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1.
Paul W. C. Green 《Journal of chemical ecology》2009,35(9):1096-1107
Extracts of whole booklice (Liposcelis bostrychophila)—sequentially extracted in hexane and aqueous 80% methanol (80%MeOH)—repel conspecifics. A methanol-soluble fraction (MFr) of the 80% methanol extract was more repellent than either its corresponding water fraction (WFr) or the hexane extract. The repellent effect of the MFr was repeatable across extracts prepared on different occasions over a 1 month period. Gas chromatography, mass-spectrometry (GC-MS) analyses showed that saturated (C16; C18) monoenoic (C16:1; C18:1) and a dienoic fatty acid (C18:2) and the corresponding methyl esters of all but C16:1 and C18 constituted approximately 95% and 30%, of the detected compounds in the methanol fractions and the hexane extract, respectively. Qualitative thin layer chromatography showed that cholesterol was present in methanol fractions and the hexane extract, and also enabled tentative identification of triacylglycerols and phospholipids in the methanol fractions. Extracts of wheatgerm, dried skimmed milk powder, active yeast, and wholemeal flour—L. bostrychophila dietary components—were analyzed by GC-MS, and C16, C18:1 and C18:2 were detected, indicating that C18 and the methyl esters were not directly extractable and/or that they were products of booklice metabolism. A fatty acid amide (stearamide) previously identified in cuticular extracts of L. bostrychophila was not detected, and therefore was not responsible for the observed biological activity. Pure fatty acids and fatty acid methyl esters repelled settling of L. bostrychophila at 10 mM, with the exception of palmitic and stearic acids, indicating, among other things, a difference between the efficacy of saturated and unsaturated fatty acids. The effect of concentrations <10 mM was less significant, although palmiteoleic acid appeared to be attractive to L. bostrychophila at 0.1 mM. Fatty acids and fatty acid methyl esters were at a much lower concentration than 10 mM in the repellent methanol fractions, indicating that an interaction between known and as yet unidentified compounds is likely. The significance of fatty acids in relation to the biology and behavior of L. bostrychophila and their potential for use in traps and monitoring are discussed. 相似文献
2.
Tomoko Nishimaki-Mogami Ken-ichiro Minegishi Atushi Takahashi Yasushi Kawasaki Yuji Kurokawa Mitsuru Uchiyama 《Lipids》1988,23(9):869-877
Skin-surface lipids from the monkeyMacaca fascicularis are composed of sterol esters (38%), cholesterol (4%) and two types of wax diesters, identified as Type II (IIa and IIb,
17% and 40%, respectively). Type IIa contained diesters of 1,2-alkanediols esterified with two molecules of long-chain (C14−C34) fatty acids having straight and branched chains. In the diesters IIa, fatty acids shorter than C19 predominated in position 1, and fatty acids longer than C20 predominated in position 2. Type IIb contained diesters of 1,2-alkanediols esterified with C4 and C5 branched-chain fatty acids (predominantly isovaleric acid) at position 1 and long-chain (C14−C27) acids, having straight and branched chains, at position 2. The shortchain acids were converted to 2-nitrophenylhydrazides
and analyzed by high-performance liquid chromatography (HPLC). Ammonia chemical ionization (CI)-gas chromatography (GC)-mass
spectrometry (MS) resolved the intact diesters IIb into 12 peaks corresponding to molecular weights ranging from 597 to 748,
and showed that the molecular species, such as C21−C16−C5 (diol, fatty acid in position 2, fatty acid in position 1), C22−C16−C5 and C23−C16−C5, were prevalent. The fatty acids from both diesters were mostly (>98%) saturated. The 1,2-alkanediols from both diesters
consisted of C16−C26 saturated straight- and branched-chain components. The acyl groups of sterol esters contained 86% C14−C34 branched-chain acids. The unsaturated fatty acids (5.4%) belonged to a straight-chain monoenoic series having extremely long
chains (C18−C34). The branched-chain structures in the fatty acids and diols were iso and anteiso. These results show the species-specific
profile for the skin-surface lipid synthesis. 相似文献
3.
Isomeric methyl esters of fatty acids in three groups (C15, C17, C19) have been isolated from ruminant fats. Basic structural analysis by physiochemical techniques indicated that these odd-numbered
fatty acids were even chain with a single methyl branch on the chain. High resolution open-tubular gas liquid chromatographic
studies indicate that, with the exception of iso acid impurities in these fractions, only even-numbered carbons of the fatty
acid chains bear the methyl branch. 相似文献
4.
Robert R. Klein Gregory King Robert A. Moreau Gerald P. McNeill Pierre Villeneuve Michael J. Haas 《Journal of the American Oil Chemists' Society》1997,74(11):1401-1407
The fatty acid specificity and pH dependence of triacylglycerol hydrolysis by the Rhizopus delemar lipase acylbinding site mutant Val206Thr+Phe95Asp (Val, valine; Thr, threonine; Phe, phenylalanine; Asp, aspartic acid) were
characterized. The activity of the double mutant prolipase was reduced by as much as 10-fold, compared to the wild-type prolipase.
However, the fatty acid specificity profile of the enzyme was markedly sharpened and was dependent on the pH of the substrate
emulsion. At neutral pH, strong preference (10-fold or greater) for hydrolysis of triacylglycerols of medium-chainlength fatty
acids (C8:0 to C14:0) was displayed by the variant prolipase, with no hydrolysis of triacylglycerols of short-chain fatty acids (C4:0 to C6:0) and little activity manifested toward fatty acids with 16 or more carbons. At acidic pH values, the fatty acid selectivity
profile of the double mutant prolipase expanded to include short-chain triacylglycerols (C4:0, C6:0). When assayed against a triacylglycerol mixture of tributyrin, tricaprylin and triolein, the Val206Thr+Phe95Asp prolipase
displayed a high selectivity for caprylic acid and released this fatty acid at least 25-fold more efficiently than the others
present in the substrate mixture. When presented a mixture of nine fatty acid methyl esters, the wild-type prolipase showed
a broad substrate specificity profile, hydrolyzing the various methyl esters to a similar extent. Contrastingly, the double
mutant prolipase displayed a narrowed substrate specificity profile, hydrolyzing caprylic methyl ester at nearly wild-type
levels, while its activity against the other methyl esters examined was 2.5- to 5-fold lower then that observed for the wild-type
enzyme. 相似文献
5.
W. R. Morrison E. L. Jack L. M. Smith 《Journal of the American Oil Chemists' Society》1965,42(12):1142-1147
Milk lipids were fractionated by silicic acid column chromatography and preparative thinlayer chromatography (TLC). Ceramide
monohexoside (CMH), ceramide dihexoside (CDH), phosphatidyl ethanolamine (PE), phosphatidyl choline (PC), phosphatidyl serine
(PS), and sphingomyelin (Sph) were isolated, and the purity of each was checked by infrared spectroscopy and TLC. The diacylphospholipids
were hydrolyzed with phospholipase A and the products separated by TLC. Fatty acid methyl esters were prepared from the various
fractions and analyzed by gas chromatography.
The glycolipids, CMH and CDH, and Sph contained large amounts of long-chain saturated fatty acids, especially C22:0, C23:0, and C24:0, PE, PS, and PC contained C10-C22 normal and branched-chain saturated fatty acids, and C15-C20 unsaturated fatty acids (mainly monoenes). The distributions of saturated acids between the α′- and β-positions were respectively:
PE, 46 and 11%; PS, 65 and 19%; and PC, 72 and 53%. PC was exceptional in that there was 10.8% myristic acid in the β-position
and only 5.6% in the α′-position. PE and PS were similar in composition except that in PE oleic acid was evenly distributed,
and in PS was largely in the β-position. In general, PC was much more saturated than PE or PS, and there was no overall pattern
governing the specific distribution of the fatty acids in the three diacylphospholipids. Comparison with PC from other bovine
tissues and from egg lecithin showed that fatty acids are located much less specifically in milk phospholipids than in PC
from other sources.
Presented at the AOCS Meeting, Houston, Texas, April, 1965. 相似文献
6.
N. Nicolaides 《Lipids》1971,6(12):901-905
By combined gas liquid chromatography-mass spectrometry a series of monomethyl branched fatty acids was found in the fatty
acid moiety of the wax esters of vernix caseosa. The methyl branch occurred on the even C-atoms of chains ranging from C11 to C17 (some 43 compounds in all). Except for the iso acids and possibly some of the anteiso acids, these could be formed by replacement
of malonyl CoA with a molecule of methyl malonyl CoA at the point of the branch. Smaller amounts of fatty acids also were
found with two methyl branches occurring on the even C-atoms of chains ranging from C9 to C15. 相似文献
7.
Methyl esters of a Canadian Atlantic herring oil containing 62% monoethylenic fatty acids were subjected to batch fractional
distillation under vacuum on a pilot plant scale, to study the feasibility of fractionating fatty acid esters of marine oils
of low iodine value into monounsaturated fractions with increased commercial value for industrial chemical uses. A total of
64 methyl ester fractions were collected and analyzed by gas liquid chromatography. Recoveries of the major saturated and
monounsaturated acids were close to 100%, and some fractions contained over 90% of the desired 22:1 long chain monounsaturated
acids. The short chain polyunsaturated acids were recovered in good yields, but the long chain highly unsaturated acids were
recovered in yields of 60% or less due to oxidative and thermal decomposition in the particular apparatus employed. If small
amounts of unsaturated acids are acceptable, fractional distillation of low iodine value marine oils could inexpensively supply
fractions with high concentrations of methyl esters of longer chain (C20 and C22) monounsaturated and shorter chain (C14) saturated acid or (C16) saturated-monounsaturated acid mixture. 相似文献
8.
Synthesis and Surface Active Properties of Sulfonated Acrylate Esters Based on Al‐Cedre Oil
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Wagdy Ibrahim A. El-Dougdoug Mohamed Abo Riya Basma A. Mahy 《Journal of surfactants and detergents》2015,18(4):681-688
Sulfonated acrylate esters have been synthesized by using renewable raw materials such as fatty alcohols of Al‐Ceder oil. Mixed fatty acids were isolated from Al‐Ceder oil by hydrolysis; both saturated and unsaturated fatty acids were isolated from the mixed fatty acids. The methyl esters of mixed fatty acid, saturated and unsaturated acids of Al‐Cedre oil were subjected to reduction with (LiAlH4) to give the corresponding fatty alcohols. The products of the reduction process were saponified and the hydroxyl values were estimated to further confirm the reduction occurrence. The acrylate esters were synthesized by esterification of acrylic acid with fatty alcohols of C16:0, C18:0, C18:1, and C18:2 mixed saturated, mixed unsaturated and mixed fatty acids of Al‐Cedre oil, respectively. This esterification was followed by addition of NaHSO3 to form bisulfite adducts. The structures of the prepared surfactants were characterized by IR and 1HNMR spectroscopy. A series of useful surface parameters, stability towards acids and base hydrolysis and calcium stability have been determined. 相似文献
9.
Ibrahim R. Shimi Nabila A. Maroun Mamdouh Y. Kamel Hemmat H. Ragheb Mohga M. Badran 《Lipids》1974,9(6):368-373
Gas liquid chromatographic analysis of the fatty acid methyl esters from eggs ofDermacentor andersoni Stiles (Ixodidae) revealed the presence of significant quantities (15% total fatty acids) of an unidentified component with a retention time between C18∶3−C22∶0 fatty acids. Smaller amounts of the unidentified component (ca. 5% total fatty acid) also were detected in host rabbit serum. Purified, the unidentified component's methyl ester collected from the tick eggs by preparative gas liquid chromatography was partially identified and characterized by chemical and spectroscopic analyses. The evidence suggests that the unidentified component is a methyl branched C15 tricarboxylic acid containing two vicinal carboxylic acid groups. Biosynthesis of the unidentified component by the tick is under investigation. 相似文献
10.
The formation of monomeric cyclic fatty acids was studied in a model system in which partially hydrogenated soybean oil (PHSO)
was heated intermittently for 80 hr of simulated deep fat frying. Oil samples (fresh and heated) and their methyl esters were
fractionated according to their molecular size using gel permeation chromatography (GPC). Oils and GPC fractions were analyzed
for cyclic monomers by the following steps: (i) preparation of fatty acid methyl esters (FAME); (ii) microhydrogenation of
FAME; (iii) urea fractionation of hydrogenated FAME; (iv) analysis by capillary gas liquid chromatography (GLC), and (v) structural
characterization of cyclic monomer peaks by mass spectrometry (GC-MS). Under simulated frying conditions the concentration
of cyclic monomers increased from 736 ppm (0.07%) in fresh oil to 1803 ppm (0.18%) in heated oil. GC-MS with capillary columns
allowed the identification of several C18
α-disubstituted cyclohexane and cyclopentane isomers as hydrogenated methyl esters. Other noncyclic and contaminant compounds
eluting within the expected GLC retention range of cyclic monomers also were identified in all the samples and GPC fractions. 相似文献
11.
Crambe abyssinica andLunaria annua, members of the Cruciferae family, have seed oil glycerides containing ca. 55–65% of C22 and C24 unsaturated fatty acids. Fatty acids were prepared by saponification; fatty alcohols, by sodium reduction of glycerides;
liquid wax esters, byp-toluenesulfonic acid-catalyzed reaction of fatty acids with fatty alcohols; and methyl esters, by reaction of fatty acids
with diazomethane. Solid hydrogenated glyceride oils and wax esters were compared with several commercial waxes. Chemical
and physical constants were determined for the seed oils and their derivatives. Position of unsaturation in theCrambe fatty acids was determined by gas chromatographic analysis of the permanganate-periodate degradation products. The major
dicarboxylic acid was brassylic (C13), proving the docosenoic acid to be erucic.
Presented in part at the AOCS meeting in New Orleans, La., 1962.
A laboratory of the No. Utiliz. Res. & Dev. Div., ARS, U.S.D.A. 相似文献
12.
S. Warwel W. Pompetzki E. A. Deckwirth 《European Journal of Lipid Science and Technology》1991,93(6):210-215
Transition-metal Catalyzed Oxidation of Unsaturated Fatty Acids — Synthesis of Ketocarboxylic Acids and Dicarboxylic Acids Terminal unsaturated C10–C14-fatty acid methylesters (9-decenoic-, 10-un-decenoic-, 13-tetradecenoic methylesters) were converted to methylketocarboxylic methylesters (yields: 60–75%, isolated) by oxidation with O2/H2O at roomtemperature under catalysis of PdCl2/CuCl2. Using RhCl3/FeCl3 at 80°C yields of 40–60% were obtained. For the first time methyl oleate was converted directly to a mixture of 9-oxo- and 10-oxo-stearic acid methylester by palladium catalyzed oxidation. In DMF/H2O the selectivity to these two ketoesters was 85% (15% isomers), in dioxane/H2O the selectivity droped to 55% while the yield of the oxostearic acid esters climbed to 70%. The Mn-catalyzed oxidative cleavage of methylketocarboxylic acid esters with O2 at 115°C led in each case to a mixture of two dicarboxylic acid esters in a molar ratio of 2 : 1. Starting with 9-oxodecanoic acid azelaic and suberic acid were obtained at a conversion rate of 90%. Analogous 10-oxoundecanoic acid led to C10/C9- and 13-oxotetradecanoic acid led to C13/C12-dicarboxylic acids. The oxidative cleavage of 9-/10-oxostearic acid methylester yielded mixtures of C8–C10-monocarboxylic acids and methylesters of C8–C10-dicarboxylic acids. 相似文献
13.
J. J. Ellington P. F. Schlotzhauer A. I. Schepartz 《Journal of the American Oil Chemists' Society》1978,55(7):572-573
Flue-cured tobacco was subjected to alkaline hydrolysis, and, after acidification, the fatty acids and nonsaponifiables were
extracted into hexane. Treatment of the hexane extract with diazomethane yielded fatty acid methyl esters. The methyl esters
were separated from interfering hydrocarbons and sterols by preparative thin layer chromatography (PTLC). After addition of
an internal standard, the esters were quantitated by gas chromatography on the column packing, Silar 10C. Quantitation of
the C14-C32 fatty acid esters was possible by means of temperature programming. 相似文献
14.
A. D. Andrade A. F. Rubira M. Matsushita N. E. Souza 《Journal of the American Oil Chemists' Society》1995,72(10):1207-1210
Lipid and fatty acid levels in the edible flesh of 17 freshwater fish from Brazil’s southern region were determined. Analyses
of fatty acid methyl esters were performed by gas chromatography. Palmitic acid (C16:0) was the predominant saturated fatty acid, accounting for 50–70% of total saturated acids. Oleic acid (C18:1θ9) was the most abundant monounsaturated fatty acid. Linoleic acid (C18:2θ6), linolenic acid (C18:3θ3), and docosahexaenoic acid (C22:6θ3) were the predominant polyunsaturated fatty acids (PUFA). The data revealed that species such as truta, barbado, and corvina
were good sources of eicosapentaenoic acid (C20:5θ3) and docosahexaenoic acid (C22:6θ3), and that most freshwater fish examined were good sources of PUFA θ3. 相似文献
15.
Summary The methyl esters of a specimen of menhaden oil have been fractionated in an efficient still. The C12, C14, C16, and C18 main fractions have been studied, mainly by low temperature crystallization procedures. The oil has been shown to contain
traces of lauric and dodecenoic acids. The C14 acids are made up of 2.2% tetradecenoic acid and 97.8% of myristic; based on the whole ester composition of Table I, these
values amount to 0.1 and 6.8%, respectively. The C16 acids are palmitic, 50.9%; hexadecenoic, 46.6%; and hexadecatrienoic (including a small amount of tetrenoic acid) 2.5%, or
based on the whole esters, 15.5, 14.1 and 0.8%, respectively. A very rough calculation of the composition of the C18 fraction gives the following reults, values based on the whole esters being included in parenthesis: stearic, 11.5 (3.1);
octadecenoic, 58.6 (15.7); octadecadienoic, 13.4 (3.6); octadecatrienoic, 7.2 (1.9); and octadecatetrenoic, 9.3% (2.5%). In
the course of this investigation the following acids and their methyl esters were isolated from the oil by crystallization
procedures; myristic, tetradecenoic (80%), palmitic, hexadecenoic, stearic, and oleic. Evidence was presented that the octadecenoic
acids of this oil were a mixture of oleic acid with isomeric acids of this series, a finding which is in agreement with a
recent report from this laboratory (11), describing the multiple nature of the octadecenoic acids of a number of animal fats.
Presented in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Graduate School. 相似文献
16.
Kazuo Ishii Haruo Okajima Tsuyoshi Koyamatsu Youji Okada Hiroshi Watanabe 《Lipids》1988,23(7):694-700
Capillary gas chromatography-mass spectrometry (GC-MS) analysis of the sterol ester fatty acid methyl esters of the crayfish
hepatopancreas revealed the presence of at least 30 kinds of unusual furan fatty acids (F acids), which accounted for 28.49%
of the total sterol ester fatty acids. On the other hand, only small amounts were found in triacylglycerols (0.5%) and phospholipids
(0.7%). Among the F acids, 17 acids were the hitherto unknown ones, the major component being 12,15-epoxy-13,14-dimethyleicosa-12,14-dienoic
acid (F6) (41.83% of the total F acids). These novel acids possessed chain lengths of C12 to C22, with the largest concentration at C20 (45.38%), C18 (41.97%) and C16 (10.35%). Odd-numbered F acids also were found, though in a very small amount (0.4%). In the living things other than the
crayfish, the longest chain F acid (C24) was detected in the sterol ester of the carp hepatopancreas. The bullfrog, an amphibian, and the turtle, a reptilian, were
found to have F acids as well in their livers.
Olefinic furan fatty acids, which were detected by GC-MS, were found to have resulted during the analytical process from cyclodehydration
of the diketo-ene formed by autoxidation of the F acids. 相似文献
17.
D. F. Kuemmel 《Journal of the American Oil Chemists' Society》1958,35(1):41-45
Summary A direct gravimetric method has been developed for the determination of saturated fatty acids in fats, oils, and methyl esters.
The procedure involves methanolysis of the triglycerides to produce methyl esters, followed by oxidation of the unsaturated
methyl esters by potassium permanganate. The undesired, acidic oxidation products are removed by alkaline washing and the
saturated methyl esters thus isolated are weighed directly.
The method is intended for the determination of saturated fatty acids having C16 or longer carbon chains. Small quantities of C14 saturated acids will be included in the determination if present with other higher saturated acids. The method is applicable
to both natural and hydrogenated vegetable oils. It is not applicable to oils containing large amounts of C14 and lower saturated acids.
Concentrations of saturated acids ranging from 3 to 90% in known glyceride mixtures and from 0.3 to 95% in mixtures of methyl
esters were determined with an average difference from the calculated value of 0.8%. Replicate determinations on samples in
the 10 to 30% saturates range gave a standard deviation of 0.3 to 0.4%.
Presented at the spring meeting, American Oil Chemists’ Society, New Orleans, La., April 28 to May 1, 1957 相似文献
18.
Three new 10-hydroxy fatty acids, all optically active, have been prepared by the anaerobic microbiological hydration of acis-9 double bond. Substrates that formed these new hydroxy fatty acids are linoleic, linolenic, and ricinoleic acids. The hydroxyl
group has the D configuration and the methyl esters are levorotatory. Infrared, mass spectral, specific rotation and ultraviolet
data on these compounds were determined. There was no migration of the unreated double bonds at C12 and C15 in linoleic or linolenic acids. The presence of a double bond in the 10-hydroxy fatty acids significantly increased the optical
rotation of the methyl esters. The hydratase enzyme showed unusual specificity among Δ9 unsaturated acids. While it hydrates methylene interrupted and hydroxy unsaturated acids, it failed to hydrate either 9-decenoic,
12,13-epoxy- or 12-keto-cis-9-octadecenoic acids or sterculic acid.
Presented at the AOCS Meeting, San Francisco, April 1969.
No. Marketing and Nutrition Res. Div., ARS, USDA. 相似文献
19.
Thomas K. Miwa 《Journal of the American Oil Chemists' Society》1971,48(6):259-264
HCl-catalyzed ethanolysis followed by saponification readily surmounts the resistance of long chain wax esters to direct hydrolysis
by alkali. Additionally, choosing ethyl instead of methyl esters allows baseline separations between long-chain alcohols and
corresponding esters in gas liquid chromatographic (GLC) analysis of total alcohol and acid components before saponification.
Liquid wax esters were analyzed on a temperature-programmed 3% OV-1 silicone column. Geographical and genetic effects on the
variability of jojoba oil composition were investigated with five different seed samples. Major constituents in jojoba seed
oil from shrubs in the Arizona deserts, as indicated by GLC analyses of oil, ethanolysis product, isolated fatty alcohols
and methyl esters of isolated fatty acids, were C40 wax ester 30%, C42 wax ester 50% and C44 wax ester 10%; octadecenoic acid 6%; eicosenoic acid 35%, docosenoic acid 7%, eicosenol 22%, docosenol 21% and tetracosenol
4%. Oil from smaller leaved prostrate plants growing along California’s oceanside showed a slight tendency toward higher molecular
size than oils from the California desert and Arizona specimens. The wax esters are made up of a dispro-portionately large
amount of docosenyl eicosenoate and are not a random combination of constituent acids and alcohols.Lunaria annua synthetic wax ester oil was used as a model for evaluating the analytical procedures.
Presented at the AOCS Meeting, Chicago, September 1970
No. Utiliz, Res. Dev. Div., ARS, USDA. 相似文献
20.
Zi-Long Deng Jian-Ping Yuan Yan Zhang Xiao-Ming Xu Chou-Fei Wu Juan Peng Jiang-Hai Wang 《Journal of the American Oil Chemists' Society》2013,90(10):1495-1502
Free and esterified ergosterols are detected almost solely in fungi and are often employed as a biomarker of living fungi. In this work, the fatty acid composition and δ13C values of major fatty acids in triglycerides and ergosteryl esters from the fungus Ganoderma lucidum were analyzed by gas chromatography–mass spectrometer and gas chromatography–isotopic ratio mass spectrometer, respectively. The results showed that the fatty acid profiles varied in triglycerides and ergosteryl esters. The percentage of saturated fatty acids in ergosteryl esters was remarkably higher than that in triglycerides, where C18:1Δ9c was the predominant fatty acid and constituted 61.26 % of the total fatty acids. In contrast, C16:0 was the predominant fatty acid and constituted 71.88 % of the total fatty acids in ergosteryl esters. The study suggests that, after fungal death, free ergosterols in the cell membrane of the dead fungus were esterified with preferentially saturated fatty acids, mainly C16:0, from triglycerides and then stored in lipid particles for a longer period while free ergosterol markedly decreased. The δ13C values of C16:0, C18:0, C18:1 and C18:2 in ergosteryl esters exhibit a pronounced depletion in 13C compared with that in triglycerides within the range of ?1.3 to ?0.9 ‰, supporting the above inference. It is again suggested that free ergosterol in the cell membrane should be used as an indicator of living fungi, and ergosteryl esters in the lipid particles should not be included in the measurement of living fungal biomass. 相似文献