International Journal of Microbiology最新文献

Over 20 million Ethiopians depend on enset (Ensete ventricosum) as a staple or costaple food. "Kocho," "Bulla," and "Amicho" are the three main food types obtained from enset. This review aimed to summarize the physicochemical and microbial dynamics of kocho. It is the most common food obtained from the scraped pseudostem and decorticated corm of enset after a long period of fermentation. The quality of kocho depends on the maturity of the enset plant, the enset processing method, the fermentation period, and the dynamics of microorganisms during the fermentation process. Microorganisms play a significant role in kocho fermentation to enhance its nutritional quality, improve sensory properties, and reduce spoilage and disease-causing agents. The populations of microbes available in kocho fermentation include lactic acid bacteria (LAB), Enterobacteriaceae, acetic acid bacteria (AAB), yeasts and molds, and Clostridium spp., which have both positive and negative impacts on kocho quality. There is a visible variation in microbial dynamics during kocho fermentation caused by the fermentation period. As the fermentation day increases, species of LAB also increase, whereas counts of Enterobacteriaceae decrease. This is due to a decrease in pH, which leads to an increase in titratable acidity. Moisture content also slightly decreases as fermentation progresses. Dynamics in the microbial population and physicochemical parameters ensure the development of desirable qualities in kocho and enhance the acceptability of the final product. Organic acids (such as lactic acid, acetic acid, and propionic acid), bacteriocins, phenolic compounds, flavonoids, and tannins are bioactive compounds produced by microorganisms during Kocho fermentation. Further research is needed on the molecular identification of microorganisms during Kocho fermentation.

Oil spills are major anthropogenic disasters that cause serious harm to marine environments. In the Philippines, traditional methods of rehabilitating oil-polluted areas were proven to be less efficient and cause further damage to the environment. Microbial degradation has poised itself to be a promising alternative to those traditional methods in remediating oil spills. Hence, the present study aimed to enrich and characterize hydrocarbon-degrading microbial consortia from oil-contaminated regions in Guimaras Island for potential use in bioremediation. A total of 75 soil samples were obtained and used as inoculum for the enrichment for hydrocarbon degraders. Afterwards, 32 consortia were recovered and subjected to the 2,6-DCPIP assay for biodegradation ability on four types of hydrocarbons: diesel, xylene, hexane, and hexadecane. The consortia that obtained the highest percent degradation for each of the four hydrocarbons were "B2" (92.34% diesel degraded), "A5" (85.55% hexadecane degraded), "B1" (74.33% hexane degraded), and "B7" (63.38% xylene degraded). Illumina MiSeq 16S rRNA gene amplicon sequencing revealed that the dominant phyla in all consortia are Pseudomonadota (previously Proteobacteria), followed by Bacillota (previously Firmicutes). Overall, the amplicon sequence variants (ASVs) retrieved were mainly from the Gammaproteobacteria class, in which many hydrocarbon-degrading bacteria are found. Predictive functional profiling of the consortium showed the presence of genes involved in the degradation of recalcitrant hydrocarbon pollutants. Fatty acid metabolism, which includes alkB (alkane-1-monooxygenase) and genes for beta oxidation, was inferred to be the most abundant amongst all hydrocarbon degradation pathways. Klebsiella sp. is the predominant ASV in all the sequenced consortia as well as the major contributor of hydrocarbon degradation genes. The findings of the study can serve as groundwork for the development of hydrocarbon-degrading bacterial consortia for the bioremediation of oil spill-affected areas in the Philippines. Likewise, this paper provides a basis for further investigation into the role of Klebsiella sp. in the bioremediation of hydrocarbon pollutants.

Breast cancer is a lethal disease in females worldwide and needs effective treatment. Targeting cancer cells with selective and safe treatment seems like the best choice, as most chemotherapeutic drugs act unselectively. Papaverine showed promising antitumor activity with a high safety profile and increased blood flow through vasodilation. At the same time, it was widely noticed that virotherapy using the Newcastle disease virus proved to be safe and selective against a broad range of cancer cells. Furthermore, combination therapy is favorable, as it attacks cancer cells with multiple mechanisms and enhances virus entrance into the tumor mass, overcoming cancer cells' resistance to therapy. Therefore, we aimed at assessing the novel combination of the AMHA1 strain of Newcastle disease virus (NDV) and nonnarcotic opium alkaloid (papaverine) against breast cancer models in vitro and in vivo. Methods. In vitro experiments used two human breast cancer cell lines and one normal cell line and were treated with NDV, papaverine, and a combination. The study included a cell viability MTT assay, morphological analysis, and apoptosis detection. Animal experiments used the AN3 mouse mammary adenocarcinoma tumor model. Evaluation of the antitumor activity included growth inhibition measurement; the immunohistochemistry assay measured caspase protein expression. Finally, a semiquantitative microarray assay was used to screen changes in apoptotic proteins. In vitro, results showed that the combination therapy induces synergistic cytotoxicity and apoptosis against cancer cells with a negligible cytotoxic effect on normal cells. In vivo, combination treatment induced a significant antitumor effect with an obvious regression in tumor size and a remarkable and significant expression of caspase-3, caspase-8, and caspase-9 compared to monotherapies. Microarray analysis shows higher apoptosis protein levels in the combination therapy group. In conclusion, this study demonstrated the role of papaverine in enhancing the antitumor activity of NDV, suggesting a promising strategy for breast cancer therapy through nonchemotherapeutic drugs.

Streptomyces are bacteria well known for producing bioactive secondary metabolites which are commonly found in diverse habitats. The biosynthesis of metabolites from Streptomyces is influenced by various factors such as the growth medium, environmental conditions, and gene regulation. This study aimed to investigate the influence of different growth media on biomass production and the antioxidant and enzyme inhibitory potential of a crude extract obtained from Streptomyces sp. G-18 isolated from high altitudinal soil of Nepal. The highest dry weight growth was observed in R2YE medium (184 mg/L), followed by R5 (144 mg/L), YEME (38 mg/L), and R5M media (30 mg/L). The crude extract showed notable antioxidant activities against free radicals. The highest alpha-amylase inhibition was observed in the R2YE medium, and worthy lipase and tyrosinase inhibition was observed in the YEME medium. However, only the R2YE medium exhibited inhibitory potential against elastase and acetylcholinesterase, while crude extracts from R5, YEME, and R5 modified did not show any such activity. Overall, our findings suggest that the production of bioactive secondary metabolites in Streptomyces sp. G-18 was significantly influenced by the growth medium. This strain may be a promising source of enzyme inhibitors with potential applications in the pharmaceutical and cosmetic industries.