Department of Botany and Microbiology, Faculty of Science, Zagazig University, Zagazig, 44519, Egypt.
BMC Microbiol. 2023 Oct 17;23(1):295. doi: 10.1186/s12866-023-03035-0.
Hyaluronic acid (HA) has gained significant attention due to its unique physical, chemical, and biological properties, making it widely used in various industries. This study aimed to screen bacterial isolates for HA production, characterize favorable fermentation conditions, and evaluate the inhibitory effect of bacterial HA on cancer cell lines.
A total of 108 bacterial isolates from diverse sources were screened for HA production using HPLC, turbidimetric, and carbazole determination methods. Among the HA-producing isolates, Klebsiella pneumoniae H15 isolated from an animal feces sample, was superior in HA production. The strain was characterized based on its morphological, cultural, and biochemical characteristics. Molecular identification using 16S rDNA sequencing and phylogenetic analysis confirmed its identity. Fermentation conditions, including pH, temperature, time, and agitation rate, were optimized to maximize HA production. The basal medium, comprising sucrose (7.0%) as carbon source and combined yeast extract with peptone (1.25% each) as nitrogen substrate, favored the highest HA production at pH 8.0, for 30 h, at 30 °C, under shaking at 180 rpm. The average maximized HA concentration reached 1.5 g L. Furthermore, bacterial HA exhibited a significant inhibitory effect on three cancer cell lines (MCF-7, HepG-2 and HCT), with the lowest concentration ranging from 0.98-3.91 µg mL.
K. pneumoniae H15, isolated from animal feces demonstrated promising potential for HA production. The most favorable fermentation conditions led to a high HA production. The inhibitory effect of bacterial HA on cancer cell lines highlights its potential therapeutic applications. These findings contribute to a broader understanding and utilization of HA in various industries and therapeutic applications.
透明质酸（HA）因其独特的物理、化学和生物学特性而备受关注，广泛应用于各个行业。本研究旨在筛选产 HA 的细菌分离株，确定有利的发酵条件，并评估细菌 HA 对癌细胞系的抑制作用。
使用 HPLC、浊度和咔唑测定法，从各种来源筛选了 108 株细菌分离株以生产 HA。在产 HA 的分离株中，从动物粪便样本中分离出的肺炎克雷伯菌 H15 在 HA 生产方面表现出色。该菌株根据其形态、培养和生化特征进行了表征。16S rDNA 测序和系统发育分析的分子鉴定证实了其身份。优化了发酵条件，包括 pH、温度、时间和搅拌速度，以最大限度地提高 HA 产量。基础培养基由蔗糖（7.0%）作为碳源和酵母提取物与蛋白胨（各 1.25%）组合作为氮源，在 pH 8.0、30°C、180rpm 摇床条件下，30h 后，HA 产量最高。平均最大 HA 浓度达到 1.5g/L。此外，细菌 HA 对三种癌细胞系（MCF-7、HepG-2 和 HCT）表现出显著的抑制作用，最低浓度范围为 0.98-3.91μg/mL。
从动物粪便中分离出的肺炎克雷伯菌 H15 具有产 HA 的巨大潜力。最有利的发酵条件导致 HA 产量高。细菌 HA 对癌细胞系的抑制作用突出了其在治疗中的潜在应用。这些发现有助于更广泛地理解和利用 HA 在各个行业和治疗应用中的应用。
