| 摘要: |
| 本研究旨在从广西北部湾红树林土壤来源可培养原核生物中筛选出具有显著抗氧化活性的菌株，并通过研究它们的抗氧化活性评估其应用潜力。采用过氧化氢胁迫实验进行抗氧化活性菌株的初筛；通过ABTS[2,2'-Azino-bis (3-ethylbenzothiazoline- 6-sulfonic acid)]自由基清除实验和抗氧化化合物总类黄酮（TFC）产量测定进一步验证菌株的抗氧化活性；对筛选得到的抗氧化活性菌株进行16S rRNA基因测序，明确它们的种属；通过质谱分析活性菌株所产与抗氧化活性相关的次生代谢产物，分析它们的抗氧化机制；将具有抗氧化活性潜能的菌株与大肠杆菌、酵母共培养，评估其在不同菌株氧化胁迫耐受性中的保护作用，初步探讨它们的应用潜力。结果表明，从北部湾红树林土壤可培养原核生物中筛选得到12株具有显著抗氧化活性的菌株，其中H1831、H501和B2676三株菌株的自由基清除能力最稳定。进一步分析发现H1831的总类黄酮产量最高，B2676次之；16S rRNA基因序列的比对分析发现，H1831、H501和B2676分别隶属于黄腐杆菌Flavihumibacter属、芽孢杆菌Bacillus属和链霉菌Streptomyces属；基于质谱的代谢物指纹图谱分析表明，H1831有潜力生产多种生物碱和萜类化合物，这些化合物可能是其潜在的抗氧化活性成分；在共培养实验中，B2676可显著提升大肠杆菌和酵母的过氧化氢耐受性。综上所述，本研究从广西北部湾红树林土壤中分离得到多株具有较强抗氧化活性潜能的菌株，为开发微生物源天然抗氧化剂提供了新的生物资源。 |
| 关键词: 北部湾红树林 可培养原核生物 抗氧化活性 活性化合物 |
| DOI： |
| 投稿时间：2026-01-25修订日期：2026-04-15 |
| 基金项目:1. 广西科技基地和人才专项资助（桂科AD25069077，GKE-ZZ202511）2. 国家自然科学基金（82260689） |
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| This research was supported by Guangxi Science and Technology Program (Grant NO.AD25069077 and NO.GKE-ZZ202511) and National natural science foundation of China (82260689).Discovery and activity evaluation of antioxidant strains isolated from mangrove sediments in Beibu Gulf |
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Liang Tingting1, Pan Xinli2, Lu Yaomin1, Huang Jinglian1, ZHOU Xiaoying1, Hu Wenjin2
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| (1.Institute of Life Sciences(Guangxi Medical University);2.Guangxi Academy of Sciences College of Ecology and Environment) |
| Abstract: |
| This study aimed to isolate culturable prokaryotes exhibiting significant antioxidant potential from mangrove sediments in Beibu Gulf and evaluate their application potential based on their antioxidant properties. An initial screening for antioxidant-active strains was conducted using a hydrogen peroxide (H2O2) stress assay. The antioxidant activity of the strains was further validated through an ABTS [2,2'-Azino-Bis (3-Ethylbenzothiazoline-6-Sulfonic Acid)] radical scavenging assay and by measuring the total flavonoid content (TFC) as an indicator of antioxidant compound production. Strains with stable antioxidant activity were identified based on the analysis of 16S rRNA gene sequences. LC-MS-based metabolomics was employed to analyze secondary metabolites potentially related to their antioxidant activity and to elucidate the underlying mechanisms. The strains with potential antioxidant activity were co-cultured with Escherichia coli and Saccharomyces cerevisiae to evaluate their protective effects on oxidative stress tolerance in different strains, and to preliminarily explore their application potential. The results showed that twelve strains with significant antioxidant activity were isolated from the culturable mangrove sediments-derived prokaryotes. Among them, strains H1831, H501, and B2676 exhibited the most stable radical scavenging capacity. Strain H1831 also produced the highest TFC, followed by B2676. Comparative analysis of 16S rRNA gene sequences revealed that H1831, H501, and B2676 belong to the genera Flavihumibacter, Bacillus, and Streptomyces, respectively. MS-based metabolomics indicated that strain H1831 has the potential to produce various alkaloids and terpenoids, which may be its potential antioxidant active components.. In co-culture experiments, strain B2676 significantly enhanced the hydrogen peroxide tolerance of both E. coli and S. cerevisiae. In summary, this study isolated multiple strains with strong antioxidant activity potential from the mangrove sediments in Beibu Gulf, providing novel biological resources for the development of microbial-derived natural antioxidants. |
| Key words: Beibu Gulf mangrove Culturable prokaryotes Antioxidant activity Bioactive compounds |
