COMPARATIVE STUDY OF MONASCUS SANGUINEUS AND MONASCUS PURPUREUS AS POTENTIAL SOURCES FOR RED PIGMENT PRODUCTION

Monascus spp. namely Monascus sanguineus was isolated from pomegranate (Punica granatum). In this study, the isolated M. sanguineus was compared with M. purpureus MTCC410 procured from MTCC Chandigarh, India for optimising the red pigment yield. It was observed that both strains had produced maximum red pigment on the 16 th day of incubation (21.9 CVU/ml for M. sanguineus & 16.9 CVU/ml for M. purpureus). Both strains had shown 30°C as a favourable temperature for microbial growth and pigment production. The maximum pigmentation was observed at pH 6.5 (33.9 CVU/ml) for Monascus sanguineus whereas M. purpureus produced maximum pigment at pH 5.5(16.6 CVU/ml). Oryza spp. (local unpolished rice) was found as the best solid substrate for both the strains (M. sanguineus 6.5CVU/gds and M. purpureus 12.5CVU/gds). When substrates were supplemented with glucose, a multi-fold increase in the pigment yield was observed with M. sanguineus, whereas no positive impact of glucose was observed with M. purpureus. For variable N sources, M. sanguineus showed maximum pigment with 1 % peptone whereas M. purpureus showed similar results with substrate supplemented with 5 % yeast extract and MSG. Both strains had shown anti-bacterial activity against gram positive bacteria. Presence of citrinin was confirmed in both the strains by LC-MS

Ascorbate-mediated enhancement of reactive oxygen species generation from polymorphonuclear leukocytes: modulatory effect of nitric oxide

Recent studies from our laboratory have demonstrated that ascorbate potentiated enzymatic synthesis of nitric oxide (NO) from polymorphonuclear leukocytes (PMNs). NO is known to modulate various function of PMNs such as chemotaxis, adherence, aggregation, and generation of reactive oxygen species (ROS). The role of ascorbate in the PMN phagocytosis, ROS generation, and apoptosis was thus evaluated in the present study. Ascorbate and its oxidized and cell-permeable analog, dehydroascorbate (DHA), did not affect the phagocytosis but enhanced ROS generation and apoptosis following treatment with Escherichia coli or arachidonic acid. A detailed investigation on the DHA-mediated response indicated that inhibitors of DHA uptake, reduced nicotinamide adenine dinucleotide phosphate oxidase, NO synthase, or ROS scavengers attenuated ROS generation. In DHA-treated cells, enhanced generation of peroxynitrite was also observed; thus, ascorbate-mediated ROS and reactive nitrogen species generation might mediate cytotoxicity toward the ingested microbes and subsequently, augmented PMN apoptosis. Results of the present study have helped in delineating the role of ascorbate in the modulation of NO-mediated ROS generation from PMNs

Partial Purification and Characterization of β-glucosidase fromMonascus sanguineus

The aim of the present work was to study the production and characterization of β-glucosidase from Monascus sanguineus. Agro-waste residues were screened to obtain the maximum yield of enzyme. Jack fruit seed was the best substrate for enzyme production. Studies on the optimization of pH and temperature showed acidic pH favorable for enzymatic activity, whereas the optimum temperature was 60°C. Enzyme kinetics studies with different concentration of pNPG showed the calculated value of Km approximately 0.89 mM with the non-linear regression and 0.98 mM with the linear regression techniques. The enzyme was predominantly inhibited by KCl (69.8%) and moderately inhibited by CaCl2(14.8%). Studies on the sensitivity for glucose showed that after 100 mM concentration of glucose, inhibition in pNPG hydrolysis took place. The molecular weight of the protein was estimated as 116 and 66 kDa with SDS- PAGE and zymography was carried out to verify the specific activity

Development and screening of mutants from Monascus sanguineus for secondary metabolites production

Present study was carried out to develop a potent mutant for enhancing secondary metabolite production from Monascus sanguineus. Ultraviolet (UV) treatment as physical and Ethyl methane sulphonate (EMS) as chemical mutagen was used to cultivate the mutants. All obtained mutants were screened for growth and pigment yield on three different synthetic media namely; potato dextrose agar (PDA), malt glucose peptone agar (MGPA) and Czapek Dox yeast extract Agar (CDYA). MGPA media was found suitable for pigment yield whereas appreciable growth was observed with CDYA. Highest pigment yield was obtained for mutants developed at EMS concentration of 0.6 μg/μL (EMS-3) and UV exposed for seven minutes (UV-4). Exposure to UV for 11 min suppressed the pigment production. However this exposed strain (albino) was found to be an efficient producer of lovastatin with no traces of citrinin alike parental strain. Both EMS-3 and UV-4 mutants had synthesized negligible amount of citrinin, well below regulatory toxic levels. Significant variation was also noticed on the spore morphology of tested strains. Aleuroconidia was observed with albino strain whereas clestothesium along with pigmented ascospores were noticed with UV-4 and EMS-3 mutants. In a nutshell, these strains can be endorsed as nontoxic and safe for human consumption. Keywords: Citrinin, Albino, Pigment, Mutants, Clestothesiu

Partial purification and characterization of amylase enzyme under solid state fermentation from Monascus sanguineus

Amylase is an important enzyme having a varied range of industrial applications from food to cosmetics, from pharmaceutical to detergent industry, etc. The present study was carried out considering these important applications of amylase enzyme. Monascus sanguineus also has not been explored for its efficiency to produce amylase enzymes under solid state fermentation. In the present study, various substrates were screened and among them beetroot as a solid substrate has given maximum yield (0.029 U/mL). Enzyme activity was further optimized by response surface methodology (RSM) and maximum experimental yield of 0.014 U/mL was obtained at optimized conditions of pH 5, incubation temperature of 50 °C and 10 min incubation time. A MATLAB software package was used for the graphical and regression analysis of the experimented data. Enzyme kinetics was calculated with different concentrations of starch and observed Km value was 0.055 mM from linear regression analysis. The enzyme was moderately inhibited (44.7%) by NaCl and KCl (0.105 U/mL) with minimum inhibition (14.8%) observed with SDS. Molecular weight calculation and amylase confirmation in protein sample was done by SDS–PAGE and Zymography. Calculated molecular weight was 56 kDa. Alkaline amylase produced by M. sanguineus has exhibited high efficiency towards removal of stains on cloths in combination with commercial detergent (Surf excel) at 20 °C. It can be concluded that the fungus M. sanguineus is a good source of amylase production under solid state fermentation. Application of amylase produced by M. sanguineus in detergent industry was also carried out and it was proven very effective in stain removal from the fabrics

Use of Simulated and Observed Meteorology for Air Quality Modeling and Source Ranking for an Industrial Region

The Gaussian-based dispersion model American Meteorological Society/Environmental Protection Agency Regulatory Model (AERMOD) is being used to predict concentration for air quality management in several countries. A study was conducted for an industrial area, Chembur of Mumbai city in India, to assess the agreement of observed surface meteorology and weather research and forecasting (WRF) output through AERMOD with ground-level NOx and PM10 concentrations. The model was run with both meteorology and emission inventory. When results were compared, it was observed that the air quality predictions were better with the use of WRF output data for a model run than with the observed meteorological data. This study showed that the onsite meteorological data can be generated by WRF which saves resources and time, and it could be a good option in low-middle income countries (LIMC) where meteorological stations are not available. Also, this study quantifies the source contribution in the ambient air quality for the region. NOx and PM10 emission loads were always observed to be high from the industries but NOx concentration was high from vehicular sources and PM10 concentration was high from industrial sources in ambient concentration. This methodology can help the regulatory authorities to develop control strategies for air quality management in LIMC

Microbially induced calcite precipitation using Bacillus velezensis with guar gum.

Mineral precipitation via microbial activity is a well-known process with applications in various fields. This relevance of microbially induced calcite precipitation (MICP) has pushed researchers to explore various naturally occurring MICP capable bacterial strains. The present study was performed to explore the efficiency of microbially induced calcite precipitation (MICP) via locally isolated bacterial strains and role of guar gum, which is a naturally occurring polymer, on the MICP process. The strains were isolated from local soil and screened for urease activity Further, the urease positive strain was subjected to urea and calcium chloride based medium to investigate the efficacy of isolated strain for microbial induced precipitation. Among screened isolates, the soil bacterium that showed urease positive behaviour and precipitated calcium carbonate was subjected to 16S rRNA gene sequencing. This strain was identified as Bacillus velezensis. Guar gum-a natural polymer, was used as a sole carbon source to enhance the MICP process. It was observed that the isolated strain was able to breakdown the guar gum into simple sugars resulting in two-fold increase in calcium carbonate precipitate. Major bio-chemical activities of isolated strain pertaining to MICP such as ammonium ion concentration, pH profiling, and total reducing sugar with time were explored under four different concentrations of guar gum (0.25%, 0.5%, 0.75% and 1% w/v). Maximum ammonium ion concentration (17.5 μg/ml) and increased pH was observed with 1% guar gum supplementation, which confirms augmented MICP activity of the bacterial strain. Microstructural analysis of microbial precipitation was performed using scanning electron microscopy (SEM) and X-ray diffraction (XRD) techniques, which confirmed the presence of calcium carbonate in different phases. Further, XRD and SEM based studies corroborated that guar gum supplemented media showed significant increase in stable calcite phase as compared to media without guar gum supplementation. Significant diverse group of nitrogenous compounds were observed in guar gum supplemented medium when subjected to Gas Chromatography-Mass spectrometry (GC-MS) profiling