Priestia megaterium reduces hydrogen sulfide level in swine manure potentially through an assimilatory mechanism and microbiota modulation
Year: 2026
Type: article
Abstract: Swine farming is an important agricultural industry; however, managing manure and associated malodorous emissions presents considerable challenges for intensive animal farmers, nearby communities, and environmental regulatory agencies (Ma et al. 2021 ; Song 2024 ). The major compounds causing swine odors include volatile fatty acids (VFAs), phenols, indoles, ammonia (NH 3 ), and volatile sulfur compounds (VSCs) (Jo et al. 2015 ). The production of these malodorous compounds is influenced by the physicochemical properties, carbon source material, and microbiome of the manure (Jo et al. 2015 ). Among them, hydrogen sulfide (H 2 S), characterized by its distinctive "rotten egg" odor and potential toxicity at high concentrations, is one of the most problematic gases produced during the anaerobic decomposition of swine manure (Guarrasi et al. 2015 ; Brglez 2021 ; Song 2024 ). Low concentrations of H 2 S produce a manually detectable unpleasant odor, whereas H 2 S concentrations > 100 ppm pose significant health risks to animals and farm workers (Guarrasi et al. 2015 ; Park et al. 2016 ; Brglez 2021 ). Its low concentrations affect pigs inducing the development of symptoms such as photophobia (light sensitivity), anorexia (loss of appetite), and increased nervousness or agitation (Brglez 2021 ; Hossain et al. 2024 ); exposure to 50–200 ppm H 2 S induces more severe clinical signs, including vomiting and diarrhea (Brglez 2021 ), with prolonged or elevated exposure further compromising animal growth and performance. For instance, weaning pigs exposed to H 2 S at 5 mg/m 3 H 2 S (approximately 3.4 ppm) for 28 days exhibited reduced average daily gain and feed intake, along with an increased incidence of diarrhea and disrupted gut microbiota (Cui et al. 2021 ). Higher concentrations of H 2 S exposure can induce respiratory distress and lung lesions; the extreme outcomes of H 2 S exposure include neurological complications such as olfactory dysfunction and death due to respiratory paralysis, especially when the gas accumulates in confined spaces, such as manure pits (Hendry‐Hofer et al. 2020 ; Santana et al. 2021 ). H 2 S can cause eye and respiratory irritation in farm workers at concentrations of 10–100 ppm, whereas higher concentrations, such as those in manure pits, can cause asphyxiation and fatality (Park et al. 2016 ).
Language: English
Subfield: Process Chemistry and Technology
Field: Chemical Engineering
Domain: Physical Sciences
SDG: Zero hunger
Open Access status: gold
Estimated APC paid: $4,190
Awards: G1331539340, G3301798956
OpenAlex ID: W7124831552