19 research outputs found
Polyextremotolerant Amylase Produced from Novel Enterococcus with Potpourri of Applications
No full textAmylolytic toluene-tolerant Enterococcus faecalis mercadA7 isolated from asbestos contaminated black soil from the Tokat province of Turkey was used for statistically optimized liquid phase fermentation to spawn elevated levels of amylase. Box Behnken technique of Response surface Methodology is followed to optimize three significant factors influencing Amylase production. To purify the amylase, ammonium sulfate fractionation, dialysis and gel filtration on Sephadex G-100 column chromatography were used. Submerged state fermentation at statistically optimized conditions augmented amylase production levels (8467 U ml(-1)) 8.74-fold compared to the conventional optimization. Purified amylase was found to possess specific activity of 1022 U mg(-1), optimal activity at pH 9 and 60 degrees C, 80% stable at 8.0-10.0 pH range and 90% stable at 45-75 degrees C for 1 h; with Km value of 8.06 mg ml(-1) and a V-max of 4.36 mmol h(-1) ml(-1), noteworthy stability up to 43% toluene, and upto 8% NaCl. High titers of Amylase produced from Enterococcus faecalis mercadA7 might find applications in copious industrial processes due to noteworthy stability of the cell-free purified enzyme at elevated temperatures, alkaline, and high toluene or salt concentrated environments
Review on aerobic degradation of aromatic hydrocarbons: From microbial enzymes to environs
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Catalytic Profile and Amylolytic Studies of Toluene-Tolerant Enterococcus faecalis str. nov mercadA7
No full textThis work pivots around screening a toluene-tolerant bacterium with concomitant alpha-amylase production ability. Eighteen alpha-amylase-producing bacterial strains were isolated from samples collected from Tokat province of Turkey among which strain A7 showed maximum alpha-amylase production titers (968 U/ml). The strain A7 was identified as Enterococcus faecalis mercadA7 (KX298857) with 54% GC content and 98% similarity to the closest strain, Enterococcus faecalis NBRC100480 through 16srRNA typing studies. The amylase production was improved 2.6-folds compared to the basal medium at optimal conditions recorded: 37 degrees C, pH 7.0, 18 h incubation, 1% v/v inoculum content and 20% toluene (carbon) supplementation. The amylase activity was demonstrated to increase upon exposure to toluene by a yet to be determined mechanism. The various growth kinetic parameters recorded are specific growth rate, mu(max) of 0.318 h(-1); constant, K-s 10.48 mg/ml; yield coefficient, Y-x/s of 0.1157 mg/g; and cell doubling time, t(d) of 51 min. The enzyme was partially purified with a threefold increase in specific activity; it was found to be active at pH 8 and 40 degrees C; stable from 30 to 50 degrees C and 7-10 pH range; maintaining stability up to 40% of toluene. The purified enzyme's maximum velocity, V-max of 3.33 mmol/h ml with constant, Km of 5 mg/ml were determined by Line Weaver Burke plot. Both Enterococcus faecalis mercadA7 and the purified alpha-amylase might find applications in several industrial processes due to the catalytic promiscuity triggered by the presence of toluene, and augmented stability of the cell-free purified enzyme as well as the organism to high alkaline/toluene levels
Strategy for Revalorization of Cheese Whey Streams to Produce Phenyllactic Acid
No full textCheese whey (CW) is the residual liquid waste from cheese manufacturing industries, and it is rich in diverse nutrients with the potential for usage as a growth matrix for sustaining lactic acid bacteria (LAB) fermentation. Lactic acid (LA), phenyllactic acid (PLA), and their derivatives are green chemicals that can be produced by LAB metabolism with the revalorization of CW. LA and PLA are known for their antimicrobial properties, immunoregulatory functions, and production of biobased polymers (biodegradable plastics) like poly lactic acid and poly-phenyl lactic acid; hence, they find numerous applications in agricultural/food-based, pharmaceutical, biochemistry, or medical fields, as well as in antibiotic supplements in livestock feeds for animal husbandry. Herewith, we discuss our experimental strategy/concept (that can be implemented) for the microbial fermentation of cheese whey streams using robust LAB co-cultures to produce 3-PLA through sequential steps, adding a note upon their possible applications hereof. It is proposed that various food matrices, like raw cow milk, fermented cow milk, and fermented table olives, will be screened for the isolation of robust lactic acid bacteria that can be used as starter cultures for the fermentation of cheese whey liquids for producing augmented levels of LA and/or PLA. Moreover, we discuss the feasibility of practically producing PLA using an orchestrated assemblage of simple procedures, viz., isolating robust LAB strains from natural food matrices, tailoring LAB growth using a selective medium sustenance, adopting adaptive evolution procedures for improving resistance to higher temperatures and tolerance to lactic acid and/or cheese whey (low-cost substrate), and using FTIR and HPLC tools for analyzing the PLA content produced. Two Lactobacillus isolates (CM30_001 and CMW_10−3), sourced from raw cow milk and fermented cow milk whey, were found to produce 3-PLA contents of 39 mg/L and 32 mg/L in batch fermentation, using this proposed strategy
Redefining methods for augmenting lactic acid bacteria robustness and phenyllactic acid biocatalysis: Integration valorizes simplicity
No full textThe production of phenyllactic acid (PLA) has been reported by several researchers, but so far, no mention has been made of augmented PLA production using an orchestrated assembly of simple techniques integrated to improve lactic acid bacteria (LAB) metabolism for the same. This review summarizes sequentially tailoring LAB growth and metabolism for augmented PLA catalysis through several strategies like monitoring LAB sustenance by choosing appropriate starter PLA-producing LAB strains isolated from natural environments, with desirably fastidious growth rates, properties like acidification, proteolysis, bacteriophage-resistance, aromatic/texturing-features, etc.; entrapping chosen LAB strains in novel cryogels and/or co-cultivating two/more LAB strains to improve their biotransformation potential and promote growth dependency/sustainability; adopting adaptive evolution methods designed to improve LAB strains under selection pressure inducing desired phenotypes tolerant to stress factors like heat, salt, acid, and solvent; monitoring physico-chemical LAB fermentation factors like temperature, pH, dissolved oxygen content, enzymes, and cofactors for PLA biosynthesis; and modulating purification/downstream processes to extract substantial PLA yields. This review paper serves as a comprehensive preliminary guide that can evoke a strategic experimental plan to produce industrial-scale PLA yields using simple techniques orchestrated together in the pursuit of conserving time, effort, and resources
Biosynthesis and Characterization of an Anticoagulant Chitinase from Fermented Wheat Bran & Shrimp Shells’ Substratum
No full textSolid state fermentation (SSF) of wheat bran coupled with shrimp shellfish waste Citrobacter freundii str. nov. haritD11 was optimized conventionally (112.43 U/gds) and statistically (124.73 U/gds). Chitinase was purified 4.24-fold with 31% yield and specific activity of 64.87 U/mg protein. The purified chitinase had a specific activity of 64.87 U/mg with optimal activity at pH 9 and temperature 45 ºC. The enzyme was stable at 8.0–9.5 pH range with 90% stability and between 45 °C – 60 °C for 1 hour. The Km value of the Citrobacter freundii haritD11 purified chitinase with swollen chitin (substrate) is 7.53 mg/mL with a Vmax of 2.27 mmol h−1mL−1. The purified chitinase was halotolerant showing maximum activity and stability up to 9% Sodium chloride, it also possessed potential antifungal and anticoagulant activity. This is the first report to date elucidating the production of halotolerant chitinase from wheat bran supplemented with shrimp shellfish waste using Citrobacter freundii haritD11 with notable tolerance to heavy metal ions, its application as an antifungal and anticoagulant agent.HIGHLIGHTS•Optimization of solid-state fermentation of Citrobacter freundii str. nov. haritD11.•The halotolerant chitinase was produced from wheat bran supplemented with shrimp shellfish waste.•The enzyme had notable tolerance to heavy metal ions.•Chitinase was purified 4.24-fold with 31% yield and specific activity of 64.87 U/mg.•The enzyme can be applied as an antifungal and anticoagulant agent
Lactic Acid Bacteria: Isolation–characterization Approaches and Industrial Applications
No full textThe current state-of-art research pertaining to lactic acid bacteria (LAB) calls for the screening and
isolation of robust LAB strains to achieve holistic exploitation of LAB and their metabolites of
marketable importance. Hence it is imperative to comprehend LAB sources, growth requisites,
isolation and characterization strategies necessary for featured cataloging and appropriate culturing.
This review comprehensively describes various growth media and biomasses used for supporting
LAB sustenance, assay procedures needed for the isolation and characterization of LAB strains,
and their application in diverse sectors. The various industrial patents and their summarized claims
about novel LAB strains isolated and identified, methods and media (used for detection/screening,
isolation, adaptation, culturing, preservation, growth improvement), the techniques and/or
methodologies supporting LAB fermentation, and applications of produced industrial metabolites
in various market scenarios are detaile
Colors of life: a review on fungal pigments
No full textColorants find social and commercial applications in cosmetics, food, pharmaceuticals, textiles, and other industrial sectors. Among the available options, chemically synthesized colorants are popular due to their low-cost and flexible production modes, but health and environmental concerns have encouraged the valorization of biopigments that are natural and ecofriendly. Among natural biopigment producers, microorganisms are noteworthy for their all-seasonal production of stable and low-cost pigments with high-yield titers. Fungi are paramount sources of natural pigments. They occupy diverse ecological niches with adaptive metabolisms and biocatalytic pathways, making them entities with an industrial interest. Industrially important biopigments like carotenoids, melanins, riboflavins, azaphilones, and quinones produced by filamentous fungi are described within the context of this review. Most recent information about fungal pigment characteristics, biochemical production routes and pathways, potential applications, limitations, and future research perspectives are described
