We investigated the potential of Mucuna pruriens and Canavalia ensiformis as phytoremediation candidates for Tebuthiuron (TBT)-contaminated soils. Crotalaria juncea was the bioindicator specie for tebuthiuron and Lactuca sativa used in ecotoxicological bioassays, both analyses aim to verify the herbicide presence in soil samples as TBT is persistent with environmental and health risks due to its tendency to bioaccumulate. We conducted a 140-day greenhouse experiment associated with bioaugmentation by microbial inoculants - solid or liquid. Both C. ensiformis (CE) and M. pruriens (MP) exhibited distinct growth patterns, with MP demonstrating a faster growth rate than CE, evident from its higher growth apex (α = 84.52) and specific growth rate (k = 0.113). While soil samples with microbial inoculants demonstrated significant biomass increase with tebuthiuron absence, the introduction this herbicide notably hindered phytomass production, particularly in MP + TBT treatments. Liquid inoculant notably contributed to biomass accumulation in MP, whereas microbial bioaugmentation did not substantially enhance phytomass in CE under tebuthiuron presence. Furthermore, C. juncea exhibited initially slow development in the reference treatment but displayed accelerated growth and greater height with liquid inoculant compared to solid inoculant. Despite the presence of tebuthiuron, C. juncea in soil with TBT alone reached a maximum height exceeding 100 cm. However, tebuthiuron significantly reduced biomass accumulation in C. juncea, indicating its high sensitivity to this herbicide. Liquid inoculant facilitated the highest dry biomass accumulation in C. juncea, yet the introduction of tebuthiuron led to a considerable reduction in biomass, underscoring the plant's susceptibility to it. While bioaugmentation showed potential in mitigating herbicide phytotoxicity, its efficacy varied among tested inoculants. In bioassays with L. sativa, bioaugmentation with liquid inoculant resulted in a higher final germination index (GI) compared to solid inoculant and the reference treatment. Conversely, soil samples containing only tebuthiuron demonstrated a higher final GI and growth velocity compared to the reference treatment, implying the natural attenuation of toxicity over time. Additionally, previous cultivation of Mucuna pruriens positively influenced the development of test-organism, resulting in a higher GI and growth rate compared to the reference treatment. These findings provide valuable insights for various stakeholders, including the scientific community, industries, and bioengineers. They offer a strong incentive to develop advanced bioremediation strategies to address persistent pesticide contamination, especially in intensive agroecosystems like sugarcane-producing fields. Implementing our biological solution holds the potential to usher in a cleaner and safer era in agriculture, thereby protecting both society and the environment.

The immobilisation of bacteria on biochar has shown potential for enhanced remediation of petroleum hydrocarbon-contaminated soil. However, there is a lack of knowledge on the effect of bacterial immobilisation on biosolids-derived biochar for the remediation of diesel-contaminated soil. The aim of this current study was to assess the impact of the immobilisation on biosolids-derived biochar of an autochthonous hydrocarbonoclastic bacteria, Ochrobacterium sp. (BIB) on the remediation of diesel-contaminated soil using a laboratory based mesocosm study. Additionally, the effect of fertiliser application on the efficacy of the BIB treatment was investigated. Biochar (BC) application alone led to significantly higher hydrocarbon removal compared to the control treatment at all sampling times (4,887 – 11,589 mg/kg higher). When Ochrobacterium sp. was immobilised on biochar (BIB), the hydrocarbon removal was higher than BC by 5,533 mg/kg and 1,607 mg/kg at weeks 10 and 22, respectively. However, when BIB was co-applied with fertiliser (BIBF), the hydrocarbon removal was lower than BIB by 6,987 – 11,767 mg/kg. Quantitative PCR analysis revealed that the gene related to Ochrobacterium sp. was higher in BIB than in the BC treatment, which likely contributed to higher hydrocarbon removal in the BIB treatment. The findings of this study demonstrate that bacteria immobilisation on biosolids-derived biochar is a promising technique for the remediation of diesel-contaminated soil. Future studies should focus on optimising the immobilisation process for enhanced hydrocarbon removal.

In order to explore the effect of Wickerhamomyces on the production of flavor compounds in Xiaoqu Baijiu, this study examined the correlation between the fungal communities in Xiaoqu and ester compounds. It was hypothesized that Wickerhamomyces contributes to the aroma of Xiaoqu. Enhanced fermentation methods were used to validate the role of Wickerhamomyces in Xiaoqu Baijiu brewing. Compared to traditional Xiaoqu, enhanced fermentation significantly increased the acidity of fermented grains and starch utilization rate (P<0.05). The fungal communities in fermented grains were analyzed by high-throughput sequencing technology. The dominant fungi in both control and test groups were Saccharomyces, Cyberlindnera, Rhizopus, and Meyerozyma, with Wickerhamomyces replacing Saccharomymycopsis in the enhanced group. Flavor compounds in the fermentation experiments were analyzed, revealing that ethyl acetate content in Xiaoqu Baijiu increased by 949.94 mg/L in the test group, while isoamyl alcohol decreased by 23.62 mg/L and isobutanol decreased by 34.81 mg/L. Functional prediction analysis using PICRUSt2 confirmed a higher relative abundance of enzymes involved in ethyl acetate metabolism and a lower relative abundance of enzymes involved in higher alcohol metabolism in the test group. These findings demonstrate that Wickerhamomyces enhances ethyl acetate production and reduces higher alcohols during Xiaoqu Baijiu brewing, offering a theoretical foundation for enhancing the quality of Xiaoqu Baijiu.

Polycyclic aromatic hydrocarbons (PAHs), which consist of low-molecular-weight PAHs (LMW-PAHs) and high-molecular-weight PAHs (HMW-PAHs), form an important class of pollutants. Pyrene and benzo[a]pyrene (BaP) are the main pollutants belonging to HMW-PAHs, and their degradation by microorganisms remains an important strategy for their removal from the environments. Extensive studies have been carried out on the isolation and characterisation of microorganisms that actively degrade LMW-PAHs, and to a certain extent, the HMW-PAH pyrene. However, so far, limited work has been carried out on BaP biodegradation. BaP consists of five fused aromatic rings, which confers this compound a high stability, rendering it less amenable to biodegradation. The current review summarizes the emerging reports on BaP biodegradation. More specifically, work carried out on BaP bacterial degradation and current knowledge gaps that limit our understanding of BaP degradation are highlighted. Moreover, new avenues of research on BaP degradation are proposed, specifically in the context of the development of “omics” approaches