Simultaneous Production of Biosurfactants and Bacteriocins by Probiotic Lactobacillus casei

Lactic acid bacteria (LAB) are ubiquitous and well-known commensal bacteria in the human and animal microflora. LAB are extensively studied and used in a variety of industrial and food fermentations. They are widely used for humans and animals as adjuvants, probiotic formulation, and dietary supplements and in other food fermentation applications. In the present investigation, LAB were isolated from raw milk samples collected from local dairy farms of Haryana, India. Further, the isolates were screened for simultaneous production of biosurfactants and bacteriocins. Biosurfactant produced was found to be a mixture of lipid and sugar similar to glycolipids. The bacteriocin obtained was found to be heat stable (5 min at 100°C). Further, DNA of the strain was extracted and amplified by the 16S rRNA sequencing using universal primers. The isolate Lactobacillus casei MRTL3 was found to be a potent biosurfactant and bacteriocin producer. It seems to have huge potential for food industry as a biopreservative and/or food ingredient

Optimization of cultural conditions for anaerobically treated distillery effluent bioremediation by an isolate Pseudomonas putida SAG45

The present study deals with the decolourisation and detoxification of distillery effluent by an isolate SAG45. Soil samples were collected from the affected disposal sites of distillery effluent treatment plant. The isolate showed the highest bioremediation of 79.5% within 4 days of cultivation in the melanoidin pigment broth. The isolate showed higher decolourisation at pH 8.0 and temperature 37 oC. However, it gives 58.9% decolourisation with 5% (v/v) distillery effluent within 8 days. Toxicity test was also carried out to assess the toxicity of distillery effluent on seed germination

Applications of submerged fermentation for biodegradation and decolourisation of melanoidins by an isolate Alcaligenes denitrificans SAG5

In laboratory conditions a bacterium was isolated, which was identified as Alcaligenes denitrificans SAG5.. The optimum decolourisation (72.6%) of melanoidin was achieved at pH 7.5 and temperature 37 °C within 4-6 days fermentation. The toxicity evaluation of distillery effluent with mung bean (Vigna radiata) revealed that the raw effluent is highly toxic as compared to treated effluent. This indicated that the effluent after bacterial treatment is ecofriendly

Enhanced decolourization of congo red dye under submerged fermentation (SMF) process by newly isolated Bacillus subtilis SPR42

Studies were carried out on the decolourization of textile azo dye using newly isolated aerobic bacterial culture. Among the 58 strains of aerobic bacteria isolated from soil contaminated with textile industry (Shivalik polymer Ltd. Faridabad) effluent, three showed remarkable ability in decolourizing the widely utilized azo dye (Congo Red). These strains also readily grew in and decolourized the high concentrations of dye (100 mgL -1). The aerobic bacterial isolate SPR42, was able to decolourize the Congo Red dye at a concentration of 100 mgL -1 upto 94% within 24 hrs at static conditions. The temperature and pH for optimum growth and activity of the isolate were reported as 37 oC and 8.5, respectively. The colorless bacterial biomass after decolourization suggested that decolourization was due to biodegradation, rather than inactive surface adsorption. Phenotypic characterization and phylogenetic analysis based on 16S rDNA sequence comparisons indicate that the strain SPR42 identified as Bacillus subtilis. This isolate can be a potential strain for biological treatment of effluents of TPI (Textile Processing Industry)

Production and Structural Characterization of Lactobacillus helveticus

A probiotic strain of lactobacilli was isolated from traditional soft Churpi cheese of Yak milk and found positive for biosurfactant production. Lactobacilli reduced the surface tension of phosphate buffer saline (PBS) from 72.0 to 39.5 mNm−1 pH 7.2 and its critical micelle concentration (CMC) was found to be 2.5 mg mL−1. Low cost production of Lactobacilli derived biosurfactant was carried out at lab scale fermenter which yields 0.8 mg mL−1 biosurfactant. The biosurfactant was found least phytotoxic and cytotoxic as compared to the rhamnolipid and sodium dodecyl sulphate (SDS) at different concentration. Structural attributes of biosurfactant were determined by FTIR, NMR (1H and 13C), UPLC-MS, and fatty acid analysis by GCMS which confirmed the presence of glycolipid type of biosurfactant closely similar to xylolipids. Biosurfactant is mainly constituted by lipid and sugar fractions. The present study outcomes provide valuable information on structural characterization of the biosurfactant produced by L. helveticus MRTL91. These findings are encouraging for the application of Lactobacilli derived biosurfactant as nontoxic surface active agents in the emerging field of biomedical applications

Functional characterization of biomedical potential of biosurfactant produced by Lactobacillus helveticus

Various lactic acid bacteria (LAB) have been isolated and screened for biosurfactant production and their biomedical and food applications. Additionally, various different concentrations of the biosurfactant (0.625–25 mg ml−1) were used to evaluate its antimicrobial and antiadhesive potential against a range of pathogenic microorganisms. Biosurfactant was found to be stable to pH changes over a range of 4.0-12.0, being most effective at pH 7 and showed no apparent loss of surface tension and emulsification efficiency after heat treatment at 125 °C for 15 min. Present study demonstrated that biosurfactant obtained from Lactobacillus helveticus has the ability to counteract effectively the initial deposition of biofilm forming pathogens to silicone surfaces and to significantly sluggish biofilm growth

Novel Castellaniella denitrificans SA13P as a Potent Malachite Green Decolorizing Strain

Triphenylmethane dyes represent a major group of dyes causing serious environmental hazards. Malachite Green is one of the commonly and extensively used triphenylmethane dyes although it is carcinogenic and mutagenic in nature. Various physicochemical methods have been employed for its elimination but are highly expensive, coupled with the formation of huge amount of sludge. Hence, biological methods being ecofriendly are good alternatives. In the present study, the novel bacterial isolate SA13P was isolated from UASB tank of tannery effluent treatment plant. Phylogenetic characterization of 1470 bp fragment of SA13P has revealed its similarity with Castellaniella denitrificans. This strain has been found to decolorize the dye (malachite green) at a concentration of 100 mg L−1 (80.29%). Decolorization was done by living bacterial cells rather than adsorption. Growth conditions have also been optimized for the decolorization. Maximum decolorization was observed at a temperature of 37°C and pH 8.0. Also, it has been found that bacterization of seeds of Vigna radiata with Castellaniella denitrificans SA13P increases germination rate. We have reported for the first time that Castellaniella denitrificans SA13P may be used as a novel strain for dye decolorization (malachite green) and biological treatment of tannery effluent

Probiotic Properties of Lactobacillus plantarum

Recently, probiotic lactic acid bacteria have been utilized as therapeutic supplements and food additives. Nowadays, the interest has been increased regarding the commercial utilization of probiotic LAB strains isolated from traditional fermented food products. Therefore, the present study was aimed to investigate the probiotic properties of lactic acid bacteria isolated from traditional food sources viz. dosa batter and sauerkraut. Total 7 lactic acid bacteria were obtained, 4 from dosa batter and 3 from sauerkraut, out of which one isolate from each food source were selected based on their broadest antagonistic spectrum. These strains were identified using 16S r RNA technique as Lactobacillus plantarum DB-2 (isolated from dosa batter) and Lactobacillus plantarum SK-3 (isolated from sauerkraut). The investigation of acid-bile tolerance, antibiotic sensitivity, auto-aggregation, co-aggregation, bacterial adhesion to hydrocarbons were confirmed. The results revealed normal growth of L. plantarum DB-2 and L. plantarum SK-3 in the presence of low pH, high bile salt concentration and ability to produce antimicrobial compounds viz. bacteriocin and H2 O2 . No gelatinase, lipase and hemolytic activity were observed. Natural susceptibility to the tested antibiotics was investigated. Thus, according to these results, L. plantarum DB-2 and SK-3 proved the good probiotic candidates as they survived during stress conditions posing to them and can be exploited for the preparation of nutraceutical products. This study also revealed the potential of using LAB and /or bacteriocin produced by them as food bio preservative to control food borne pathogenic bacteria in near future

International Journal of Microbial Resource Technology Potential plant growth promoting activity of Bacillus licheniformis UHI(II)7

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A GC-MS Based Metabolic Profiling of Probiotic Lactic Acid Bacteria Isolated from Traditional Food Products

A GC-MS based metabolic profiling was carried out to study metabolic differences of lactic acid bacteria isolated from different food sources. Metabolic fingerprinting is a non-targeted procedure where all detectable peaks are considered to establish sample classification. A total of 40 compounds were identified as major metabolites contributing to the difference among five different probiotic lactic acid bacteria. Some of the metabolites identified in this study have been reported as a defrosting agent, antioxidant, flavour agent, antimicrobial, natural food additive, anti-inflammatory, anti-sleep disorder agent and anti-cancer agents. These results suggest that GC-MS based metabolomic analysis is a useful tool to facilitate future investigations into the characterization of probiotic lactic acid bacteria