Effect of microbial transformation induced by metallic compound additives and temperature variations during composting on suppression of soil-borne pathogens.

Agricultural wastes can be modified by composting and reused in soil to suppress soil-borne pathogens, which was proved to be closely related with microbial parameters. However, the microbial community in compost can be directly altered by temperature variations and metallic compound additives during composting process. The present study collected samples in various stages of the 35-day composting process, in which a study control (no additives) and different metallic compound additives, including magnesium oxide (MgO), alum (AlK(SO4)3), calcium oxide (CaO) and ferrous sulfate (FeSO4), were set in the bespoke compost with cow dung and corn stalk. The results showed that the additives prolonged the composting maturity process, whereas no consistent influence on the temperature variation and microbial community was observed. Temperature variations during composting significantly varied the bacteria and fungi diversity and community, especially the bacteria phyla of Firmicutes and Proteobacteria, while the bacteria were shown similar in Day 14 and Day 35 by PCA analysis. Meanwhile the samples from Day 14 and Day 35 showed stable suppressive effects on R. solani. and F. oxysporum, especially in D14 shown as 73.12%-88.16% and 30.95-58.55%, respectively, which were significantly related with the phyla of Firmicutes and Proteobacteria. In conclusion, temperature variations during composting process had a more significant impact than metallic compound additives on the microbial community and diversity, which resulted in significantly influence on the pathogen suppression. Suitable composting duration could produce effective suppressive products on soil-borne pathogens, for which further study was needed.

Surfactin and fengycin B extracted from Bacillus pumilus W-7 provide protection against potato late blight via distinct and synergistic mechanisms.

Potato late blight caused by Phytophthora infestans is one of the most serious plant diseases worldwide. Cyclic lipopeptides (CLPs) extracted from Bacillus strains exhibit a promising effect in the biocontrol of a variety of phytopathogens. However, the specific inhibitory effects and underlying mechanisms of CLPs against P. infestans are poorly understood. In this study, we showed that Bacillus pumilus W-7 can inhibit the growth of P. infestans mycelium. Two metabolites from W-7, surfactin and fengycin B, were identified using MS/MS. Fengycin B inhibited mycelium growth by inducing mycelium deformations, oxidative damage, and mitochondrial dysfunction. Surfactin induced potato plant defense responses by increasing the expression of the biocontrol genes (pod, pal, and cat) and their enzyme activities (POD, PAL, and CAT). Also, surfactin and fengycin B could exhibit a synergistic inhibitory effect on P. infestans. Taken together, our findings indicate that B. pumilus W-7 and its CLPs are potential environmentally friendly and effective biocontrol agents for the preservation of potato crops. KEY POINTS: • Lipopeptides of surfactin and fengycin B are extracted from Bacillus pumilus W-7. • Fengycin B inhibits Phytophthora infestans mycelium growth in a direct manner. • Surfactin induces potato plant defense responses to control late blight.

Comparing the effects of three in situ methods on nitrogen loss control, temperature dynamics and maturity during composting of agricultural wastes with a stage of temperatures over 70 °C.

The study investigated the effects of three in situ methods for controlling nitrogen loss and maturity with different mechanisms: struvite-based addition (K2HPO4 and MgO, MP), woody peat addition (WP) and intermittent aeration (IA), during composting of vegetable waste (cucumber vine) with temperature over 70 °C to inactivate potential viral pathogens. The experiment was conducted in a 200 L pilot-scale composting system, with which temperature and ammonia emission were recorded in real time, and solid samples were collected and analyzed during the process. The results indicated that the methods of MP and IA reduced the total nitrogen loss by 27.5% and 16.1%, respectively, without inhibitory effects on the temperature, nutrient availability and maturity. The WP method significantly decreased the nitrogen loss but could not maintain the thermophilic stage over 70 °C, because of its influence on the material physio-chemical characteristics caused by woody peat addition. In conclusion, all three methods could promote the maturity process, and 20 days should be adequate for vegetable waste composting with a good nutrient availability. Considering the two factors of reducing nitrogen loss and achieving high temperatures together, we recommended the struvite-based controlling method with the mechanism of chemisorption to reduce nitrogen loss during vegetable waste composting that requires temperatures over 70 °C.

Effects of composting and carbon based materials on carbon and nitrogen loss in the arable land utilization of cow manure and corn stalks.

Recycling organic wastes to arable land as fertilizers has been recognized as a sustainable utilization to reduce environmental pollution. Techniques used for the treatment of organic wastes determine their nutrient contents and thus fertilizer efficiency for agricultural applications. The current study investigated the influences of composting and carbon based materials (biochar and woody peat), on carbon and nitrogen loss in the process of agricultural wastes utilization in the soil batch experiments. The results indicated composting process significantly strengthened the organic matter mineralization, increased the carbon loss rates from 33.46-38.96% to 60.54-86.15% and the nitrogen loss rates from 5.01-22.22% to 48.64-58.16%, dominant lost as carbon dioxide (CO2) and ammonia (NH3) emissions. Addition of carbon based materials could effectively reduce the carbon and nitrogen loss during both composting and soil incubation process. When the composted organic wastes were used in the soil batch experiments, woody peat was more effective to reduce nitrogen loss, while biochar was more effective to control carbon loss. When organic wastes were directly fertilized to soil, biochar could effectively reduce nitrogen loss. These results suggested that fertilizing raw agricultural wastes to with carbon based materials could reduce carbon and nitrogen losses, and increased the nutrient bioavailability in soil in comparison with their farmland application after composting.

Effect of initial material bulk density and easily-degraded organic matter content on temperature changes during composting of cucumber stalk.

To inactivate the potentially pathogenic microorganisms and safely utilize vegetable waste compost, ultra-high temperatures (>70°C) should be maintained during the composting without having an inhibitory effect on maturity. This study investigated the influence of bulk density (part 1) and easily-degraded organic matter content (EDOMC, part 2) on temperature evolution during vegetable waste composting: Part 1: corn straw with different particle sizes was used to achieve different bulk densities in the composting material (BD1-BD3); Part 2: partial or total substitution of the corn straw by corn starch was carried out to obtain different EDOMC (ED1-ED4). The composting experiments were conducted in a lab-scale reactor (1.75kg material) and lasted for 30d. Temperature and CO2 emission were recorded daily, and the organic matter, lignocellulose, microbial activity, germination index (GI) and C/N of the samples were measured at different stages. The highest temperature (65.7°C) in part 1 occurred in the treatment with the bulk density of 0.35g/cm3, which also had the longest thermophilic phase. Bulk density was found to seriously influence the utilization efficiency of O2 and heat transfer through materials, rather than heat production from organic matter degradation. In experiment part 2, the highest temperature was obtained with EDOMC of 45% (71.4°C). Therefore, adjusting the bulk density to 0.35g/cm3 and the easily-degraded organic matter content of the initial material to 45% was the best combination for reaching temperatures above 70°C during composting, with no inhibitory effect on the maturity of the compost product.

A comprehensive association analysis confirms ZMIZ1 to be a susceptibility gene for vitiligo in Chinese population.

BACKGROUND: ZMIZ1 has been shown to be associated with multiple autoimmune diseases and play a role in the development of melanocyte. The association of ZMIZ1 with vitiligo was also suggested, but the evidence did not reach genome-wide significance and has not been confirmed by independent studies. METHODS: A fine mapping analysis of the ZMIZ1 locus was carried out in the dataset of 1117 vitiligo patients and 3437 controls through deep imputation. Ten suggestive SNPs were then analysed in an independent validation cohort of 7458 cases and 7542 controls. SNPs within ZMIZ1 locus were functionally annotated using the ENCODE and RegulomeDB databases and published eQTL dataset of primary immune cells. RESULTS: A genome-wide significant association was discovered at rs1408944 (OR(combined)=1.18, p(combined)=1.38E-09) that locates at a DNAse hypersensitivity site and within a Myb_1 motif carried by the binding sites of six overlapping transcription factors (TFs) within the region. Gene Relationships Across Implicated Loci (GRAIL) analysis revealed biological connectivity between ZMIZ1 and previously discovered susceptibility loci for vitiligo as well as the six TFs. CONCLUSIONS: Our study has confirmed ZMIZ1 as a novel susceptibility locus for vitiligo and further suggested rs1408944 to be the putative causal variant that potentially interrupts TF binding and thus the transcriptional regulation of ZMIZ1.

Quinones-enhanced humification in food waste composting: A novel strategy for hazard mitigation and nitrogen retention.

The harmless and high-value conversion of organic waste are the core problems to be solved by composting technology. This study introduced an innovative method of promoting targeted humification and nitrogen retention in composting by adding p-benzoquinone (PBQ), the composting without any additives was set as control group (CK). The results indicated that the addition of exogenous quinones led to a 30.1% increase in humic acid (HA) content during the heating and thermophilic phases of composting. Spectroscopic analyses confirmed that exogenous quinones form the core skeleton structure of amino-quinones in HA through composting biochemical reactions. This accelerated the transformation of quinones into recalcitrant HA in the early stages of composting, and reduced CO2 and NH3 by 8% and 78%, respectively. Redundancy analysis (RDA) revealed that the decrease in carbon and nitrogen losses primarily correlated with quinones enhancing HA formation and greater nitrogen incorporation into HA (P < 0.05). Furthermore, the compost treated with quinones demonstrated a decrease in phytotoxicity and earthworm mortality, alongside a significant increase in the relative abundance of actinobacteria, which are associated with the humification process. This research establishes and proposes that co-composting with quinones-containing waste is an effective approach for the sustainable recycling of hazardous solid waste.

Mature compost promotes biodegradable plastic degradation and reduces greenhouse gas emission during food waste composting.

Mature compost can promote the transformation of organic matter (OM) and reduce the emission of polluting gases during composting, which provides a viable approach to reduce the environmental impacts of biodegradable plastics (BPs). This study investigated the impact of mature compost on polybutylene adipate terephthalate (PBAT) degradation, greenhouse gas (GHG) emission, and microbial community structure during composting under two treatments with mature compost (MC) and without (CK). Under MC, visible plastic rupture was advanced from day 14 to day 10, and a more pronounced rupture was observed at the end of composting. Compared with CK, the degradation rate of PBAT in MC was increased by 4.44 % during 21 days of composting. Thermobifida, Ureibacillus, and Bacillus, as indicator species under MC treatment, played an important role in PBAT decomposition. Mature compost reduced the total global warming potential (GWP) by 25.91 % via inhibiting the activity of bacteria related to the production of CH4 and N2O. Functional Annotation of Prokaryotic Taxa (FAPROTAX) further revealed that mature compost addition increased relative abundance of bacteria related to multiple carbon (C) cycle functions such as methylotrophy, hydrocarbon degradation and cellulolysis, inhibited nitrite denitrification and denitrification, thus alleviating the emission of GHGs. Overall, mature compost, as an effective additive, exhibits great potential to simultaneously mitigate BP and GHG secondary pollution in co-composting of food waste and PBAT.

Reactivation Risk of Latent Tuberculosis or Inactive Hepatitis B Virus Infection and Effectiveness of Ustekinumab in Chinese Plaque Psoriasis Patients: A 28-Week Retrospective, Observational Study.

Introduction: This study observed the effectiveness of ustekinumab and reactivation risk of concurrent latent tuberculosis infection (LTBI) and inactive hepatitis B virus (HBV) infection in Chinese mainland psoriasis patients on ustekinumab treatment. Methods: This retrospective, multicenter, observational study was conducted in three centers in China. Adult patients with moderate to severe plaque psoriasis were treated with ustekinumab for 28 weeks. The effectiveness endpoint included 75% and 90% improvement in Psoriasis Area Severity Index (PASI75/90) response rate, percentage of PASI improvement, change of absolute PASI score and body surface area involvement (BSA) score, absolute PASI ≤1/3 and Physicians' Global Assessment (PGA)=0/1, as well as Dermatology life quality index (DLQI)=0/1 response rate at week 4, 16 and 28. Screening of tuberculosis and hepatitis were performed at baseline and week 28. Results: A total of 82 patients were enrolled between March 2021 and May 2023 and the number of patients combined with LTBI and inactive HBV infection was 20 and 21 respectively. The PASI75 and PASI90 response rate at week 28 was 95.1% and 81.7% respectively. The mean PASI score decreased from 14.93 ± 12.07 at baseline to 0.78 ± 1.86 at week 28, and the mean BSA score decreased from 21% ± 18% at baseline to 1% ± 2% at week 28 (both P<0.001 compared with baseline). DLQI 0/1 response rate at week 28 was 73.2%. No reactivation of LTBI and inactive HBV infection and also no new-onset tuberculosis and hepatitis B occurred in patients without LTBI and inactive HBV infection at baseline. Conclusion: Ustekinumab demonstrated great effectiveness in Chinese plaque psoriasis patients and good safety in psoriasis concurrent with LTBI and inactive HBV infection under the real-world setting.

5-aminolevulinic acid photodynamic therapy combined with wart curettage treatment for intractable urethral condylomata acuminata. A case report.

Condylomata acuminata (CA) is caused by human papillomavirus (HPV). It is one of the most common sexually transmitted diseases (STD). The lesions mainly occur in the external genitalia and perianal areas, rarely involves in urethral and usually localized at the distal 3 cm of the urethral orifice. Because of the special anatomical site, treating urethral CA is challenging and it has high recurrence rate after treatment. 5-aminolevulinic acid photodynamic therapy (ALA-PDT) can successfully treat urethral CA, however, the experience of using ALA-PDT combined with wart curettage to treat intractable urethral CA is still very limited. In here, we reported an intractable urethral CA case with effective remission after receiving combination therapy. Wart curettage combine with ALA-PDT is an expeditious, economical, and well-tolerated treatment method.

Self-healing hydrogel based on polyphosphate-conjugated pectin with hemostatic property for wound healing applications.

Self-healing hydrogels have important application in hemostasis and wound repairing. In this research, pectin based self-healing hydrogel was fabricated with conjugated polyphosphate for hemostatic and wound healing applications. The hydrogel formed without any stimulus and hydrogel kept its biocompatibility; at the same time, the hydrogel degraded completely by enzyme and in vivo. The polyphosphate conjugated hydrogel also showed self-healing property and sustained release performance with strong coagulation characteristic. More importantly, the in vivo experiment revealed that the polyphosphate conjugated hydrogel reduced the blood loss and hemostasis time in hemorrhage model; meanwhile, the hydrogel accelerated the wound repairing rate of the open wound by preventing bacterial invasion. Altogether, the PolyP conjugated hemostatic pectin-based hydrogel is a good candidate as wound dressing material applied in clinic or open wound repairing.

Light emitting CMC-CHO based self-healing hydrogel with injectability for in vivo wound repairing applications.

Self-healing hydrogels with biodegradability have great potential biomedical application in drug loading and delivery, wound dressing and tissue engineering. In this research, biodegradable hydrogels were designed from oxidized CMC (CMC-CHO) and PEO23 dinaphthoate hydrazide (PEO23 DNH) with naphthalene structure for potential bio-imaging purpose. Results showed that the gelation time of this self-healing hydrogels was very fit for in situ injectable applications for drug loading and controlled release. The hydrogels also showed excellent biocompatibility because all the components and the acylhydrazone bond are biocompatible. Moreover, the in vitro and in vivo drug release study revealed the CMC-CHO based hydrogels could reduce the acute toxicity of the drugs with a controlled and sustained release manner. The hydrogel also showed hemostatic activity by sealing effect and mEGF loaded hydrogel accelerated the wound repairing efficacy. All above result proved the CMC-CHO/PEO23 DNH hydrogel with luminescent property have great application property in bioscience and biotechnology.

The role of the biogas slurry microbial communities in suppressing fusarium wilt of cucumber.

The clarification of the suppressive effect of biogas slurries (BSs) on soil-borne plant pathogens is needed for their large-scale use as a biocontrol tool in potting soil in order to understand the mechanisms of suppression. In this study, pig manure biogas slurry (PS) and vinasse biogas slurry (VS) were used to conduct assays of pathogen mycelial growth suppression and pot experiment to evaluate their effects on the growth of Fusarium. oxysporum f. sp. cucumerinum (FOC) mycelia and cucumber fusarium wilt. The microbial communities of the PS and VS were deeply analyzed to explore the key taxa and potential mechanisms. Results showed that the PS and VS have similar suppression on FOC mycelia and on the control efficiency, while they were significantly weakened when the PS and VS were used after sterilization. The microbial parameters of the two BSs were obviously different, and functional microbial taxa for disease resistance were observed in the two BSs. Spearman correlation showed that genera of the Pseudomonas, Ochrobactrum, Papiliotrema, etc., were the suppression-related taxa in the PS, while Leucobacter, unclassified_Microbacteriaceae, etc. in the VS. Overall, various key taxa in the PS and VS produced similar suppression on cucumber fusarium wilt.

Self-healing pectin/cellulose hydrogel loaded with limonin as TMEM16A inhibitor for lung adenocarcinoma treatment.

Lung cancer as one of the highest incident malignant tumors did not receive satisfactory chemotherapy due to lack of specific drug targets and targeted drugs. This study screened a new effective lung tumor inhibitor limonin from herbal medicine, which inhibited proliferation and promoted apoptosis of lung adenocarcinoma cells by targeting specific high expressed TMEM16A ion channel. Moreover, a novel biodegradable self-healing hydrogel was prepared from acylhydrazide functionalized carboxymethyl cellulose (CMC-AH) and oxidized pectin (pec-CHO) to reduce the side effects of the limonin to the body. The hydrogels showed fast gelation, good biocompatibility and sustained limonin release property. The limonin-loaded hydrogel significantly inhibited the growth of lung adenocarcinoma in xenografts mice because the limonin inhibited the proliferation, migration and promoted apoptosis of LA795 cells, and eliminated the acute toxicity through sustained release from the hydrogel. Combined the antitumor performance of the limonin and sustained release of pec-CHO/CMC-AH hydrogel, this limonin/hydrogel system achieved satisfactory antitumor effect and eliminated side effects in vivo. Therefore, this system has great potential application for enhanced lung adenocarcinoma therapy.

Detection of Circulating VZV-Glycoprotein E-Specific Antibodies by Chemiluminescent Immunoassay (CLIA) for Varicella-Zoster Diagnosis.

Varicella and herpes zoster are mild symptoms-associated diseases caused by varicella-zoster virus (VZV). They often cause severe complications (disseminated zoster), leading to death when diagnoses and treatment are delayed. However, most commercial VZV diagnostic tests have low sensitivity, and the most sensitive tests are unevenly available worldwide. Here, we developed and validated a highly sensitive VZV diagnostic kit based on the chemiluminescent immunoassay (CLIA) approach. VZV-glycoprotein E (gE) was used to develop a CLIA diagnostic approach for detecting VZV-specific IgA, IgG, and IgM. The kit was tested with 62 blood samples from 29 VZV-patients classified by standard ELISA into true-positive and equivocal groups and 453 blood samples from VZV-negative individuals. The diagnostic accuracy of the CLIA kit was evaluated by receiver-operating characteristic (ROC) analysis. The relationships of immunoglobulin-isotype levels between the two groups and with patient age ranges were analyzed. Overall, the developed CLIA-based diagnostic kit demonstrated the detection of VZV-specific immunoglobulin titers depending on sample dilution. From the ELISA-based true-positive patient samples, the diagnostic approach showed sensitivities of 95.2%, 95.2%, and 97.6% and specificities of 98.0%, 100%, and 98.9% for the detection of VZV-gE-specific IgA, IgG, and IgM, respectively. Combining IgM to IgG and IgA detection improved diagnostic accuracy. Comparative analyses on diagnosing patients with equivocal results displaying very low immunoglobulin titers revealed that the CLIA-based diagnostic approach is overall more sensitive than ELISA. In the presence of typical VZV symptoms, CLIA-based detection of high titer of IgM and low titer of IgA/IgG suggested the equivocal patients experienced primary VZV infection. Furthermore, while no difference in IgA/IgG level was found regarding patient age, IgM level was significantly higher in young adults. The CLIA approach-based detection kit for diagnosing VZV-gE-specific IgA, IgG, and IgM is simple, suitable for high-throughput routine analysis situations, and provides enhanced specificity compared to ELISA.

Composting with biochar or woody peat addition reduces phosphorus bioavailability.

Biochar and woody peat have been recognized as an additive to reduce carbon and nitrogen loss during composting. Yet little is known about their influences on the transformation of phosphorus (P) fractions in composting. This study investigated the quantitative and qualitative changes in different P forms during composting with adding biochar or woody peat using sequential extraction and P K-edge X-ray absorption near-edge structure (XANES). The results showed that compost products from the treatment with adding woody peat had a higher HA/FA (the ratio of humic acid to fulvic acid) compared to biochar treatment and the control, suggesting that the addition of woody peat might benefit the humification process of composting. Sequential extraction and XANES illustrated that adding biochar or woody peat limited the P availability. Biochar increased the proportion of Pi and woody peat decreased the conversion from Po to Pi compared to the control. Structural equation modeling and redundancy analysis suggested that biochar improved the refractory P based on the indirect effects of NH4+-N by regulating microbial community, while woody peat was beneficial for Po accumulation by affecting humic acid. Taken together, this research provides basis for regulating the nutrient level of carbon, nitrogen, and phosphorus in composts and reducing environmental risks.

5-aminolevulinic acid photodynamic therapy and holmium laser treatment for intraurethral condylomata acuminata in a renal transplant patient.

Condylomata acuminata (CA) caused by human papillomavirus, often involves the external genitalia, perianal skin, and other moist mucous membranes. Urethral involvement is uncommon and little recognized, and usually limited to the distal 3 cm of the meatus. It is difficult to treat CA involving the urethra because of the anatomical location, risk of complications and recurrence. One effective method for the treatment of CA located at the urinary meatus is 5-aminolevulinic acid photodynamic therapy (ALA-PDT). However, experience of using this method for the treatment of whole urethral CA is still very limited. Herein, we treated a whole urethral CA successfully with photodynamic and holmium laser therapies. The case of a 25-year-old patient who underwent kidney transplant effected by intraurethral CA is presented and discussed. Catheter implantation and (or) immunosuppression treatment increases the risk of urethral condyloma acuminatum. The ALA-PDT is a safe, straightforward, effective, and well-tolerated treatment procedure for intraurethral CA. ALA-PDT combined with holmium laser treatment can successfully treat kidney transplant patients with intraurethral CA.

Pretreatment by composting increased the utilization proportion of pig manure biogas digestate and improved the seedling substrate quality.

Anaerobic digestion of organic residues has the potential to significantly contribute to a shift from fossil to renewable energy, while the remaining biogas digestate need to be treated or used for a second time. In this study, the pig manure biogas digestate (PMBD) was evaluated as a potential part of seedling substrates and composting was considered a pretreating method to improve its characters. Composting was carried out firstly in a forced aeration composting system (100 L), in which perlite and sawdust were used as additives in different proportions separately or together. Based on the comparison of the physicochemical characters of different seedling substrates formulas mixed with PMBD or pig manure biogas digestate pretreated by composting (CPMBD), selected seedling substrates were analyzed by bioassay experiment. The results showed that pretreatment by composting and the additives (perlite and sawdust) used in composting decreased the pH value of PMBD and make it suitable for seedling substrates, especially composted with perlite and sawdust. Both PMBD and CPMBD with low proportion in the substrates improved plant growth of lettuce and tomato, while CPMBD was better than PMBD. However, when the proportions of PMBD was increased more than 20% and CPMBD was increased more than 40%, plant growth inhibition was observed. Tomato was more sensitive than lettuce to the physicochemical characters of the substrate. In summary, PMBD pretreated by composting not only increases the uses of digestate, but also enhances plant growth and hence yield.

[Study of nondestructive and fast identification of fabric fibers using near infrared spectroscopy].

A fast and nondestructive identification method to distinguish different types of fabric fibers is proposed in the present paper. A total of 214 fabric fiber samples, including wool, cashmere, terylene, polyamide, polyurethane, silk, flax, linen, cotton, viscose, cotton-flax blending, terylene-cotton blending, and wool-cashmere blending, were collected from Beijing Textile Fibre Inspection Institute. They contain yarns, raw wool or cashmere, and various fabric straps with different colors and different braid patterns. Sample presentation for measuring near infrared spectra of various textile fibers was tried to reduce the impact from the ununiformity of polymorphous fabric structure. Spectral data were pretreated using multiplicative signal correction (MSC) to reduce the influence of spectral noise and baseline shift. Classification of 12 kinds of fabric fibers in various braid patterns was studied using minimum spanning tree method and soft independent modeling of class analogy (SIMCA) classification based on principal component analysis of NIR spectra. The minimum spanning tree for the spectra of total samples shows that the samples in the same type fall almost into one cluster, but there are overlaps between some two different clusters of fabric fibers with very similar chemical compositions, such as wool and cashmere. Complete discrimination between cashmere and wool has been achieved using SIMCA. The results show that nondestructive and fast identification of fabric fibers using near infrared spectral technique is potentially feasible.

Effects of carbon-based additives and ventilation rate on nitrogen loss and microbial community during chicken manure composting.

Aerobic composting is a sustainable method for chicken manure recycling, while its unsuitable porosity and carbon to nitrogen ratio (C/N) may result in high nitrogen loss and incomplete composting. With the aim to investigate the effects of carbon-based additives and two ventilation rates on chicken manure composting and microbial community, two series of treatments were set up for chicken manure composting, in order to investigate their effects on the biodegradation process, ammonia (NH3) emission, nitrogen loss, physiochemical properties and microbial community. The results showed that additives and ventilation rates set in the current study influenced the carbon dioxide (CO2) production from the 2nd week and also the physiochemical parameters during the entire process, while no inhibitory effect on the maturity were observed. With woody peat as additive, the NH3 emission amount and nitrogen loss rate were shown as 15.86 mg and 4.02%, less than those in other treatments, 31.08-80.13 mg and 24.26-34.24%, respectively. The high aeration rate increased the NH3 emission and nitrogen loss, which were varied when the additives were different. The terminal restriction fragment length polymorphism (T-RFLP) results showed that the additives and the ventilation rates changed the microbial community, while the prominent microbial clones belonged to the class of Bacilli and Clostridia (in the phylum of Firmicutes), and Alphaproteobacteria, Deltaproteobacteria and Gammaproteobacteria (in the phylum of Proteobacteria). Bacillus spp. was observed to be the most dominant bacteria in all the composting stages and treatments. It was concluded that woody peat could improve chicken manure composting more than other additives, especially on reducing nitrogen loss, meanwhile 0.18 L‧min-1‧kg-1 DM was suitable for various additives. Therefore, suitable additive and aeration rate could be used in practical application, which could significantly reduce nitrogen loss without influence on the compos maturity process.