Efficient isolation of anthraquinone-derivatives from Trichoderma harzianum ETS 323

Anthraquinone-derivatives, chrysophanol and pachybasin, were purified by a silica column chromatography with two different solvent systems from Trichoderma harzianum ETS 323. The fungus was incubated in sugarcane bagasse solid medium at room temperature without rotation. Structure of chrysophanol was solved by X-ray diffraction and pachybasin by NMR spectra. About 233+/-13 mg of pure chrysophanol and 773+/-40 mg of pure pachybasin were recovered per kg of solid cultural medium, with yields 1.7+/-0.2% and 5.6+/-0.5%, respectively.     

Knipholone cyclooxanthrone and an anthraquinone dimer with antiplasmodial activities from the roots of Kniphofia foliosa

A new phenylanthrone, named knipholone cyclooxanthrone and a dimeric anthraquinone, 10-methoxy-10,7′-(chrysophanol anthrone)-chrysophanol were isolated from the roots of Kniphofia foliosa together with the rare naphthalene glycoside, dianellin. The structures were determined by NMR and mass spectroscopic techniques. The compounds showed antiplasmodial activities against the chloroquine-resistant (W2) and chloroquine-sensitive (D6) strains of Plasmodium falciparum with 10-methoxy-10,7′-(chrysophanol anthrone)-chrysophanol being the most active with IC₅₀ values of 1.17 ± 0.12 and 4.07 ± 1.54 μg/ml, respectively.     

Vanillin bioproduction from alkaline hydrolyzate of corn cob by Escherichia coli JM109/pBB1

Hydrolysis of corn cob performed for 6 h with 0.5 N NaOH at solid/liquid ratio of 0.084 g/g allowed obtaining a hydrolyzate containing 1171 ± 34 mg/l ferulic acid and 2156 ± 63 mg/l p-coumaric acid that was used as a medium for vanillin bioproduction by the engineered strain Escherichia coli JM109/pBB1. Aiming at maximizing vanillin bioproduction, the effects of medium heat sterilization, one-stage or two-stage pre-cultivation, adaptation of the microorganism to the hydrolyzate and inoculum biomass level were investigated. Biomass pre-cultivated once in unsterilized hydrolyzate was able to effectively convert ferulic and p-coumaric acids to a mixture of vanillin, vanillic acid and vanillyl alcohol provided with the typical vanilla flavor. At initial biomass concentration of 0.5 g_DM/l, maximum values of vanillin concentration (239 ± 15 mg/l), vanillin yield on consumed ferulic acid (0.66 ± 0.03 mol/mol) and vanillin volumetric productivity (10.9 ± 0.7 mg/lh) were obtained after 22 h.     

Novel biotransformation process of podophyllotoxin to produce podophyllic acid and picropodophyllotoxin by Pseudomonas aeruginosa CCTCC AB93066, Part II: Process optimization

This work optimized the novel biotransformation process of podophyllotoxin to produce podophyllic acid by Pseudomonas aeruginosa CCTCC AB93066. Firstly, the biotransformation process was significantly affected by medium composition. 5 g/l of yeast extract and 5 g/l of peptone were favorable for podophyllic acid production (i.e. 25.3 ± 3.7 mg/l), while not beneficial for the cell growth of P. aeruginosa. This indicated that the accumulation of podophyllic acid was not corresponded well to the cell growth of P. aeruginosa. 0 g/l of sucrose was beneficial for podophyllic acid production (i.e. 34.3 ± 3.9 mg/l), which led to high podophyllotoxin conversion (i.e. 98.2 ± 0.1%). 1 g/l of NaCl was the best for podophyllic acid production (i.e. 47.6 ± 4.0 mg/l). Secondly, the production of podophyllic acid was significantly enhanced by fed-batch biotransformation. When each 100 mg/l of podophyllotoxin was added to the biotransformation system after 4, 10 and 25 h of culture, respectively, podophyllic acid concentration reached 99.9 ± 12.3 mg/l, enhanced by 284% comparing to one-time addition (i.e. 26.0 ± 2.1 mg/l). The fundamental information obtained in this study provides a simple and efficient way to produce podophyllic acid.     

A novel medium for the production of cephamycin C by Nocardia lactamdurans using solid-state fermentation

In this study, Nocardia lactamdurans NRRL 3802 was explored for the first time for production of cephamycin C by using solid-state fermentation. The effects of various substrates, moisture content, inoculum size, initial pH of culture medium, additional nitrogen source and amino acids were investigated for the maximum production of cephamycin C by N. lactamdurans NRRL 3802 in solid-state fermentation. Subsequently, selected fermentation parameters were further optimized by response surface methodology (RSM). The soybean flour as a substrate with moisture content of 65%, initial pH of culture medium of 6.5 and inoculum size of 10⁹ CFU/ml (2 × 10⁸ CFU/gds) at 28 ± 2 °C after 4 days gave maximum production of 15.75 ± 0.27 mg/gds of cephamycin C as compared to 8.37 ± 0.23 mg/gds before optimization. Effect of 1,3-diaminopropane on cephamycin C production was further studied, which further increased the yield to 27.64 ± 0.33 mg/gds.     

Cyanobacterial biomass as N-supplement to agro-waste for hyper-production of laccase from Pleurotus ostreatus in solid state fermentation

The potential application of dry biomass of a cyanobacterium Anacystis nidulans as a supplement in SSF for the production of laccase from Pleurotus ostreatus was evaluated. Experiments were carried out in solid culture using groundnut shell as a basic substrate supplemented with four independent nitrogen sources (ammonium sulphate, urea, yeast extract and dry powder of cyanobacteria). All the four supplements enhanced the enzyme yield, and yeast extract showed precedence over inorganic nitrogenous sources. However, when dry biomass of A. nidulans was used as an additive to groundnut shell (agricultural residues), it supported maximum cell growth (56.83 ± 5.56 mg/g dry substrate) and laccase production (49.21 ± 4.89 U/g dry substrate). Addition of 1 mM copper salt in the medium containing groundnut shell supplemented with yeast extract gave laccase activity of 32.64 ± 3.4 U/g dry substrate. When dry powder of cyanobacterial biomass was used as N-supplement, laccase production enhanced to 65.42 ± 6.48 U/g dry substrate. In addition to the enhancement to enzyme production inhibitory effects of high concentrations of copper was also diminished in the medium having dry cyanobacterial biomass. This study, forms the first report on the potential application of cyanobacterial biomass as an additive for production of laccase by Pleurotus ostraetus MTCC 1804 in solid state fermentation and has relevance in scale-up production of this fungal enzyme of commercial significance.     

Metabolic control and chronic complications during a 3-year follow-up period in a cohort of type 2 diabetic patients attended in primary care in the Community of Madrid (Spain)

BackgroundOur aim was to analyze both metabolic control and chronic complications of type 2 diabetes mellitus (T2D) patients regularly attended in primary care during a 3 years of follow-up in the Community of Madrid (Spain).MethodsFrom 2007 to 2010 we prospectively included 3268 patients with T2D attended by 153 primary care physicians from 51 family health centers. An prospective cohort study with annual evaluation over 3 years to the same population was performed. We measured the goals of control in diabetic patients and the incidence of chronic complications of diabetes during the study period.ResultsA significant decrease in serum glucose levels (143 ± 42 mg/dl vs 137 ± 43 mg/dl, p < 0.00), HbA1c (7.09 ± 1.2% vs 7.02 ± 1.2%, p < 0.00), total cholesterol (191.4 ± 38 mg/dl vs 181.5 ± 36 mg/dl, p < 0.00), LDL cholesterol (114.7 ± 31 mg/dl vs 105.5 ± 30 mg/dl, p < 0.00) and triglyceride levels (144.5 ± 93 mg/dl vs 138 ± 84 mg/dl, p < 0.00) during study period was documented. On the contrary, a significant elevation in HDL cholesterol levels was observed (49.2 ± 14 mg/dl vs 49.9 ± 16 mg/dl, p < 0.00). The incidence of diabetic complications throughout the study period was low, with a incidence of coronary heart disease of 6.2%, peripheral arterial disease 3%, ischemic stroke 2.8%, diabetic foot 11.2%, nephropathy 5.9%, retinopathy 4.5%, and neuropathy 3%.ConclusionMetabolic control in T2D patients attended in primary care in the Community of Madrid throughout 3 years is adequate and is accompanied by low percent of chronic diabetic complications during this period of follow-up.     

The effect of glucose and maltose concentrations on pyruvate and ascorbate production,antioxidant enzyme activities and LPO levels in Fusarium equiseti

Changes in pyruvate and ascorbate production and antioxidant enzyme activities together with lipid peroxidation levels in Fusarium equiseti were investigated in relation to changes in the concentrations of glucose and maltose as carbon sources in the range of 5–25 g/l in Armstrong Fusarium Medium (AFM). The highest pyruvate concentration obtained at 20 g/l maltose was 67.5 ± 0.69 μg/ml while ascorbic acid reached a maximum value at 25 g/l glucose of 1866±26.1 μg/ml The maximum superoxide dismutas (SOD) activities related to increased pyruvate production were determined in AFM medium containing 20 g/l glucose as 41.49±0.65 and maltose as 61.12±0.8 IU/mg. Catalase (CAT) activity variations showed coherence with SOD activity in a medium containing maltose and reached 219.11±2.8 IU/mg while they were decreased with increasing glucose concentration. glutathione peroxidase (GSH-Px) activities in F. equiseti did not change significantly with glucose and maltose concentration and were determined to be 1.21±0.22 and 1.67±0.15 IU/mg, respectively. Minimum lipid peroxidation levels for each carbon source were determined in both 20 g/l maltose and glucose concentrations as 0.9 and 1.62 nmol MDA/g wet weight.     

Phytochemical and antioxidant properties of unconventional leafy vegetables consumed in southern Africa

Indigenous leafy vegetables possess high horticultural potential based on their long utilisation history by local communities across Africa. Phytochemical and antioxidant properties of 50% aqueous methanol and water extracts of three indigenous as well as two commercial leafy vegetables commonly consumed in southern Africa were evaluated. The total extractable phenolic content was highest for Amarathus dubius (5.16 ± 0.12 mg GAE/g DW) followed by Cleome gynandra (3.94 ± 0.09 mg GAE/g DW). Total flavonoid concentration was highest for A. dubius (3.89 ± 0.28 mg CE/g DW) followed by C. gynandra (2.19 ± 0.11 mg CE/g DW) and Cucurbita maxima (1.55 ± 0.04 mg CE/g DW). No proanthocyanidins were detected in C. maxima and Brassica napus cv Covo whereas low concentrations were recorded in other vegetables. Total saponins were variable across the evaluated extracts, with the highest concentrations recorded for B. napus cv Covo (83.2 ± 16.58 mg DE/g DW). Total iridoid content was highest for C. gynandra (9.14 ± 0.20 mg HE/g DW). More potent DPPH radical scavenging activities were exhibited by 50% aqueous methanol extracts compared to water extracts. A similar trend was observed in the ferric-reducing antioxidant power assay. The antioxidant activity based on the rate of β-carotene bleaching was higher for water extracts compared to 50% aqueous methanol extracts. The indigenous vegetables evaluated in this study had higher levels of phytochemicals and also exhibited more potent antioxidant activity compared to the commercial varieties. These findings not only suggest the importance of the indigenous vegetables in a healthy diet, but also provide a motivation for exploring their horticultural potential.     

Nutritional value of Chlorella vulgaris: Effects of ultrasonication and electroporation on digestibility in rats

Three processed products derived from the green algae C. vulgaris were investigated: (1) spray-dried only (S-DA); (2) spray-dried and electroporated (ES-DA); (3) spray-dried; ultrasonicated treated (US-DA). A nitrogen-balance study was performed. Male growing Wistar rats, housed separately in metabolism cages, were fed the three algal products as the sole protein source at 150 mg N per 100 g of body weight. A control group of rats was fed with casein at a level to give the same protein nitrogen intake. The coefficients of total intestinal tract apparent crude protein digestibility for the different C. vulgaris products were: S-DA = 0.47 ± 0.127% (mean ± S.D.), ES-DA = 0.44 ± 0.075%, US-DA = 0.57 ± 0.137%. Protein efficiency ratio was 1.4 ± 0.3, 1.0 ± 0.5 and 2.1 ± 0.3, respectively. N-balance was 41.86 ± 32.8 mg, 31.3 ± 17.3 mg and 66.7 ± 30.1 mg, respectively. The biological value was 93 ± 9.5%, 93.6 ± 10%, and 101 ± 5%, respectively. The coefficient of total intestinal tract apparent crude protein digestibility and biological value of C. vulgaris was enhanced by ultrasonic treatment and reduced by electroporating, thus ultrasonication may be a helpful technological process in practical processing of green algae in food industry.     

Production and properties of a bioemulsifier synthesized by phenanthrene-degrading Penicillium sp.

In this study, we describe the production and properties of the bioemulsifier synthesized by Penicillium sp. grown in a medium supplemented with 300 mg L⁻¹ of phenanthrene, where bioemulsifier production was not growth-associated. The maximum emulsifier production (2 ± 0.3 g L⁻¹) and emulsifying activity in cell-free culture medium (E₂₄ = 60 ± 4%) were recorded on the 4th and 5th days, respectively. Of the various hydrocarbons tested, the best emulsifying activity was observed for kerosene, diesel, and xylene. The emulsifying agent maintained its properties over a wide range of pH (3–9), at high salinity (20% NaCl), and during exposure to elevated temperatures (93 °C). The fungal bioemulsifier was effective at these extreme environmental conditions and was able to emulsify the tested pure aromatic and aliphatic hydrocarbons and mixtures of the hydrocarbons. The bioemulsifier was composed by lipids (67%), carbohydrates (11%), and protein (7%). Myristic, stearic, and oleic were the major acids detected in the lipidic fraction.     

HPLC-DAD analysis of arbutin produced from hydroquinone in a biotransformation process in Origanum majorana L. shoot culture

The hydroquinone glucoside arbutin is a plant derived compound medically applied due to its uroantiseptic activity. It also has skin whitening properties and thus is widely used in dermatology and cosmetology. Origanum majorana L. (Lamiaceae) is known to produce arbutin, however the content of the compound in cultivated plants is very variable and low. Since plant cell and tissue cultures are capable to perform specific biotransformation reactions including glucosylation, this investigation targeted the formation of arbutin from hydroquinone in agitated O. majorana shoot cultures. For this purpose different doses of hydroquinone (96, 144, 192, 288 and 384 mg/L of medium) were added to the culture flasks in one, two or three portions. Arbutin was qualitatively and quantitatively determined in methanol extracts from dry biomass and lyophilized media using HPLC-DAD. Cells of O. majorana shoot cultures efficiently converted hydroquinone into arbutin. The product was accumulated in the biomass and was not observed (or in trace amounts) in the medium samples. Different doses as well as portioning of the precursor had a significant impact on the biotransformation process. Arbutin accumulation increased from 0.23 ± 0.03 mg/g DW up to 52.6 ± 4.8 mg/g DW in the biomass. The highest product content was observed after the addition of 192 mg/L hydroquinone in three portions. The highest efficiency of the biotransformation process, i.e. 67.5 ± 5.2% was calculated for a dose of 96 mg/L precursor divided into three portions. After further optimization of the biotransformation process, O. majorana shoot cultures could serve as a rich source of arbutin.     

Expression,purification and partial characterization of a xanthine oxidase (XOD) in Arthrobacter sp.

A xanthine oxidase (XOD) was expressed, purified and partially characterized from Arthrobacter sp. with a negative immune protocol. To determine the optimal inducer for XOD, xanthine, hypoxanthine and uric acid were added into the medium of cultivation. The results revealed that with the inducement of about 14 mM xanthine, the highest XOD activity could be detected. To separate XOD from Arthrobacter sp., the cells were first cultured without any inducement; then the total proteins of the collected cells were extracted and immunized to rabbits for the polyclonal antibodies. These antibodies were then coupled with sepharose CL 6 B, and the medium was further employed to deplete most of the cells’ back ground proteins. Began with ～20 mg crude protein from disrupted cells was subjected to the antibody medium, and ～1.45 mg protein was detected in unbinding fractions with ～92.0% of activity. The extracted xanthine oxidase was ～85% pure with native-PAGE analysis, and ～90% pure with SDS-PAGE analysis, the yield of protein was ～7.4%. The specific activity of the enzyme was 36.0 U/mg. The native enzyme should be a dimer (～280 kDa) of a protein composed with two different peptides with the mass of approximately 55.5 and 85.5 kDa, respectively. The optimal pH and temperature of this enzyme were determined at about pH 7 and 50 °C. Furthermore, EDTA revealed almost no influences on the activity.     

Serum sialic acid changes in non-insulin-dependant diabetes mellitus (NIDDM) patients following bitter melon (Momordica charantia) and rosiglitazone (Avandia) treatment

Diabetes mellitus is associated with an increase in sialic acid concentration along with other complications. Sialic acid changes in NIDDM patients were investigated following bitter melon (55 ml/24 h) and rosiglitazone (4 mg/24 h) treatment. A total of 25 patients of both sexes were used in each experimental group. Patients following bitter melon treatment showed no significant difference of serum sialic acid (57.95±4.90 vs. 57.6±5.56 mg/dl, p=0.17) and serum glucose concentration (93.7±9.63 vs. 88.35±6.31 mg/dl, p=0.78) as compared to control subjects. However, the concentration of total cholesterol was significantly high in these patients as compared to control subjects (192±14.23 vs. 170.6±15.1 mg/dl, p<0.03) but within normal range (160–200 mg/dl), suggesting the significant hypoglycemic and lipid-lowering properties of bitter melon. The patients following rosiglitazone treatment showed a significant increase of serum sialic acid concentration (60.2±5.80 vs. 57.6±5.56 mg/dl, p=0.01) along with glucose (112±6.2 vs. 88.35±6.31 mg/dl, p<0.04) and total cholesterol concentration (216.45±20.2 vs. 170.6±15.1 mg/dl, p<0.01) as compared to control subjects. In addition six of the patients had retinopathy, two of whom were suffering also from myocardial infarction and they still had a higher serum sialic acid (61.05±1.20 mg/dl), glucose (187±2.11 mg/dl), total cholesterol (239.10±5.04 mg/dl) and triglyceride (183±4.14 mg/dl) concentration, indicating a poor response of these patients to rosiglitazone. Comparison of serum sialic acid concentration of patients, following bitter melon and rosiglitazone treatment revealed no significant difference but the study showed that bitter melon could be more effective in the management of diabetes and its related complications as compared to rosiglitazone.     

Use of Saccharum spontaneum (wild sugarcane) as biomaterial for cell immobilization and modulated ethanol production by thermotolerant Saccharomyces cerevisiae VS3

Saccharum spontaneum is a wasteland weed consists of 45.10 ± 0.35% cellulose and 22.75 ± 0.28% of hemicellulose on dry solid (DS) basis. Aqueous ammonia delignified S. spontaneum yielded total reducing sugars, 53.91 ± 0.44 g/L (539.10 ± 0.55 mg/g of substrate) with a hydrolytic efficiency of 77.85 ± 0.45%. The enzymes required for hydrolysis were prepared from culture supernatants of Aspergillus oryzae MTCC 1846. A maximum of 0.85 ± 0.07 IU/mL of filter paperase (FPase), 1.25 ± 0.04 IU/mL of carboxy methyl cellulase (CMCase) and 55.56 ± 0.52 IU/mL of xylanase activity was obtained after 7 days of incubation at 28 ± 0.5 °C using delignified S. spontaneum as carbon source under submerged fermentation conditions. Enzymatic hydrolysate of S. spontaneum was then tested for ethanol production under batch and repeated batch production system using “in-situ” entrapped Saccharomyces cerevisiae VS₃ cells in S. spontaneum stalks (1 cm × 1 cm) size. Immobilization was confirmed by the scanning electron microscopy (SEM). Batch fermentation of VS₃ free cells and immobilized cells showed ethanol production, 19.45 ± 0.55 g/L (yield, 0.410 ± 0.010 g/g) and 21.66 ± 0.62 g/L (yield, 0.434 ± 0.021 g/g), respectively. Immobilized VS₃ cells showed maximum ethanol production (22.85 ± 0.44 g/L, yield, 0.45 ± 0.04 g/g) up to 8th cycle during repeated batch fermentation followed by a gradual reduction in subsequent cycles of fermentation.     

Phytochemical characterization of potential nutraceutical ingredients from Evening Primrose oil (Oenothera biennis L.)

Evening Primrose oil (EPO) is a natural product extracted by cold-pressed from Oenothera biennis L. seeds. EPO is widely used as a dietary supplement from which beneficial effects have been reported in rheumatic and arthritic conditions, atopic dermatitis, psoriasis, premenstrual and menopausal syndrome, and diabetic neuropathy. The beneficial effects of EPO are thought to be due to its γ-linolenic acid content; in contrast, little effort has been expended to characterize the non-triglyceridic constituents of EPO. In order to evaluate its potential as source of functional food ingredients our aim in this work has been identified and quantified the different components of EPO by different techniques (GC–MS and HPLC). The lipid profile showed that oleic (7%), linoleic (74%) and γ-linolenic (9%) were the most abundance fatty acids. Unsaponifiable matter and subfractions were obtained by CEE/2568/91. Separation of the compounds under study was achieved giving a reasonable analysis time and good resolution. A yield (1.82–1.95%) of unsaponifiable matter was obtained and levels of saturated hydrocarbons (0.291.97 ± 14.85 mg) were noticed. β-Sitosterol (7952.00 ± 342.25 mg/kg oil) and campesterol (883.32 ± 0.45 mg/kg oil) were predominant in phytosterol fraction (9573 mg/kg oil), while tetracosanol (236.93 ± 2.32 mg/kg oil) and hexacosanol (289.92 ± 3.41 mg/kg oil) in linear aliphatic alcohol fraction (798.04 ± 5.66 mg/kg oil). In the phenolic fraction (55.49 ± 2.76 mg/kg oil), ferulic acid (25.23 ± 2.64 mg/kg oil) was the major component. From the results obtained, it can be suggested that the Evening Primrose oil can be considered an interesting alimentary source of substances of nutraceutical value.     

Assessment of the reproductive parameters,laparoscopic oocyte recovery and the first embryos produced in vitro from endangered Canindé goats (Capra hircus)

The Canindé breed of goats (Capra hircus) is currently endangered. The aims of this study were to characterize the estrus behavior, ovulatory responses and progesterone profiles, and to evaluate the in vitro embryo production (IVP) in this breed. In Experiment 1, ten nulliparous and seven pluriparous females received medroxyprogesterone acetate (MAP)-containing sponges (60 mg) plus 75 μg d-cloprostenol for estrus synchronization and their reproductive parameters were evaluated. In Experiment 2, oocytes obtained by laparascopy from hormonally stimulated females (n = 15) were used for IVP. There was no difference (p > 0.05) between nulliparous and pluriparous goats in terms of estrus response (40.0% vs. 85.7%), time from progestagen sponge removal to the onset of estrus (62.0 ± 15.5 vs. 50.7 ± 19.2 h; mean ± SEM), duration of estrus (25.0 ± 16.1 vs. 30.0 ± 15.1 h), percentage of ovulating animals (60.0% vs. 85.7%), number of ovulations (1.2 ± 0.4 vs. 1.3 ± 0.8), and diameter of the preovulatory follicle (5.8 ± 0.5 vs. 6.1 ± 0.3 mm). Progesterone concentrations were also similar (p > 0.05) in both groups. During laparoscopic recovery, there were average 12.2 aspirated follicles and 9.1 oocytes per goat, resulting in a high recovery rate (74.3%, 182/245). A total of 78 embryos were produced (51.0%). The mean number of cells in the blastocysts at day 7 of in vitro culture was 170.3 ± 12.5. In conclusion, nulliparous and pluriparous Canindé goats exhibited similar reproductive profiles. It was possible to produce embryos in vitro, allowing the instigation of an embryo bank for preservation of this breed.     

Comparison of lipopeptide biosurfactants production by Bacillus subtilis strains in submerged and solid state fermentation systems using a cheap carbon source: Some industrial applications of biosurfactants

Biosurfactants, in general has the potential to aid in the recovery of subsurface organic contaminants (environmental remediation) or crude oils (oil recovery). However, high production and purification costs limit its use in these high-volume applications. In the present study, the efficiency of two Bacillus subtilis strains viz., DM-03 and DM-04 for the production of biosurfactants in two fermentation systems viz., solid state fermentation (SSF) and submerged fermentation (SmF) was compared. Both the B. subtilis strains produced appreciable and equal amount of crude lipopeptide biosurfactants (B. subtilis DM-03: 80.0 ± 9 mg/gds in SmF and 67.0 ± 6 mg/gds in SSF; B. subtilis DM-04: 23.0 ± 5.0 mg/gds in SmF and 20.0 ± 2.5 mg/gds in SSF) in the two different fermentation systems using potato peels as cheap carbon source. These thermostable lipopeptide biosurfactants produced by B. subtilis strains either in SSF or in SmF, exhibited strong emulsifying property and could release appreciable amount of oil from saturated sand pack column. Further, it was shown by biochemical analysis, RP-HPLC profile and IR spectra that there is no qualitative and qualitative differences in the composition of crude biosurfactants produced either in SmF or in SSF system.     

Isolation and properties of β-xylosidase from Aspergillus niger GS1 using corn pericarp upon solid state fermentation

There is growing interest in developing high-yield and low-cost production of xylanolytic enzymes for industrial applications using agroindustrial byproducts. A native strain of Aspergillus niger GS1 was used to produce β-xylosidase (EC 3.2.1.37) on solid state fermentation using corn pericarp (CP) with innovative alkaline electrolyzed water (AEW) pretreatment at room temperature. β-xylosidase was purified by ammonium sulfate fractionation followed by anion exchange and hydrophobic interaction chromatographies. β-Xylosidase showed a molecular weight of 111 kDa, isoelectric point of 5.35 and specific activity of 386.7 U (mg protein)^?1, using p-nitrophenyl-β-d-xylopyranoside as substrate, at pH 5 and 60 °C, and optimal activity at pH 4.5. Optimal temperature was 65 °C, showing full activity after 1 h at 60 °C. Activity was reduced by 1 mM β-mercaptoethanol (55.6 ± 0.1%), and enhanced by 1 mM SDS (11.0 ± 0.03%). K_m and V_max were 6.1 ± 0.9 mM and 1364 ± 105 U (mg protein)^?1, respectively, whereas k_cat was 5.1 s^?1. A predominant α-helix (41%) was determined from circular dichroism on β-xylosidase, while thermal transition profiles produced a T_m of 54.1 ± 5.8 °C, enthalpy change for unfolding of 67.4 ± 6.7 kJ/mol, and onset temperature of 37 °C. Pre-treatment of CP using AEW is an ecologically friendly alternative to chemical and heat treatments for the production of relatively high levels of β-xylosidase.     

Hypoglycemic activity of a novel anthocyanin-rich formulation from lowbush blueberry,Vaccinium angustifolium Aiton

Blueberry fruits are known as a rich source of anthocyanin components. In this study we demonstrate that anthocyanins from blueberry have the potency to alleviate symptoms of hyperglycemia in diabetic C57b1/6J mice. The anti-diabetic activity of different anthocyanin-related extracts was evaluated using the pharmaceutically acceptable self-microemulsifying drug delivery system: Labrasol. Treatment by gavage (500 mg/kg body wt) with a phenolic-rich extract and an anthocyanin-enriched fraction formulated with Labrasol lowered elevated blood glucose levels by 33 and 51%, respectively. The hypoglycemic activities of these formulae were comparable to that of the known anti-diabetic drug metformin (27% at 300 mg/kg). The extracts were not significantly hypoglycemic when administered without Labrasol, demonstrating its bio-enhancing effect, most likely due to increasing the bioavailability of the administered preparations. The phenolic-rich extract contained 287.0±9.7 mg/g anthocyanins, while the anthocyanin-enriched fraction contained 595±20.0 mg/g (cyanidin-3-glucoside equivalents), as measured by HPLC and pH differential analysis methods. The greater hypoglycemic activity of the anthocyanin-enriched fraction compared to the initial phenolic-rich extract suggested that the activity was due to the anthocyanin components. Treatment by gavage (300 mg/kg) with the pure anthocyanins, delphinidin-3-O-glucoside and malvidin-3-O-glucoside, formulated with Labrasol, showed that malvidin-3-O-glucoside was significantly hypoglycemic while delphinidin-3-O-glucoside was not.