Isolation, characterization and strain selection of a Paenibacillus species for use as a probiotic to aid in ruminal methane mitigation, nitrate/nitrite detoxification and food safety. (September 2018)

• Record Type: Journal Article
• Authors: Latham, Elizabeth A.; Pinchak, William E.; Trachsel, Julian; Allen, Heather K.; Callaway, Todd R.; Nisbet, David J.; Anderson, Robin C.
• Is Part Of: Bioresource technology. Volume 263(2018)
• Page Start: 358
• Page End: 364
• Publication Date: 2018-09
• Subjects: Nitrate -- Nitrite -- Nitrite toxicity -- Paenibacillus -- Rumen methanogenesis; Biomass -- Periodicals; Biomass energy -- Periodicals; Bioremediation -- Periodicals; Agricultural wastes -- Periodicals; Factory and trade waste -- Periodicals; Organic wastes -- Periodicals; Bioénergie -- Périodiques; Déchets agricoles -- Périodiques; Déchets industriels -- Périodiques; Déchets organiques -- Périodiques; Déchets (Combustible) -- Périodiques; 662.88
• DOI: 10.1016/j.biortech.2018.04.116
• Languages: English
• ISSNs: 0960-8524

Abstract

Highlights: A denitrifying Paenibacillus, designated 79R4, was isolated from the bovine rumen. Strain 79R4 was selected for enhanced nitrite-metabolizing activity. Co-addition of strain 79R4 with nitrate to rumen cultures decreased methanogenesis. Co-addition of strain 79R4 with nitrate to rumen cultures detoxified nitrite. The spore-forming and nitrite-detoxifying ability of 79R4 make it a good probiotic. Abstract: The effects of dietary nitrate and Paenibacillus 79R4 (79R4), a denitrifying bacterium, when co-administered as a probiotic, on methane emissions, nitrate and nitrite-metabolizing capacity and fermentation characteristics were studied in vitro . Mixed populations of rumen microbes inoculated with 79R4 metabolized all levels of nitrite studied after 24 h in vitro incubation. Results from in vitro simulations resulted in up to 2 log10 colony forming unit reductions in E. coli O157:H7 and Campylobacter jejuni when these were co-cultured with 79R4. Nitrogen gas was the predominant final product of nitrite reduction by 79R4. When tested with nitrate-treated incubations of rumen microbes, 79R4 inoculation (provided to achieve 10 6 cells/mL rumen fluid volume) complemented the ruminal methane-decreasing potential of nitrate ( P < 0.05) while concurrently increasing fermentation efficiency and enhancing ruminal nitrate and nitrite-metabolizing activity ( P < 0.05) compared to untreated and nitrate only-treated incubations.