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The unstable carbon release rate and secondary pollutants of agricultural wastes lead to substandard effluent quality, and the mechanism of carbon and secondary pollutant release as well as denitrification efficiency of agricultural wastes can be clarified to facilitate their wide application. In this study, six common agricultural wastes (corn cob (CC), loofah sponge (LS), peanut shells (PS), corn stover (CS), rice straw, wheat straw) were selected, with high total cellulose contents of 61.59–70.68%, and the cumulative carbon releases of 11.333–41.547 mg (g L)−1 in 168 h, which basically followed the second-order reaction kinetics and the Ritger–Peppas equation. The TN and TP contents released from several wastes were low and had little effect on denitrification, but the high-color substances released from straw wastes might affect the effluent in the denitrification process. The soluble organic matter of CC, LS, PS and CS are mainly protein-derived compounds, which are more favorable for microbial decomposition and utilization. In the denitrification experiment, denitrification efficiency was higher with CC and straw waste as carbon sources. The results of this study are expected to provide a theoretical basis and data support for the use of agricultural waste as a carbon source for denitrification. [ABSTRACT FROM AUTHOR]

Carbon nanotubes (CNTs) exhibit exceptional properties, making them invaluable across various industries. Chemical vapor deposition (CVD) is one of the most widely used methods for producing CNTs. This study investigates key factors such as temperature, pressure, and carbon source that influence CNT synthesis. By understanding and controlling these parameters, significant improvements in CNT growth can be achieved. However, CNT growth is influenced by multiple interrelated factors, which complicates the identification of optimal conditions for each individual factor. These variables often interact and are not independent. In this research, we provide a comprehensive review of the critical factors affecting CNT growth to aid researchers in achieving more successful CNT synthesis. [ABSTRACT FROM AUTHOR]

Kombucha is a popular fermented beverage that involves fermentation using a symbiotic culture of bacteria and yeast (SCOBY) and produces bacterial cellulose (BC). Carbon and nitrogen sources are essential in kombucha processing and BC production. However, studies on cost-effective BC production as an alternative source of leather have remained scarce. This study aimed to assess the effects of various nitrogen and carbon sources on the production of kombucha BC, investigate the qualities, and dye the product using natural colorant. Different nitrogen sources (such as black tea, white tea, and green tea) and carbon sources (honey, sugar cane, palm sugar, and brown sugar) were used to produce kombucha BC, as well as to appraise the product qualities, which were dyed using three distinct natural dyes (coffee, ginger, and sappan wood). The results revealed that different nitrogen and carbon sources produced different BC with different properties. Green tea (N-source) and palm sugar (C-source) containing medium produced a BC thickness of 0.194 ± 0.04 mm with the highest tensile strength (24.42 ± 3.90 g). Different dyes also result in the fabric having different colors: brownish yellow (coffee), yellowish orange (ginger), and red (sappan wood). All BC products showed color stability after 8 months of storing at room temperature. In conclusion, effective BC production could use green tea and palm sugar as the best nitrogen and carbon sources, respectively. Dyed BC showed good visual quality and is promising for its eco-friendly and sustainable application in fashion products. [ABSTRACT FROM AUTHOR]

Invasive alien plants pose a great threat to local plants and ecosystems. How to effectively alleviate this hazard is an unresolved issue. This study explored the carbon release characteristics of an invasive plant Spartina alterniflora and evaluated the ability of nitrogen removal from shrimp culture wastewater through constructing seawater wetland. The results showed that fresh S. alterniflora had a significantly higher carbon release potential and bioavailability than that of withered S. alterniflora, and alkali-heat treatment could increase the carbon release with an average COD release rate of 33.39 mg/g from fresh S. alterniflora. The removal rate of total nitrogen was improved by about 22% in seawater constructed wetlands by adding fresh S. alterniflora biomass. Moreover, the addition of fresh S. alterniflora biomass was beneficial to the increase in the abundance of denitrification-related genera Vibrio, which might be the key to the improvement of nitrate removal efficiency in seawater constructed wetland systems. These findings indicated that invasive plants S. alterniflora as carbon sources of seawater wetland was a feasible and effective resource utilization strategy. [ABSTRACT FROM AUTHOR]

Aquaculture, a vital industry supplying a significant portion of the world's seafood, faces challenges such as the deterioration of the aquaculture environment. The objective of this study was to isolate and identify microorganisms with the capacity to eliminate nitrite in water from shrimp ponds and evaluate their potential as probiotics to improve water quality. Additionally, the study also determines the ideal conditions for the probiotic to effectively reduce nitrite-N and ammonia-N. Water samples were collected from four shrimp ponds (SW1, SW2, SW3, SW4) and isolates were obtained. Among all the samples, SW4 was the most effective in reducing the concentration of nitrite-N. Upon further isolation of SW4, the strain SW4-W6 showed significant nitrite-N reduction capabilities compared to the 19 other isolates tested. Through morphological, genetic (ITS sequence), and phylogenetic analyses, strain SW4-6 was identified as Candida sp. The isolation of Candida sp. SW4-6 showed superior nitrite-N and ammonia-N reduction capabilities, with sucrose as the carbon source and complete reduction observed at a C/N ratio of 15–20. Gene expression analysis revealed the up-regulation of nitrite reductase in SW4-6 after inoculation, with significantly higher expression observed with sucrose as the carbon source. Salinity and temperature significantly influenced nitrite-N and ammonia-N reduction by SW4-6, with higher temperatures (30 °C) and 0% NaCl favoring faster reduction rates. Candida sp. SW4-6 emerges as a promising probiotic candidate for aquaculture water quality management due to its efficient nitrite-N and ammonia-N reduction capabilities under optimal conditions. Its virulence profile and ability to thrive across various salinity and temperature conditions further support its potential applicability in aquaculture. [ABSTRACT FROM AUTHOR]

Background: Vitamin K2 is an essential nutrient for blood coagulation and cardiovascular health and mainly produced by bacteria strain like B. subtilis. researchers have explored producing strain improvement, cultivation mode, environmental optimization, increased secretion, and using cheaper carbon and nitrogen sources in order to increase vitamin K2 productivity. This study examines the impact of varioius concentration of soapstock, which is a by-product of vegetable oil refining, as an alternative carbon source with lower pirce, in the fermentation medium instead of glycerol on the microbial synthesis of vitamin K2 using B. subtilis natto ATCC 23857. Results: The results demonstrate that when the glycerol in fermentation medium was substituted with soapstock, by 75% concentartion, the fermentation process produced a yield of 158.16 mg/L of vitamin K2 after 72 h; This was 3.8 times more than the control medium containing glycerol. When the entire culture medium was replaced with wastewater, the vitamin K2 concentration reached 21.18 mg/L, 52% of the control medium’s concentration. If the carbon sources in the fermentation medium consisted of 20% soapstock and 47.4 g/L glycerol (maintaining the same final glycerol concentration as the control medium), the vitamin K2 concentration reached 35.7 mg/L or 85.8% of the control medium. The analysis of soapstock fermentation medium characteristics reveals that after fermentation with B. subtilis, the COD of soapstock fermentation medium was dramatically reduced from 259,500 mg/L to 57,830 mg/L. Conclusions: Using soapstock as an alternative carbon source for fermentation did not negatively impact the bioprocess and increased vitamin K2 production. Therefore, this research introduces an alternative carbon resource for vitamin K2 production and paves the way for the biorefinement of soapstock. [ABSTRACT FROM AUTHOR]

Nitrogen oxide (NOx) is an attractive nitrogen source. Electrocatalytic NOx reduction coupled with the conversion of carbon source molecules offers a potential route for sustainable synthesis of valuable nitrogenous organics. This review discusses recent progress on the synthesis of electrocatalytic organonitrogen compounds (such as oximes, amino acids, amines, amides and urea) via C−N coupling from NOx and carbon source. The electrocatalytic performance, catalyst structure and especially reaction mechanism are discussed. Current challenges, catalyst design principles, the understanding on reaction mechanisms, as well as possible strategies for improving reaction selectivity and activity are proposed, which will guide future researches in the electrocatalytic conversion of NOx and carbon source. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the effects of different concentrations of fructooligosaccharide (FOS) instead of glucose (GLU) as the carbon source in the biofloc system. GLU was used as the carbon source in the control group, and 2.5%, 5.0%, 7.5%, and 10.0% FOS were used instead of GLU as the carbon source in experimental groups. Ammonium chloride was used the nitrogen source with a C/N ratio of 15. Bacillus subtilis was supplemented to promote biofloc formation. The results showed that the concentrations of ammonia nitrogen, nitrite nitrogen, nitrate nitrogen, and total nitrogen were reduced effectively in all groups. High-throughput 16S rRNA sequencing revealed that the abundance of Flavobacterium was significantly increased in the 2.5% FOS group (P < 0.05), while Acinetobacter was significantly increased in the 10.0% FOS group on the 14th day (P < 0.05), the abundance of Aeromonadaceae was significantly reduced in all experimental groups (P < 0.05). Compared with the control group, the abundance of Aeromonadaceae was significantly decreased in 2.5% FOS on the 28th day (P < 0.05). Correlation analysis between microbial community composition and environmental factors indicated Flavobacterium and norank_f__norank_o__Saccharimonadales were negatively associated with three forms of nitrogen. In summary, the substitution of GLU with 2.5% FOS as the carbon source in the biofloc system significantly increased the abundance of core bacteria (Flavobacterium and Acinetobacter) and significantly reduced harmful bacteria (Aeromonadaceae), thereby stabilizing bacterial communities within the aquatic environment. The positive effects exhibited by 10.0% FOS were similar to 2.5% FOS. Based on experimental results and cost, the recommended proportion of FOS as a substitute for GLU is 2.5%. This research provides a foundation for the application of FOS as a carbon source in biofloc system and serves as a reference for future studies in this field. [ABSTRACT FROM AUTHOR]

The primary objective of this research is to evaluate the feasibility of two of the most prevalent agricultural residues in Ecuador, banana peels and pineapple peels, as a carbon source in the culture medium of Komagataeibacter hansenii for the production of bacterial cellulose (BC) and BC-based paper. This analysis includes an assessment of the productivity parameters of the obtained BC and the quality parameters of the BC-based paper, employing multivariate statistical methodologies. The experimental design consisted of fifteen treatments: T1 served as the control using the standard HS medium, while treatments T2–T8 used banana peel extracts (BPE), and treatments T9–T15 used pineapple peel extracts (PPE) at concentrations from 10% to 40% (v/v). Extracts were prepared with tailored pretreatments for each type of peel to optimize bioactive compound recovery. Standardized fermentation and purification conditions were applied, and once the cellulose was obtained, additives and coating agents were incorporated to produce paper samples from each treatment. The results indicated that higher BPE concentrations (T5, T6, T7, and T8) correlated significantly with increased Weight and Yield of BC, as well as improved grammage and water content in the BC-based paper. This highlights that efficient paper production is influenced by the quality of the bacterial cellulose used, with BPE-based media yielding optimal results due to their nutrient composition, which promotes bacterial growth and metabolic activity. This approach suggests a pathway for advancing sustainable and economical paper production. [ABSTRACT FROM AUTHOR]

【Objective】The effects of nitrogen, phosphorus, carbon and iron nutrients on the growth of Oocystis borgei were explored, and the optimal nutrient formula was selected to provide references for its efficient and large-scale cultivation.【Method】Single factor test was used to analyze the effects of different nitrogen, phosphorus, carbon and iron nutrients on the growth of O. borgei, to obtain the best nutrients and their respective concentrations. Orthogonal tests were conducted to optimize the factors that had a great impact on the the growth of O. borgei. Finally, the optimal nutrient formula was obtained.【Result】The results of the single factor test showed that the optimal sources and concentrations of nitrogen, phosphorus, carbon and iron sources for O. borgei were CO(NH2)2 160 mg/L, C3H7Na2O6P 8 mg/L, NaHCO3 1 g/L, and FeCl3 0.2 mg/L, respectively. The results of the orthogonal tests showed that the effect of each nutrient on the growth of O. borgei ranked as: phosphorus source > nitrogen source > carbon source, and phosphorus source had the most significant effect on the growth of O. borgei (P < 0.05). The optimal formula was: CO(NH2)2 120 mg/L, C3H7Na2O6P 12 mg/L and NaHCO3 2.5 g/L. Under the optimal condition, the algal cell density reached 22.07×106 cells/mL, which was 12 times higher than that before optimization (1.74×106 cells/mL).【Conclusion】The optimal nitrogen, phosphorus, carbon, and iron sources and concentrations for O. borgei were determined and the optimal nutrient formula was obtained by optimizing the conditions, which significantly increased the algal cell density.

【Objective】The Volvariella brumalis He sp.nav. is a unique low-temperature mushroom in China. The optimal conditions for the fermentation culture of liquid strains of V. brumalis were investigated, aiming to reduce the production time and costs of V. brumalis strains, and promote the standardized and large-scale production of V. brumalis.【Method】The optimal growth conditions of liquid fermentation culture of V. brumalis were studied from the aspects of carbon sources and nitrogen sources, temperature, pH, and inoculation amount. A four-factor and three-level orthogonal test was conducted to determine the best fermentation formula.【Result】The result showed that the optimal carbon source for liquid fermentation culture of V. brumalis was glucose. And the dry masses of the mycelial bulb was 1.35 g/L. The optimal nitrogen source was fermented soybean meal powder, and the dry masses of the mycelial bulb was 3.76 g/L. Suitable carbon sources (glucose, fructose) and nitrogen sources (fermented soybean meal powder, fermented corn pulp) were selected to establish L9 (34) orthogonal table for four-factor and three-level orthogonal tests to obtain the optimal formula for fermentation culture: glucose 20.0 g, fructose 10.0 g, fermented soybean meal powder 2.5 g, fermented corn syrup 2.5 g, KH2PO4 1 g, K2HPO4 0.5 g, MgSO4·7H2O 0.5 g, vitamin B1 10 mg, pH of 6-7, H2O 1000 mL. The mycelial bulb dry mass reached 5.79 g/L with this formula, and the inoculation amount was 3% when cultured at 18 ℃ and 120 r/min for 15 d. Other culture conditions were explored with an optimized formulation, obtaining an optimum temperature of 18℃, a mycelial bulb dry mass of 5.97 g/L, and an appropriate pH from 6 to 7. And when the inoculation amount reached 7%, the dry mass of the mycelial bulb was 6.31 g/L.【Conclusion】When the inoculation amount was 7%, the dry mass of the mycelial bulb was 6.31 g/L after 15 days of culture, which could be directly used in the next step of production and greatly shortened the seed production cycle of V. brumalis.

Under the background of “dual carbon”, sewage treatment not only needs to achieve resource utilization, but also needs to reduce carbon emissions. To reduce N2O emissions, scholars at home and abroad have conducted extensive research on N2O emissions from urban sewage plants. Firstly, it was summarized that both nitrification and denitrification processes in wastewater treatment produce N2O. The mechanism and mode of N2O production during the reaction process also differ, and the amount of N2O produced may vary depending on the process. Secondly, three typical biological denitrification processes for wastewater were reviewed: cyclic activated sludge system (CASS) process, anaerobic ammonium oxidation ( ANAMMOX) process, and nitrosation anaerobic ammonium oxidation (CANON) process, as well as four factors affecting N2O emissions from urban wastewater treatment plants: carbon source, dissolved oxygen concentration, temperature, and magnetic field strength. Finally, the shortcomings of current research were summarized and provided prospects from four aspects: temperature influencing conditions, carbon source types, CANON process mechanisms, and N2O recovery and utilization. The CANON process is effective for removing N2O, but it should be noted that a low pH in the reaction can cause NH2OH and HNO2 to react and produce N2O, thereby weakening the removal effect. [ABSTRACT FROM AUTHOR]

Copyright of Acta Agriculturae Zhejiangensis is the property of Acta Agriculturae Zhejiangensis Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Nitrogen (N) availability limits plant growth and soil carbon (C) sequestration in N‐limited ecosystems, however, plant and soil C feedback on the free‐living nitrogen fixation (FLNF) process is poorly understood. Moreover, whether this feedback is influenced by initial N availability in leguminous and non‐leguminous forest soils has not been clarified. Here, we found that the addition of plant‐ and microbial‐derived C significantly enhanced soil nitrogenase activity (13∼28%) and that microbial‐derived C had a more positive impact. These positive effects were attributed to the direct C‐energy supply (0.49∼0.84) rather than variations in soil microbial activity (−0.01∼0.21) and substrate resources (−0.45∼0.27). Long‐term N addition did not inhibit FLNF. C addition promoted FLNF in soils of the two forests, but the response rate was higher in the leguminous forest soils. Our study reveals that increased soil C availability can drive FLNF in tropical forests, enhancing our understanding of the soil C‐N coupling mechanism. Plain Language Summary: Explicit consideration of controlling factors for free‐living nitrogen fixation (an important process of nitrogen biogeochemistry), is critical to understanding the response of ecosystems to environmental change. Our study reveals a previously overlooked but important process in which increased soil carbon availability exerts positive feedback on soil nitrogen inputs via free‐living nitrogen fixation. This insight enhances our understanding of soil carbon‐nitrogen coupling mechanisms and highlights an important nitrogen source in tropical forests based on increased vegetation and soil carbon sink conditions under global environmental change scenario. Key Points: Carbon (C) input affected free‐living nitrogen fixation (FLNF) more than nitrogen (N) application in tropical forest soilsBoth plant‐ and microbial‐derived C enhanced FLNF, but microbial‐derived C had a more positive impactC addition promoted FLNF in soils of the two forests, but the response rate was higher in the leguminous forest soils [ABSTRACT FROM AUTHOR]

Despite the long research history on the genus Coelastrella, its species diversity and biotechnological potential have not been fully explored. For the first time, cluster analysis of morphological characteristics was done in the representatives of the said genus. The results obtained have shown that morphological similarity does not necessarily indicate a molecular genetic relationship. It the light of it, the taxonomic status of species can reliably be determined using specific DNA region, such as 18S–ITS1–5.8S–ITS2. The V4 and V9 regions of gene 18S rRNA are relatively conservative fragments which are not suitable for species identification. The ITS2 can be used as a "short barcode". Among the advanced machine methods for delimitation species, the most effective algorithm for distinguishing Coelastrella species was the Generalized Mixed Yule Coalescent (GMYC) method. This paper represented for the first time our comprehensive review of the works devoted to the analysis of the biotechnological potential of representatives of the genus Coelastrella and shows that fatty acid composition of the three main chemogroups within the studied genus differs. In the future, this may form the basis for predicting the composition of the fatty acid profile of new strains, which is important while searching for organisms with specified biotechnological properties. In conclusion, an integrative approach was employed to describe Coelastrella affinis sp. nov., a new species of the genus Coelastrella with high biotechnological potential. Also, a new description of C. thermophila var. astaxanthina comb. nov. was proposed. [ABSTRACT FROM AUTHOR]

Biofloc technology is instrumental in improving growth performance and yield in shellfish aquaculture, while leading to enhanced water quality through maintaining the nutrients level within a safe range. More specifically, toxic nitrogenous wastes are converted into beneficial microbial biomass known as "biofloc", contributing to improve shellfish immune system. Among the various parameters affecting the efficiency of the process is the carbon source and C:N ratio. In light of these, the present work critically reviews the effects of biofloc systems on growth performance, immunity and diseases resistance in shellfish production. Moreover, it scrutinizes the microbial diversity and nutritional composition of biofloc. Then, the application of the technology in various shellfish cultures, including shrimp, freshwater prawn, crabs, crayfish, clam, and oyster, is presented. Overall, biofloc systems contribute to enhanced shellfish survival rate to the highest value of 96–100% for marine shrimp, 95–99% for freshwater prawn, 70–83% for crayfish, 83–100% for oyster, Crassostrea sp. and up to 2% for mud crabs larvae through substantially reducing the ammonia level in the culture (summarized in Table 1 – Table 5). Finally, the main challenges in utilizing biofloc systems, i.e., suitable aeration and mixing and microbial mechanisms involved are also explained to shed light on future research directions in the field. [ABSTRACT FROM AUTHOR]

Copyright of Guangdong Agricultural Sciences is the property of South China Agricultural University, Guangdong Academy of Agricultural Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Guangdong Agricultural Sciences is the property of South China Agricultural University, Guangdong Academy of Agricultural Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of East China University of Science & Technology is the property of Journal of East China University of Science & Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Carotenoids produced by bacteria, yeasts, algae and plants inactivate Free Radicals (FR). However, FR may inactivate carotenoids and even turn them into free radicals. Oxidative metabolism is a source of the highly motile Reactive Oxygen Species (ROS). To evaluate carotenoid interactions with ROS, the yeast Rhodotorula mucilaginosa was grown in dextrose (YPD), a fermentative substrate where low rates of oxygen consumption and low carotenoid expression were observed, or in lactate (YPLac), a mitochondrial oxidative-phosphorylation (OxPhos) substrate, which supports high respiratory activity and carotenoid production. ROS were high in YPLac-grown cells and these were unmasked by the carotenoid production-inhibitor diphenylamine (DPA). In contrast, in YPDgrown cells ROS were almost absent. It is proposed that YPLac cells are under oxidative stress. In addition, YPLac-grown cells were more sensitive than YPDgrown cells to menadione (MD), a FR-releasing agent. To test whether carotenoids from cells grown in YPLac had been modified by ROS, carotenoids from each, YPD- and YPLac-grown cells were isolated and added back to cells, evaluating protection from MD. Remarkably, carotenoids extracted from cells grown in YPLac medium inhibited growth, while in contrast extracts from YPDgrown cells were innocuous or mildly protective. Results suggest that carotenoid-synthesis in YPLac-cells is a response to OxPhos-produced ROS. However, upon reacting with FR, carotenoids themselves may be inactivated or even become prooxidant themselves. [ABSTRACT FROM AUTHOR]

The failure of mass production of Spirulina plateaus can be attributed to an imbalance of nutrients (C:N) and an increase in accumulated sodium ions, coupled with the traditional harvesting process. The current study aims at the recovery of stressed and red cultures of Spirulina platensis as well as enhanced phycocyanin accumulation. The stressed Spirulina platensis cultures were obtained from a local Egyptian Spirulina production farms, which were further subjected to water analyses after removing the Spirulina biomass. Optimization was performed within 300-ml water path photobioreactor. Spirulina platensis samples were incubated with Zarrouk medium comparing with those modified using ammonium bicarbonate or ammonium acetate instead of sodium bicarbonate. Continuous batching was performed every 12 days during three sequenced batches. Growth measurements (dry weight and pigments) were performed along the incubation time. It was found that carbon content of the growth medium seems to be more effective in Spirulina growth and biomass characteristics. Under different carbon sources, acetate resulted in the maximum dry weight of 1.48 g·l−1 and recovery percentage of 463.3%. Such effect was extended along the different incubation batches. Various carbon concentrations revealed that moderate concentration of carbon in the form of acetate (0.699 g·l−1) leads to the maximum growth under the same nitrogen content. A similar trend was observed with chlorophyll and phycocyanin accumulation, while carotenoids showed the opposite manner. [ABSTRACT FROM AUTHOR]