Lactobacillus plantarum and Lactobacillus helveticus fermented tender coconut water probiotic beverage: A comparison study

Introduction and Aim: Coconut water is reflected as an elixir to the body. It has become a popular beverage among different age groups because of its deliciousness and high nutritional value. The growth, fermentation efficiency, and bioactive content generation by the probiotic bacteria Lactobacillus plantarum and Lactobacillus helveticus in coconut water were evaluated in this study to develop a new non-dairy probiotic beverage. The classification of species was based on its biochemical features, morphology, physiology, as well as its probiotic properties.   Materials and Methods: Batch fermentations were conducted for the aseptically collected coconut water for two days at a constant temperature of 37°C with Lactobacillus plantarum and Lactobacillus helveticus. The fermented samples were microbiologically and chemically analysed for checking the presence of bioactive components and the physicochemical properties.   Results: After a 48-hour fermentation with Lactobacillus plantarum and Lactobacillus helveticus, tender coconut water showed a significant increase in the bio-actives including cyanocobalamin and riboflavin content. The antibacterial activity shown by the final fermented product indicated its potential for acting against foodborne pathogens.   Conclusion: The findings revealed that following fermentation with Lactobacillus helveticus and Lactobacillus plantarum, the species were able to improve the nutritional content of tender coconut water. Between these two Lactobacillus strains, L. plantarum fermented tender coconut water exhibited higher nutritional values compared to the latter.

Detoxification and color removal of Congo red by a novel Dietzia sp. (DTS26) - a microcosm approach

The present study deals with the decolorization and detoxification of Congo red (CR) by a novel marine bacterium Dietzia sp. (DTS26) isolated from Divar Island, Goa, India. The maximum decolorization of 94.5% (100 mg L(-1)) was observed under static condition within 30 h at pH 8 and temperature 32±2°C. Bacterially treated samples could enhance the light intensity by 38% and the primary production levels 5 times higher than the untreated. The strain was also able to reduce COD by 86.4% within 30 h at 100 mg L(-1) of CR dye. The degraded metabolites of CR dye were analyzed by FTIR, HPLC, GC-MS and the end product closely matches with 4-amino-3-naphthol-1-sulfonate which is comparatively less toxic than CR. Bioassay experiments conducted in treated samples for Artemia franciscana showed better survival rates (after 72 h) at higher concentration of CR (500 mg L(-1)). This work suggests the potential application of DTS26 in bioremediation of dye wastes and its safe disposal into coastal environment.

A comparative rapid and sensitive method to screen l-asparaginase producing fungi

Fungi are well known to produce various industrial enzymes and secondary metabolites with different colours. Fungi producing l-asparaginase enzyme are conventionally screened on medium containing phenol red (PR). The contrast between enzyme-hydrolysed zone and unhydrolysed l-asparagine is not very evident and distinct in medium containing PR and bromothymol blue (BB) due to coloured secondary metabolite production. Thus, PR and BB limit and affect the detection and screening method. In the present investigation, an improved method for screening is reported by comparing with PR and BB, wherein methyl red (MR) is incorporated as pH indicator. The enzyme activity was distinctly observed (red and light-yellow) in MR incorporated medium compared to PR and BB.

Optimization of Monacolin K Production by Monascus purpureus MTTC 410 in Submerged Fermentation

Monascus purpureus, a traditional Chinese fermentation fungus, is used as a natural dietary supplement. Among the metabolites of M. purpureus, monacolin K (lovastatin) is found to be very important and have been proven to be cholesterol-lowering drug. They are potent inhibitor of 3-hydroxy-3-methylglutaryl-CoA reductase (HMG-CoA). Cultural condition has a significant influence on the yield of monacolin K. This study deals with the cultural parameters like carbon, nitrogen, pH and temperature on monacolin K production by M. purpureus. The effect of different carbon sources (glucose, fructose, maltose, sucrose and lactose) on monacolin K production indicated that maltose as carbon source yielded more monacolin K (71.07 mg/L) followed by glucose (61.99 mg/L). Among different nitrogen sources (ammonium nitrate, ammonium sulphate, yeast extract, peptone and ammonium chloride), peptone produces highest concentration of monacolin K (62.00 mg/L) followed by ammonium chloride (52.30 mg/L). Optimum temperature was found to be 28°C with 72 mg/L of monacolin K. pH also plays a major role on the synthesis of monacolin K. pH 5.0 was found optimum (56 mg/L) when compared to other pH values. An enhanced amount of monacolin K (81.27 mg/L) was achieved with the above optimum parameters by controlling the fermentation condition.

Isolation and characterization of dihydromonacolin-MV from Monascus purpureus for antioxidant properties

The methanolic extract of Monascus purpureus cultivated by solid-state fermentation on rice showed strong 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity and better yield as compared to other polarity based extracted fractions. It was selected for further purification of the antioxidant. The activity-guided repeated fractionation of methanolic extract on a silica gel column chromatography yielded a compound that exhibited strong antioxidant activity. Based on the spectroscopic analysis by UV, IR, 1H NMR, 13C NMR, 2D-HSQCT NMR, and MS, the antioxidant isolated was elucidated as a derivative of dihydromonacolin-K, where the ester group is 2-methyl propionate, designated as dihydromonacolin-MV. The DPPH radical was significantly scavenged by the dihydromonacolin-MV (IC50 20+/-1 microg ml-1). The dihydromonacolin-MV showed strong inhibition of lipid peroxidation in a liposome model with an IC50 value of 5.71+/-0.38 microg ml-1 and superoxide radical scavenging activity with an IC50 value of 163.97+/-2.68 microg ml-1.