Techniques for immobilizing enzymes to create durable and effective biocatalysts

Leveraging Lactobacillus plantarum probiotics to mitigate diarrhea and Salmonella infections in broiler chickens

Anaerobic bacteria, such as Lactobacillus plantarum (LP), are known to play a significant role in maintaining gut health and protecting against enteric pathogens in animals. The present study aimed to develop a safe, affordable, and eco-friendly method for producing LP-based probiotics and evaluate their efficacy in mitigating Salmonella-induced diarrhea in broiler chickens. The study employed three different culture media (MRS, TSB, and Baird Parker) to grow LP, which was then dried using a spray-drying technique to produce a stable probiotic formulation. When administered to broiler chickens, the LP probiotic derived from the MRS medium significantly improved body weight gain (4.147-fold increase over 4 weeks) compared to the other two culture conditions. Importantly, the LP probiotic treatment could substantially reduce the diarrhea index in broilers, with up to an 86.45% improvement in Salmonella-induced enteric infections. The beneficial effects were attributed to the ability of LP to modulate the gut microbiome, enhance the integrity of the intestinal mucosa, and mitigate the pathogenic effects of Salmonella. These findings demonstrate the potential of anaerobic Lactobacillus plantarum as a safe and effective probiotic intervention for controlling enteric diseases and improving production outcomes in poultry farming. The developed method provides a sustainable approach to harness the beneficial properties of this anaerobic bacterium for animal health and welfare.

Enhancing the Stability and Anticancer Activity of Escherichia coli Asparaginase Through Nanoparticle Immobilization: A Biotechnological Perspective on Nano Chitosan

There is a shortage in the experimental research directly comparing the effectiveness of different nanoparticles in boosting asparaginase (ASNase) activity. This study assessed the impact of various nanoparticles on enhancing ASNase activity, stability, and anticancer effects through immobilization. Escherichia coli ASNase was immobilized on different nanoparticles, and its efficiency was measured. The research included analyzing the enzyme's secondary structure, stability, activity at different temperatures, kinetic parameters, shelf life, and activity in blood serum. The anticancer efficacy was determined by measuring the IC50. The study also investigated the anticancer mechanisms by examining the enzyme's toxicity on cancer cells, focusing on apoptosis indicators like nuclear intensity, membrane permeability, mitochondrial membrane permeability, and cytochrome c release. Among the tested nanoparticles, nano chitosan yielded the best improvements. ASNase immobilized on nano chitosan reached 90% immobilization efficiency fastest among the studied nanoparticles, achieving this within 72 h, whereas other nanoparticles took 120 h. Immobilization modified ASNase's secondary structure by increasing alpha helices and reducing random coils, with nanochitosan and magnetic iron oxide showing the most pronounced effects. Immobilized ASNase exhibited enhanced activity, stability across temperature (widest with nanochitosan, 25-65 °C), and a broader optimal pH range compared to the free enzyme, with a Km of 1.227 mM and a Vmax of 454.54 U/mg protein. Notably, the nano-chitosan-immobilized ASNase retained over 85% of its activity after 9 months of storage and maintained high activity in blood serum. This improved stability and activity translated into the highest anticancer activity (Lowest IC50) and was more effective than doxorubicin in disrupting cancer cell structures.

Enhanced Immobilization of Enzymes on Plasma Micro-Nanotextured Surfaces and Microfluidics: Application to HRP

The enhanced and direct immobilization of the enzyme horseradish peroxidase on poly(methyl methacrylate) (PMMA) microchannel surfaces to create a miniaturized enzymatic reactor for the biocatalytic oxidation of phenols is demonstrated. Enzyme immobilization occurs by physical adsorption after oxygen plasma treatment, which micro-nanotextures the PMMA surfaces. A five-fold enhancement in immobilized enzyme activity was observed, attributed to the increased surface area and, therefore, to a higher quantity of immobilized enzymes compared to an untreated PMMA surface. The enzymatic reaction yield reached 75% using a flow rate of 2.0 μL/min for the reaction mixture. Additionally, the developed microreactor was reused more than 16 times without affecting the enzymatic conversion yield. These results demonstrate the potential of microchannels with plasma micro/nanotextured surfaces for the rapid and facile fabrication of microfluidic enzymatic microreactors with enhanced catalytic activity and stability.

The distribution of rennet activity between the cheese aging process and whey is not influenced by the association of enzymes with caseins

The division of rennet in cheesemaking is split between the curd and whey, influencing the taste and texture of aged cheeses. Our study aimed to examine how raising the protein concentration in reconstituted skim milk (up to 8.8 %) affects the distribution of calf rennet activity (RA) in rennet curds produced through two methods: renting only and renneting with glucono-δ-lactone (GDL) to achieve slow acidification. The distribution of rennet activity (RA) into curds increased as the concentration of skim milk rose, ranging from 8.6 % to 29.1 % without acidification, and from 6.5 % to 19.4 % when combined with slow acidification. This increase seemed to be related to the retention of moisture and protein. Surprisingly, the concentration of residual RA in the whey (measured in international milk clotting units, IMCU/mL) remained unaffected and remained consistent with the initial IMCU/mL of milk. This suggests that the division of RA between curd and whey is not influenced by the association of enzymes with caseins (CNs). Instead, it is possible that the strength of interactions between CNs themselves plays a significant role. These findings could be valuable for research focused on enhancing the cheese aging process.