A Response Surface Methodological Approach for Large-Scale Production of Antibacterials from Lactiplantibacillus plantarum with Potential Utility against Foodborne and Orthopedic Infections.

A variety of bacteria, including beneficial probiotic lactobacilli, produce antibacterials to kill competing bacteria. Lactobacilli secrete antimicrobial peptides (AMPs) called bacteriocins and organic acids. In the food industry, bacteriocins, but even whole cell-free supernatants, are becoming more and more important as bio-preservatives, while, in orthopedics, bacteriocins are introducing new perspectives in biomaterials technologies for anti-infective surfaces. Studies are focusing on Lactiplantibacillus plantarum (previously known as Lactobacillus plantarum). L. plantarum exhibits great phenotypic versatility, which enhances the chances for its industrial exploitation. Importantly, more than other lactobacilli, it relies on AMPs for its antibacterial activity. In this study, Response Surface Methodology (RSM) through a Box-Behnken experimental design was used to estimate the optimal conditions for the production of antibacterials by L. plantarum. A temperature of 35 °C, pH 6.5, and an incubation time of 48 h provided the highest concentration of antibacterials. The initial pH was the main factor influencing the production of antibacterials, at 95% confidence level. Thanks to RSM, the titer of antibacterials increased more than 10-fold, this result being markedly higher than those obtained in the very few studies that have so far used similar statistical methodologies. The Box-Behnken design turned out to be a valid model to satisfactorily plan a large-scale production of antibacterials from L. plantarum.

Particulate pollution and its toxicity to fish: An overview.

Aquatic ecosystems cover more than two-thirds of the Earth's surface and play a vital role in maintaining a stable global temperature and providing various benefits to an expanding human population. However, human activities are causing negative effects on these ecosystems. Particulate matter (PM) refers to tiny particles with a variable composition and a diameter of <100 µm. These particles can settle in water and be consumed by fish, posing a health hazard to them. Additionally, these particles can scatter light, which can negatively impact the growth of plants and algae in the water, and ultimately affect the aquatic food chain. Particle pollution can transport contaminants, such as toxic heavy metals and organic compounds, which can accumulate in fish tissues and be ingested by humans. These pollutants can harm aquatic life through various processes, such as physical damage, ingestion, bioaccumulation, light attenuation, and toxicity. This review article specifically focuses on different sources of particulate matter that impact fish and the mechanisms by which these pollutants can cause toxicity in fish.