Biocontrol of Aspergillus flavus in Ensiled Sorghum by Water Kefir Microorganisms

Abstract

The capacity of microorganisms from water kefir (WK) to control Aspergillus flavus growth during the aerobic phase of ensiled sorghum grains was determined. Sorghum inoculated with A. flavus was treated with filter-sterilized and non-sterilized water kefir, ensiled, and incubated 7 days at 25 °C. A. flavus growth was quantified by qPCR after incubation. Mold growth was inhibited in the presence of water kefir while no inhibition was observed when filter-sterilized water kefir was applied, demonstrating the relevant role of the microorganisms in the kefir water in the biocontrol process. Fungal and bacterial diversity in treated sorghum mini-silos was analyzed by high-throughput sequencing. Firmicutes was the predominant bacterial phyla and Lactobacillus represented the most abundant genus, while Ascomycota was the predominant fungal phyla with Saccharomyces and Pichia as the major genera. Bacterial and yeast counts before and after incubation indicated that the microbial community obtained from WK was able to grow in the sorghum mini-silos in the presence of A. flavus. Results of the present work indicate that the use of a mixed inoculum of microorganisms present in WK may represent an alternative management practice to avoid the growth of A. flavus in ensiled sorghum grains and the concomitant contamination with aflatoxins.

Microbiota succession during aerobic stability of maize silage inoculated with Lentilactobacillus buchneri NCIMB 40788 and Lentilactobacillus hilgardii CNCM‐I‐4785

“…The fungal population was mainly composed of the yeasts Saccharomyces and Kazachstania, but with a higher abundance of Bionectriaceae in some samples of LB + LH silages. Bionectriaceae has rarely been reported in corn silage but has been observed in sorghum before ensiling (Gonda et al, 2019). Interestingly, in this family,…”

“…The fungal population was mainly composed of the yeasts Saccharomyces and Kazachstania , but with a higher abundance of Bionectriaceae in some samples of LB + LH silages. Bionectriaceae has rarely been reported in corn silage but has been observed in sorghum before ensiling (Gonda et al, 2019). Interestingly, in this family, the Clonostachys related‐OTU is an epiphytic mycoparasitic fungus that can be used for biocontrol of Fusarium graminearum (Gimeno et al, 2019), and also has the enzymatic potential to degrade zearalenone (Ogunade et al, 2018).…”

Yeasts and Bacterial Consortia from Kefir Grains Are Effective Biocontrol Agents of Postharvest Diseases of Fruits

“…Kefir grains are complex biological entities comprising diverse species of microorganisms) that have been used for centuries to create fermented drink products from either milk or water. More recently, studies have shown that the microorganisms present in probiotic water kefir have a capacity to act biocontrol agents in stored grains [38]. Utilizing such consortia, or the organisms within them, for postharvest biocontrol, would represent a novel approach to providing both decay control and a source of probiotics.…”

Effect of Different Kefir Source on Fermentation, Aerobic Stability, and Microbial Community of Alfalfa Silage

“…Kefir has also received considerable scholarly attention in recent years due to its antioxidant, anti-inflammatory, antifungal, antibacterial specialties, and various pharmaceutical attributes [12][13][14]. Previous research evaluating the effect of kefir microorganisms on aerobic spoilage of sorghum and wheat-straw silages also strengthens these assumptions [15,16]. However, there is a notable lack of high-quality research focusing specifically on fermentation characteristics, aerobic stability, and the microbial community of alfalfa silages inoculated with different kefir sources.…”