Pahalagedara Amila Srilal Nawarathna Weligala, Flint Steve, Palmer Jon, Subbaraj Arvind, Brightwell Gale, Gupta Tanushree Barua
Food Assurance team, AgResearch Ltd., Hopkirk Research Institute, Massey University, Palmerston North, New Zealand.
School of Food and Advanced Technology, Massey University, Palmerston North, New Zealand.
Front Microbiol. 2020 Dec 4;11:608998. doi: 10.3389/fmicb.2020.608998. eCollection 2020.
The rise of antimicrobial resistant bacteria has fast-tracked the exploration for novel antimicrobial compounds. Reports on antimicrobial producing soil anaerobes such as spp. are very limited. In the present study, the antimicrobial activity of soil enriched conditioned/spent media (CMs) against , and was assessed by turbidimetric growth inhibition assay. Our results highlighted the antimicrobial potential of soil enriched conditioned media against pathogenic and spoilage bacteria. Farm 4 soil conditioned medium (F4SCM) demonstrated a greater growth inhibition activity against all three tested microorganisms in comparison to other soil conditioned media. Non-targeted metabolite profiling of all soil conditioned media revealed distinctive polar and intermediate-polar metabolites in F4SCM, consistent with its strong antimicrobial property. Moreover, 539 significantly abundant metabolites including some unique features were detected in F4SCM suggesting its substantial and specialized chemical diversity. This study putatively identified seven significantly high metabolites in F4SCM; 3-hydroxyphenylacetic acid, γ-aminobutyric acid, creatine, tryptamine, and 2-hydroxyisocaproic acid. Tryptamine and 2-hydroxyisocaproic acid were previously reported to have antimicrobial properties. The present study shows that soil spp. are a promising group of bacteria producing metabolites with antimicrobial activity and provides future prospects for clostridial antimicrobial discovery within their metabolic diversity.
抗微生物耐药细菌的出现加速了新型抗微生物化合物的探索。关于产抗微生物物质的土壤厌氧菌（如 属）的报道非常有限。在本研究中，通过比浊法生长抑制试验评估了富含土壤 的条件培养基/用过的培养基（CMs）对 、 和 的抗微生物活性。我们的结果突出了富含土壤 的条件培养基对致病和腐败细菌的抗微生物潜力。与其他土壤条件培养基相比，农场4土壤条件培养基（F4SCM）对所有三种测试微生物均表现出更大的生长抑制活性。对所有土壤条件培养基进行的非靶向代谢物谱分析揭示了F4SCM中独特的极性和中等极性代谢物，与其强大的抗微生物特性一致。此外，在F4SCM中检测到539种显著丰富的代谢物，包括一些独特特征，表明其具有丰富且特殊的化学多样性。本研究推测鉴定出F4SCM中的七种显著高丰度代谢物；3-羟基苯乙酸、γ-氨基丁酸、肌酸、色胺和2-羟基异己酸。色胺和2-羟基异己酸此前被报道具有抗微生物特性。本研究表明，土壤 属细菌是一类有前景的产具有抗微生物活性代谢物的细菌，并为梭菌抗微生物发现其代谢多样性提供了未来前景。
