Mixed Culture Cultivation in Microbial Bioprocesses.

Mixed culture cultivation is well renowned for industrial applications due to its technological and economic benefits in bioprocess, food processing, and pharmaceutical industries. A mixed consortium encompasses to achieve growth in unsterile conditions, robustness to environmental stresses, perform difficult functions, show better substrate utilization, and increase productivity. Hence, mixed cultures are being valorized currently and has also augmented our understanding of microbial activities in communities.

Enhanced activity of hyperthermostable Pyrococcus horikoshii endoglucanase in superbase ionic liquids.

Objectives: Ionic liquids (ILs) that dissolve biomass are harmful to the enzymes that degrade lignocellulose. Enzyme hyperthermostability promotes a tolerance to ILs. Therefore, the limits of hyperthemophilic Pyrococcus horikoschii endoglucanase (PhEG) to tolerate 11 superbase ILs were explored.

Bioprocessing of Bacterial Cellulose with Graphene: Percolation Network Formation, Kinetic Analysis with Physicochemical and Structural Properties Assessment.

The understanding of microbial growth dynamics during fermentation and production of bacterial cellulose (BC) with impressive properties mimicking artificial nacre, suitable for commodity applications remains fundamentally challenging. Fabrication of BC/graphene films through a single step fermentation with improved properties provides a sustainable replacement to the conventional chemical-based modification using toxic compounds. This work reports the effect of reduced graphene oxide (RGO) on fermentation kinetics and demonstrates the formation of percolated-network in BC/RGO nanostructures.

Enhanced Biobutanol Production in Folic Acid-Induced Medium by Using NRRL B-527.

The conventional acetone-butanol-ethanol fermentation process suffers from several key hurdles viz. low solvent titer, insufficient yield and productivity, and solvent intolerance which largely affect butanol commercialization. To counteract these issues, the effect of stimulator, namely, folic acid was investigated in the present study to improve butanol titer.

Strategic intensification in butanol production by exogenous amino acid supplementation: Fermentation kinetics and thermodynamic studies.

Amino acids are vital precursors in many biochemical production pathways in addition to efficient nitrogen source which could enhance microbial growth yields. Therefore, in present study, the effect of amino acids from aliphatic and aromatic family was comprehensively evaluated in batch and integrated fed batch fermentation system. Clostridium acetobutylicum NRRL B-527 was able to utilize 54.

Stabilization of cutinase by covalent attachment on magnetic nanoparticles and improvement of its catalytic activity by ultrasonication.

This paper reports on stabilization of serine cutinase activity by immobilizing it through cross linking with glutaraldehyde on magnetic nanoparticles (Fe-NPs) and intensification of catalytic activity by ultrasonic treatment. The optimum parameters were cross linking with 10.52 mM glutaraldehyde for 90 min using 1:2 (w/w) ratio of enzyme:Fe-NPs.

Role of Trace Elements as Cofactor: An Efficient Strategy toward Enhanced Biobutanol Production.

Metabolic engineering has the potential to steadily enhance product titers by inducing changes in metabolism. Especially, availability of cofactors plays a crucial role in improving efficacy of product conversion. Hence, the effect of certain trace elements was studied individually or in combinations, to enhance butanol flux during its biological production.

Fermentative production of extracellular amylase from novel amylase producer, Tuber maculatum mycelium, and its characterization.

Truffles are symbiotic hypogeous edible fungi (form of mushroom) that form filamentous mycelia in their initial phase of the growth cycle as well as a symbiotic association with host plant roots. In the present study, Tuber maculatum mycelia were isolated and tested for extracellular amylase production at different pH on solid agar medium. Furthermore, the mycelium was subjected to submerged fermentation for amylase production under different culture conditions such as variable carbon sources and their concentrations, initial medium pH, and incubation time.

Cauliflower waste utilization for sustainable biobutanol production: revelation of drying kinetics and bioprocess development.

Efficient yet economic production of biofuel(s) using varied second-generation feedstock needs to be explored in the current scenario to cope up with global fuel demand. Hence, the present study was performed to reveal the use of cauliflower waste for acetone-butanol-ethanol (ABE) production using Clostridium acetobutylicum NRRL B 527. The proximate analysis of cauliflower waste demonstrated to comprise 17.

New Insight into Sugarcane Industry Waste Utilization (Press Mud) for Cleaner Biobutanol Production by Using C. acetobutylicum NRRL B-527.

In the present study, press mud, a sugar industry waste, was explored for biobutanol production to strengthen agricultural economy. The fermentative production of biobutanol was investigated via series of steps, viz. characterization, drying, acid hydrolysis, detoxification, and fermentation.

Sustainable biobutanol production from pineapple waste by using Clostridium acetobutylicum B 527: Drying kinetics study.

Present investigation explores the use of pineapple peel, a food industry waste, for acetone-butanol-ethanol (ABE) production using Clostridium acetobutylicum B 527. Proximate analysis of pineapple peel shows that it contains 35% cellulose, 19% hemicellulose, and 16% lignin on dry basis. Drying experiments on pineapple peel waste were carried out in the temperature range of 60-120°C and experimental drying data was modeled using moisture diffusion control model to study its effect on ABE production.

Chaotropicity: a key factor in product tolerance of biofuel-producing microorganisms.

Fermentation products can chaotropically disorder macromolecular systems and induce oxidative stress, thus inhibiting biofuel production. Recently, the chaotropic activities of ethanol, butanol and vanillin have been quantified (5.93, 37.

Interaction of carbohydrates with alcohol dehydrogenase: Effect on enzyme activity.

Alcohol dehydrogenase was covalently conjugated with three different oxidized carbohydrates i.e., glucose, starch and pectin.

Enzymatic hydrolysis of hardwood and softwood harvest residue fibers released by sulfur dioxide-ethanol-water fractionation.

The enzymatic hydrolysis of hardwood and softwood harvest residues treated by SO2-ethanol-water (SEW) fractionation was studied. The target was to convert these fibers with high yield into glucose monomers which could be further converted into biofuel by a subsequent fermentation stage. Hardwood biomass residues were efficiently digested at low enzyme dosage (5 FPU/g cellulose) whereas the softwood residues required notably higher enzyme dosage (20 FPU) for sufficient conversion.

Enhanced stability of alcohol dehydrogenase by non-covalent interaction with polysaccharides.

Non-covalent interaction of alcohol dehydrogenase with polysaccharides was studied using three neutral and three anionic polysaccharides. The process of interaction of alcohol dehydrogenase with gum Arabic was optimized with respect to the ratio of enzyme to gum Arabic, pH, and molarity of buffer. Alcohol dehydrogenase-gum Arabic complex formed under optimized conditions showed 93% retention of original activity with enhanced thermal and pH stability.

The two stage immobilized column reactor with an integrated solvent recovery module for enhanced ABE production.

The production of acetone, butanol, and ethanol (ABE) by fermentation is a process that had been used by industries for decades. Two stage immobilized column reactor system integrated with liquid-liquid extraction was used with immobilized Clostridium acetobutylicum DSM 792, to enhance the ABE productivity and yield. The sugar mixture (glucose, mannose, galactose, arabinose, and xylose) representative to the lignocellulose hydrolysates was used as a substrate for continuous ABE production.

Continuous two stage acetone-butanol-ethanol fermentation with integrated solvent removal using Clostridium acetobutylicum B 5313.

The objective of this study was to optimize continuous acetone-butanol-ethanol (ABE) fermentation using a two stage chemostat system integrated with liquid-liquid extraction of solvents produced in the first stage. This minimized end product inhibition by butanol and subsequently enhanced glucose utilization and solvent production in continuous cultures of Clostridium acetobutylicum B 5313. During continuous two-stage ABE fermentation, sugarcane bagasse was used as the cell holding material for the both stages and liquid-liquid extraction was performed using an oleyl alcohol and decanol mixture.

Improved poly-ε-lysine biosynthesis using Streptomyces noursei NRRL 5126 by controlling dissolved oxygen during fermentation.

The growth kinetics of Streptomyces noursei NRRL 5126 was investigated under different aeration and agitation combinations in a 5.0 l stirred tank fermenter. Poly-epsilon-lysine biosynthesis, cell mass formation, and glycerol utilization rates were affected markedly by both aeration and agitation.

Optimization of poly-epsilon-lysine production by Streptomyces noursei NRRL 5126.

Poly-epsilon-lysine (epsilon-PL) is a non-toxic biopolymer with antimicrobial properties. The production of epsilon-PL by Streptomyces noursei NRRL 5126 shake-flask culture was optimized by identifying the most significant medium components which affect epsilon-PL production (glycerol, proteose peptone and ammonium sulphate) by Placket-Burman design and by application of an evolutionary operation (EVOP) to determine the optimal concentrations of these components. The epsilon-PL yield increased from 41.

Glucose oxidase--an overview.

Glucose oxidase (beta-D-glucose:oxygen 1-oxidoreductase; EC 1.1.2.