Shafiq Johar, P. Puvanasundram, C. R. de Cruz, Chou Min Chong, Ina Salwany Md Yasin, K. C. Lim, Noordiyana Mat Noordin, M. Karim
{"title":"In-vitro Inhibitory Activities of Potential Probiotic Isolated from Pangasius nasutus against Aeromonas hydrophila and Streptococcus agalactiae","authors":"Shafiq Johar, P. Puvanasundram, C. R. de Cruz, Chou Min Chong, Ina Salwany Md Yasin, K. C. Lim, Noordiyana Mat Noordin, M. Karim","doi":"10.17576/jsm-2024-5301-08","DOIUrl":null,"url":null,"abstract":"In aquaculture, using probiotics is crucial for strengthening the immune system and encouraging the growth and survival of many aquatic organisms, including the Pangasius species. This approach is particularly significant given the impact of bacterial diseases on Pangasius survival. This study aimed to assess the effectiveness of probiotics isolated from Pangasius nasutus as alternatives to antibiotics for combating infections caused by Aeromonas hydrophila and Streptococcus agalactiae. Potential bacteria were isolated from the intestine and stomach of healthy P. nasutus. Seventy probiotic strains were successfully isolated and further screened using A. hydrophilaand S. agalactiae as pathogens in an in vitro disc diffusion assay. Preliminary screenings indicated that five probiotic strains inhibited the growth of A. hydrophila. Stomach-derived strain S1 and intestine-derived strain L1 suppressed A. hydrophila growth with inhibition zones of 10.5±1 mm and 8.5±1 mm, respectively. Likewise, strains L2, L8, and L12 from the intestine showed inhibitory zones of 6.0±1 mm, 6.5±1 mm, and 6.0±1 mm, respectively. Of these, only L12 inhibited the growth of S. agalactiae with a clear zone of 5.0±1 mm. In the elimination of pathogenic strains, potential strains S1 and L1 did not grow on the Aeromonas isolation medium. Co-culture assays demonstrated that both potential strains significantly inhibited Aeromonas hydrophila growth at concentrations of 106 and 108 CFU mL-1 over 48- and 96-hour periods, respectively. The potential bacterial strains were identified using 16s rRNA gene sequencing and were classified as follows: S1 - Lactococcus lactis, L1 - Weissella confusa, L2 - Cosenzaea myxofaciens, L8 - Lactococcus garvieae, and L12 - Plesiomonas shigelloides. Strain S1 L. lactis and strain L1 W. confusa are suggested for further evaluation and acquired additional research to fully elucidate their mechanisms and potential as probiotics.","PeriodicalId":21366,"journal":{"name":"Sains Malaysiana","volume":null,"pages":null},"PeriodicalIF":0.7000,"publicationDate":"2024-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Sains Malaysiana","FirstCategoryId":"103","ListUrlMain":"https://doi.org/10.17576/jsm-2024-5301-08","RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"MULTIDISCIPLINARY SCIENCES","Score":null,"Total":0}
引用次数: 0
Abstract
In aquaculture, using probiotics is crucial for strengthening the immune system and encouraging the growth and survival of many aquatic organisms, including the Pangasius species. This approach is particularly significant given the impact of bacterial diseases on Pangasius survival. This study aimed to assess the effectiveness of probiotics isolated from Pangasius nasutus as alternatives to antibiotics for combating infections caused by Aeromonas hydrophila and Streptococcus agalactiae. Potential bacteria were isolated from the intestine and stomach of healthy P. nasutus. Seventy probiotic strains were successfully isolated and further screened using A. hydrophilaand S. agalactiae as pathogens in an in vitro disc diffusion assay. Preliminary screenings indicated that five probiotic strains inhibited the growth of A. hydrophila. Stomach-derived strain S1 and intestine-derived strain L1 suppressed A. hydrophila growth with inhibition zones of 10.5±1 mm and 8.5±1 mm, respectively. Likewise, strains L2, L8, and L12 from the intestine showed inhibitory zones of 6.0±1 mm, 6.5±1 mm, and 6.0±1 mm, respectively. Of these, only L12 inhibited the growth of S. agalactiae with a clear zone of 5.0±1 mm. In the elimination of pathogenic strains, potential strains S1 and L1 did not grow on the Aeromonas isolation medium. Co-culture assays demonstrated that both potential strains significantly inhibited Aeromonas hydrophila growth at concentrations of 106 and 108 CFU mL-1 over 48- and 96-hour periods, respectively. The potential bacterial strains were identified using 16s rRNA gene sequencing and were classified as follows: S1 - Lactococcus lactis, L1 - Weissella confusa, L2 - Cosenzaea myxofaciens, L8 - Lactococcus garvieae, and L12 - Plesiomonas shigelloides. Strain S1 L. lactis and strain L1 W. confusa are suggested for further evaluation and acquired additional research to fully elucidate their mechanisms and potential as probiotics.
期刊介绍:
Sains Malaysiana is a refereed journal committed to the advancement of scholarly knowledge and research findings of the several branches of science and technology. It contains articles on Earth Sciences, Health Sciences, Life Sciences, Mathematical Sciences and Physical Sciences. The journal publishes articles, reviews, and research notes whose content and approach are of interest to a wide range of scholars. Sains Malaysiana is published by the UKM Press an its autonomous Editorial Board are drawn from the Faculty of Science and Technology, Universiti Kebangsaan Malaysia. In addition, distinguished scholars from local and foreign universities are appointed to serve as advisory board members and referees.