Community Analysis Research Articles

Distribution and functional perspective analysis of epiphytic and endophytic bacterial communities associated with marine seaweeds, Alexandria shores, Egypt

There is an enormous diversity of life forms present in the extremely intricate marine environment. The growth and development of seaweeds in this particular environment are controlled by the bacteria that settle on their surfaces and generate a diverse range of inorganic and organic chemicals. The purpose of this work was to identify epiphytic and endophytic bacterial populations associated with ten common marine macroalgae from various areas along the Mediterranean Sea coast in Alexandria. This was done to target their distribution and possible functional aspects. Examine the effects of the algal habitat on the counting and phenotypic characterization of bacteria, which involves grouping bacteria based on characteristics such as shape, colour, mucoid nature, type of Gram stain, and their ability to generate spores. Furthermore, studying the physiological traits of the isolates under exploration provides insight into the optimum environmental circumstances for bacteria associated with the formation of algae. The majority of the bacterial isolates exhibited a wide range of enzyme activities, with cellulase, alginase, and caseinase being the most prevalent, according to the data. Nevertheless, 26% of the isolates displayed amylolytic activity, while certain isolates from Miami, Eastern Harbor, and Montaza lacked catalase activity. Geographical variations with the addition of algal extract may impact on the enumeration of the bacterial population, and this might have a relationship with host phylogeny. The most significant observation was that endophytic bacteria associated with green algae increased in all sites, while those associated with red algae increased in Abu Qir and Miami sites and decreased in Eastern Harbor. At the species level, the addition of algal extract led to a ninefold increase in the estimated number of epiphytic bacteria for Cladophora pellucida in Montaza. Notably, after adding algal extract, the number of presented endophytic bacteria associated with Codium sp. increased in Abu Qir while decreasing with the same species in Montaza. In addition to having the most different varieties of algae, Abu Qir has the most different bacterial isolates.

Analysis of microbial communities in wheat, alfalfa, and oat crops after Tilletia laevis Kühn infection.

Common bunt caused by Tilletia laevis Kühn is one of the most serious fungal diseases of wheat. The root-microbial associations play key roles in protecting plants against biotic and abiotic factors. Managing these associations offers a platform for improving the sustainability and efficiency of agriculture production. Here, by using high throughput sequencing, we aimed to identify the bacterial and fungal associations in wheat, alfalfa, and oat crops cultivated in different years in the Gansu province of China. Soil samples (0-6 cm below the surface) from infected wheat by T. laevis had significantly more bacterial and fungal richness than control samples as per the Chao1 analysis. We found some dominant fungi and bacterial phyla in infected wheat by T. laevis, such as Proteobacteria, Acidobacteria, Actinobacteria, Chloroflexi, Ascomycota, Basidiomycota, and Mortierello mycota. We also analyzed the chemical and enzymatic properties of soil samples after T. laevis inoculation. The total nitrogen, total kalium (TK), ammonium nitrogen, available kalium, organic carbon, invertase, phosphatase, and catalase were more in T. laevis-infected samples as compared to the control samples, while pH, total phosphorus, nitrate nitrogen, available phosphorus, and urease were more in control samples compared to T. laevis-infected samples. The results of this study will contribute to the control of wheat common bunt by candidate antagonistic microorganisms and adverse properties of soil.

Plastisphere Microbiomes Respiring Persistent Organohalide Pollutants.

Plastics are invading nearly all ecosystems on earth, acting as emerging repositories for toxic organic pollutants and thereby imposing substantial threats to ecological integrity. The colonization of plastics by microorganisms, forming the plastisphere, has garnered attention due to its potential influence on biogeochemical cycles. However, the capability of plastisphere microorganisms to attenuate organohalide pollutants remains to be evaluated. This study revealed that the plastisphere, collected from coastal ecosystems, harbors unique microbiomes, while the natural accumulation of organohalide pollutants on plastics may favor the proliferation of organohalide-respiring bacteria (OHRB). Laboratory tests further elucidated the high potential of plastisphere microbiota to reductively dehalogenate a variety of organohalide pollutants. Notably, over 70% tested plastisphere completely debrominated tetrabromobisphenol A (TBBPA) and polybrominated diphenyl ethers (PBDEs) to nonhalogenated products, whereas polychlorinated biphenyls (PCBs) were converted to lower congeners under anaerobic conditions. Dehalococcoides, Dehalogenimonas, and novel Dehalococcoidia populations might contribute to the observed dehalogenation based on their growth during incubation and positive correlations with the quantity of halogens removed. Intriguingly, large fractions of these OHRB populations were identified in a lack of the currently known TBBPA/PBDEs/PCBs reductive dehalogenase (RDase) genes, suggesting the presence of novel RDase genes. Microbial community analyses identified organohalides as a crucial factor in determining the composition, diversity, interaction, and assembly of microbes derived from the plastisphere. Collectively, this study underscores the overlooked roles of the plastisphere in the natural attenuation of persistent organohalide pollutants and sheds light on the unignorable impacts of organohalide compounds on the microbial ecology of the plastisphere.

Polystyrene microplastics aggravate radiation-induced intestinal injury in mice

Radiotherapy is a common treatment for abdominal and pelvic tumors, while the radiation-induced intestinal injury (RIII) is one of the major side-effects of radiotherapy, which reduces the life quality and impedes the treatment completion of cancer patients. Previous studies have demonstrated that environmental pollutant microplastics led to various kinds of injury in the gut, but its effects on RIII are still uncovered. In this study, we fed the C57BL/6J mice with distilled water or 50 μg/d polystyrene microplastics (PSMPs) for 17 days and exposed the mice to total abdominal irradiation (TAI) at day 14. Then the severity of RIII was examined by performing histopathological analysis and microbial community analysis. The results demonstrated that PSMPs significantly aggravated RIII in small intestine rather than colon of mice upon TAI. PSMPs increased levels of the histopathological damage and the microbial community disturbance in mice small intestine, shown by the overabundance of Akkermansiaceae and the decrease of microflora including Lactobacillaceae, Muribaculaceae and Bifidobacteriaceae. In conclusion, our results suggested that more microplastics exposure might led to more severe RIII, which should be considered in patients’ daily diet adjustment and clinical radiotherapy plan evaluation. Furthermore, this study also called for the further researches to uncover the underlying mechanism and develop novel strategies to attenuate RIII in mice intestine.

MOSCA 2.0: A bioinformatics framework for metagenomics, metatranscriptomics and metaproteomics data analysis and visualization.

The analysis of meta-omics data requires the utilization of several bioinformatics tools and proficiency in informatics. The integration of multiple meta-omics data is even more challenging, and the outputs of existing bioinformatics solutions are not always easy to interpret. Here, we present a meta-omics bioinformatics pipeline, Meta-Omics Software for Community Analysis (MOSCA), which aims to overcome these limitations. MOSCA was initially developed for analysing metagenomics (MG) and metatranscriptomics (MT) data. Now, it also performs MG and metaproteomics (MP) integrated analysis, and MG/MT analysis was upgraded with an additional iterative binning step, metabolic pathways mapping, and several improvements regarding functional annotation and data visualization. MOSCA handles raw sequencing data and mass spectra and performs pre-processing, assembly, annotation, binning and differential gene/protein expression analysis. MOSCA shows taxonomic and functional analysis in large tables, performs metabolic pathways mapping, generates Krona plots and shows gene/protein expression results in heatmaps, improving omics data visualization. MOSCA is easily run from a single command while also providing a web interface (MOSGUITO). Relevant features include an extensive set of customization options, allowing tailored analyses to suit specific research objectives, and the ability to restart the pipeline from intermediary checkpoints using alternative configurations. Two case studies showcased MOSCA results, giving a complete view of the anaerobic microbial communities from anaerobic digesters and insights on the role of specific microorganisms. MOSCA represents a pivotal advancement in meta-omics research, offering an intuitive, comprehensive, and versatile solution for researchers seeking to unravel the intricate tapestry of microbial communities.

Effect of cyanobacteria biochar addition on humification, fungal dynamics and its mechanism of action in pig manure composting

Aerobic composting is an effective method for resourceful treatment of pig manure (PM). However, traditional composting often suffers from low humification effect and inactive fungal communities. In order to better treat PM, this study applied different doses of cyanobacterial biochar (CB) (T1:0 %; T2:2.5 %; T3:5 %; T4:7.5 %; T5:10 %; and T6:20 %) to PM composting and investigated the effects of biochar additives on the humification of PM composting and fungal communities. The results showed that biochar addition could prolong the thermophilic period (>50°C) by 1–4 days, with T4 being the most effective. Humification analysis showed that biochar increased the degradation of fulvic acid by 4.95–11.19 % and increased the formation of humic acid by 3.43–9.44 %, and final HA/FA ratio of T5 being the highest (2.44) compared to other treatments. The fungal abundance also confirmed that the addition of biochar significantly decreased the number of Ascomycetes at the maturation stage by 15.23 ∼ 89.23 % and increased the number of Basidiomycetes by 7.39 ∼ 119.54 times. Fungal community analysis showed that biochar could promote the birth of dominant fungi in the thermophilic phase and T5 had greater abundance of fungi than the other treatment groups. Network analysis indicated that high doses of CB (10–20 %) could enhance positive interactions among fungi to a greater extent. In conclusion, 10 % CB (T5) can optimize the compost quality to the greatest extent and has the highest application value.

NZVI@BC as a Soil Amendment and Its Effects on Potted Rice Growth and Soil Properties

This study investigated the effects of nano zero-valent iron-modified biochar (nZVI@BC) as a soil amendment on potted rice growth, soil properties, and heavy metal dynamics. Seven treatments with varying amounts of soil conditioner, biochar, and nZVI@BC were applied to potted rice. Results showed that nZVI@BC application significantly improved rice agronomic traits, with the 15 g·kg−1 treatment increasing the panicle formation rate by 15% and 100-grain weight by 8% compared to the control. Soil fertility was enhanced, with available phosphorus increasing from 137 to 281 mg·kg−1 in the most effective treatment. Heavy metal analysis revealed that nZVI@BC application did not increase soil heavy metal content, with Cd levels remaining below 0.3 mg·kg−1 across treatments. Notably, the 10 g·kg−1 nZVI@BC treatment showed potential for slight Cd immobilization, reducing its concentration from 0.32 to 0.26 mg·kg−1. Microbial community analysis showed that nZVI@BC altered soil microbial diversity and composition, with the 10 g·kg−1 treatment resulting in the highest fungal diversity (Chao1 index: 294.219). The relative abundance of the beneficial fungal class Agaricomycetes increased from 40% to 55% with optimal nZVI@BC application. These findings suggest that nZVI@BC has potential as an effective soil amendment for improving rice cultivation while maintaining soil health, microbial diversity, and potentially mitigating heavy metal contamination.

Integrated analysis of intestinal microbial community and muscle transcriptome profile in rabbits

Intestinal microbial community plays an important part in maintaining health and skeletal muscle development in livestock. This study is the first of its kind in the world. In order to better understand the relationship between gut microbiota and gene expression in skeletal muscle of rabbits, caecum contents and longissimus dorsi tissues of rabbits at 0 d (S1), 35 d (S2) and 70d (S3) were collected and subjected for 16S rRNA sequencing and transcriptome sequencing. Our results showed that, among three groups of rabbits, Firmicutes and Bacteroidetes were the dominant phyla at the phylum level, while Akmansia, Bacteroides and Ruminobacter were the dominant genera at the genus level, and the relative abundance of Akmansia and Bacteroides increased firstly and then decreased from 0 d to 70 d. By analyzing the transcriptome sequencing data, we identified 2866, 2446 and 4541 differentially expressed genes (DEGs) in S1 vs S2, S2 vs S3 and S1 vs S3 groups, respectively. Finally, we performed correlation analysis between gut microbiota and the expression levels of muscle development-related genes of rabbits at 0 d and 70 d. Compared with 0 day old rabbits, in 70 day old rabbits Acinetobacter and Cronbacter with decreased abundance, and Ruminococcaceae_UCG-014 and Ruminococcus_1 with increase abundance is beneficial to caecum health in rabbits. These results will lay a foundation for further re-searches about the relationship between caecum microflora and muscle development in rabbits.

Exploring the Influence of Date Palm Cultivars on Soil Microbiota

Plants thrive in diverse environments, where root-microbe interactions play a pivotal role. Date palm (Phoenix dactylifera L.), with its genetic diversity and resilience, is an ideal model for studying microbial adaptation to different genotypes and stresses. This study aimed to analyze the bacterial and fungal communities associated with traditional date palm cultivars and the widely cultivated “Deglet Nour” were explored using metabarcoding approaches. The microbial diversity analysis identified a rich community with 13,189 bacterial and 6442 fungal Amplicon Sequence Variants (ASVs). Actinobacteriota, Proteobacteria, and Bacteroidota dominated bacterial communities, while Ascomycota dominated fungal communities. Analysis of the microbial community revealed the emergence of two distinct clusters correlating with specific date palm cultivars, but fungal communities showed higher sensitivity to date palm genotype variations compared to bacterial communities. The commercial cultivar “Deglet Nour” exhibited a unique microbial composition enriched in pathogenic fungal taxa, which was correlated with its genetic distance. Overall, our study contributes to understanding the complex interactions between date palm genotypes and soil microbiota, highlighting the genotype role in microbial community structure, particularly among fungi. These findings suggest correlations between date palm genotype, stress tolerance, and microbial assembly, with implications for plant health and resilience. Further research is needed to elucidate genotype-specific microbial interactions and their role in enhancing plant resilience to environmental stresses.

Deoxygenation of the Eastern Tropical North Pacific over the last 1200 years

Oxygen minimum zones (OMZ) are characterized by a dissolved oxygen (DO) concentration <0.5 ml L−1. In situ DO measurements suggest that the global OMZ upper limit is shallower than 60 years ago due to global warming. The benthic foraminifera assemblage, trace elements, and biological productivity and denitrification tracers have been used in paleoceanographic research, given that they indicate dysoxic and suboxic changing conditions of bottom water. Studies of benthic foraminifera assemblages in the southwestern margin of Baja California Sur are scarce. Thus, it is necessary to conduct a paleoecological analysis of the benthic foraminifera community on an approximately 1200-year timeline. The sediment core LONO09-MC02 (1200 years old) collected at 680 m depth was examined to analyze benthic foraminifera relative abundances and estimate the DO concentration in the OMZ of Baja California Sur's southwestern margin. The DO concentrations inferred from benthic foraminifera assemblages ranged between 0.09- and 0.17-ml l−1 (4.4 and 8.0 μM). This suggests that the OMZ has maintained dysoxic conditions over the past 1200 years. Moreover, the cluster and principal component analysis defined dysoxic, suboxic, and oxic assemblages. The decoupling between geochemical tracers was associated with biogeochemical cycles of the North Pacific subtropical gyre and varied in response to intermediate water circulation in the Pacific Ocean. The low estimate of dissolved oxygen concentration corresponded with minimal solar activity, favoring La Niña-like oceanographic conditions with high primary productivity.

Deciphering the ecological impact of azo dye pollution through microbial community analysis in water-sediment microcosms.

The uncontrolled release of untreated dyeing wastewater into aquatic ecosystems poses global environmental risks. It alters native microbial communities and associated ecological processes, often going unnoticed. Therefore, the influence of acid orange 7dye (AO7) contamination on the natural microbial community was investigated using a water-sediment microcosm. Compared to sterile microcosms, complete dye decolourization in natural microcosms showed microbial communities' significance in combating xenobiotic contamination. Proteobacteria dominated the water community, whereas Firmicutes dominated the sediment. AO7 exposure induced notable shifts in the structural composition of the bacterial community in both water and sediment. Niveispirillum exhibited a marked decrease, and Pseudomonas demonstrated a notable increase. The - 9.0 log2FC in Niveispirillum, a nitrogen-fixing bacterium, from 24.4% in the control to 0.1% post-treatment, may disrupt nutrient balance, plant growth, and ecosystem productivity. Conversely, elevated levels of Pseudomonas sp. resulting from azo dye exposure demonstrate its ability to tolerate and bioremediate organic pollutants, highlighting its resilience. Functional profiling via KEGG pathway analysis revealed differential expression patterns under AO7 stress. Specifically, valine, leucine, and isoleucine degradation pathways in water decreased by 52.2%, and cysteine and methionine metabolism ceased expression entirely, indicating reduced protein metabolism and nutrient bioavailability under dye exposure. Furthermore, in sediment, glutathione metabolism ceased, indicating increased oxidative stress following AO7 infusion. However, C5-branched dibasic acid metabolism and limonene and pinene degradation were uniquely expressed in sediment. Decreased methane metabolism exacerbates the effects of global warming on aquatic ecosystems. Further, ceased-butanoate metabolic pathways reflect the textile dye wastewater-induced adverse impact on ecological processes, such as organic matter decomposition, energy flow, nutrient cycling, and community dynamics that help maintain self-purification and ecological balance in river ecosystems. These findings underscore the critical need for more comprehensive environmental monitoring and management strategies to mitigate ecological risks posed by textile dyes in aquatic ecosystems, which remain unnoticed.

Enhancement of biohythane production from palm oil mill effluent by Thermoanaerobacterium thermosaccharolyticum PSU-2 and methanogenic mixed cultures using a thermophilic two-ring bioreactor

A novel thermophilic two-ring bioreactor was employed to produce biohythane from palm oil mill effluent (POME) using Thermoanaerobacterium thermosaccharolyticum PSU-2 and thermophilic methanogenic mixed cultures. The reactor system demonstrated impressive performance, achieving hydrogen and methane yields of 113.3 ± 15.0 mL/g-VS and 473.0 ± 60.0 mL/g-VS, respectively, with a total biohythane composition of 4.3 % H2, 37.1 % CO2, and 58.6 % CH4. The process exhibited high treatment efficiency, with COD and VS removal efficiencies reaching 93.7 % and 84.3 %, respectively. Microbial community analysis revealed the crucial roles of various microorganisms in the biohythane production process. Thermoclostridium sp., Thermoanaerobacterium sp., and Anaerobranca sp. were identified as key players in hydrogen production, while Bacteroides sp. and Methanobacterium sp. were found to be essential for methane production. The optimization of operating conditions, including pH (5.0–8.0), temperature (55 °C), and hydraulic retention time (2 d for H2 and 10 d for CH4), significantly enhanced biohythane production efficiency. The techno-economic analysis demonstrated the economic viability of the thermophilic two-ring bioreactor system, with a net present value of 4,186,000 USD, an internal rate of return of 82 %, and a payback period of 1.4 years. These findings highlight the potential of this innovative technology as a sustainable and economically attractive solution for treating POME and simultaneously producing renewable energy in the form of biohythane, contributing to the sustainable development of the palm oil industry and the mitigation of greenhouse gas emissions.

Fe oxides nano-modified pumice enhances hydrogenotrophic methanogenesis in anaerobic digestion: Performance and mechanism of microbial community

Anaerobic digestion (AD), as an eco-friendly biological process, shows potential for the decomposition of leachate produced by waste incineration power plants. In this study, the effects of Fe oxides nano-modified pumice (FNP) were investigated on the fresh leachate AD process. Firstly, a simple hydrothermal method was used to prepare FNP, then introduced into the UASB reactor to evaluate its AD efficiency. Results showed that the inclusion of FNP could shorten the lag phase by 10 days compared to the control group. Furthermore, cumulative methane production in the FNP group was enhanced by 20.11%. Mechanistic studies suggested that hydrogenotrophic methanogenesis in the FNP group was more pronounced due to the influence of key enzymes (i.e., dehydrogenase and coenzyme F420). Microbial community analysis demonstrated that FNP could enhance the abundance of Methanosarcina, Proteobacteria, Sytrophomonas, and Limnobacter, which might elevate enzyme activity involved in methane production. These findings suggest that FNP might mediate interspecies electron transfer among these microorganisms, which is essential for efficient leachate treatment.

Analysis of Community and Stakeholder Relationships in the Development of Cigadung Creative Tourism Urban Village

This study examines local communities and stakeholders in the establishment of Cigadung Creative Tourism Urban Village in Bandung City. The success of Cigadung Creative Tourism Urban Village depends on effective cooperation between the local population, government, and tourism sector. This study uses qualitative descriptive research method included observation, interviews, and document analysis. The results demonstrated that local communities, especially Pokdarwis, are essential to tourism planning, management, and destination marketing. Government assistance and partnership with academics and businesses have helped this tourism urban community succeed. However, party coordination issues must be resolved by open communication and collaboration. This research sheds light on sustainable tourism development dynamics that can be used to benefit local welfare and culture.

Exploring Shared Challenges of Empowered Patients and Entrepreneurs: Towards Diversity, Innovation, and Entrepreneurship in Post-Crisis Contexts

This practical study explores the shared challenges faced by individuals managing chronic health conditions and entrepreneurs within the context of post-crisis periods, focusing on diversity, innovation, and individual empowerment. The aim is to develop a theoretical framework elucidating the mechanisms behind these challenges and their implications for fostering diversity, social innovation, and sustainability. Methodologically, an integrative approach was employed, drawing upon insights from psychology, sociology, health management, and entrepreneurship literature to conduct a comprehensive analysis. The research utilized mixed methods, including scoping reviews and qualitative analysis of virtual communities, to uncover the dynamic mechanisms that drive empowerment. This approach not only validated the theoretical framework but also proposed practical strategies to harness diversity, innovation, and entrepreneurship in post-crisis contexts. Drawing upon Dubin’s methodology, the study structured the theoretical framework to highlight the interconnectedness of empowerment experiences within communities. The findings underscore the interconnectedness of empowerment experiences within communities and highlight the vital role of collaborative environments and support networks in promoting diversity, innovation, and entrepreneurship. Ultimately, this research contributes to the development of strategies that capitalize on cultural diversities and reap the benefits of different nationalities, knowledge areas, and cultures, particularly in the aftermath of crises.

Seasonal and interannual variability of the free-living and particle-associated bacteria of a coastal microbiome.

Marine microbial communities differ genetically, metabolically, and ecologically according to their lifestyle, and they may respond differently to environmental changes. In this study, we investigated the seasonal dynamics of bacterial assemblies in the free-living (FL) and particle-associated (PA) fractions across a span of 6 years in the Blanes Bay Microbial Observatory in the Northwestern Mediterranean. Both lifestyles showed marked seasonality. The trends in alpha diversity were similar, with lower values in spring-summer than in autumn-winter. Samples from both fractions were grouped seasonally and the percentage of community variability explained by the measured environmental variables was comparable (32% in FL and 31% in PA). Canonical analyses showed that biotic interactions were determinants of bacterioplankton dynamics and that their relevance varies depending on lifestyles. Time-decay curves confirmed a high degree of predictability in both fractions. Yet, 'seasonal' Amplicon Sequence Variants (ASVs) (as defined by Lomb Scargle time series analysis) in the PA communities represented 46% of the total relative abundance while these accounted for 30% in the FL fraction. These results demonstrate that bacteria inhabiting both fractions exhibit marked seasonality, highlighting the importance of accounting for both lifestyles to fully comprehend the dynamics of marine prokaryotic communities.

Fuzi lizhong pills alter microbial community compositions and metabolite profiles in ulcerative colitis rat with spleen-kidney yang deficiency syndrome

Ethnopharmacological relevanceUlcerative colitis (UC) is a chronic inflammatory bowel condition that is frequently related with Spleen-Kidney Yang Deficiency Syndrome (SKYD) in Chinese medicine. Fuzi Lizhong Pill (FLZP), a traditional medicine for SKYD, has been utilized in China for generations, although the exact mechanism by which it treats UC is unknown. Aim of the studyThe goal of this study is to further understand FLZP's therapeutic mechanism in SKYD-associated UC. Materials and methodsTo investigate the impact of FLZP on SKYD-associated UC, we used a comprehensive method that included serum metabolomics and gut microbiota profiling. The chemical composition of FLZP was determined using mass spectrometry. UC rats with SKYD were induced and treated with FLZP. Serum metabolomics and 16S rRNA microbial community analysis were used to evaluate FLZP's effects on endogenous metabolites and gut microbiota, respectively. Correlation analysis investigated the association between metabolites and intestinal flora. A metabolic pathway analysis was undertaken to discover putative FLZP action mechanisms. ResultsFLZP contains 109 components, including liquiritin (584.8176 μg/g), benzoylaconine (16.3087 μg/g), benzoylhypaconine (31.9583), and hypaconitine (8.1160 μg/g). FLZP predominantly regulated seven metabolites and eight metabolic pathways involved in amino acid and nucleotide metabolism, with an emphasis on energy metabolism and gastrointestinal digestion. FLZP also influenced intestinal flora variety, increasing probiotic abundance while decreasing pathogenic bacteria prevalence. An integrated investigation identified associations between changes in certain gut flora and energy metabolism, specifically the tricarboxylic acid (TCA) cycle. ConclusionsFLZP successfully cures UC in SKYD rats by regulating amino acid and energy metabolism. Its positive effects may include altering microbiota composition and metabolite profiles in UC rats with SKYD. These findings shed light on FLZP's mode of action and its implications for UC management.

Potential of Cation Exchange Resin as a Carrier for Anaerobic Consortia in Biohydrogen Fermentation

Cation exchange resin (CER) has been reported to promote sludge fermentation. However, previous studies have typically focused on the effects of CER on sludge properties to enhance fermentation, and the role of CER as a biocarrier for anaerobic consortia during fermentation has been overlooked. Thus, in this study, the potential of gel-type and macro-reticular type CERs to serve as biocarriers in fermentation was investigated. A significant number of anaerobes appeared to be attached to the surfaces of CER during 2-day fermentation. However, an extended fermentation time negatively affected the attachment of anaerobic consortia, suggesting that CER may be a suitable carrier for short-term fermentation processes, such as biohydrogen fermentation. Electrochemical analyses revealed that the electron transfer capacities of CER with attached anaerobes were enhanced after both 2-day and 28-day fermentation periods, with the macro-reticular type CER exhibiting higher electron transfer capacity than the gel-type CER. Fermentation experiments using mixing model substrates with macro-reticular and gel-type CERs with attached anaerobes showed that the macro-reticular type CER was more beneficial for biohydrogen fermentation than the gel-type CER. Further analyses of microbial communities revealed that hydrogen-producing bacteria (i.e., Caloramator, unclassified_f_Caloramatoraceace, and Sporanaerobacter) were more likely to adhere to the macro-reticular type CERs. This outcome confirmed that macro-reticular type CERs have significant potential as a carrier for anaerobic consortia to promote the generation of hydrogen and volatile fatty acids. These findings are expected to provide a reference for using materials as biocarriers to enhance the biohydrogen fermentation of sludge.

Enhancement of membrane filtration performance and mitigation of sludge calcification in an intermittent anaerobic membrane bioreactor treating high-calcium wastewater

Anaerobic membrane bioreactors (AnMBRs) can alleviate the inhibitory effect of sludge calcification on anaerobic process when treating high-calcium wastewater. However, sludge calcification induced by high-calcium wastewater and flocculated sludge formation under reactor aeration shear will inhibit membrane filtration performance. In this study, an intermittently operated AnMBR (A2) was used to treat high-calcium wastewater, and continuously operated AnMBR (A1) was used as the parallel control. When treating 200–1000 mg/L calcium ion wastewater, A2 achieved a stable chemical oxygen demand removal efficiency of 91.8±3.9 %. The methane production of A2 was 188.2±22.5 mL/(gVSS⋅d), which was marginally higher than the continuous AnMBR (A1) methane production of 174.7±11.7 mL/(gVSS⋅d). Analysis of the microbial community demonstrated significant enrichment in hydrolyzing acidifying bacteria and archaea in A2, compared to A1, which played a crucial role in improving the performance of anaerobic process. A1 exhibited a maximum transmembrane pressure (TMP) of 19.6 kPa, and scanning electron microscopy (SEM) analysis revealed the deterioration of membrane fouling due to sludge calcification on the membrane surface. Surprisingly, the maximum TMP of A2 was just 3.6 kPa during the study. When treating 1000 mg/L of high calcium wastewater, the average effluent calcium concentration in A2 was 650 mg/L, which indicated that A2 effectively retained calcium ions. SEM analysis revealed that anaerobic sludge had a tendency to agglomerate, which slowed down membrane fouling in A2. Sludge agglomeration was due to intermittent operation effectively increasing the contact time of sludge with calcium ions, thereby stimulating the protein secretion of extracellular polymers. These results showed that the intermittent operation effectively mitigated membrane fouling. This work provides a new strategy for comprehensively addressing the challenges of high-calcium wastewater and achieving the stable performance of anaerobic reactors.

Biodegradation of four polyolefin plastics in superworms (Larvae of Zophobas atratus) and effects on the gut microbiome

Recent studies have demonstrated superworms (larvae of Zophobas atratus) ability to degrade polyethylene (PE), polystyrene (PS), polyvinyl chloride (PVC), and polypropylene (PP) within their digestive system. This study aimed to compare the ability of superworms to degrade the above four polyolefin plastics over a duration of 30 days. In this study, the degradation rate of PE was the highest, and the final average weight of superworms, as well as the final plastic mass loss consumed by them, significantly increased (73.38 % and 52.33 %, respectively) when PE was fed with wheat bran (1:1 [w/w]). FTIR and TGA indicated the occurrence of oxidation and biodegradation processes in the four polyolefin plastics when exposed to superworms. In addition, the molecular weights (Mw and Mn) of excreted polymer residues decreased by 3.1 % and 2.87 % in PE-fed superworms, suggesting that the depolymerization of PE was not entirely dependent on the gut microbial community. The analysis of the gut microbial communities revealed that the dominant microbial community were different for each type of plastic. The results indicate that the gut microbiome of superworms exhibited remarkable adaptability in degrading various types of plastics, and the intake preferences and efficiency of different plastics are associated with different dominant microbial community species.