Long-chain free fatty acids from Momordica cochinchinensis leaves as attractants to its insect pest,Aulacophora foveicollis Lucas (Coleoptera: Chrysomelidae)

Extraction, thin layer chromatography, and gas chromatography–mass spectrometry of young, mature, and senescent leaves of Momordica cochinchinensis Spreng revealed 13 free fatty acids, representing a total of 82.29, 91.30, and 68.52% of fatty acids in young, mature, and senescent leaves, respectively. Palmitic acid was the predominant fatty acid followed by stearic acid in three types of leaves. The free fatty acids from young, mature, and senescent leaves attracted female Aulacophora foveicollis Lucas (Coleoptera: Chrysomelidae) at the minimal concentrations of 4, 2, and 8 μg, respectively; whereas the mixtures of synthetic fatty acids mimicking free fatty acids of young, mature, and senescent leaves showed attraction at the minimal concentrations of 4, 2, and 10 μg, respectively, in Y-shaped glass tube olfactometer bioassay under laboratory condition. The results indicate that A. foveicollis may employ long-chain free fatty acids as an olfactory cue for host location. The individual synthetic fatty acids mimicking the proportions detected in three types of leaves were also evaluated through olfactometer bioassay. Only synthetic palmitic acid at the minimal amount of 2.17 μg attracted the insect. A synthetic blend of fatty acids mimicking 8 μg free fatty acid concentration of mature leaves or an amount of 5.42 μg palmitic acid produced the highest attraction of the insect. Hence 5.42 μg palmitic acid might be used for insect pest management program such as baited traps.     

Optimization of extraction method for LC–MS based determination of phenolic acid profiles in different Impatiens species

The main aim of presented study was the comparison of various extraction methods for the quantitative and qualitative analysis (LC-ESI–MS/MS) of phenolic acids present in extracts obtained from leaves, flowers, and roots of Impatiens glandulifera. The accelerated solvent extraction (ASE) at three temperature ranges (80° C, 100° C, and 120° C), ultrasound assisted extraction (USAE) at 60° C, and traditional extraction in Soxhlet apparatus were used. Taking into account the extraction yield, and the diversity of the individual compounds, ultrasound assisted extraction proved to be the most efficient method, and it was used to determine the content of phenolic acids in leaves of four other Impatiens species, including I. balsamina, I. noli-tangere, I. parviflora, and I. walleriana. Eleven phenolic acids were identified in all examined species. These were protocatechuic, gentisic, 4- hydroxybenzoic, vanillic, trans-caffeic, syringic, trans-p-coumaric, trans- and cis-ferulic, salicylic, and 3-hydroxycinnamic acids. In the extract from the leaves of I. balsamina and I. walleriana, gallic and cis-p-coumaric acids were found additionally. The most abundant compounds in all examined extracts were protocatechuic and 3-hydroxycinnamic acids. The latest acid was found in the highest yield in I. noli-tangere (266.12 μg/g DW). In the leaves of I. glandulifera a great amount of 4-hydroxybenzoic (41.44 μg/g DW), vanillic (61.50 μg/g DW), and trans-p-coumaric (58.42 μg/g DW) acids was also observed. Our results indicate that protocatechuic, 4-hydroxybenzoic, vanillic, trans-p-coumaric, trans-ferulic, and 3-hydroxycinnamic acids were most characteristic of Impatiens species.Additionally, various phenolic-rich extracts from leaves, flowers, and roots of Impatiens glandulifera were tested for antioxidant activity. The highest antiradical activity was detected for roots using Soxhlet extraction (EC50 = 0.055 mg [DE/ml]).The study demonstrated that members of the genus Impatiens, and in particular Impatiens glandulifera, and Impatiens noli-tangere, contain significant amounts of phenolic acids. In addition, extracts from various parts of I. glandulifera could be interesting as novel sources of natural antioxidants.     

Olfactory responses of Epilachna dodecastigma (Coleoptera: Coccinellidae) to long-chain fatty acids from Momordica charantia leaves

Extraction, thin-layer chromatography and gas chromatography–mass spectrophotometry analyses revealed the presence of 12, 13, and 12 fatty acids in young, mature, and senescent leaves of Momordica charantia L., representing 87.30, 95.25, and 83.11 % of the total fatty acids, respectively. The proportion of saturated fatty acids was highest in senescent leaves (78.60 %) followed by young leaves (69.42 %) and mature leaves (48.92 %), with the balance accounted for by unsaturated fatty acids. Palmitic acid was the predominant saturated fatty acid in the three types of leaves, whereas alpha-linolenic acid was the predominant unsaturated fatty acid. The fatty acids from young, mature, and senescent leaves followed by the application of a synthetic mixture of fatty acids that was comparable to the natural fatty acids found in the three types of leaves, elicited the attraction of the female insect Epilachna dodecastigma (Coleoptera: Coccinellidae) at 50–200, 50–200, and 100–200 μg/ml concentrations, respectively, in a Y-shaped glass tube olfactometer bioassay. Individual synthetic fatty acids were also evaluated by the olfactometer bioassay at concentrations comparable to the proportions detected in the three types of leaves. Individual synthetic palmitic acid, stearic acid, oleic acid, linoleic acid, and alpha-linolenic acid at 58.24, 13.96, 29.40, 30.31, and 29.76 μg, respectively, attracted the insect. A synthetic blend of 79.13, 10.57, 29.40, 30.31, and 36.33 μg of palmitic, stearic, oleic, linoleic, and alpha-linolenic acids, respectively, which is the proportion present in a 200 μg/ml concentration of fatty acids of mature leaves, or of 116.49, 13.96, and 29.76 μg of palmitic, stearic and alpha-linolenic acids, respectively, which is the proportion present in a 200 μg/ml concentration of natural fatty acids of young leaves, served as attractants for E. dodecastigma.     

Omega-3 index determined by gas chromatography with electron impact mass spectrometry

Omega-3 index is a relatively new concept, defined as the sum of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) expressed as a percentage of the total fatty acids in red blood cell membranes. This index reflects medium to long-term intake of omega-3 polyunsaturated fatty acids and could be a useful tool in epidemiological studies. The standard technique used for fatty acid analysis and quantification has been gas chromatography (GC) with flame ionization detection. This method is robust and has good precision and sensitivity. However, a major disadvantage is inability to confirm spectrometrically the identity of fatty acids detected, which is important especially in complex biological samples. The current study measures omega-3 index in 12 healthy human volunteers using GC-mass spectrometry (MS). Both the intra-assay and day-to-day variations were well within 5% with linearity of response extending to a concentration of 250 μg/ml (830 μmol/L) of EPA. The limit of detection of EPA was 0.36 μg/ml (1.2 μmol/L). About 25 fatty acids were consistently detected in red blood cells from healthy volunteers including cis and trans isomers. The omega-3 index ranged from 2.4% to 6.2% among the 12 volunteers examined and there was no difference between samples taken in the fasting and postprandial states. EPA and DHA concentrations ranged from 3.53 to 105.89 μg/ml (11.7–350 μmol/L) and 12.19 to 214.42 μg/ml (37.1–652.7 μmol/L), respectively. Thus a GC–MS method has been developed for measuring the omega-3 index. Further studies are required to determine the role of this index as a predictor of disease.     

2-Hexadecynoic acid inhibits plasmodial FAS-II enzymes and arrests erythrocytic and liver stage Plasmodium infections

Acetylenic fatty acids are known to display several biological activities, but their antimalarial activity has remained unexplored. In this study, we synthesized the 2-, 5-, 6-, and 9-hexadecynoic acids (HDAs) and evaluated their in vitro activity against erythrocytic (blood) stages of Plasmodium falciparum and liver stages of Plasmodium yoelii infections. Since the type II fatty acid biosynthesis pathway (PfFAS-II) has recently been shown to be indispensable for liver stage malaria parasites, the inhibitory potential of the HDAs against multiple P. falciparum FAS-II (PfFAS-II) elongation enzymes was also evaluated. The highest antiplasmodial activity against blood stages of P. falciparum was displayed by 5-HDA (IC₅₀ value 6.6 μg/ml), whereas the 2-HDA was the only acid arresting the growth of liver stage P. yoelii infection, in both flow cytometric assay (IC₅₀ value 2-HDA 15.3 μg/ml, control drug atovaquone 2.5 ng/ml) and immunofluorescence analysis (IC₅₀ 2-HDA 4.88 μg/ml, control drug atovaquone 0.37 ng/ml). 2-HDA showed the best inhibitory activity against the PfFAS-II enzymes PfFabI and PfFabZ with IC₅₀ values of 0.38 and 0.58 μg/ml (IC₅₀ control drugs 14 and 30 ng/ml), respectively. Enzyme kinetics and molecular modeling studies revealed valuable insights into the binding mechanism of 2-HDA on the target enzymes. All HDAs showed in vitro activity against Trypanosoma brucei rhodesiense (IC₅₀ values 3.7–31.7 μg/ml), Trypanosoma cruzi (only 2-HDA, IC₅₀ 20.2 μg/ml), and Leishmania donovani (IC₅₀ values 4.1–13.4 μg/ml) with generally low or no significant toxicity on mammalian cells. This is the first study to indicate therapeutic potential of HDAs against various parasitic protozoa. It also points out that the malarial liver stage growth inhibitory effect of the 2-HDA may be promoted via PfFAS-II enzymes. The lack of cytotoxicity, lipophilic nature, and calculated pharmacokinetic properties suggests that 2-HDA could be a useful compound to study the interaction of fatty acids with these key P. falciparum enzymes.     

Isolation and characterization of ellagitannins as the major polyphenolic components of Longan (Dimocarpus longan Lour) seeds

Longan (Dimocarpus longan Lour, syn. Euphoria longan Lam.) represents an important fruit in Northern Thailand and has significant economic impact. The fruit is either consumed fresh or as commercially prepared dried and canned products. The canning industry in Thailand produces considerable quantities of waste products, in particular Longan seeds. Because these seeds may be an exploitable source of natural phenolic antioxidants, it was of interest to identify, purify and quantitate the major potential antioxidant phenolics contained therein. The polyphenolic fraction from ground Longan seeds was obtained by extraction with methanol after delipidation with hexane. The hexane extract contained predominantly long-chain fatty acids with major contributions from palmitic (35%) and oleic (28%) acids. The polyphenolic fraction (80.90 g/kg dry weight) was dominated by ellagic acid (25.84 g/kg) and the known ellagitannins corilagin (13.31 g/kg), chebulagic acid (13.06 g/kg), ellagic acid 4-O-α-l-arabinofuranoside (9.93 g/kg), isomallotinic acid (8.56 g/kg) and geraniin (5.79 g/kg). Structure elucidation was performed with mass spectrometry and complete assignment of ¹H and ¹³C NMR signals. The methanol extracts exhibited strong antioxidant capacities with an IC₅₀ of 154 μg/ml for reactive oxygen species attack on salicylic acid and 78 μg/ml for inhibition of xanthine oxidase in the hypoxanthine/xanthine oxidase assay. The extracts were less effective in the 2-deoxyguanosine assay (IC₅₀ = 2.46 mg/ml), indicating that gallates along with ellagic acid and its congeners exert their potential antioxidant effects predominantly by precipitation of proteins such as xanthine oxidase. This was confirmed for the pure compounds gallic acid, methyl gallate, ellagic acid and corilagin.     

Effect of serum albumin supplementation on in vitro capacitation and fertilization of caprine oocytes

The aim of the investigation was to study the effect of purity and the type of serum albumin on in vitro fertilization (IVF) and cleavage rate of in vitro matured goat oocytes. Ovaries were collected from the local abattoir and transported within 4 h to the laboratory in warm saline (37 °C) containing 100 IU penicillin-G and 100 μg streptomycin sulfate per ml. A total of 2509 cumulus oocyte complexes (COCs) were collected from 1313 ovaries. Oocytes were matured in TCM-199 medium containing FSH (5 μg/ml), LH (5 μg/ml) and estradiol-17β (1 μg/ml), supplemented with 20% fetal bovine serum at 38.5 °C and 5% CO₂ in an incubator under humidified air for 27 h. After 27 h of in vitro maturation (IVM), oocytes were denuded, washed and randomly divided into 4 groups. Group 1 consisted of in vitro matured oocytes (n = 627) co-incubated with sperm in a 50 μl drop of TALP medium containing a 6 mg/ml crystalline bovine serum albumin (BSA) fraction V and 10 μg/ml heparin. Group 2 was comprised of in vitro matured oocytes (n = 470), co-incubated with sperm in a 50 μl drop of TALP medium containing 3 mg/ml crystalline BSA fraction V, 10% estrous goat serum and 10 μg/ml heparin. Group 3 was comprised of in vitro matured oocytes (n = 489) co-incubated with sperm in a 50 μl drop of TALP medium containing a 6 mg/ml fatty acid free BSA and 10 μg/ml heparin. Group 4 consisted of in vitro matured oocytes (n = 422) co-incubated with sperm in a 50 μl drop of TALP medium containing 20% estrous goat serum and 10 μg/ml heparin. After 18 h of co-incubation, the oocyte–sperm mixture was washed in the culture medium 15–20 times and cultured in 50 μl EDM. Cleavage of the in vitro fertilized oocytes were recorded 48 h post-insemination under an inverted phase contrast microscope. The average oocyte recovery rate/ovary and maturation rate was 1.91% and 80.03%, respectively. The cleavage rate in Group 1, Group 2, Group 3 and Group 4 was 1.59%, 8.93%, 11.86% and 35.30%, respectively. It could be concluded that the use of fatty acid free albumin resulted in a significantly higher (P < 0.05) cleavage rate, compared to unmodified albumin, and the supplementation of 20% estrous goat serum in the fertilization medium, significantly (P < 0.05) increased the cleavage rate of in vitro matured goat oocytes, compared to defatted albumin.     

Free fatty acids from the weed,Polygonum orientale leaves for attraction of the potential biocontrol agent,Galerucella placida (Coleoptera: Chrysomelidae)

Extraction, thin layer chromatography and gas chromatography-mass spectrometry of leaf surface waxes of Polygonum orientale L. (Polygonaceae) weed revealed 11, 15 and 11 free fatty acids in young, mature and senescent stages. Oleic acid was the predominant in young leaves (5950 ± 111 µg); whereas palmitic acid was the predominant fatty acids, representing 4247.5 ± 23 and 6644 ± 110 µg in mature and senescent leaves, respectively. Both tridecanoic and heneicosanoic acids were not detected in young and senescent leaves, and myristic and heptadecanoic acids were not identified in young leaves; whereas lauric and nonadecanoic acids were not detected in senescent leaves. The free fatty acids from young, mature and senescent weed leaves, and the mixtures of synthetic fatty acids mimicking free fatty acids of three types of weed leaves attracted female Galerucella placida (Coleoptera: Chrysomelidae) at the minimal amounts of 2, 1 and 2 leaf equivalent free fatty acids, respectively, in Y-shaped glass tube olfactometer bioassays under laboratory conditions. Individual synthetic pentadecanoic, palmitoleic, stearic, nonadecanoic and docosanoic acids at 44.82, 9.91, 92.22, 18.33 and 15.88 µg, respectively, elicited attraction of the insect. A synthetic blend of 3.59, 7.89, 44.82, 9.91, 32.31, 18.33 and 15.88 µg of lauric, myristic, pentadecanoic, palmitoleic, heptadecanoic, nonadecanoic and docosanoic acids, respectively, indicated highest attraction of the insect.     

Influence of organic systems on milk fatty acid profile and CLA in goats

The effect of organic system on the fatty acid profile of milk and CLA content was evaluated using 30 pregnant pluriparous goats, divided into two homogeneous groups (S and O) of 15 goats each. Group S was housed in a stable and received alfalfa hay as forage, while group O was raised according EC Regulation 834/2007 and led to pasture. After the kids weaning, goats were milked twice a day for 5 months. Daily milk yield was recorded and, monthly, representative milk samples from the two daily milkings were analysed for chemical and fatty acid profile. Average milk yield did not differ statistically between the groups. The goats of the O group had significantly higher fat content in milk than those of group S (65.9 g/day vs. 54.3 g/day, P < 0.01). Among milk fatty acids, organic system significantly affected the percentages of C18:1 c9, C18:1 t11, linoleic acid, alpha-linolenic acid, monounsaturated fatty acid and polyunsaturated fatty acid. Organic system highly influenced the c9 t11 conjugated linoleic acid (CLA) (0.810 g/100 g of fat vs. 0.542 g/100 g of fat, for groups O and S, respectively, P < 0.01), t10 c12 CLA (0.041 g/100 g of fat vs. 0.024 g/100 g of fat, for groups O and S, respectively, P < 0.01) and ∑CLA (0.87 g/100 g of fat vs. 0.58 g/100 g of fat for groups O and S, respectively, P < 0.01) concentrations of milk.     

N − 3PUFA differentially modulate palmitate-induced lipotoxicity through alterations of its metabolism in C2C12 muscle cells

Excessive energy intake leads to fat overload and the formation of lipotoxic compounds mainly derived from the saturated fatty acid palmitate (PAL), thus promoting insulin resistance (IR) in skeletal muscle. N − 3 polyunsaturated fatty acids (n − 3PUFA) may prevent lipotoxicity and IR. The purpose of this study was to examine the differential effects of n − 3PUFA on fatty acid metabolism and insulin sensitivity in muscle cells. C2C12 myotubes were treated with 500 μM of PAL without or with 50 μM of alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA) or docosahexaenoic acid (DHA) for 16 h. PAL decreased insulin-dependent AKT activation and glucose uptake and increased the synthesis of ceramides and diglycerides (DG) derivatives, leading to protein kinase Cθ activation. EPA and DHA, but not ALA, prevented PAL-decreased AKT activation but glucose uptake was restored to control values by all n − 3PUFA vs. PAL. Total DG and ceramide contents were decreased by all n − 3PUFA, but only EPA and DHA increased PAL β-oxidation, decreased PAL incorporation into DG and reduced protein kinase Cθ activation. EPA and DHA emerge as better candidates than ALA to improve fatty acid metabolism in skeletal muscle cells, notably via their ability to increase mitochondrial β-oxidation.     

Primer caso de fungemia asociada a catéter por Candida nivariensis en la Península Ibérica

BackgroundIn recent years the incidence of candidemia caused by non-albicans Candida species has been increasing. Two cryptic species have been described within the Candida glabrata complex, Candida nivariensis and Candida bracarensis, which may be troublesome in laboratory identification and have lower susceptibility to fluconazole.AimsTo describe the first isolation of C. nivariensis in the Iberian Peninsula from a patient suffering from a catheter-related fungemia.Case reportAn 81-year-old man was hospitalized for surgical treatment of an intestinal fistula that was associated to a severe malnutrition. Cultures of the patient's central venous catheter tip and blood yielded white colonies in BD CHROMagar Candida^® medium, which could not be identified by conventional microbiological methods. Although intravenous fluconazole was administered, blood cultures continued being positive 5 days later. The MIC values of the isolate were as follows: 1 μg/ml for amphotericin B, 0.015 μg/ml for anidulafungin, 0.125 μg/ml for caspofungin, 0.015 μg/ml for micafungin, 4 μg/ml for fluconazole, 0.25 μg/ml for itraconazole, 0.25 μg/ml for posaconazole, and 0.03 μg/ml for voriconazole. Antifungal treatment was changed to intravenous caspofungin for 2 weeks. The intestinal fistula was surgically treated. There was no evidence of relapse during the following month, and the patient was discharged. The isolate was identified as C. nivariensis based on DNA sequencing of the ITS regions of rRNA.ConclusionsC. nivariensis should be regarded as an emerging pathogen which requires molecular methods for a definitive identification. Our patient was successfully treated with caspofungin.     

Isolation of antioxidant constituents from Combretum apiculatum subsp. apiculatum

Species of the family Combretaceae are used extensively in traditional medicine against inflammation and infections, and although antibacterial activity has been reported in non-polar extracts, further rationale for the widespread use of the Combretaceae is expected to exist. Methanol extracts of leaves of ten different Combretum species were evaluated for antioxidant activity by spraying TLC chromatograms of each leaf extract with 2,2-diphenyl-1-picrylhydrazyl (DPPH). Compounds with antioxidant activity were detected by bleaching of the purple DPPH colour. Leaf extracts of Combretum apiculatum subsp. apiculatum had the most antioxidant compounds. This species was consequently selected for phytochemical investigation. A DPPH assay-directed fractionation of the leaf extracts of C. apiculatum led to the isolation of four antioxidant compounds from the ethyl acetate and butanol soluble fractions. The structures of the compounds were determined by spectroscopic analyses (¹H-NMR, ¹³C-NMR and MS) and identified as: cardamonin (1), pinocembrin (2), quercetrin (3) and kaempferol (4). In a quantitative antioxidant assay, the more polar fractions (ethyl acetate and butanol) obtained by solvent–solvent fractionation had the highest antioxidant activity among the solvent fractions obtained from C. apiculatum, with EC₅₀ values of 3.91 ± 0.02 and 2.44 ± 0.02 μg/ml respectively. Of the four isolated compounds, quercetrin (4) and kaempferol (3) had the strongest antioxidant activity, with EC₅₀ values of 11.81 ± 85 and 47.36 ± 0.03 μM respectively. Cardamonin (1) and pinocembrin (2) did not demonstrate strong activity. L-ascorbic acid was used as standard antioxidant agent (EC₅₀ = 13.37 ± 0.20 μM or 2.35 μg/ml). The cytotoxicity of cardamonin and pinocembrin was evaluated on Vero kidney cells using the MTT (3-(4,5-dimethylthiazol)-2,5-diphenyl tetrazolium bromide) assay with berberine as positive control. At concentrations higher than 50 μg/ml of cardamonin or pinocembrin, the cells were not viable. Cardamonin was more toxic (LC₅₀ = 1.97 μg/ml) than pinocembrin (LC₅₀ = 29.47 μg/ml) and even the positive control, berberine (LC₅₀ = 12.35 μg/ml).     

Enzymatic purification of dihomo-γ-linolenic acid from Mortierella single-cell oil

Purification of dihomo-γ-linolenic acid (20:3n−6; DGLA) from a single-cell oil containing 39 wt.% DGLA was attempted. The process comprised: (i) non-selective hydrolysis of the oil to prepare a mixture of free fatty acids (FFAs); (ii) urea adduct fractionation of the FFA mixture to remove saturated fatty acids; and (iii) repeated selective esterification of the resulting mixture with two kinds of lipases. In the first step, Candida rugosa lipase (Lipase-OF from Meito Sangyo Co. Ltd., Aichi, Japan) was the most effective for preparation of the FFAs from the oil; 99% hydrolysis was achieved by the reaction at 40 °C for 72 h. Urea adduct fractionation of the FFA mixture removed almost completely behenic and lignoceric acids, and the content of DGLA increased from 39 to 55 wt.%. The FFAs were esterified with 2 mol equivalent of lauryl alcohol (LauOH) using C. rugosa lipase (Lipase-AY from Amano Enzyme Inc., Aichi, Japan). In consequent, DGLA was enriched to 86 wt.% in the unesterified FFA fraction. To further increase the content of DGLA, the esterification was repeated using the same lipase. Accordingly, the content of DGLA increased to 91 wt.%, but the preparation was contaminated with 3.3 wt.% γ-linolenic acid. This contaminant was removed finally by selective esterification of the FFAs with 2 mol equivalent of LauOH using Pseudomonas aeruginosa lipase. A series of procedures purified DGLA to 95 wt.% in a yield of 51% of the initial content in the single-cell oil.     

New antimicrobial anthraquinone 6,61-bis (1,5,7-trihydroxy-3-hydroxymethylanthraquinone) isolated from Streptomyces sp. isolate ERI-26

The present report is about Streptomyces sp. isolate ERI-26 isolated from the soil sample of Nilgiri forest, Western Ghats. The methanol extract of ERI-26 showed good antimicrobial activity against tested microbes. The antimicrobial novel anthraquinones were purified by bioactivity-guided fractionation using a silica gel column and preparative HPLC. The compound was characterized and identified by UV, IR, NMR and MASS spectral data. The compound named as 6,6¹-bis (1,5,7-trihydroxy-3-hydroxymethylanthraquinone), showed significant antimicrobial activities against tested microbes. The isolated compound inhibited the tested bacterial growth, Staphylococcus aureus at 62.5 μg/ml, Staphylococcus epidermidis at 15.62 μg/m, Bacillus subtilis at 62.5 μg/ml, fungi; Trichophyton mentagrophytes at 15.62 μg/m Trichophyton simii at 15.62 μg/ml, Aspergillus niger at. 7.81 μg/ml, Aspergiller flavus at 3.90 μg/ml, Trichophyton rubrum 296 at 62.5 μg/ml, T. rubrum 57/01 at 7.81 μg/ml, Magnaporthe grisea at 15.62 μg/ml. and Botrytis cinerea at 3.90 μg/ml. Isolated anthraquinone compound and its antimicrobial activity were newly reported.     

Production of microbial lipid by Cryptococcus curvatus on rice straw hydrolysates

Microbial biolipids/biodiesels derived from volatile fatty acids (VFAs) can be a valuable alternative to plant oils if optimum fermentation conditions are determined. VFAs were used for cell mass and microbial lipid production by Cryptococcus curvatus. The lipid content in the cells increased up to 48% and 28% in batch cultures with the use of 20 g/L glucose and 6 g/L of VFAs as the carbon source, respectively. In this study, C. curvatus used VFAs as a carbon source via anaerobic digestion of rice straw hydrolysates. VFAs produced from rice straw resulted in yield of 0.43 g VFAs/g substrate and 40% higher specific growth rate(0.305 h⁻¹) than synthetic VFAs. The highest fatty acid composition observed was C18:1, was obtained using glucose and VFAs as the carbon source to yield a cetane number of 56–59, which is suitable for biodiesel production. The cost of microbial lipids was estimated to be 0.30–1.15 USD/L given 0–150 USD/ton of VFAs cost for a yield of 0.17 g/g of lipids. Thus, VFAs can be a suitable carbon source for economical biodiesel production.     

Effects of nitrogen concentration and media replacement on cell growth and lipid production of oleaginous marine microalga Nannochloropsis oceanica DUT01

Cell growth and lipid production of a marine microalga Nannochloropsis oceanica DUT01 were investigated, and fresh medium replacement with different ratios to promote long term cell growth and lipid accumulation was also tested. The highest lipid content reached 64% in nitrogen deplete f/2 medium containing 37.5 mg/L NaNO₃ combined with 1/5 fresh medium replacement, however, the highest lipid titer (0.6 g/L) and lipid productivity (31 mg/L/d) were achieved using BG11 medium containing 1.5 g/L NaNO₃, taking advantage of 1/5 fresh medium replacement as well, which corresponded to the maximum biomass production of 1.4 g/L, highlighting the importance of high biomass accumulation for efficient lipid production. When biomass compositions were monitored throughout the culture, decreased protein content was found to be coupled with increased lipid production, whereas relatively stable carbohydrate content was observed. The fatty acids in the lipid of N. oceanica DUT01 comprise over 65% saturated fatty acids and monounsaturated acids (i.e. palmitic acid (C16:0) and oleic acid (C18:1)), suggesting that N. oceanica DUT01 is a promising candidate for biodiesel production. Interestingly, very high content of hexadecadienoic acid (C16:2, about 26–33%) was produced by DUT01, which distinguished this microalga with other microalgae strains reported so far.     

Synthesis and biological evaluation of new potential inhibitors of N-acylethanolamine hydrolyzing acid amidase

N-Acylethanolamines, including N-palmitoyl-ethanolamine (PEA), are hydrolyzed to the corresponding fatty acids and ethanolamine by fatty acid amide hydrolase (FAAH). Recently, N-acylethanolamine-hydrolyzing acid amidase (NAAA) was identified as being able to specifically hydrolyze PEA. In order to find selective and effective inhibitors of this enzyme, we synthesized and screened several amides, retroamides, esters, retroesters and carbamates of palmitic acid (1–21) and esters with C15 and C17 alkyl chains (22–27). Cyclopentylhexadecanoate (13) exhibited the highest inhibitory activity on NAAA (IC₅₀ = 10.0 μM), without inhibiting FAAH up to 50 μM. Compound 13 may become a useful template to design new NAAA inhibitors.     

Anti adipogenic activity of Aegle marmelos Correa

In continuation of evaluating the anti-obesity effect of Aegle marmelos, we have screened the n-hexane, dichloro methane (DCM), ethyl acetate (EtOAc) and methanol (MeOH) extracts of the leaves at the concentration of 25, 50, 75 and 100 μg/ml for adipogenesis inhibition in the adipocytes. Nile red staining with the help of fluorometry was used as indicator of the antiobesity activity. The most active DCM extract showed the 33.98 ± 3.55% lipid content at 100 μg/ml and was selected for the further isolation. 14 compounds were isolated from DCM extract of A. marmelos leaves. The compounds were screened for the adipogenesis inhibition at 50 and 100 μM concentrations. Out of the 14 compounds, halfordinol, ethyl ether aegeline and esculetin were showing 10.04 ± 0.52, 16.29 ± 0.85 and 25.09 ± 1.31% lipid content respectively at 100 μM. We hereby report the adipogenesis inhibition by A. marmelos as one of the pathway for its antiobesity effect.     

Antiviral activity of raoulic acid from Raoulia australis against Picornaviruses

RNA viruses are a major source of respiratory diseases worldwide. The lack of effective therapeutical treatment underlines the importance of research for new antiviral compounds. Raoulic acid is a principal ingredient of the plant Raoulia australis Hook. F. Antiviral assay using cytopathic effect (CPE) reduction method showed that raoulic acid possessed strong antiviral activity against human rhinovirus 2 (HRV2) with a 50% inhibition concentration (IC₅₀) value of less than 0.1 μg/ml, human rhinovirus 3 (HRV3) with a IC₅₀ value of 0.19 μg/ml, coxsackie B3 (CB3) virus with IC₅₀ values of 0.33 μg/ml, coxsackie B4 (CB4) virus with IC₅₀ values of 0.40 μg/ml, and enterovirus 71 (EV71) virus with IC₅₀ values of less than 0.1 μg/ml. However, the compound did not possess antiviral activity against influenza A (Flu A/PR, Flu A/WS, H1N1) and B viruses at four concentrations ranging from 0.1 to 100 μg/ml.     

Carbon nanotube based betulin formulation shows better efficacy against Leishmania parasite

We report a novel antileishmanial formulation of betulin (BET) attached to functionalized carbon nanotubes (f-CNTs). We conjugated betulin, a pentacyclic triterpenoid secondary metabolite, to carboxylic acid chains on f-CNTs to obtain BET attached functionalized carbon nanotubes (f-CNT-Bet). The drug release profile demonstrated a fairly slow release of BET. The in-vitro cytotoxicities of BET, f-CNT and f-CNT-BET on J774A.1 macrophage cell line were 211.05 ± 7.14 μg/ml; 24.67 ± 3.11 μg/ml and 72.63 ± 6.14 μg/ml, respectively. The IC₅₀ of BET and f-CNT-BET against intracellular Leishmania donovani amastigotes were 8.33 ± 0.41 μg/ml and 0.69 ± 0.08 μg/ml, respectively. The results demonstrate better antileishmanial efficiency of f-CNT-BET formulation than BET alone and with no significant cytotoxicity observed on host cells.