Khan Abdul Latif, Gilani Syed Abdullah, Waqas Muhammad, Al-Hosni Khadija, Al-Khiziri Salima, Kim Yoon-Ha, Ali Liaqat, Kang Sang-Mo, Asaf Sajjad, Shahzad Raheem, Hussain Javid, Lee In-Jung, Al-Harrasi Ahmed
UoN Chair of Oman's Medicinal Plants & Marine Natural Products, University of Nizwa, Nizwa 616, Oman.
Department of Biological Sciences & Chemistry, University of Nizwa, Nizwa 616, Oman.
J Zhejiang Univ Sci B. 2017;18(2):125-137. doi: 10.1631/jzus.B1500271.
Medicinal plants have been used by marginal communities to treat various ailments. However, the potential of endophytes within these bio-prospective medicinal plants remains unknown. The present study elucidates the endophytic diversity of medicinal plants (Caralluma acutangula, Rhazya stricta, and Moringa peregrina) and the endophyte role in seed growth and oxidative stress. Various organs of medicinal plants yielded ten endophytes, which were identified as Phoma sp. (6 isolates), Alternaria sp. (2), Bipolaris sp. (1), and Cladosporium sp. (1) based on 18S rDNA sequencing and phylogenetic analysis. The culture filtrates (CFs; 25%, 50%, and 100% concentrations) from these endophytes were tested against the growth of normal and dwarf mutant rice lines. Endophytic CF exhibited dose-dependent growth stimulation and suppression effects. CF (100%) of Phoma sp. significantly increased rice seed germination and growth compared to controls and other endophytes. This growth-promoting effect was due to the presence of indole acetic acid in endophytic CF. The gas chromatography/mass spectrometry (GC/MS) analysis showed the highest indole acetic acid content ((54.31±0.21) µmol/L) in Bipolaris sp. In addition, the isolate of Bipolaris sp. exhibited significantly higher radical scavenging and anti-lipid peroxidation activity than the other isolates. Bipolaris sp. and Phoma sp. also exhibited significantly higher flavonoid and phenolic contents. The medicinal plants exhibited the presence of bio-prospective endophytic strains, which could be used for the improvement of crop growth and the mitigation of oxidative stresses.
边缘社区一直利用药用植物治疗各种疾病。然而，这些具有生物勘探潜力的药用植物中内生菌的潜力仍不为人知。本研究阐明了药用植物（尖棱麒麟、刺山柑、和奇异辣木）的内生菌多样性以及内生菌在种子生长和氧化应激中的作用。药用植物的各个器官产生了10种内生菌，基于18S rDNA测序和系统发育分析，它们被鉴定为茎点霉属（6个分离株）、链格孢属（2个）、离蠕孢属（1个）和枝孢属（1个）。测试了这些内生菌的培养滤液（CFs；浓度分别为25%、50%和100%）对正常和矮化突变水稻品系生长的影响。内生菌CF表现出剂量依赖性的生长刺激和抑制作用。与对照和其他内生菌相比，茎点霉属的CF（100%）显著提高了水稻种子的发芽率和生长。这种促生长作用归因于内生菌CF中存在吲哚乙酸。气相色谱/质谱（GC/MS）分析表明，离蠕孢属中吲哚乙酸含量最高（(54.31±0.21) µmol/L）。此外，离蠕孢属分离株表现出比其他分离株显著更高的自由基清除和抗脂质过氧化活性。离蠕孢属和茎点霉属还表现出显著更高的类黄酮和酚类含量。这些药用植物中存在具有生物勘探潜力的内生菌株，可用于促进作物生长和减轻氧化应激。
