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The objective of the current research was to identify and evaluate the possibility of production of pectinase, also known as pectin degrading enzymes, from indigenous bacterial strains. Qualitative screening of isolated bacterial strains showed that among 29 bacterial strains, 5 have maximum enzymatic activity. The highest pectinase producing strains were quantitatively analyzed for enzyme production. SH7 strain was found as highest pectinase producer (0.77 IU/mL) that was further analyzed to molecular level by amplification of 16s rRNA. It was found 100% similar with other reported strains of Bacillus thuringiensis. Medium optimization was performed to optimize fermentation conditions for maximum enzyme yield. An experimental design containing 12 experimental runs was designed by Plackett–Burman design (PBD). Maximum pectinase activity was obtained at 45°C after 24 h when the growth medium was supplemented with 2.5% nitrogen, 5.0% substrate, MgSO4 as metal ion, 1% inoculum size, and pH was adjusted to 6. Factorial regression analysis of the PBD design was performed and the overall design was also found significant in terms of R square value. In PBD, the most significant factors for production were temperature, pH, metal ion concentration, and nitrogen source. Central composite design (CCD) design consisting of 26 experimental runs was employed to optimize these four significant factors. The overall model summary showed maximum pectinase activity (19.2 IU/mL) at 37°C temperature, 0.08 NaCl, 1.7% nitrogen source, and pH 8.4. In CCD, NaCl, nitrogen source, and pH were also reported as significant factors by the Pareto chart, probability plots, and 3D interactions.

This article presents the results of an ongoing inventory of Ascomycota in Yunnan, China, carried out as part of the research project series "Exploring ascomycete diversity in Yunnan". From over 100 samples collected from diverse host substrates, microfungi have been isolated, identified and are currently being documented. The primary objective of this research is to promote the discovery of novel taxa and explore the ascomycete diversity in the region, utilising a morphology-phylogeny approach. This article represents the second series of species descriptions for the project and introduces three undocumented species found in the families Bambusicolaceae, Dictyosporiaceae and Periconiaceae, belonging to the suborder Massarineae (Pleosporales, Dothideomycetes). These novel taxa exhibit typical morphological characteristics of Bambusicola, Periconia and Trichobotrys, leading to their designation as Bambusicola hongheensis, Periconia kunmingensis and Trichobotrys sinensis. Comprehensive multigene phylogenetic analyses were conducted to validate the novelty of these species. The results revealed well-defined clades that are clearly distinct from other related species, providing robust support for their placement within their respective families. Notably, this study unveils the phylogenetic affinity of Trichobotrys within Dictyosporiaceae for the first time. Additionally, the synanamorphism for the genus Trichobotrys is also reported for the first time. Detailed descriptions, illustrations and updated phylogenies of the novel species are provided, and thus presenting a valuable resource for researchers and mycologists interested in the diversity of ascomycetes in Yunnan. By enhancing our understanding of the Ascomycota diversity in this region, this research contributes to the broader field of fungal taxonomy and their phylogenetic understanding. [ABSTRACT FROM AUTHOR]

Pharmaceutical effluents primarily enter aquatic environments through the discharge of treated and untreated wastewater from various sources, including hospitals, pharmaceutical manufacturing facilities, and households. Microbes sourced from pharmaceutical effluents such as Pseudomonas spp. pose a significant public health concern because of their high levels of resistance to multiple drugs and extreme multidrug resistance. Therefore, the present study was conducted for the isolation, identification, and molecular characterization of selected isolates from pharmaceutical effluents and also determined their antibiotic sensitivity patterns. From June 2016 to March 2017, a study was conducted on four well-known pharmaceutical companies specializing in antibiotic production in Dhaka and Gazipur. Four wastewater samples were collected from various origins and then brought to the Bacteriology laboratory for microbiological examination. Twelve pure isolates were obtained and characterized through cultural and biochemical tests while molecular identification of Pseudomonas spp. was performed using the 16S rRNA gene sequence. Twelve commercially available antibiotics were used for antibiotic sensitivity tests using Kirby-Bauer disk diffusion methods. We isolated the most predominant isolates, Pseudomonas aeruginosa (41.67%), followed by Bacillus spp. (33.33%) and Staphylococcus spp. (25%) respectively. Among 12 antibiotics, ciprofloxacin is 100% sensitive against P. aeruginosa, while the remaining 11 antibiotics are 100% resistant. Bacillus spp. showed 100% resistance to all antibiotics while 50% sensitive to vancomycin and 100% to chloramphenicol, respectively. Staphylococcus spp. was 100% resistant to all antibiotics. Our research suggested that P. aeruginosa is the reservoir of antibiotic resistance genes and spreads disease to humans from the environment. The findings of this study, i.e., the isolation, identification, and characterization of antibiotic-resistant bacteria from pharmaceutical effluent have highlighted, comprehended, and mitigated the dissemination of antibiotic resistance and opportunistic bacteria. [ABSTRACT FROM AUTHOR]