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Temperature is known as one of the abiotic factors that can affect mold growth. Many mold growth prediction models consider temperature as one of the parameters that can significantly impact mold growth indoors, and hence temperature has been targeted by different indoor mold prevention strategies on different premises. For example, European guidelines for libraries suggest a temperature of 19 °C to preserve books. However, running low temperature air-conditioning (AC) costs substantially more energy, and thus a higher temperature (e.g., 25.5 °C) has been regularly proposed as the recommended indoor temperature for general indoor environments in Hong Kong. It is, therefore, needed to understand whether or not the reduction of indoor temperature would lead to better effectiveness of mold prevention. Using Cladosporium cladosporioides (C. cladosporioides) as the model, its germinating spores were challenged in C. cladosporioides to wet-dry cycles with different combinations of relative humidity (RH, 40%, 60% and 80%) and temperature (19 °C and 28 °C) levels. The survival, lipid peroxidation and catalase (CAT) activity of the treated spores were monitored and compared. C. cladosporioides spores showed similar levels of viability, lipid peroxidation and CAT activity when they were exposed to 19 °C and 28 °C at the same RH, but substantially lower survival and higher oxidative stress were observed under the wet-dry cycles with 40% RH dry periods compared with 60% and 80% RH at both temperatures, suggesting that indoor temperature does not tend to affect the resistance of C. cladosporioides to wet-dry cycles as significantly as the RH level of the dry period. Collectively, this study suggests a more important role for moisture over temperature in indoor mold prevention. The outcome of this study may facilitate the sustainable management of indoor mold problems in buildings. [ABSTRACT FROM AUTHOR]

Moisture is one of the critical abiotic factors that can affect mold growth. Indoor humidity is typically fluctuating, which renders a transient water supply for mold growth. Understanding mold growth under water dynamics and its underlying mechanisms can help in the development of novel and sustainable mold prevention strategies. In this study, pre‐germination and germinated spores of Cladosporium cladosporioides were exposed to daily wet‐dry cycles with different combinations of wetting and drying duration. Afterward, growth delay, cellular H2O2 concentration, and catalase (CAT) activity were measured and compared. We found that under daily wet‐dry cycles, the longer the growth delay was observed, the higher the cellular H2O2 concentration was detected, with the 12‐12 wet‐dry cycle (12‐hour wet and 12‐hour dry) showing the longest growth delay and highest cellular H2O2 production. A positive correlation between cellular H2O2 concentration and growth delay was suggested by Pearson correlation coefficient and linear regression analysis (P <.0001, R2 = 0.85). Furthermore, under daily wet‐dry cycles, molds derived from pre‐germination spores generally exhibited shorter growth delay, lower cellular H2O2 concentration, and higher CAT activity than molds developed from germinated spores. These results together suggest that the growth delay of C. cladosporioides under water dynamics is associated with oxidative stress. [ABSTRACT FROM AUTHOR]

Mold contamination is one of the most important causes for indoor air pollution. Previous studies have indicated the feasibility of employing wet-dry cycles, a special water treatment approach in indoor environments, to control indoor mold contamination. However, the underlying mechanisms regulating the responses of indoor molds to changing moisture conditions remains to be elucidated. Here, we studied the mechanisms regulating the responses to wet-dry cycles (termed as moisture dynamics) in Aspergillus penicillioides , Cladosporium cladosporioides , and Aspergillus niger. First, the dormant spores of each mold species were grown to the swollen stage. Next, swollen spores were incubated at different water activity (a w) levels (0.4, 0.6 and 0.8 a w) for up to 15 days. Afterward, the viability, lipid peroxidation and antioxidant activities (both enzymatic and non-enzymatic) of treated molds were determined. Our results show that the mold species that survived better under moisture dynamics also encountered less oxidative damage and exhibited stronger antioxidant activities. Moreover, lower RH imposed severer oxidative stress to C. cladosporioides and A. niger. Pearson correlation coefficient indicate significant correlations between oxidative stress and a w of dry periods, oxidative damage and mold survival, as well as oxidative responses and mold survival. Collectively, these results imply that oxidative stress adaptation regulates the viability of A. penicillioides , C. cladosporioides , and A. niger in response to moisture dynamics. Our findings facilitate the development of novel engineering solutions for indoor air pollution. [Display omitted] • Indoor molds are pungent contaminants that deteriorate indoor air quality. • Oxidative stress adaptation is crucial for indoor mold survival under moisture dynamics. • Antioxidant responses may be used as targets to improve indoor air quality. [ABSTRACT FROM AUTHOR]

Two thermophilic bacterial strains, Bacillus subtilis BUM (BUM) and Mycobacterium vanbaalenii BU42 (BU42), were tested for their potential in biodegradation of benzo[a]pyrene. Neither BUM nor BU42 utilized benzo[a]pyrene as the sole substrate under thermophilic condition. In the presence of 50, 250, and 500 mg L−1 phenanthrene, the biodegradation of benzo[a]pyrene by BUM occurred and removals in 30 days were 14.8%, 38.8%, and 63.6%, respectively. This is the first report on the biodegradation of benzo[a]pyrene by isolated thermophilic microorganism. The BUM strain was further tested for its ability in a soil composting system. Within a composting period of 42 days, removal of benzo[a]pyrene in the absence of BUM was 30.3%. Treatment with the inoculation of BUM significantly increased the removal of benzo[a]pyrene to 52.2%. Maximum zero-order degradation rates of benzo[a]pyrene by BUM in aqueous biodegradation experiment and soil composting system were 12.3 mg L−1 day−1 and 9.7 mg kg−1 day−1, respectively, which were significantly greater than most of the reported degradation rates by mesophiles. Experimental results affirmed that the strain BUM can effectively degrade benzo[a]pyrene under thermophilic condition. [ABSTRACT FROM AUTHOR]

Cadmium uptake potential of Brassica napus cocropped with B. parachinensis or Zea mays plants in split pot (allow the solutes to pass but prevent the interaction of roots between compartments) experiments was evaluated. Plants were grown in split pots filled with soil spiked at 0, 3, 6, 12, 25 and 50mg Cd/kg soil. Biomass and Cd uptake were detemined after 6 weeks, and rhizospheric soil solutions, extracted using soil probes, were analyzed for pH and water soluble Cd at weekly intervals. Cadmium treatments affected the biomass. Cadmium concentration in the shoots of B. napus was higher when cocropped with B. parachinensis and significantly higher with Z. mays; however, the biomass was negatively affected implying the higher nutrient apportionment to the crop plants than B. napus. Concentration of Cd in B. napus was higher in shoots than in roots as revealed by shoot/root Cd quotient and was always >1; the quotient for B. parachinensis was ¿1 and that of Z. mays was <1, indicating the potential of Brassicaceae members to translocate the Cd to aboveground tissue. Results indicate the feasibility of cocropping method to clean the Cd contaminated soils. [Copyright &y& Elsevier]

The exploration of sediment pollution caused by PAHs and its impact on microbial communities can provide valuable insights for the remediation of sediments. The spatial distribution of PAHs and their impact on the microbial community within the Pearl River Estuary were investigated in this study. The findings revealed that the total concentration ranges of 16 PAHs were between 24.26 and 3075.93 ng/g, with naphthalene, fluorene, and phenanthrene potentially exerting adverse biological effects. More PAHs were found to accumulate in subsurface sediments, and their average accumulation rates gradually decreased as the number of rings in PAHs increased, ranging from 180 % for 2-ring to 36 % for 6-ring. The phyla Proteobacteria, Bacteroidetes, Actinobacteria, and Chloroflexi were found to dominate both surface and subsurface sediments The correlation between microbial genera and PAHs contents was weak in sediments with low levels of PAHs contamination, while a more significant positive relationship was observed in sediments with high levels of PAHs contamination. The physicochemical properties of sediments, such as pH, soil structure and Cu significantly influence bacterial community composition in highly contaminated sediments. Additionally, the network analysis revealed that certain bacterial genera, including Novosphingobium , Robiginitalea and Synechococcus_CC9902 , played a pivotal role in the degradation of PAHs. These findings are significant in comprehending the correlation between bacterial communities and environmental factors in intertidal ecosystems, and establish a scientific foundation for bioremediation of intertidal zones. [Display omitted] • Nap, Flu and Phe may have harmful effects on intertidal sediments. • More PAHs accumulated in subsurface sediments. • Microbial assembly primarily responds to PAHs, pH, sediment structure and Cu. • Cyanobacteriota, Proteobacteria, and Bacteroidota can degrade PAHs. [ABSTRACT FROM AUTHOR]

Abstract: This study aimed at investigating the synergistic effect of temperature and biosurfactant on the biodegradation of phenanthrene in bioslurry. Bench-scale bioslurry experiments were conducted at 25 and 55°C. The desorption rate coefficients of phenanthrene (K des) obtained using the pseudo-first order model were 0.0026 and 0.0035kgmg−1 h−1 at 25 and 55°C, respectively. Addition of 1500mgL−1 biosurfactant, produced by Acinetobacter calcoaceticus BU03, marginally increased the K des at 25°C since most of biosurfactant was sorbed onto soil; however, significantly increased the K des to 0.0087kgmg−1 h−1 at 55°C as the thermophilic temperature reduced the adsorption of the biosurfactant onto soil and subsequently enhanced the desorption of phenanthrene. The biodegradation of phenanthrene well fitted pseudo-first order kinetics based on the assumption that biodegradation was limited by the desorption. About 78.7% of phenanthrene was degraded in 30 days at 25°C; and addition of biosurfactant did not affect the biodegradation. However, addition of the biosurfactant or inoculation of A. calcoaceticus BU03 at 55°C significantly enhanced the biodegradation by increasing the K des. Results indicate that synergistic application of thermophilic temperature and biosurfactant or inoculation of biosurfactant producing microorganisms is an effective and innovative method to enhance the efficiency of PAH degradation in bioslurry system. [Copyright &y& Elsevier]

Abstract: The effects of rhamnolipids produced by Pseudomonas aeruginosa ATCC9027 on the cell surface hydrophobicity (CSH) and the biodegradation of phenanthrene by two thermophilic bacteria, Bacillus subtilis BUM and P. aeruginosa P-CG3, and mixed inoculation of these two strains were investigated. Rhamnolipids significantly reduced the CSH of the hydrophobic BUM and resulted in a noticeable lag period in the biodegradation. However, they significantly increased the CSH and enhanced the biodegradation for the hydrophilic P-CG3. In the absence of rhamnolipids, a mixed inoculation of BUM and P-CG3 removed 82.2% of phenanthrene within 30days and the major contributor of the biodegradation was BUM (rapid degrader) while the growth of P-CG3 (slow degrader) was suppressed. Addition of rhamnolipids promoted the surfactant-mediated-uptake of phenanthrene by P-CG3 but inhibited the uptake through direct contact by BUM. This resulted in the domination of P-CG3 during the initial stage of biodegradation and enhanced the biodegradation to 92.7%. [Copyright &y& Elsevier]

• Maximum methane yield was found in co-digester of TS 6%. • Excess PM leads to the accumulation of VFAs and ammonia. • More balanced C/N ratio is obtained in the co-digestion. • Methane yield is negatively correlated with F/I, TAN, FAN and VFA/TIC. This study assessed the digester stability and overall methane production of co-digestion of sewage sludge (SS) and pig manure (PM). Four different ratios of PM were mixed with SS to reach different final concentrations of total solids (TS), i.e. 4%, 6%, 8% and 10%. Volatile solids (VS) reduction rate decreased along with an increase in TS%, and the maximum cumulative methane yield of 342 mL/g VS rem was obtained in treatment with TS of 6%. When TS was ≥ 8%, accumulation of volatile fatty acids (VFAs), free ammonium nitrogen (FAN) and total ammonium nitrogen (TAN) were observed. At a TS content of 10%, VFAs accumulated to > 20000 mg/L and the highest FAN was 481 mg/L. The suppression of methanogenesis was negatively correlated with FAN and VFA/TIC (P < 0.05). Co-digestion demonstrated to be an effective way to improve the methane yield from SS due to the enriched biodegradable organic substance and more balanced C/N ratio by incorporating PM. [ABSTRACT FROM AUTHOR]

Glucose isomerization to fructose is crucial for its application in food industry and biorefinery. Herein, strategies for developing MgO-biochar catalysts to convert glucose to fructose were explored and optimized with an emphasis on the influence of synthesis method on the stability of the catalyst. Despite the favorable activity exhibited by all catalysts, the embedding of MgO on the surface, loading onto porous structures, or incorporating into a carbon framework significantly diminished the catalytic activity and stability of magnesium species. The one-step synthesis approach facilitates the uniform distribution of MgO nanoparticles on the biochar matrix, enhancing their interactions and preventing Mg leaching compared to MgO-biochar prepared through two-step methods. After optimization, fructose yield exceeding 26% and a selectivity of 91% were obtained under mild conditions of 80 ℃ for 2 h in water. In summary, the effective anchoring of MgO on the biochar exhibited dual effects for enhanced catalytic activity and stability. [Display omitted] • MgO-biochar catalysts were synthesized for glucose isomerization to fructose. • Three synthesis strategies were employed to optimize the catalytic performance. • MgO-biochar prepared by one-step approach exhibited the best catalytic performance. • MgO load position affects activity and stability of the catalyst. [ABSTRACT FROM AUTHOR]

Glucose isomerization to fructose is crucial for its application in food industry and biorefinery. Herein, strategies for developing MgO-biochar catalysts to convert glucose to fructose were explored and optimized with an emphasis on the influence of synthesis method on the stability of the catalyst. Despite the favorable activity exhibited by all catalysts, the embedding of MgO on the surface, loading onto porous structures, or incorporating into a carbon framework significantly diminished the catalytic activity and stability of magnesium species. The one-step synthesis approach facilitates the uniform distribution of MgO nanoparticles on the biochar matrix, enhancing their interactions and preventing Mg leaching compared to MgO-biochar prepared through two-step methods. After optimization, fructose yield exceeding 26% and a selectivity of 91% were obtained under mild conditions of 80 ℃ for 2 h in water. In summary, the effective anchoring of MgO on the biochar exhibited dual effects for enhanced catalytic activity and stability. [Display omitted] • MgO-biochar catalysts were synthesized for glucose isomerization to fructose. • Three synthesis strategies were employed to optimize the catalytic performance. • MgO-biochar prepared by one-step approach exhibited the best catalytic performance. • MgO load position affects activity and stability of the catalyst. [ABSTRACT FROM AUTHOR]

The study investigated the effect of in-vessel composting process on Hanwoo manure in two different South Korea regions (Pyeongchang and Goechang) with sawdust using vertical cylindrical in-vessel bioreactor for 42 days. The stability and quality of Hanwoo manure in both regions were improved and confirmed through the positive changes in physico-chemical and phytotoxic properties using different commercial seed crops. The pH and electrical conductivity (EC, ds/m) of composted manure in both regions were slightly increased. At the same time, carbon:nitrogen (C:N) ratio and ammonium nitrogen:nitrate nitrogen (NH 4 + -N:NO 3 − -N) ratio decreased to 13.4–16.1 and 0.36–0.37, respectively. The germination index (GI, %) index was recorded in the range of 67.6–120.9%, which was greater than 50%, indicating phytotoxin-free compost. Although, composted manure values in Goechang region were better in significant parameters, overall results confirmed that the composting process could lead to complete maturation of the composted product in both regions. [ABSTRACT FROM AUTHOR]

The study investigated the effect of different initial moisture (IM) content (55, 60, 65, and 70%) of composting mixtures (swine manure and sawdust) for the production of nutrient rich manure, and the recovery of ammonia through a condensation process using a vertical cylindrical in-vessel composter for 56 days. The composting resulted in a significant reduction in C:N ratio and electrical conductivity (EC), with a slight increase in pH in all products. The NH 3 were emitted notably, and at the same time the NO 3 − -N concentration gradually increased with the reduction of NH 4 + -N in the composting mixtures. The overall results confirmed, the 65% IM showed the maximum nutritional yield, maturity and non-phytotoxic effects ( Lycopersicon esculentum L.), with the results of ideal compost product in the following order of IM: 65% > 60% > 70% > 55%. Finally, the recovered condensed ammonia contained considerable ammonium nitrogen concentrations and could be used as fertilizer. [ABSTRACT FROM AUTHOR]

This study explores the use of materials such as chitosan (chit), polyaniline (PANI) and titanium carbide (TC) as anode materials for microbial fuel cells. Nickel foam (NF) was used as the base anode substrate. Four different types of anodes (NF, NF/PANI, NF/PANI/TC, NF/PANI/TC/Chit) are thus prepared and used in batch type microbial fuel cells operated with a mixed consortium of Acetobacter aceti and Gluconobacter roseus as the biocatalysts and bad wine as a feedstock. A maximum power density of 18.8 W m −3 (≈2.3 times higher than NF) was obtained in the case of the anode modified with a composite of PANI/TC/Chit. The MFCs running under a constant external resistance of (50 Ω) yielded 14.7% coulombic efficiency with a maximum chemical oxygen demand (COD) removal of 87–93%. The overall results suggest that the catalytic materials embedded in the chitosan matrix show the best performance and have potentials for further development. [ABSTRACT FROM AUTHOR]

This study aimed at manipulating ionic conductivity (EC) to harvest the maximum electrical energy from seawater-based domestic wastewater sewage sludge (SWS), unique to only a few cities, through microbial fuel cell (MFC). SWS has never been investigated as a MFC substrate before, and thus the influence of high in-situ EC on the energy recovery was unknown. In this study, the EC of the SWS was reduced through mixing it with fresh water-based domestic wastewater sewage sludge (FWS) or diluted 50% using deionized water while FWS and SWS were individually served as reference treatments. SWS:FWS mix (1:1) exhibited a maximum Coulombic efficiency of 28.6 ± 0.5% at a COD removal of 59 ± 3% while the peak power density was 20-fold higher than FWS. The improved performance was due to the lower ohmic internal resistance (36.8 ± 4.2 Ω) and optimal conductivity (12.8 ± 0.2 mS cm −1 ). Therefore, dilution with FWS could enhance energy recovery from SWS. [ABSTRACT FROM AUTHOR]

• Various on-site biogenic CO 2 sequestration scenarios are discussed for AD. • Wolf cycle and acetyl-CoA pathways are the main CO 2 fixation mechanisms. • CO 2 capture scenarios for single-/two- phase anaerobic digestion are considered. • Influening factors are discussed for exogenous H 2 mediated CO 2 bioconversion to CH 4. • Flow of carbon and reductant electrons needs to be clarified in-depth. The advantages of anaerobic digestion (AD) technology in organic solid waste treatment for bioenergy recovery are evidenced in worldwide. Recently, more attention has been paid to on-site biogas research, as well as biogenic CO 2 sequestration from AD plant, to promote "carbon neutral". Single-phase and two-phase AD system can be incorporated with various CO 2 bioconversion technologies through H 2 mediated CO 2 bioconversion (in-situ and ex-situ biogas upgrading), or other emerging strategies for CO 2 fixation without exogenous H 2 injection; these include in-situ direct interspecies electron transfer reinforcement, electromethanogenesis, and off-gas reutilization. The existing and potential scenarios for on-site CO 2 bio-sequestration within the AD framework are reviewed from the perspectives of metabolic pathways, functional microorganisms, the limitations on reaction kinetics. This review concluded that on-site CO 2 bio-sequestration is a promising solution to reduce greenhouse gas emissions and increase renewable energy recovery. [ABSTRACT FROM AUTHOR]

This paper presents a comprehensive review of the detection of aflatoxin compounds using carbon allotrope-based sensors. Although aflatoxin M1 and its derivative aflatoxin B1 compounds have been primarily found in milk and other food products, their presence above a threshold concentration causes disastrous health-related anomalies in human beings, such as growth impairment, underweight and even carcinogenic and immunosuppressive effects. Among the many sensors developed to detect the presence of these compounds, the employment of certain carbon allotropes, such as carbon nanotubes (CNTs) and graphene, has been highly preferred due to their enhanced electromechanical properties. These conductive nanomaterials have shown excellent quantitative performance in terms of sensitivity and selectivity for the chosen aflatoxin compounds. This paper elucidates some of the significant examples of the CNTs and graphene-based sensors measuring Aflatoxin M1 (ATM1) and Aflatoxin B1 (AFB1) compounds at low concentrations. The fabrication technique and performance of each of the sensors are shown here, as well as some of the challenges existing with the current sensors. [ABSTRACT FROM AUTHOR]

• Impacts of hydrochar and pyrochar on anaerobic digestion were compared. • Both hydrochar and pyrochar present positive effects. • The maximum methane yield of 308.4 mL/g VS was found in HTC digester. • Methane yield of HTC was 27% and 49% higher than HC and the control reactor. • Superiority of hydrochar is related to its more abundant surface functional groups. Four kinds of biochar were obtained by pyrolysis carbonization and hydrothermal carbonization from swine manure digestate, i.e. pyrochar (HC, HC-Fe) and hydrochar (HTC, HTC-Fe). Batch fermentation was conducted to compare their effects on the co-digestion of sewage sludge and swine manure. Both pyrochar and hydrochar present positive effect on methane production, nevertheless the higher methane yields were obtained in HTC and HTC-Fe digesters. No advantage was observed for the iron impregnation. The maximum methane yield was 308.4 mL/g VS in HTC digester, which was 27% and 49% higher than HC and Control, respectively. The surface functional groups of hydrochar are more abundant than pyrochar, which is favorable for promoting the syntrophic anaerobic metabolism, as revealed by the promoted substrate hydrolysis and VFAs consumption rate. Thus, it is proposed to convert swine manure digestate to hydrochar, which can be recirculated back to the AD reactor to increase the digestion efficiency. [ABSTRACT FROM AUTHOR]