Relative Content Of Fatty Acids Research Articles

Analyzing the differences and correlations between key metabolites and dominant microorganisms in different regions of Daqu based on off-target metabolomics and high-throughput sequencing

Daqu is usually produced in an open environment, which makes its quality unstable. The microbial community of Daqu largely determines its quality. Therefore, in order to improve the fermentation characteristics of Daqu, samples were collected from Jinsha County (MT1), Xishui County (MT2), and Maotai Town (MT3) in Guizhou Province to explore the microbial diversity of Daqu and its impact on Daqu's metabolites.Off-target metabolomics was used to detect metabolites, and high-throughput sequencing was used to detect microorganisms. Metabolomics results revealed that MT1 and MT2 had the highest relative fatty acid content, whereas MT3 had the highest organooxygen compound content. Principal component analysis and partial least squares discriminant analysis revealed significant differences in the metabolites among the three groups, followed by the identification of 33 differential metabolites (key metabolites) filtered using the criteria of variable importance in projection >1 and p < 0.001. According to the microbiological results, Proteobacteria was the dominant bacteria phylum in three samples. Gammaproteobacteria was the dominant class in MT1(26.84 %) and MT2(36.54 %), MT3 is Alphaproteobacteria(25.66 %). And Caulobacteraceae was the dominant family per the abundance analysis, MTI was 24.32 %, MT2 and MT3 were 33.71 % and 24.40 % respectively. Three samples dominant fungi phylum were Ascomycota, and dominant fungi family were Thermoascaceae. Pseudomonas showed a significant positive connection with various fatty acyls, according to correlation analyses between dominant microorganisms (genus level) and key metabolites. Fatty acyls and Thermomyces showed a positive correlation, but Thermoascus had the reverse relation. These findings offer a theoretical framework for future studies on the impact of metabolites on Baijiu quality during fermentation.

An in situ and real-time analytical method for detection of freeze-thew cycles in tuna via IKnife rapid evaporative ionization mass spectrometry

Freezing is one of the most commonly used preservation methods for Bluefin tuna (Thunnus orientalis). However, repeated freezing and thawing would inevitably occur due to the temperature fluctuation, leading to the microstructure damage, lipid oxidation and protein integrity decline of tuna muscle without notable visual appearance change. In this study, we used a rapid evaporative ionization mass spectrometry (REIMS) technique for the real-time determination of the extent of repeated freezing and thawing cycles in tuna fillets. We found significant variance in the relative abundance of fatty acids between bluefin tuna and its fresh counterpart following freeze-thaw cycles. Meanwhile, the difference is statistically significant (p < 0.05). The quality of tuna remains largely unaffected by a single freeze-thaw cycle but significantly deteriorates after freeze-thaw cycles (freeze-thaw count ≥2), and the relative fatty acid content of the ionized aerosol analysis in the REIMS system positively correlated with the number of freeze-thaw cycles. Notably, palmitic acid (C 16:0, m/z 255.23), oleic acid (C 18:1, m/z 281.24), and docosahexaenoic acid (C 22:6, m/z 327.23) displayed the most pronounced changes within the spectrum of fatty acid groups.

An Evaluation of the Edible Value of Salvia miltiorrhiza Seeds: Proximate Composition, Phytochemical Components and Antioxidant Activity.

Salvia miltiorrhiza seeds (SMS) are the main by-product of the production processing of Radix Salviae Miltiorrhizae. The main purposes of this work are to analyse the nutritional components in SMS, to explore the antioxidant activity of the chemical components in SMS and to evaluate the possibility of SMS as a raw material for functional foods. The contents of crude fibre, total protein, carbohydrates, total phenolics and flavonoids in SMS and the composition and relative content of fatty acids in SMS oil were determined. The results suggested that SMS has high contents of crude fibre (28.68 ± 4.66 g/100 g), total protein (26.65 ± 2.51 g/100 g), total phenolics (6.45 ± 0.55 mg of gallic acid equivalent/g) and total flavonoids (3.28 ± 0.34 mg of rutin equivalent/g), as well as a high level of α-linolenic acid (33.774 ± 4.68%) in their oil. Twenty-two secondary metabolites were identified in SMS residue, and nine compounds were isolated. The IC50 values of the total phenolic content in SMS on an ABTS radical, DPPH radical, superoxide radical and hydroxyl radical were 30.94 ± 3.68 μg/mL, 34.93 ± 4.12 μg/mL, 150.87 ± 17.64 μg/mL and 230.19 ± 24.47 μg/mL, respectively. The results indicate that SMS contain many nutrients and have high utilization value as a promising functional food.

A high-throughput platform enables in situ screening of fatty acid-producing strains using laser ablation electrospray ionization mass spectrometry and a Python package

Microbial fatty acid-producing strains are commonly engineered to improve their performance for industrial applications. However, it is challenging to efficiently and rapidly screen target strains for engineering. This study reported an in situ analytical platform using laser ablation electrospray ionization mass spectrometry (LAESI-MS) for fast profiling of triacylglycerols in cellular lipid droplets of Aurantiochytrium sp. colonies cultured on agar plates. LAESI-MS approach allowed for the direct acquisition of a colony cell's characteristic fingerprint mass spectrum and MS/MS facilitated the identification of triacylglycerol species containing three fatty acyl groups. The fatty acid contents of colony cells were calculated based on the intensities of triacylglycerols from their characteristic fingerprint mass spectrum. A Python package called TAFA-LEMS (Triacylglycerol to Fatty Acid by LAESI-MS) was also developed to process the high-throughput MS data and extract fatty acid contents in colony cells. The results demonstrated that the LAESI-MS platform is fast, stable, and reproducible, with a data acquisition rate of ≤2 s per sampling point and ≤13.69% RSDs of the relative contents of fatty acids. In addition, LAESI-MS was successfully performed on the analysis of P. tricornutum and Y lipolytica strains. This in situ MS platform has the potential to become a common biotechnology platform for microbial strain engineering.

Short-term nitrogen deposition changes chemical composition of litter and soil organic matter in a Moso bamboo forest

To investigate the effects of short-term nitrogen (N) deposition on organic matter composition of litter and soil in Moso bamboo (Phyllostachys edulis) forests, we established a N-addition treatments (50 kg N·hm-2·a-1) to simulate the ambient and N deposition in a subtropical Moso bamboo forest from July 2020 to January 2022. We analyzed the organic matter composition of Moso bamboo leaf/root litter and soil by using pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) technique. The results showed that short-term N deposition significantly increased the relative content of soil phenols by 50.9%, while significantly decreased fatty acids by 26.3%. The rela-tive content of alkanes & alkenes and lignin in leaf litter was significantly increased by 51.9% and 33.5%, respectively, while that of phenols and polysaccharides significantly decreased by 52.2% and 56.3%. In root litter, eleva-ted N significantly decreased the relative content of polycyclic aromatic hydrocarbons by 16.6%. Moreover, the relative content of fatty acids in soil organic matter was significantly positively correlated with the relative content of poly-saccharides in leaf litter. The relative content of phenols in soil organic matter was significantly positively correlated with the relative content of lignin, and negatively correlated with the relative content of polysaccharides in leaf litter. Our results demonstrated that short-term N deposition did not change the concentration of total organic carbon, total nitrogen, and C/N of the soil, leaf litter, and root litter, but significantly altered the chemical composition of organic matter. In addition, the changes in chemical composition of organic matter in soil under short-term N deposition were affected by the composition of organic matter in leaf litter.

Lavandula austroapennina: Assessment of the Antiviral Activity of Lipophilic Extracts from Its Organs.

In a framework aimed at the recovery and enhancement of medicinal plants endemic to the territory of the Cilento and Vallo di Diano National Park, Lavandula austroapennina N.G. Passal., Tundis and Upson has aroused interest. An insight into the chemical composition of the corolla, calyx, leaf, stem, and root organs was carried out following ultrasound-assisted maceration in n-hexane. The obtained lipophilic extracts were explored using ultra-high-performance chromatography coupled to high-resolution mass spectrometry (UHPLC-ESI-QqTOF-MS/MS). The extracts from the different organs varied in their relative content of fatty acids, ursanes, and oleanane-type triterpenes. In particular, the oleanolic acid content appeared to increase in the order of corolla < leaf < stem. An MTT assay was performed to verify the possible cytotoxicity of the organ extracts of L. austroapennina at a concentration ranging from 12.5 to 400 µg/mL on the Vero CCL-81 cell line. Antiviral activity against herpes simplex virus type 1 (HSV-1), alpha human coronavirus 229E (HCoV-229E), and poliovirus type 1 (PV-1) was evaluated via a plaque reduction assay in the same cellular model. All the extracts did not show cytotoxic effects after 2 and 24 h exposure times, and the antiviral efficacy was particularly important for the stem extract, capable of completely inhibiting the tested viruses at low doses. The antiviral activity in a non-enveloped virus PV-1 allowed the assertion that the extracts from the organs of L. austroapennina, and especially the stem extract, interfered directly with the viral envelope. This study underlines how much knowledge of a territory's medicinal plant heritage is a harbinger of promising discoveries in the health field.

Development of a High Oleic Cardoon Cell Culture Platform by SAD Overexpression and RNAi-Mediated FAD2.2 Silencing.

The development of effective tools for the sustainable supply of phyto-ingredients and natural substances with reduced environmental footprints can help mitigate the dramatic scenario of climate change. Plant cell cultures-based biorefineries can be a technological advancement to face this challenge and offer a potentially unlimited availability of natural substances, in a standardized composition and devoid of the seasonal variability of cultivated plants. Monounsaturated (MUFA) fatty acids are attracting considerable attention as supplements for biodegradable plastics, bio-additives for the cosmetic industry, and bio-lubricants. Cardoon (Cynara cardunculus L. var. altilis) callus cultures accumulate fatty acids and polyphenols and are therefore suitable for large-scale production of biochemicals and valuable compounds, as well as biofuel precursors. With the aim of boosting their potential uses, we designed a biotechnological approach to increase oleic acid content through Agrobacterium tumefaciens-mediated metabolic engineering. Bioinformatic data mining in the C. cardunculus transcriptome allowed the selection and molecular characterization of SAD (stearic acid desaturase) and FAD2.2 (fatty acid desaturase) genes, coding for key enzymes in oleic and linoleic acid formation, as targets for metabolic engineering. A total of 22 and 27 fast-growing independent CcSAD overexpressing (OE) and CcFAD2.2 RNAi knocked out (KO) transgenic lines were obtained. Further characterization of five independent transgenic lines for each construct demonstrated that, successfully, SAD overexpression increased linoleic acid content, e.g., to 42.5%, of the relative fatty acid content, in the CcSADOE6 line compared with 30.4% in the wild type (WT), whereas FAD2.2 silencing reduced linoleic acid in favor of the accumulation of its precursor, oleic acid, e.g., to almost 57% of the relative fatty acid content in the CcFAD2.2KO2 line with respect to 17.7% in the WT. Moreover, CcSADOE6 and CcFAD2.2KO2 were also characterized by a significant increase in total polyphenolic content up to about 4.7 and 4.1 mg/g DW as compared with 2.7 mg/g DW in the WT, mainly due to the accumulation of dicaffeoyl quinic and feruloyl quinic acids. These results pose the basis for the effective creation of an engineered cardoon cells-based biorefinery accumulating high levels of valuable compounds from primary and specialized metabolism to meet the industrial demand for renewable and sustainable sources of innovative bioproducts.

Quality characteristics of field muskmelon seed oil extracted by different processes

Field muskmelon seeds contain plenty of oil. However, its potential as vegetable food oil has not been explored comprehensively. This study used three different processes, cold extrusion (CE), coasting followed by cold extrusion (R-CE), and supercritical fluid extraction (SFE), for the extraction of field muskmelon seed oil (FMSO) and studied its quality characteristics such as color, fatty acid composition, and volatile components. The study found that FMSO is abundant in unsaturated fatty acids (UFA) and has a pleasant aroma. Gas chromatography-mass spectrometry (GC-MS) revealed that FMSO contains five main fatty acids, palmitic (11.85 ± 0.03 to12.52 ± 0.03%), linoleic (60.94 ± 1.31 to 64.78 ± 0.77%), oleic (16.64 ± 0.26 to 18.95 ± 0.47%), elaidic (0.85 ± 0.05 to 1.06 ± 0.03%), and stearic (5.67 ± 0.03 to 8.44 ± 0.06%) acids. The relative content of fatty acids showed significant variation depending on the extraction process (P < 0.05). Furthermore, volatile components were obtained by headspace solid-phase microextraction (HS-SPME) and analyzed by GC-MS. In total, 42, 53, and 91 volatile components were identified in FMSO extracted by CE, R-CE, and SFE, respectively. R-CE extraction promoted pyrazines content (51.51 ± 3.15%) and reduced esters and acids, while SFE extraction promoted the contents of hydrocarbons (26.00 ± 2.10%) and aldehydes (26.00 ± 2.78%). Meanwhile, the contents of esters (13.43±0.6%), alcohols (12.81 ± 0.16%), and acids (11.41 ± 0.23%) were higher in CE extracted FMSO than that extracted by R-CE and SFE. These results suggest that FMSO with high UFA content and pleasant aroma could be a potential source of vegetable food oil.

Metabolomic Evaluation of the Central Metabolic Pathways of Mannosylerythritol Lipid Biosynthesis in Moesziomyces antarcticus T-34.

Moesziomyces antarcticus is a basidiomycetous yeast that produces mannosylerythritol lipids (MELs), which have potential applications as bio-based functional materials in various oleochemical industries, the cosmetics, toiletry, agriculture, and pharmaceutical industries. To better understand the MEL producer, we characterized the central metabolic pathways of M. antarcticus strain T-34 grown on glucose or olive oil via metabolomics. The relative fatty acid content was higher in the cells cultured in olive oil compared to glucose, while the acetyl-CoA content was lower in cells cultured in olive oil. The levels of the tricarboxylic acid cycle metabolites citrate/isocitrate, α-ketoglutarate, and succinate were lower in olive oil compared to glucose, while fumarate and malate levels exhibited the opposite pattern. Pyruvate was not detected in olive oil compared to glucose culture. The levels of glycerol, as well as trehalose, myo-inositol, threitol/erythritol, and mannitol/sorbitol, were higher in olive oil compared to glucose cultures. The ATP level was lower in olive oil compared to glucose culture, although the assimilation of fatty acids produced by digestion of olive oil should promote large amounts of ATP production. The possibility that ATP regeneration by respiratory chain complex promote oil utilization and MEL production in M. antarcticus T-34 was found based on the results of this metabolomic analysis.

The features of the fatty acid composition of Pyrus L. total lipids are determined by mountain ecosystem conditions

The composition of fatty acids (FAs) of total lipids of pericarp, seeds, and leaves of Pyrus caucasica Fed. and Pyrus communis L. growing in mountain ecosystems at different altitudes (300, 700 and 1200 m) was studied. It was found that the greatest differences in the relative content of FAs within a species, depending on the altitudes above sea level, were characteristic of the outer tissues of the pericarp (peel) and leaves, which were in direct contact with the external environment. Pericarp parenchyma to a lesser extent, and seeds practically did not differ in FA composition at different heights. At altitudes with increased UV radiation, conjugated octadecadienoates: rumenic acid (9,11–18:2) and 10,12–18:2 were registered in the pericarp and leaf of Purys L., the functions of which in plants were practically not studied. The wild P. caucasica at all growing altitudes was characterized by more very-long-chain FAs (VLCFAs) than the P. communis cultivar. At 700 m, most likely when exposed to fungal infections, the relative number of VLCFAs increased significantly, and new species of individual odd-chaine FAs appeared in their composition in both representatives. It was especially worth noting the appearance in peel and leaf melissic acid (30:0), which was rarely recorded in the plant. A characteristic feature of only P. communis at an altitude of 700 m was the large number of unsaturated individual VLCFAs. Based on the data obtained, a scheme of possible pathways for VLCFA biosynthesis in P. communis were proposed.

Phenotypic convergence in a natural Daphnia population acclimated to low temperature.

Fluidity of a given membrane decreases at lower ambient temperatures, whereas it rises at increasing temperatures, which is achieved through changes in membrane lipid composition. In consistence with homeoviscous adaptation theory, lower temperatures result in increased tissue concentrations of polyunsaturated fatty acids (PUFAs) in Daphnia magna, suggesting a higher PUFA requirement at lower temperatures. However, so far homeoviscous adaptation has been suggested for single or geographically separated Daphnia genotypes only. Here, we investigated changes in relative fatty acid (FA) tissue concentrations in response to a lower temperature (15°C) within a D. magna population. We determined juvenile growth rates (JGR) and FA patterns of 14 genotypes that were grown on Chlamydomonas klinobasis at 15°C and 20°C. We report significant differences of JGR and the relative body content of various FAs between genotypes at either temperature and between temperatures. Based on slopes of reaction norms, we found genotype‐specific changes in FA profiles between temperatures suggesting that genotypes have different strategies to cope with changing temperatures. In a hierarchical clustering analysis, we grouped genotypes according to differences in direction and magnitude of changes in relative FA content, which resulted in three clusters of genotypes following different patterns of changes in FA composition. These patterns suggest a lower importance of the PUFA eicosapentaenoic acid (EPA, C20:5ω3) than previously assumed. We calculated an unsaturation index (UI) as a proxy for membrane fluidity at 15°C, and we neither found significant differences for this UI nor for fitness, measured as JGR, between the three genotype clusters. We conclude that these three genotype clusters represent different physiological solutions to temperature changes by altering the relative share of different FAs, but that their phenotypes converge with respect to membrane fluidity and JGR. These clusters will be subjected to different degrees of PUFA limitation when sharing the same diet.

Analysis of Derivatized N-Acyl Amino Acid Surfactants Using HPLC and HPLC/MS

A method for the analysis of weak anionic surfactants based on N-acyl amino acids was developed. The surfactants were derivatized using 2,4′-dibromoacetophenone yielding 4′-bromophenacyl esters suitable for spectrophotometric detection. Surfactants containing glycine, threonine and glutamic acid were analyzed after derivatization using reversed-phase liquid chromatography with UV/Vis and MS detection. The gradient profile was optimized using isocratic retention data of N-acyl-linked fatty acid homologues. The relative content of the homologues of N-acyl-linked fatty acids was expressed using the determined method. The intraday repeatability and stability of the prepared derivatives was tested. The relative content of fatty acids in the surfactants was correlated with the most common sources of fatty acids, showing high Pearson’s correlation coefficients with the typical fatty acids profile of a coconut oil.

Metabolite profiling of rhizosphere soil of different allelopathic potential rice accessions

BackgroundIdentification of the allelopathy-interrelated metabolites from the allelopathic rice rhizosphere is crucial to understand the allelopathic mechanism of rice, which in turn can promote its applications to farming. In this study, the metabolites from the rhizosphere soil of five different rice lines, including allelopathic rice accession PI312777 (PI) and non-allelopathic rice accession Lemont (Le) as well as their genetic derivatives (e.g., phenylalanine ammonia-lyase (PAL) gene overexpression transgenic lines of PI and Le, namely, PO and LO respectively, and PAL RNA interference line of PI, namely, PR) were identified and comparatively analyzed to explore the positive compounds that are involved in the process of rice allelopathy.ResultsThe results showed that 21 non-polar compounds and 21 polar compounds differed in content in the rhizosphere soil of PI and Le, which include several volatile fatty acids and long-chain fatty acids. The relative contents of fatty acids also differed between PAL overexpressing or RNA interference (RNAi)-silenced line and their wild-type respectively. Acetic acid content also differed among groups, i.e., it is higher in the high allelopathic potential rice. Further analysis showed that different metabolites from the ADS8 resin-extracted phase were more abundant than that those from the ADS21 resin-extracted phase, suggesting that the allelochemicals in root exudates of allelopathic rice are mainly non-polar substances. KEGG annotation of these differential metabolites revealed that these compounds were related to nutrient metabolism, secondary metabolite synthesis, signaling substance synthesis, and toxin degradation.ConclusionsRice allelochemicals deposited in the ADS8 resin-extracted phase were more abundant than those in the ADS21 resin-extracted phase. Allelochemicals in root exudates of allelopathic rice are mainly non-polar substances, and long-chain fatty acids are considered as allelopathy interrelated metabolites.

Determination of Molecular Structures of Acetone Solutes from Natural Rubber by Pyrolysis Gas Chromatography Coupled to Mass Spectrometry

As the non-isoprene components, acetone solutes (AS) from natural rubber (NR) are a crude mixture impacting the processing and mechanical properties of natural rubber significantly. Thus, illustrating the compositions and molecular structures of AS clearly is useful to grasp the inherent features of NR. Therefore, the compositions of AS from different NR (coded as WF, STR, SMR and MRSS) were investigated effectively via stepped pyrolysis gas chromatography coupled to mass spectrometry (PyGC–MS), as well as the assistance of thermogravimetric analysis (TGA). The results demonstrated that two degradation stages showed up in TGA curves for all AS samples. Principally the volatilization of higher aliphatic acids like linoleic acid and stearic acid determined by PyGC–MS induced the first degradation stage. Moreover, the decomposition of polyisoprene with low molecular weight chiefly caused the second degradation stage according to the results from PyGC–MS. Finally, the relative contents of fatty acids in AS can be arranged as AS-STR > AS-WF > AS-SMR > AS-MRSS based on the conclusions of GC–MS. The results are meaningful to the development of NR basic theory. Schematic of the preparation and analysis of AS

A new low linolenic acid allele of GmFAD3A gene in soybean PE1690

Relative fatty acid content of soybean oil is about 12 % palmitic acid, 4 % stearic acid, 23 % oleic acid, 54 % linoleic acid, and 8 % linolenic acid. To improve oxidative stability and quality of oil, breeding programs have mainly focused on reducing saturated fatty acids, increasing oleic acid, and reducing linolenic acid in soybean oil. The objective of this study was to characterize the low linolenic acid trait in seed oil of PE1690, which was derived from an ethyl methanesulfonated-mediated mutagenesis. PE1690 DNA was used to examine the genomic sequence of a candidate gene, and we found a point mutation which substituted guanine to adenine in the second intron splice site of the GmFAD3A gene. Mutation of PE1690 at the first base of the second intron caused missplicing which led to the inclusion of 334 bp of the second intron into the coding sequence. The amino acid sequence of the mutant was analyzed based on cDNA sequence of GmFAD3A in PE1690. The position 128 amino acid, which codes for tryptophan (TGG) in PE1690, was changed to a premature stop codon (TGA). Therefore, the single base mutation in the PE1690 GmFAD3A gene renders the desaturase enzyme nonfunctional. Based on a genetic marker that we developed, the association of the PE1690 derived GmFAD3A allele with linolenic acid level was tested in 89 F2 progeny of a cross between Pungsannamul (wild type) × PE1690. The results showed that the mutation of GmFAD3A in PE1690 was associated with reduced linolenic acid content in the soybean seed oil. A newly developed low linolenic acid soybean PE1690 provides a good genetic resource to improve the quality of soybean oil.

Adipose tissuetrans-fatty acids and changes in body weight and waist circumference

Previous studies have suggested that the intake of trans-fatty acids (TFA) plays a role in the development of obesity. The proportions of adipose tissue fatty acids not synthesised endogenously in humans, such as TFA, usually correlate well with the dietary intake. Hence, the use of these biomarkers may provide a more accurate measure of habitual TFA intake than that obtained with dietary questionnaires. The objective of the present study was to investigate the associations between the proportions of specific TFA in adipose tissue and subsequent changes in weight and waist circumference (WC). The relative content of fatty acids in adipose tissue biopsies from a random sample of 996 men and women aged 50-64 years drawn from a Danish cohort study was determined by GC. Baseline data on weight, WC and potential confounders were available together with information on weight and WC 5 years after enrolment. The exposure measures were total trans-octadecenoic acids (18:1t), 18:1 Δ6-10t, vaccenic acid (18:1 Δ11t) and rumenic acid (18:2 Δ9c, 11t). Data were analysed using multiple regression with cubic spline modelling. The median proportion of total adipose tissue 18:1t was 1.52% (90% central range 0.98, 2.19) in men and 1.47% (1.01, 2.19) in women. No significant associations were observed between the proportions of total 18:1t, 18:1 Δ6-10t, vaccenic acid or rumenic acid and changes in weight or WC. The present study suggests that the proportions of specific TFA in adipose tissue are not associated with subsequent changes in weight or WC within the exposure range observed in this population.

PH-upshock yields more lipids in nitrogen-starved Neochloris oleoabundans

This study explores the influence of alkaline pH and light intensity on the performance of Neochloris oleoabundans in two-stage batch cultivation: a first stage for nitrogen-sufficient growth followed by a second stage for lipid accumulation under nitrogen starvation. The highest TAG yield on absorbed light was obtained at low light conditions when pre-cultivation occurred at pH 8 and lipid accumulation was induced at pH 10. However, a higher alkaline pH by itself appears not to enhance the starvation-induced increase in lipid contents, except when combined with high light and pre-cultivation occurs at those same conditions. Such strategy however also results in low biomass and TAG yields on absorbed light. Fatty acid composition analysis revealed that the relative fatty acid contents of the TAG pool are nevertheless independent from the light intensity and pH applied at either cultivation stage, suggesting a high specificity of N. oleoabundans cell machinery towards TAG production.

Synthesis of biodiesel from Nigella sativa seed oil using surfactant-Brønsted acidic-combined ionic liquid as catalyst

Two acidic ionic liquids based on 1-benzyl-1H-imidazole have been synthesized and characterized by FT-IR, 1H NMR, 13C NMR and CHNS analyses. The ionic liquids have been used for transesterification of Nigella sativa seed oil as newer sources of oil with methanol. We determined relative fatty acid content, iodine and saponification values of seed oil and estimated cetane number of produced biodiesel based on the chemical composition of oil. Also, the effect of reaction temperature, type and amount of catalyst, molar ratio and reaction time were investigated. The results show that the ILH2 ionic liquid has the higher catalytic activity under the optimized reaction conditions. Thus, this ionic liquid is able to catalyze the transesterification of N. sativa seed oil to its methyl esters in 6h with yields of more than 93%. The catalytic activity of ILH2 for the transesterification of other vegetable oils and alcohols has also been studied.

Fatty acid variability in three medicinal herbs of Panaxspecies

BackgroundFatty acid profiling has been widely used in the bacteria species identification, we hypothesized that fatty acid characteristics might discriminate the Panax herbs according to species. To test the hypothesis, fatty acids of Panax species, including Panax ginseng, Panax notoginseng and Panax quinquefolius, were characterized and compared using gas chromatography–mass spectrometry (GC-MS) followed by multivariate statistical analysis.ResultsThe content of investigated 11 fatty acids, including myristic acid, pentadecanoic acid, palmitic acid, palmitoleic acid, heptadecanoic acid, stearic acid, oleic acid, linoleic acid, α-linolenic acid, arachidic acid and eicosadienoic acid, obviously varied among three species, suggesting each species has its own fatty acid pattern. Principal component analysis and hierarchical clustering analysis according to the absolute and relative contents of fatty acids, showed that 30 tested samples could be clearly differentiated according to the species.ConclusionsThese findings demonstrated that GC-MS-based fatty acid profiling coupled with multivariate statistical analysis provides reliable platform to classify these three Panax species, which is helpful for ensuring their safety and efficacy.

Physicochemical properties of lacquer berries and decolorization of lacquer wax by physical adsorption and UV irradiation

Physicochemical properties of No.1 - No.6 lacquer berries were investigated from different origins. The Japan Showafuku (No.1) was the best cultivar of Rhus succedaneum, the size of the berry of it was near 3 - 4 folds, which was bigger than the Chinese cultivars (No.4 - No.6) of Rhus vernicifera et al. It had more than 5% ~ 10% of lacquer wax in pericard, and contained less than 6% - 8% of lacquer oil in seed. No.1 had lower acid value (A.V) and iodine value (I.V); the key factors for this were cultivar and its growing environment. The principal constituents of lacquer waxes of No.1 - No.6 were triglycerides of fatty acids with total saturated fatty acids (TSFA) of 75% - 82.7%, total unsaturated fatty acids (TUSFA) of 15.1% - 20%, and total dibasic acids (TDBA) of 5%. The CIEL a b system and Hunter whiteness formula were used to evaluate the bleaching effect on lacquer wax by physical adsorption and ultraviolet (UV) irradiation. The optimal conditions of physical decoloration were determined for activated carbon: kieselguhr = 3:2 (g/g) as adsorbent, a ratio of 1:20 (g/mL) for lacquer wax to petroleum ether, bleaching 30 min at 80?C. UV light achieved a good bleaching effect irradiated at 60?C for 60 hrs. UV irradiation definitely changed relative contents of fatty acids, TUSFA and TDBA decreased from 19.617% to 11.022% and 4.379% to 2.017% respectively, while TSFA could be raised from 76.462% to 86.077%, however, the mechanism of UV irradiation was still unclear and should be investigated in the future.