria |
D.O. Moronkola et al., 2017 [86] |
Trimethyl[4-(2-methyl-4-oxo-2-pentyl)phenoxy] silane (45) 4-(4-Hydroxyphenyl)-4-methyl-2-pentanone, TMS derivative |
Caesalpinia bonducella |
Knicker nut |
Seed kernels (ethyl acetate extract) |
GC/MS |
Kolli hills, Nammakkal District of Tamil Nadu, India |
A. Thenmozhi, et al. 2020 [79] |
tert-Butyl-(5-isopropyl-2-methylphenoxy)dimethylsilane (39) |
Caesalpinia bonducella |
Knicker nut |
Seed kernels (ethyl acetate extract) |
GC/MS |
Kolli hills, Nammakkal District of Tamil Nadu, India |
A. Thenmozhi, et al. 2020 [79] |
Diethyl bis(trimethylsilyl) silicate (30) |
Blighia unijugata Baker |
triangle-tops evergreen tree (Sapindaceae) |
essential oil (flower) (steam distillation) |
GC/MS |
University of Ibadan, Nigeria |
D.O. Moronkola et al., 2017 [86] |
Methyltris(trimethylsiloxy)silane (31) |
Blighia unijugata Baker |
triangle-tops evergreen tree (Sapindaceae) |
essential oil (stem bark) (steam distillation) |
GC/MS |
University of Ibadan, Nigeria |
D.O. Moronkola et al., 2017 [86] |
Methyltris(trimethylsiloxy)silane (31) |
Gardicinia kola |
Bitter kola |
n-Hexane extracts of seeds |
GC/MS |
Southwestern Nigeria |
Penduka et al., 2014 [85] |
[(4-Hexylbenzene-1,3-diyl)bis(oxy)]bis (trimethylsilane) (32) |
Camellia oleifera Abel. |
Tea oil camellia |
seed (oil) |
GC/MS |
Zengcheng Teaching and Research Bases, South China Agricultural University, China |
J. He et al., 2021 [90] |
1-[Dimethyl(phenyl)silyloxy]pentane (56) |
Gardicinia kola |
Bitter kola |
n-Hexane extracts of seeds |
GC/MS |
Southwestern Nigeria |
Penduka et al., 2014 [85] |
1,2-Bis(trimethylsilyl)glyceryl linoleate (67) |
Microcosmus exasperatus Heller |
ascidian |
methanolic extract |
GC/MS |
Tuticorin coast, India |
Meenakshi et al., 2012 [174] |
1-Trimethylsilyl-2-piperidinecarboxylic acid trimethylsilyl ester (55) |
Gardicinia kola |
Bitter kola |
n-Hexane extracts of seeds |
GC/MS |
Southwestern Nigeria |
Penduka et al., 2014 [85] |
9α-Hydroxy-17β—(trimethylsiloxy)-4-androsten-3-methyloxime (69) |
Berberis vulgaris |
Common barbary |
inner bark (methanolic extract) |
GC/MS |
Siahbishe, Chalous, Mazandaran, Iran |
S.K. Hosseinihashemi et al., 2015 [115] |
3-Trimethylsiloxy-androstane-11,17-dione derivative (70) |
Sceliphron Caementarium |
Mud dauber wasp |
nest (ethanolic extract) |
GC/MS |
Coimbatore, Tamil Nadu |
P. Susheela et al., 2018 [127] |
N-(tert-Butyldimethylsilyl)-1,2-benzisothiazol-3-amine (36) |
Caesalpinia bonducella |
Knicker nut |
Seed kernels (ethyl acetate extract) |
GC/MS |
Kolli hills, Nammakkal District of Tamil Nadu, India |
A. Thenmozhi, et al. 2020 [79] |
N,N-Dimethyl-4-nitroso-3-(trimethylsilyl)aniline (57) |
Gardicinia kola |
Bitter kola |
n-Hexane extracts of seeds |
GC/MS |
Southwestern Nigeria |
Penduka et al., 2014 [85] |
N-[4-(Trimethylsilyl)phenyl]acetamide 4-(Trimethylsilyl)acetanilide (58) |
Gardicinia kola |
Bitter kola |
n-Hexane extracts of seeds |
GC/MS |
Southwestern Nigeria |
Penduka et al., 2014 [85] |
4. Conclusions
Both siloxanes and alkyl-/arylsilanes have been isolated from plant extracts as well as from other organisms such as fungi and bacteria. The relative frequency with which the different compounds are reported reflects their usage volume and anthropogenic emissions, with medium ring sized permethylated cyclosiloxanes being the most often noted compounds. This makes it highly likely that most if not all of the compounds that have been reported are of anthropogenic origin rather than natural metabolites. Under certain conditions, it is known that both septa bleed and column bleed fragments appear as ghost peaks in gas chromatography, where again medium ring sized permethylated cyclosiloxanes are typical compounds that are obtained.
Sometimes, extracts are silylated before injection into the gas chromatograph, in order to make the components more volatile. Clearly, this leads to a plethora of silylated compounds, including silylated by-products. If used, this derivatization should always be mentioned in the experimental part of a paper.