Okoth Beryle Atieno, Makonde Huxley Mae, Bosire Carren Moraa, Kibiti Cromwell Mwiti
Department of Pure and Applied Sciences, Technical University of Mombasa, Mombasa, Kenya.
Int J Microbiol. 2025 Apr 21;2025:7818433. doi: 10.1155/ijm/7818433. eCollection 2025.
Accumulation of solid waste is a major global challenge. The conventional waste disposal methods are often ineffective in mitigating solid waste pollution, highlighting the need for other sustainable alternatives. This study is aimed at isolating and identifying potential waste-degrading microorganisms from Mwakirunge dumpsite in Mombasa, Kenya. A total of 16 soil samples were collected using a randomized block design. The samples were inoculated in enriched basal media containing mixed municipal solid waste and incubated at 37°C for 21 days. Microbial identification was conducted using standard morphological, biochemical, and molecular approaches. DNA was extracted using organic isolation methods, and PCR amplification of the 16S rRNA gene for bacteria and the ITS gene for fungi was performed. Phylogenetic analysis grouped bacterial isolates into phylum Bacillota (Firmicutes), Pseudomonadota (Proteobacteria), and Actinomycetota (Actinobacteria) that included members of the genera bacilli, , , , , , , , and . Fungal isolates belonged to the genus within the phylum Ascomycota. Three bacterial isolates B4S2 b (MZ571886), B3S1 (MZ571907), and B3S4 B (MZ571915) and one fungal isolate B2S2 a1 (MZ569413) had low sequence similarities with their closely known taxonomic relatives. The ability of the isolates to produce lipase, esterase, cellulase, amylase, and gelatinase enzymes was tested using the agar diffusion method. The results showed a significant level of enzyme production ( < 0.05). (MZ571899) exhibited the highest esterase activity; (MZ571882) exhibited the highest lipase activity, (MZ571887) exhibited the highest amylase activity, and (MZ571888) exhibited the highest cellulase activity, while (MZ571900) exhibited the highest gelatinase activity. We recommend further studies to characterize the isolates with low sequence percentage similarities to establish their true identities. In addition, further enzymatic studies are required to quantify, characterize, and purify these enzymes for industrial applications.
固体废物的积累是一项重大的全球挑战。传统的废物处理方法在减轻固体废物污染方面往往效果不佳，这凸显了对其他可持续替代方法的需求。本研究旨在从肯尼亚蒙巴萨的姆瓦基伦格垃圾场分离和鉴定潜在的废物降解微生物。采用随机区组设计共采集了16个土壤样本。将样本接种到含有混合城市固体废物的富集基础培养基中，并在37°C下培养21天。使用标准的形态学、生化和分子方法进行微生物鉴定。采用有机分离方法提取DNA，并对细菌的16S rRNA基因和真菌的ITS基因进行PCR扩增。系统发育分析将细菌分离株分为芽孢杆菌门（厚壁菌门）、假单胞菌门（变形菌门）和放线菌门（放线菌），其中包括芽孢杆菌属、 、 、 、 、 、 、 和 的成员。真菌分离株属于子囊菌门中的 属。三种细菌分离株B4S2 b（MZ571886）、B3S1（MZ571907）和B3S4 B（MZ571915）以及一种真菌分离株B2S2 a1（MZ569413）与其已知的近缘分类亲属的序列相似性较低。使用琼脂扩散法测试了分离株产生脂肪酶、酯酶、纤维素酶、淀粉酶和明胶酶的能力。结果显示酶产生水平显著（<0.05）。 （MZ571899）表现出最高的酯酶活性； （MZ571882）表现出最高的脂肪酶活性， （MZ571887）表现出最高的淀粉酶活性， （MZ571888）表现出最高的纤维素酶活性，而 （MZ571900）表现出最高的明胶酶活性。我们建议进一步研究以表征序列相似性百分比低的分离株，以确定它们的真实身份。此外，需要进一步进行酶学研究，以量化、表征和纯化这些酶用于工业应用。
