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Di-n-butyl phthalate (DBP) is a prevalent phthalate ester widely used as a plasticizer, leading to its widespread presence in various environmental matrices. This study presents an innovative microbial immobilization strategy utilizing biochar, calcium alginate (alginate-Ca, (C12H14CaO12)n), and waterborne polyurethane (WPU) composites to enhance the biodegradation efficiency of DBP. The results revealed that rice husk biochar, pyrolyzed at 300 °C, exhibits relatively safer and more stable physical and chemical properties, making it an effective immobilization matrix. Additionally, the optimal cultural conditions for Bacillus aquimaris in DBP biodegradation were identified as incubation at 30 °C and pH 7, with the supplementation of 0.15 g of yeast extract, 0.0625 g of glucose, and 1 CMC of Triton X-100. Algal biotoxicity results indicated a significant decrease in biotoxicity, as evidenced by an increase in chlorophyll a content in Chlorella vulgaris following DBP removal from the culture medium. Finally, microbial community analysis demonstrated that encapsulating B. aquimaris within alginate-Ca and WPU layers not only enhanced DBP degradation, but also prevented ecological competition from indigenous microorganisms. This novel approach showcases the potential of agricultural waste utilization and microbial immobilization techniques for the remediation of DBP-contaminated environments. [ABSTRACT FROM AUTHOR]

Modern biotechnology takes into account cost, performance, and respect for the environment to set up an industrial process. In this sense, the study's goal is to highlight the presence of indigenous microbial microflora in the Terga thermal power plant effluents, which are capable of secreting extracellular hydrolases. Four different extracellular hydrolases classes, which are most of the time used in bioindustry, namely protease, amylase, lipase, and cellulase, were investigated in agar plate assay, to select microorganisms with an interesting enzymatic potential adapted to this type of environment. Consequently, the results have shown that among twelve isolated bacterial strains, three strains were screened based on their enzymatic potential, and were later identified by 16S rRNA gene sequencing, i.e. showing that the strains belong to the genus Pseudomonas aeruginosa, and Bacillus wiedmannii with a similarity percentage of 99.33% and 100%, respectively, with their corresponding type of strains. Among them, the strain LGMT10 that belongs to the Bacillus genus, and is closely related to Bacillus aquimaris, showed a 16S rRNA sequence similarity with the type of strain of 99.23%. This strain presents adequate characteristics to resist the harsh conditions of pH and NaCl. It could grow against wide ranges of NaCl concentrations between 0-12% (w/v), pH 5.5-12, and was able to produce extracellular hydrolases (i.e., protease, amylase, and cellulase) against pH ranges of 6.8-12 and NaCl concentrations between 0-12% (w/v) at 30 °C. This strain's intriguing enzymatic potential, as well as its pH and salinity tolerance, make it a promising candidate for various biotechnological applications in detergent, leather, textile, and food processing industries. [ABSTRACT FROM AUTHOR]

A 49‐day rearing trial was conducted to investigate the effects of Bacillus aquimaris T16 on growth, survival, and digestive and immune‐related enzyme activities in larval and juvenile Yesso scallop, Patinopecten yessoensis. Veliger larvae (Day 2 postfertilization [d2 PF]) were split into three treatments: control (provided with a diet only of microalgae), low T16 supplementation (1 × 104 cells/mL at final concentration), and high T16 supplementation (1 × 106 cells/mL at final concentration). Results showed that specific growth rates; survivals; and pepsin, amylase, and/or cellulase activities of umbo larvae (d13 PF), crawling–pediveliger larvae (d28 PF), and juveniles (d51 PF) in the low and/or high T16 supplementation treatments were significantly higher than those in the control group. Larvae and juveniles fed diets containing low and/or high T16 supplementations had significantly increased lysozyme, superoxide dismutase, and catalase activities compared with those fed the diet of microalgae. In addition, T16 protected juveniles against challenge by Vibrio splendidus. These data suggest that the addition of T16 can improve growth, enhance digestive enzyme activity, and stimulate the innate immune system of scallop larvae and juveniles and enhance the resistance of juveniles against V. splendidus. [ABSTRACT FROM AUTHOR]

Aim: Di-(2-ethylhexyl) phthalate (DEHP) has been identified as an endocrine-disrupting chemical, commonly found in the environment. The aim of this study was to isolate bacteria from municipal solid waste (MSW) leachates in Nigeria and its ability to degrade DEHP. Methodology and results: The DEHP degrading bacterium was isolated and identified. The degradation process was monitored aerobically at varying temperature and pH and the metabolites were determined using High Performance- Liquid Chromatography and Gas Chromatography-Mass Spectrometry, respectively. Based on the morphology and the 16S rDNA sequence, the bacterial isolate was identified as Bacillus aquimaris. B aquimaris was able to degrade 99% of 200 mg/L DEHP within 12 days. The optimum pH and temperature for its biodegradation were 8 and 25 °C, respectively and the intermediate metabolites were identified as butyl octyl phthalate and phthalic acid. Conclusion, significance and impact of study: This study showed that B. aquimaris could be a useful tool for the biodegradation of DEHP in the environment. [ABSTRACT FROM AUTHOR]

Our objective was to evaluate the role of plant growth-promoting bacteria to protect maize ( Zea mays L.) plants against salt damage. Bacillus aquimaris DY-3 based on their 16S rDNA sequences, the most tolerant to salinity and the synthesis of indole acetic acid was selected for further studies. Strain was inoculated on maize roots growing in sterilized sand under salt stress conditions (1% NaCl). After one week, plant growth was promoted by bacterial inoculation regardless of salt stress and non-salt stress. Chlorophyll content, leaf relative water content, accumulation of proline, soluble sugar and total phenolic compound, and activities of superoxide dismutase, catalase, peroxidase and ascorbate peroxidase were enhanced, while lipid peroxidation levels and Na content were decreased. The results showed that B. aquimaris DY-3 alleviated the salt stress in maize, likely through the integration of the antioxidant enzymes and the non-antioxidant systems that improve the plant response. Hence, the application of indole acetic acid synthesizing plant growth-promoting bacteria may represent an important alternative approach to decrease the impact of salt stress on crops. [ABSTRACT FROM AUTHOR]