Selection of Bacteriocinogenic Bacillus spp. from Traditional Fermented Korean Food Products with Additional Beneficial Properties

Gee Hyeun Choi,Svetoslav Dimitrov Todorov,Joanna Ivy Irorita Fugaban,Wilhelm Heinrich Holzapfel,Jorge Enrique Vazquez Bucheli,Clarizza May Dioso

doi:10.3390/fermentation7040271

Gee Hyeun Choi, Svetoslav Dimitrov Todorov + Show 4 more

Open Access

https://doi.org/10.3390/fermentation7040271

Copy DOI

Journal: Fermentation	Publication Date: Nov 21, 2021
Citations: 3	License type: CC BY 4.0

Affiliation: Handong Global University

Abstract

Two Bacillus spp. isolated from kimchi, Bacillus tequilensis ST816CD and Bacillus subtilis ST830CD, were characterized for their antimicrobial properties and safety. The proteinaceous nature of their inhibitory metabolites was confirmed after exposure to proteolytic enzymes, resulting in partial loss of the antimicrobial effect. This indicated that different non-proteinaceous antimicrobial substances may also be produced by these strains. This hypothesis was later confirmed when genes associated with the production of surfactants were detected in their DNA. The expressed antimicrobial metabolites were not affected by treatment at different temperatures and pH levels, including exposure to selected chemicals. Their strong adherence to susceptible pathogens was not significantly affected by different temperatures, chemicals, or pH values. Both Bacillus strains showed inhibitory activity against clinical and food-associated pathogens, including Listeria monocytogenes ATCC 15313, and some Staphylococcus species. Several genes associated with the production of antimicrobial metabolites were detected, but key virulence and beneficial genes were not present in these strains. Even though only B. tequilensis ST816CD displayed γ-hemolysin production, both selected strains were found to produce gelatinase and biogenic amines, which are considered as either potential virulence- or health-related factors. Moreover, the strains were susceptible to a variety of antibiotics except for the penicillin G [1 IU/disc] resistance of B. tequilensis ST816CD. Both strains showed proteolytic activity. Additionally, both strains showed low hydrophobicity based on bacterial adherence measured by hydrocarbons (n-hexadecane).

Highlights

In the search for a healthier lifestyle, traditional fermented food products have become a major area for “strain-prospecting”
Different bacterial species involved in food fermentations were evaluated for their beneficial properties and for potential application in food biotechnology and as probiotic candidates for human and animal applications
The original aim of this study was to isolate lactic acid bacteria (LAB) from various fermented food products, the preliminary profiles of the isolated strains indicate that bacilli could be considered as major inhabitants of these Korean fermented food products, since more than 80% of the evaluated plates were covered by typical Bacillus colonies

Summary

Introduction

In the search for a healthier lifestyle, traditional fermented food products have become a major area for “strain-prospecting”. Representatives of Bacillus spp. constitute great potential for research towards diverse applications in pharmaceutical and food processing industries [3]; this is based on their established roles in the production of different traditional fermented food products [4]. Such strain mixtures were empirically “used” as starter cultures in the traditional production of fermented food products in Africa [4], Japan [5], and India [6]. These include the species Bacillus anthracis and Bacillus cereus, and strains of Bacillus licheniformis that are associated with serious health conditions of humans and animals [13,14]

Objectives

Methods

Results

Discussion

Conclusion