Biotreatment of oily sludge and the involved microbial communities, particularly in saline environments, have been rarely investigated. We enriched a halophilic bacterial consortium (OS-100) from petroleum refining oily sludge, which degraded almost 86% of the aliphatic hydrocarbon (C10-C30) fraction of the oily sludge within 7 days in the presence of 100 g/L NaCl. Two halophilic hydrocarbon-degrading bacteria related to the genera Chromohalobacter and Halomonas were isolated from the OS-100 consortium. Hydrocarbon degradation by the OS-100 consortium was relatively higher compared to the isolated bacteria, indicating potential synergistic interactions among the OS-100 community members. Exclusion of FeCl2, MgCl2, CaCl2, trace elements, and vitamins from the culture medium did not significantly affect the hydrocarbon degradation efficiency of the OS-100 consortium. To the contrary, hydrocarbon biodegradation dropped from 94.1 to 54.4% and 5% when the OS-100 consortium was deprived from phosphate and nitrogen sources in the culture medium, respectively. Quantitative PCR revealed that alkB gene expression increased up to the 3rd day of incubation with 11.277-fold, consistent with the observed increments in hydrocarbon degradation. Illumina-MiSeq sequencing of 16 S rRNA gene fragments revealed that the OS-100 consortium was mainly composed of the genera Halomonas, Idiomarina, Alcanivorax and Chromohalobacter. This community structure changed depending on the culturing conditions. However, remarkable changes in the community structure were not always associated with remarkable shifts in the hydrocarbonoclastic activity and vice versa. The results show that probably synergistic interactions between community members and different subpopulations of the OS-100 consortium contributed to salinity tolerance and hydrocarbon degradation.

Wet meadows, a type of wetland, are vulnerable to climate change and human activity, impacting soil properties and microorganisms that are crucial to the ecosystem processes of wet meadows. To decipher the ecological mechanisms and processes involved in wet meadows, it is necessary to examine the bacterial communities associated with plant roots. To gain valuable insight into the microbial dynamics of alpine wet meadows, we used Illumina MiSeq sequencing to investigate how environmental factors shape the bacterial communities thriving in the rhizosphere and rhizoplane of three plant species: Cremanthodium ellisii, Caltha scaposa, and Cremanthodium lineare. The most abundant bacterial phyla in rhizosphere and rhizoplane were Proteobacteria > Firmicutes > Actinobacteria, while Macrococcus, Lactococcus, and Exiguobacterium were the most abundant bacterial genera between rhizosphere and rhizoplane. The mantel test, network, and structure equation models revealed that bacterial communities of rhizosphere were shaped by total nitrogen (TN), soil water content (SWC), soil organic carbon (SOC), microbial biomass carbon (MBC), microbial biomass nitrogen (MBN), pH, however, rhizoplane bacterial communities exhibited varying results. The bacterial communities exhibited significant heterogeneity, with stochastic process predominating in both the rhizosphere and rhizoplane. PICRUSt2 and FAPROTAX analysis revealed substantial differences in key biogeochemical cycles and metabolic functional predictions. It was concluded that root compartments significantly influenced the bacterial communities, although plant species and elevation asserted varying effects. This study portrays how physicochemical properties, plant species, and elevations can shift the overall structure and functional repertoire of bacterial communities in alpine wet meadows.

The present study aimed to investigate the molecular diversity of arbuscular mycorrhizal fungi (AMF) in natural seleniferous soils and their role in protecting plants from Se toxicity. The genomic DNA extracted from maize roots grown in seleniferous and non-seleniferous regions was amplified using AMF-specific primers by nested PCR. The 1.5 kb amplicon spanning pSSU-ITS-pLSU of 18S rRNA of AMF was deciphered using the Illumina Miseq Next Generation Sequencing (NGS) technique. A total of 17 AMF species from the seleniferous region and 18 AMF species from the non-seleniferous region were identified. The number of reads of Glomus irregularis, G. custos, and G. intraradices was higher in seleniferous soil than in non-seleniferous soil, indicating their tolerance to Se. A consortium of Se-tolerant AMF inoculum was prepared and inoculated to maize plants, grown in natural seleniferous soils. AMF-inoculated plants had healthy growth with higher root, shoot, and grain biomass than non-AMF-inoculated plants. AMF inoculation leads to higher Se accumulation in roots but lesser Se accumulation in shoots and seeds of inoculated maize plants as compared to control plants. Present study results suggest that AMF species from seleniferous soils have the potential to be used as biofertilizers to improve plant growth and tolerate Se toxicity in seleniferous soils.

Tepache is a native beverage from Mexico, which is usually elaborated with pineapple shells, brown cane sugar and is fermented naturally. Beneficial health effects have been attributed to its consumption; however, the total ecosystem of this beverage including chemicals (substrates for microbial growth, prebiotics, etc) and microbiota (probiotics), and potential functionality had not been studied. In this work, the analysis of the tepache beverage for its physicochemical characteristics, as well as its structure of microbial communities and the predictive metabolic functionalities was carried out. Chemical characterization was performed via enzymatic and GC-MS methods. The bacterial and fungal communities were identified by using 16S rRNA and ITS metabarcoding through Illumina MiSeq 2 × 300. The metabolic potential was predicted by in silico tools. This research showed that after 72 h of fermentation, the tepache physicochemical characteristics shifted to 9.5 Brix degrees and acidic pH. The content of ethanol, acetic and L-lactic acid increased significantly from 0.83 ± 0.02 to 3.39 ± 0.18 g/L, from 0.38 ± 0.04 to 0.54 ± 0.04 g/L and from 1.42 ± 0.75 to 8.77 ± 0.34 g/L, respectively. While, the total sugars was decreased from 123.43 ± 2.01 to 84.70 ± 2.34 g/L. The microbial diversity analysis showed a higher richness of bacterial communities and increased fungal evenness at the end of fermentation. At 72 h of fermentation the microbial community was dominated by Lactobacillus, Leuconostoc, Acetobacter and Lactococcus bacterial genera. As for the fungal community, Saccharomyces, Gibberella, Zygosaccharomyces, Candida, Meyerozyma, Talaromyces, Epicoccum and Kabatiella were found to be in most abundance. The predicted functionality profile evidenced a close-fitting relationship between fungal communities at 0 h with the bacterial communities at 72 h of fermentation. The metabolic potential showed that glycolysis and citrate cycle metabolism were predominant for fungal community, while glycolysis, fructose and tricarboxylic acid metabolism were more representative for the bacterial core. Tepache fermentation mainly occurred at two temporal successions. First, a lactic acid and ethanol fermentation dominated by lactic acid bacteria and yeast, and then an increase in acetogenic bacteria. This study revealed for the first time the physicochemical, microbiological changes and predictive functionality that are involved during tepache fermentation. These findings contributed to the knowledge of important microbial sources and could be essential to future efforts in manufacturing process. In addition, this work could help to analyze the health benefits that are empirically attributed to it by consumers.

Nonylphenol Ethoxylate (NPe) is a nonionic surfactant widely applied in domestic and industrial uses and its degradation generates the endocrine disruptor 4-Nonylphenol (4-NP). The effects of this compound in biological sewage treatment are uncertain, especially in anaerobic systems. The aim of this study was to assess the 4-NP removal and degradation in scale-up (20 L) Anaerobic Fluidized Bed Reactor (AFBR) filled with sand as support material, operated with Hydraulic Retention Time (HRT) of 18 h, fed with synthetic sewage plus 4-NP, performed in four phases named Phase I (894 mg COD L-1), Phase II (878 mg COD L-1, 127 μg 4-NP L-1), Phase III (940 mg COD L-1, 270 μg 4-NP L-1) and Phase IV (568 mg COD L-1, 376 μg 4-NP L-1). 4-NP did not affect reactor stability and organic matter removal remained stable at 94%. Highest 4-NP removal (78%) occurred for highest 4-NP influent (Phase IV), which resulted from biomass adaptation in the presence of ethanol. Through the 4-NP total mass balance, about 70% was biodegraded and 1% adsorbed on the sand bed. 4-NP addition promoted selection of microbial consortium strongly linked to aromatic compounds and surfactants degradation such as Geothrix, Holophaga, Aeromonas, Pelobacter, Pseudomonas, Delftia.

This research aimed to evaluate the impacts of Monascus purpureus on the microbial community and major metabolites of Cupei and vinegar of Sichuan bran vinegar (SBV). Cupei is the mixture of fermented materials and vinegar is the liquid leached from Cupei. The characteristics of microbial community were revealed by Illumina-MiSeq. The result suggested that inoculation of M. purpureus decreased the microbial diversities and inhibited several pathogens related microbes including Erwinia, Proteus and Ignatzschineria of Cupei. The dominant genera of SBV were Lactobacillus, Acetobacter, Trichoderma and Candida. With addition of M. purpureus, the total relative abundance of Lactobacillus and Acetobacter was increased from 75.14% to 99.79%. Furthermore, the major metabolites in corresponding vinegar were investigated by HPLC and HS-SPME-GC-MS. The result indicated that the addition of M. purpureus significantly promoted the accumulation of organic acids, aromatic esters and alcohols, whose contents were increased by 1.95, 2.30 and 3.55 times, respectively. Meanwhile acetic acid, lactic acid, phenethyl acetate and β-phenethyl alcohol were the dominant components in organic acids, esters and alcohols, respectively. In addition, the relationship between dominant microbes and major metabolites explored by redundancy analysis displayed that Lactobacillus, Acetobacter, Candida and Monascus were closely related with seven volatiles and five organic acids. This study provided an insight on regulation of microbial community and metabolic function of traditional fermented foods by bioaugmentation.

We report the 5.1 Mb noncontiguous draft genome of Afipia septicemium strain OHSU_II, isolated from blood of a female patient. The genome consists of 5,087,893 bp circular chromosome with no identifiable autonomous plasmid with a G + C content of 61.09% and contains 4898 protein-coding genes and 49 RNA genes including 3 rRNA genes and 46 tRNA genes.