Probiotic properties of Bacillus licheniformis HN318 and comparison of the effects of its bacterial cells and cultures on growth, immunity and disease resistance of hybrid grouper (Epinephelus polyphekadion♂ × Epinephelus fuscoguttatus♀)
{"title":"Probiotic properties of Bacillus licheniformis HN318 and comparison of the effects of its bacterial cells and cultures on growth, immunity and disease resistance of hybrid grouper (Epinephelus polyphekadion♂ × Epinephelus fuscoguttatus♀)","authors":"Zhenjie Cao, Qiaoli Yang, Aie Kang, Guotao Wang, Pengshuo Li, Guiping Qiu, Jinge Wang, Chunsheng Liu, Yun Sun","doi":"10.3389/fmars.2025.1548955","DOIUrl":null,"url":null,"abstract":"Introduction<jats:italic>Bacillus</jats:italic> species are probiotics commonly utilized in aquaculture to enhance aquatic animal growth, inhibit pathogens, and strengthen immunity. However, research comparing the effects of probiotic bacterial cells and cultures is limited. This study aimed to evaluate the probiotic potential of <jats:italic>Bacillus licheniformis</jats:italic> strain HN318 and compare its impact on growth, immunity, and disease resistance in hybrid grouper when administered as bacterial cells or cultures.MethodsThe study involved assessing the auto-aggregation capability, gastrointestinal stress resistance, and safety of HN318. Enzymatic activities and antibacterial properties of HN318 cultures and bacterial cells were also compared. Hybrid grouper were fed with HN318 cultures and bacterial cells for 8 weeks, and their growth, feed utilization, immune responses, and survival rates upon challenge with <jats:italic>Vibrio harveyi</jats:italic> were evaluated. Additionally, the expression of immune-related genes was analyzed.ResultsHN318 exhibited high auto-aggregation and gastrointestinal stress resistance, and was found to be safe for use in aquaculture. Cultures of HN318 displayed higher protease, amylase, and antibacterial activities compared to bacterial cells. Both forms significantly improved growth and feed utilization in hybrid grouper. Notably, HN318 cultures induced higher levels of immune enzymes and activities, and provided better protection against <jats:italic>V. harveyi</jats:italic> challenge, with a higher relative percent survival compared to bacterial cells. Furthermore, HN318 cultures upregulated the expression of immune-related genes more than bacterial cells.DiscussionThis study highlights the potential of both HN318 cultures and bacterial cells as immune enhancers for hybrid grouper. However, HN318 cultures demonstrated superior probiotic properties, including higher enzymatic activities, antibacterial properties, and immunomodulatory effects. These findings provide new insights and references for the diverse application forms of probiotics in aquaculture, suggesting that cultures may be more effective than bacterial cells in enhancing the health and performance of aquatic animals.","PeriodicalId":12479,"journal":{"name":"Frontiers in Marine Science","volume":"50 1","pages":""},"PeriodicalIF":2.8000,"publicationDate":"2025-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Frontiers in Marine Science","FirstCategoryId":"99","ListUrlMain":"https://doi.org/10.3389/fmars.2025.1548955","RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"MARINE & FRESHWATER BIOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
IntroductionBacillus species are probiotics commonly utilized in aquaculture to enhance aquatic animal growth, inhibit pathogens, and strengthen immunity. However, research comparing the effects of probiotic bacterial cells and cultures is limited. This study aimed to evaluate the probiotic potential of Bacillus licheniformis strain HN318 and compare its impact on growth, immunity, and disease resistance in hybrid grouper when administered as bacterial cells or cultures.MethodsThe study involved assessing the auto-aggregation capability, gastrointestinal stress resistance, and safety of HN318. Enzymatic activities and antibacterial properties of HN318 cultures and bacterial cells were also compared. Hybrid grouper were fed with HN318 cultures and bacterial cells for 8 weeks, and their growth, feed utilization, immune responses, and survival rates upon challenge with Vibrio harveyi were evaluated. Additionally, the expression of immune-related genes was analyzed.ResultsHN318 exhibited high auto-aggregation and gastrointestinal stress resistance, and was found to be safe for use in aquaculture. Cultures of HN318 displayed higher protease, amylase, and antibacterial activities compared to bacterial cells. Both forms significantly improved growth and feed utilization in hybrid grouper. Notably, HN318 cultures induced higher levels of immune enzymes and activities, and provided better protection against V. harveyi challenge, with a higher relative percent survival compared to bacterial cells. Furthermore, HN318 cultures upregulated the expression of immune-related genes more than bacterial cells.DiscussionThis study highlights the potential of both HN318 cultures and bacterial cells as immune enhancers for hybrid grouper. However, HN318 cultures demonstrated superior probiotic properties, including higher enzymatic activities, antibacterial properties, and immunomodulatory effects. These findings provide new insights and references for the diverse application forms of probiotics in aquaculture, suggesting that cultures may be more effective than bacterial cells in enhancing the health and performance of aquatic animals.
期刊介绍:
Frontiers in Marine Science publishes rigorously peer-reviewed research that advances our understanding of all aspects of the environment, biology, ecosystem functioning and human interactions with the oceans. Field Chief Editor Carlos M. Duarte at King Abdullah University of Science and Technology Thuwal is supported by an outstanding Editorial Board of international researchers. This multidisciplinary open-access journal is at the forefront of disseminating and communicating scientific knowledge and impactful discoveries to researchers, academics, policy makers and the public worldwide.
With the human population predicted to reach 9 billion people by 2050, it is clear that traditional land resources will not suffice to meet the demand for food or energy, required to support high-quality livelihoods. As a result, the oceans are emerging as a source of untapped assets, with new innovative industries, such as aquaculture, marine biotechnology, marine energy and deep-sea mining growing rapidly under a new era characterized by rapid growth of a blue, ocean-based economy. The sustainability of the blue economy is closely dependent on our knowledge about how to mitigate the impacts of the multiple pressures on the ocean ecosystem associated with the increased scale and diversification of industry operations in the ocean and global human pressures on the environment. Therefore, Frontiers in Marine Science particularly welcomes the communication of research outcomes addressing ocean-based solutions for the emerging challenges, including improved forecasting and observational capacities, understanding biodiversity and ecosystem problems, locally and globally, effective management strategies to maintain ocean health, and an improved capacity to sustainably derive resources from the oceans.