Tyagi Amrish Kumar, Kumar Sachin, Choudhury Prasanta Kumar, Tyagi Bhawna, Tyagi Nitin
Rumen Biotechnology Lab, Animal Nutrition Division, ICAR-National Dairy Research Institute, Karnal, Haryana 132001, India.
Gut Microbial Function, CSIRO Agriculture and Food, Queensland Bioscience Precinct, St Lucia, Brisbane 4067, Australia.
Asian-Australas J Anim Sci. 2020 Aug;33(8):1233-1241. doi: 10.5713/ajas.19.0080. Epub 2019 Aug 23.
The present investigation was aimed to explore the potential of lactobacilli for conjugated linoleic acid (CLA) production, isolated from rumen fluid samples of lactating goats.
A total of 64 isolates of lactobacilli were obtained using deMan-Rogosa-Sharpe (MRS) agar from rumen fluid of goats and further subjected to morphological and biochemical characterizations. Isolates found as gram-positive, catalase negative rods were presumptively identified as Lactobacillus species and further confirmed by genus specific polymerase chain reaction (PCR). The phylogenetic tree was constructed from the nucleotide sequences using MEGA6.
Out of the 64 isolates, 23 isolates were observed positive for CLA production by linoleate isomerase gene-based amplification and quantitatively by UV-spectrophotometric assay for the conversion of linoleic acid to CLA as well as gas chromatography-based assay. In all Lactobacillus species cis9, trans11 isomer was observed as the most predominant CLA isomer. These positive isolates were identified by 16S rRNA gene-based PCR sequencing and identified to be different species of L. ingluviei (2), L.salivarius (2), L. curvatus (15), and L. sakei (4).
The findings of the present study concluded that lactic acid bacteria isolated from ruminal fluid samples of goat have the potential to produce bioactive CLA and may be applied as a direct fed microbial to enhance the nutraceutical value of animal food products.
本研究旨在探索从泌乳山羊瘤胃液样本中分离出的乳酸杆菌产生共轭亚油酸(CLA)的潜力。
使用德氏乳杆菌-罗格斯-夏普(MRS)琼脂从山羊瘤胃液中获得了总共64株乳酸杆菌分离株,并进一步进行了形态学和生化特征分析。发现为革兰氏阳性、过氧化氢酶阴性的杆菌初步鉴定为乳酸杆菌属,并通过属特异性聚合酶链反应(PCR)进一步确认。使用MEGA6从核苷酸序列构建系统发育树。
在64株分离株中,通过基于亚油酸异构酶基因的扩增以及通过紫外分光光度法测定亚油酸转化为CLA以及基于气相色谱法测定,观察到23株分离株CLA产生呈阳性。在所有乳酸杆菌属物种中,顺式9,反式11异构体被观察为最主要的CLA异构体。这些阳性分离株通过基于16S rRNA基因的PCR测序进行鉴定,并鉴定为不同种的 ingluviei乳杆菌(2株)、唾液乳杆菌(2株)、弯曲乳杆菌(15株)和清酒乳杆菌(4株)。
本研究结果得出结论,从山羊瘤胃液样本中分离出的乳酸菌具有产生生物活性CLA的潜力,并且可以用作直接投喂微生物以提高动物食品的营养保健价值。