DIFFERENTIATION OF SOME YEAST SPECIES BY CAPILLARY GAS CHROMATOGRAPHIC ANALYSIS OF CELLULAR FATTY ACIDS

The cellular fatty acids from a total of 62 strains of Torulopsis glabrata (T. glabrata), Saccharomyces cerevisiae (S. cerevisiae), Rhodotorula rubra (R. rubra), Candida krusei (C. krusei), Candida albicans (C. albicans) and Candida tropicalis (C. tropicalis) were examined by capillary gas chromatography. On the basis of fatty acid composition, all strains could be differentiated as to species. These results indicate that capillary gas chromatographic analysis of cellular fatty acids is likely to be useful for rapid identification or grouping of newer isolates of yeast species.

Nutritional evaluation,fatty acid analysis and anticancer properties investigation of seeds from kan-zaw,a potential diet oil and medicinal plant

Payenapara lleloneura Kurz.(Kan-zaw),an endemic medicinal plant only found in Tanintharyi Region of Myanmar,is widely used in the treatment of various cancer and different ailments.In the present research,the seeds were phytochemical investigated for their nutritional potential for their use as functional foods or novel diet oil resources.Nutritional evaluation showed that the seeds are rich in fats and carbohydrates(soluble sugars and starch).Fatty acid analyses showed that the seeds accumulate very richα-eleostearic acid(α-ESA,18:3^(Δ9 cis,11-trans),13 trans),an important conjugated fatty acid,up to more than 70% of total fatty acids.The seed oil derived from the Kan-zaw tree contains approximately 3.25% β-eleostearic acid(18:3^(Δ9 trans,11 trans,13 trans)),an unusual conjugated fatty acid that imparts a potent anticancer application and industrially important drying qualities to Kan-zaw oil.Physicochemical properties of the Kan-zaw seeds were examined;petroleum ether(60–90℃)extract of seed oils were also investigated for the saponification value,iodine value and estimation of acid value.Further,the present study investigated cytotoxic potential of ethanol,methanol,acetone,chloroform Kan-zaw seed extracts and commercial Kan-zaw oil against human cervical cancer cell line(HeLa).The Kan-zaw extracts and oil have shown significant anticancer activity on HeLa cells.

Fatty Acid Composition of Seed Oil from Fremontodendron californicum

The fatty acid composition of the low water-use shrub Fremontodendron californicum was examined by high temperature capillary gas chromatography. The ground seeds were extracted by supercritical fluid extraction (SFE) to obtain the oil (25.6% w/w) and for subsequent determination of the fatty acid composition. There are five fatty acids present at 1.0% or greater with linoleic 71% of the total. Oleic, palmitic, stearic, vaccenic plus traces of palmitoleic and linolenic comprise the remainder. The fatty acid methyl ester composition would make the oil suitable for biodiesel production.

Soil Microbial Community Composition During Natural Recovery in the Loess Plateau, China

This study aimed to determine the characteristics of soil microbial community composition and its relationship with soil chemical properties during natural recovery in the Loess Plateau.The soil microbial community composition was analyzed by comparing the soil microbial phospholipid fatty acids（PLFAs） of eight croplands abandoned for 1,3,5,10,13,15,20,and 30 yr in the Dunshan watershed,northern Loess Plateau,China.The results showed that soil organic carbon,total nitrogen,soil microbial biomass carbon,and soil microbial biomass nitrogen significantly increased with the abandonment duration,whereas the metabolic quotient significantly decreased.The Shannon richness and Shannon evenness of PLFAs significantly increased after 10 yr of abandonment.Gram-negative,Gram-positive,bacterial,fungal,and total PLFAs linearly increased with increased abandonment duration.Redundancy analysis showed that the abandonment duration was the most important environmental factor in determining the PLFA microbial community composition.The soil microbial PLFAs changed from anteiso-to iso-,unsaturated to saturated,and short-to long-chain during natural recovery.Therefore,in the Loess Plateau,cropland abandonment for natural recovery resulted in the increase of the soil microbial PLFA biomass and microbial PLFA species and changed the microbial from chemolithotrophic to a more heterotrophic community.

Soil microbial community structure and activity in a 100-year-old fertilization and crop rotation experiment

Aims Nitrogen(N)fertilization and lime addition may affect soil micro-bial and nematode communities and ecosystem functions through changing environmental conditions,such as soil pH and soil organic carbon.The objectives of this experiment were to examine the impact of N input and liming on soil microbial and nematode communities and to identify the key environmental determinant of community composition in a century-old fertilization and crop rota-tion experiment.Methods The field experiment consisting of a 3-year crop rotation regime was established in 1911 in southeastern USA.Four treatments,(i)no-input control,(ii)NPK with winter legume,(iii)PK with legume and lime and(iv)NPK with legume and lime,were included in this study.soil samples collected at the 0-5 cm depth were used to determine the bacterial growth rate by the 3H-thymidine incorporation technique.Incorporation of 13C into neutral lipids,glycolipids and phospholipid fatty acids(PlFas)was measured after incubation of soil with 13C-labeled acetate for 24 h.Free-living nematodes in fresh soil were extracted using a density sucrose centrifugal flotation method and identified to trophic group level.Important Findingsliming resulted in a 10-fold increase in bacterial growth rates compared with the no-input control,whereas N fertilization had no significant effect.multivariate analysis of PlFa profiles showed that soil microbial community composition was different among the four treatments;the difference was primarily driven by soil pH.PlFas indicative of gram-negative bacteria covaried with soil pH,but not those of fungi and actinobacteria.liming enhanced 13C incorpora-tion into neutral lipids,glycolipids and phospholipids by 2-15 times.In addition,13C incorporation into 16:0,16:1ω9,18:1ω9,18:1ω7 and 18:2ω6 were greater than other PlFas,suggesting that gram-negative bacteria and fungi were more active and sensitive to simple C input.bacterivorous nematodes were the dominant trophic group in the soil,but no significant differences in nematode communities were found among the treatments.our results suggest that soil pH had a greater impact than N fertilization on soil microbial community composition and activity in a crop rotation system including legumes.