Soil microbes’ response to sudden environmental changes is very complicated and has been lively debated. There are a handful of questions yet to answer: are there any succession rules for different soil microbial species to fit in the suddenly changed environment? And what is the correlation between the community succession and the habitat recovery? These questions remain unanswered yet. Nematode-trapping fungi (NTF) play a very important role in the soil ecosystem and can be studied by traditional culture method easily. So, in this study, the NTF community in two burned sites at two depths (0–10 and 10–20 cm) was investigated in comparison with adjacent unburned sites. While the original NTF community structure was rather different in the two unburned sites, the NTF community presented a consistent pattern in the two burned sites: (1) considerable amount of NTF in the shallow soil (0–10 cm) was killed by the extremely high temperature of fire and the vacant niches were subsequently replaced with NTF communities that were originally distributed in the deep soil (10–20 cm); (2) dominant species in the community changed from Arthrobotrys fungi which showed stronger saprophytic ability to Dactylellina fungi which showed stronger capturing ability; and (3) the vacant niche caused by the movement of Dactylellina fungi was taken by Drechslerella fungi. The study shows that microbes inhabited in the deep soil played a critical role in the after-fire process to recovery of the soil ecological system.

Chronic non-communicable diseases (CNCDs) pose a significant public health challenge. Addressing this issue, there has been a notable breakthrough in the prevention and mitigation of NCDs through the use of antioxidants and anti-inflammatory agents. In this study, we aim to explore the effectiveness of Eupatorium adenophora Spreng leaves (EASL) as an antioxidant and anti-inflammatory agent, and its potential applications. To construct a cellular model of oxidative damage and inflammation, Caco-2 cells were treated with tert-butyl hydroperoxide (t-BHP). The biocompatibility of EASL-AE with Caco-2 cells was assessed using the MTT assay, while compatibility was further verified by measuring LDH release and the protective effect against oxidative damage was also assessed using the MTT assay. Additionally, we measured intracellular oxidative stress indicators such as ROS and 8-OHdG, as well as inflammatory pathway signalling protein NFκB and inflammatory factors TNF-α and IL-1β using ELISA, to evaluate the antioxidant and anti-inflammatory capacity of EASL-AE. The scavenging capacity of EASL-AE against free radicals was determined through the DPPH Assay and ABTS Assay. Furthermore, we measured the total phenolic, total flavonoid, and total polysaccharide contents using common chemical methods. The chemical composition of EASL-AE was analyzed using the LC–MS/MS technique. Our findings demonstrate that EASL-AE is biocompatible with Caco-2 cells and non-toxic at experimental levels. Moreover, EASL-AE exhibits a significant protective effect on Caco-2 cells subjected to oxidative damage. The antioxidant effect of EASL-AE involves the scavenging of intracellular ROS, while its anti-inflammatory effect is achieved by down-regulation of the NFκB pathway. Which in turn reduces the release of inflammatory factors TNF-α and IL-1β. Through LC–MS/MS analysis, we identified 222 compounds in EASL-AE, among which gentianic acid, procaine and L-tyrosine were the compounds with high antioxidant capacity and may be the effective constituent for EASL-AE with antioxidant activity. These results suggest that EASL-AE is a natural and high-quality antioxidant and anti-inflammatory biomaterial that warrants further investigation. It holds great potential for applications in healthcare and other related fields.

Microplastics (MPs) are widely distributed and accumulated in the environment, making it nearly impossible for humans to avoid ingestion. Their toxicity can cause serious health damage and pose a threat to human health. In this context, developing strategies to prevent and restore toxic damage from their ingestion is extremely urgent. This study comprehensively employs various techniques, including metagenomics and metabolomics, to explore the pre-protective and restorative effects of Clostridium dalinum, a potential probiotic with excellent antioxidant and anti-inflammatory capabilities, on damage induced by exposure to polystyrene microplastics (PS-MPs) in mice. The results show that exposure to PS-MPs leads to significant intestinal damage in mice; preemptive intake of C. dalinum for pre-protection, or post-exposure intake of C. dalinum for restorative treatment, both significantly reduced the damage caused by MPs exposure, as evidenced by changes in intestinal length (PS-MPs exposure vs C. dalinum pre-protection vs C. dalinum restoration vs control = 36.55 vs 39.94 vs 40.12 vs 41.05 cm), barrier protein content (27.12 % vs 97.28 % vs 97.73 % vs 100.00 %), and inflammation levels (284.56 % vs 101.05 % vs 98.17 % vs 100.00 %). Mechanistically, the pre-protective and restorative effects of C. dalinum both rely on upregulating the expression of barrier proteins such as ZO-1 and Occludin and inhibiting the TLR4/NF-κB inflammatory signaling pathway. Meanwhile, the two intervention modes also exhibit specific mechanisms: in the pre-protection mode, C. dalinum enhances lipid metabolic balance and antioxidant reserves by pre-activating the PPARγ/GPR43 pathway, and enriches the ABC transporters pathway to promote toxin efflux capacity, thereby preventing PS-MPs-induced damage; in the restoration mode, C. dalinum repairs intestinal damage by enriching the beneficial bacterium Lachnospiraceae NK4A136 and inhibiting the pro-inflammatory bacterium Desulfovibrio, and regulating intestinal metabolites. In summary, this study is the first to confirm that C. dalinum can effectively prevent and restore intestinal damage caused by PS-MPs exposure through the synergistic pathway of "microbiota-metabolism-barrier". Importantly, this study is the first to reveal the potential and unique mechanisms of probiotics in preventing and restoring MPs exposure toxicity, providing a theoretical basis for the future development of probiotic-based defense strategies.

Background: The post-fire recovery of soil microbes is critical for ecological conservation, yet the mechanisms behind it are not well understood. Aim: In this study, we examined the recovery patterns of culturable soil microbes following a fire. Methods: A field experiment was conducted in which a forest soil was subjected to surface fire, and the culturable microbial biomass and soil physicochemical characteristics were evaluated 1 day after the fire, and subsequently every 10 days for 90 days. Key results: Microbial biomass significantly reduced post-fire, with varying effects across microbial taxa and soil layers. The recovery patterns of microbial biomass at topsoil (0–10 cm) and subsoil (10–20 cm), and among different microbial taxa were also different and were determined by the residual microbiomes. Heat released during a fire (the combination of heat duration and temperature reached during treatment) was significantly related to the decrease and recovery of microbial biomass, whereas there was no relationship between soil physicochemical properties and microbial biomass recovery. Conclusions: Soil microbial biomass recovered quickly post-fire, which can be mainly due to the rapid attenuation of heat along the soil profile. Heat released during fire was the key factor determining the residual biomass, and the residual microbiomes determined the recovery patterns of the various taxa that comprise the culturable microbial biomass. Implications: Due to the complexity of natural fire, simulated fire experiment and systematic sampling based on space (soil profile) and time are crucial to investigate the dynamics of soil microbes post-fire.

Heat input and ash residues are main components of vegetation fire disturbances. Understanding the distinct impacts of heat and ash on soil microorganisms is crucial to comprehend and predict the induced changes in soil ecosystem composition and dynamics following different types of fire disturbances. This study’s main goal was to track the dynamic shifts in the community of soil nematode-trapping fungi (NTF) following the separate disturbances of heat and ash by means of a specifically designed experiment conducted in the field. Four simulated fire treatments, one treatment reproducing natural burning, and one control treatment were taken into account. Every ten days following the disturbance, soil samples from each treatment were collected, and soil NTF and physicochemical characteristics were measured. The results showed that: (1) Heat drastically decreased the number of strains and heavily altered the NTF community, but it also encouraged the emergence of new NTF species. Instead, no overt changes were observed in the treatment that just experienced the addition of ash on the soil. (2) When compared to treatments that received only heat input, the lower strain count of NTF recovered more quickly in the natural burning treatment which was affected by both heat and ash input. These findings suggest that the disruptive effect of fire heat on soil NTF biomass may be counterbalanced by the emergence of new species and the repairing capabilities of new nutrients introduced by ash residue. In the future, both conventional and cutting-edge techniques should be considered in research designs to better understand the ecological role of fire disturbances occurring at different intensities, as well as the mechanisms that make soil ecosystems resilient to fire, in particular the role of new species.

Oxidative damage, oxidative inflammation, and a range of downstream diseases represent significant threats to human health. The application of natural antioxidants and anti-inflammatory agents can help prevent and mitigate these associated diseases. In this study, we aimed to investigate the effectiveness of walnut green husk (WNGH) as an antioxidant and anti-inflammatory agent in an in vitro setting. HepG2 cells were treated with tert-butyl hydroperoxide (t-BHP) to establish a cellular model of oxidative damage and inflammation. We assessed the biocompatibility of walnut green husk aqueous extract (WNGH-AE) on HepG2 cells using MTT and LDH assays (WNGH-AE concentration: 0.05, 0.1, 0.2, 0.4, 0.8, 1.6, 3.2, 6.4, and 12.8 mg/mL). Additionally, we measured intracellular oxidative stress indicators, such as ROS and 8-OHdG, along with inflammatory factors TNF-α and IL-1β through ELISA to evaluate the antioxidant and anti-inflammatory capacity of WNGH-AE (concentration: 0.025, 0.05, 0.1 mg/mL) in HepG2 cells. We also determined the free radical scavenging capacity of various extracts of WNGH using DPPH and ·OH methods. The total phenols, total polysaccharides, and total flavonoids in WNGH-AE were analyzed using the Folin-Ciocalteu’s reagent, the phenol-sulfuric acid method, and the spectrophotometry, respectively. The bioactive components of WNGH-AE were analyzed using LC-MS/MS. Our results demonstrated that WNGH-AE was highly biocompatible with HepG2 cells. The antioxidant effect of WNGH-AE involved the scavenging of intracellular ROS, while its anti-inflammatory effect was linked to the down-regulation of the NF-κB pathway. Compared to other extractants (ethyl acetate, n-butanol, 75% ethanol, and petroleum ether), WNGH-AE exhibited the strongest free radical scavenging ability. Through LC-MS/MS analysis, we identified 403 compounds in WNGH-AE, with gentisic acid being the most abundant and possessing high antioxidant capacity, suggesting it may be a key active component contributing to the antioxidant activity of WNGH-AE. In conclusion, our findings indicate that WNGH-AE is a natural, high-quality antioxidant and anti-inflammatory biomaterial deserving further research and development, with significant potential applications in healthcare. (311 words)