Bacitracin is one of the most important antibiotics used in different biomedical fields. It helps to achieve sizeable amount of foreign exchange due to its use in the poultry feed. The cheap agricultural wastes are readily available for the preparation of fermentation media used for bacitracin production. The microorganisms could be mutated with different chemicals and UV radiation to improve bacitracin production. Thus, the current study was focused on the synthesis of low‐cost and effective bacitracin by mutant strains of Bacillus licheniformis, employing the submerged fermentation technique. The bacteria were exposed to the UV irradiation for various time periods ranging from 5 to 40 min. These mutants were named as BLAA‐5–BLAA‐40. Mutant strain BLAA‐25 produced maximum bacitracin, with significantly high activity (142.81 IU/mg) against Klebsiella pneumoniae but less activity against Escherichia coli (115.19 IU/mg). Several fermentation conditions were investigated to optimize bacitracin production. The highest bacitracin yield was obtained by an inoculum size of 10%, fermentation period 48 hr, pH 7, T = 37°C, using soybean meal as a substrate. Among all substrates, cucumber peel was the substrate showing the highest minimum inhibitory concentration (2.3 mg/ml and 2.7 mg/ml against K. pneumoniae and E. coli respectively). A comparison between commercial and experimentally produced Zn bacitracin showed that commercial bacitracin has a low activity (63.2 IU/mg) as compared with experimental bacitracin. Hence, the agro wastes and mutation could be used to increase the synthesis of Zn bacitracin in B. licheniformis.

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深层发酵技术增强微生物生产杆菌肽锌的优化

杆菌肽是用于不同生物医学领域的最重要的抗生素之一。由于用于家禽饲料，它有助于实现大量外汇。廉价的农业废物很容易用于制备用于杆菌肽生产的发酵培养基。微生物可以用不同的化学物质和紫外线辐射进行突变，以提高杆菌肽的产量。因此，目前的研究集中在利用深层发酵技术通过地衣芽孢杆菌突变菌株合成低成本和有效的杆菌肽。细菌暴露在紫外线照射下的时间范围从 5 到 40 分钟不等。这些突变体被命名为 BLAA-5-BLAA-40。突变株 BLAA-25 产生了最大的杆菌肽，具有显着的高活性（142. 81 IU/mg）对抗肺炎克雷伯菌，但对大肠杆菌的活性较低（115.19 IU/mg）。研究了几种发酵条件以优化杆菌肽生产。最高杆菌肽产量是通过 10% 的接种量、发酵时间 48 小时、pH 7、T = 37°C、使用豆粕作为底物获得的。在所有底物中，黄瓜皮是显示出最高最低抑菌浓度的底物（对肺炎克雷伯菌和大肠杆菌分别为 2.3 毫克/毫升和 2.7 毫克/毫升）。商业和实验生产的锌杆菌肽之间的比较表明，与实验杆菌肽相比，商业杆菌肽的活性较低（63.2 IU/mg）。因此，农业废弃物和突变可用于增加地衣芽孢杆菌中锌杆菌肽的合成。