Integrated nutrient recycling: Ammonia recovery from thermophilic composting of shrimp aquaculture sludge via self-heated bench-scale reactor and mango plant growth enhancement by the compost.

Due to the rapid growth of the aquaculture industry, large amounts of organic waste are released into nature and polluted the environment. Traditional organic waste treatment such as composting is a time-consuming process that retains the ammonia (NH) in the compost, and the compost produced has little economic value as organic fertilizer. Illegal direct discharge into the environment is therefore widespread.

The effect of calcium hydroxide addition on enhancing ammonia recovery during thermophilic composting in a self-heated pilot-scale reactor.

A modified outdoor large-scale nutrient recycling system was developed to compost organic sludge and aimed to recover clean nitrogen for the cultivation of high-value-added microalgae. This study investigated the effect of calcium hydroxide addition on enhancing NH recovery in a pilot-scale reactor self-heated by metabolic heat of microorganisms during thermophilic composting of dewatered cow dung. 350 kg-ww of compost was prepared at the ratio of 5: 14: 1 (dewatered cowdung: rice husk: compost-seed) in a 4 m cylindrical rotary drum composting reactor for 14 days of aerated composting.

Effect of oxygen deficiency on organic matter decomposition during the early stage of composting.

This study aimed to elucidate the recovery of organic matter decomposition after oxygen deficiency in the early stage was replaced by aerobic conditions during composting. Oxygen deficiency at the early stage was created by supplying nitrogen gas into the composting for 3 days (LN3dA) and 5 days (LN5dA). Subsequently, air was introduced until the end of composting instead of nitrogen gas.

Complexity of acclimatization substrate affects anaerobic digester microbial community response to organic load shocks.

This study elucidated the changes in the short-term response to organic load shocks of the anaerobic digestion (AD) microbiome acclimatized to a simple substrate and a complex substrate. Batch vial reactors were inoculated with AD sludge acclimatized to either a simple (starch and hipolypeptone) or a complex (dog food and starch) substrate, both with carbon-to-nitrogen ratio of 25. Organic loads in the form of an easily degradable substrate mix (starch and hipolypeptone) with concentrations varying from 0 to 5 g VS/L were applied to the reactors.

Effects of oxygen supply rate on organic matter decomposition and microbial communities during composting in a controlled lab-scale composting system.

The study aimed to elucidate the effect of oxygen supply rate (OSR) on the composting of model organic waste independently from other factors by using a controlled laboratory-scale reactor system. Four OSRs, 96.2, 24.

Co-occurrence network analysis reveals loss of microbial interactions in anaerobic digester subjected to repeated organic load shocks.

Fluctuations in the anaerobic digestion (AD) organic loading rate (OLR) cause shocks to the AD microbiome, which lead to unstable methane productivity. Managing these fluctuations requires a larger digester, which is impractical for community-scale applications, limiting the potential of AD in advancing a circular economy. To allow operation of small-scale AD while managing OLR fluctuations, we need to tackle the issue through elucidation of the microbial community dynamics via 16S rRNA gene sequencing.

Effect of hydrothermal treatment on organic matter degradation, phytotoxicity, and microbial communities in model food waste composting.

Hydrothermal treatment (HTT) as a pretreatment method for compost raw material has multiple benefits such as enhanced solubility of organic material, improved bioaugmentation, and reduced biohazard by killing harmful microorganisms. In this study, we pretreated food waste via HTT at 180 °C for 30 min to investigate its effect on food waste composting. HTT generated 8.

Short-term changes in the anaerobic digestion microbiome and biochemical pathways with changes in organic load.

Fluctuations in organic loading rate are frequently experienced in practical-scale anaerobic digestion systems. These impose shocks to the microbiome leading to process instability and failure. This study elucidated the short-term changes in biochemical pathways and the contributions of microbial groups involved in anaerobic digestion with varying organic load shocks.

Effect of enzymatic pre-treatment on thermophilic composting of shrimp pond sludge to improve ammonia recovery.

In recent years, attempts have been made to develop a thermophilic composting process for organic sludge to produce ammonia gas for high value-added algal production. However, the hydrolysis of non-dissolved organic nitrogen in sludge is a bottleneck for ammonia conversion. The aim of this study was to identify enzymes that enhance sludge hydrolysis in a thermophilic composting system for ammonia recovery from shrimp pond sludge.

Inoculation of Neurospora sp. for improving ammonia production during thermophilic composting of organic sludge.

Recent attempts have been made to develop a thermophilic composting process for organic sludge to not only produce organic fertilizers and soil conditioners, but to also utilize the generated ammonia gas to produce high value-added algae. The hydrolysis of organic nitrogen in sludge is a bottleneck in ammonia conversion, and its improvement is a major challenge. The present study aimed to elucidate the effects of inoculated Neurospora sp.

Tolerance of to High Ammonium Nitrogen and Its Effect on Growth Rate, Carotenoid, and Fatty Acids Productivity.

Microalgae can use either ammonium or nitrate for its growth and vitality. However, at a certain level of concentration, ammonium nitrogen exhibits toxicity which consequently can inhibit microalgae productivity. Therefore, this study is aimed to investigate the tolerance of to high ammonium nitrogen concentrations and its effects on growth rate, photosynthetic efficiency ( ), pigment contents (chlorophyll , lutein, neoxanthin, and β-carotene), and fatty acids production.

Changes in the microbial community during the acclimation process of anaerobic digestion for treatment of synthetic lipid-rich wastewater.

Changes in the microbial community were investigated during the acclimation process of anaerobic digestion while treating synthetic lipid-rich wastewater, which comprised of glucose, acetic acid, lactic acid, and soybean oil. The oil content in the synthetic wastewater was increased successively from 0% to 25% and finally to 50% of the total carbon content, to clarify the effect of substrate type change from easily degradable organic materials to lipid. The oil decomposition-associated methane production rate increased as the microorganisms acclimated to the oil and eventually levelled off around 0.

Characterizing the microbial community involved in anaerobic digestion of lipid-rich wastewater to produce methane gas.

This study attempted to characterize the microbial community and its role in anaerobic digestion of lipid. Reactors were fed semi-continuously with three related substrates, oil and its degradation intermediates (glycerol and long chain fatty acids (LCFAs)), with a stepwise increase in organic loading rate for 90 days. Microbial community analysis using next-generation sequencing (NGS) with the MiSeq Illumina platform revealed that Anaerolineaceae was the most dominant group of bacteria in all experiments, whereas Clostridium, Desulfovibrio, Rikenellaceae, and Treponema were observed characteristically in glycerol degradation and Leptospirales, Synergistaceae, Thermobaculaceae and Syntrophaceae were seen with high abundance in LCFA and oil mineralization.

Lactic acid bacteria modulate organic acid production during early stages of food waste composting.

Lactic acid bacteria are observed during early stages of almost all food waste composting. Among them, 2 types of lactic acid bacteria, Pediococcus (homofermentative lactic acid bacterium) and Weissella (heterofermentative lactic acid bacterium) have been often reported. In this study, the roles of these 2 types of lactic acid bacteria in the composting were tried to elucidate.

Effect of Ca(OH) dosing on thermophilic composting of anaerobic sludge to improve the NH recovery.

The primary biological treatment method for organic sludge is composting and/or anaerobic digestion, but their product (compost or biogas) is of little economic benefit; therefore, an improved process to produce a high-value product is required to make sludge management more sustainable. Maximizing NH gas recovery during composting processes has the potential benefit of producing high-value microalgal biomass. However, the majority of produced ammonia does not evaporate as NH gas but retains as NH-N in the compost after fermentation.

Enhanced fermentative hydrogen production from industrial wastewater using mixed culture bacteria incorporated with iron, nickel, and zinc-based nanoparticles.

The present study assessed the efficiency of utilizing mixed culture bacteria (MCB) incorporated with individual nanoparticles (NPs), i.e., hematite (α-FeO), nickel oxide (NiO), and zinc oxide (ZnO), dual NPs (α-FeO + NiO, α-FeO + ZnO, and NiO + ZnO), and multi-NPs (α-FeO + NiO + ZnO) for hydrogen production (HP) from industrial wastewater containing mono-ethylene glycol (MEG).

Effect of temperature on thermophilic composting of aquaculture sludge: NH recovery, nitrogen mass balance, and microbial community dynamics.

Development of thermophilic composting for maximizing NH gas recovery would enable the production of a nitrogen source which is free from pathogen/heavy metal, for the cultivation of high-value microalgae. The present study examined the effect of NH recovery, nitrogen mass balance, and microbial community dynamics on thermophilic composting of shrimp aquaculture sludge. The emission of NH gas at 60 and 70 °C was 14.

Application of Bacillus sp. TAT105 to reduce ammonia emissions during pilot-scale composting of swine manure.

Thermophilic ammonium-tolerant bacterium Bacillus sp. TAT105 grows and reduces ammonia (NH) emissions by assimilating ammonium nitrogen during composting of swine feces. To evaluate the efficacy of a biological additive containing TAT105 at reducing NH emissions, composting tests of swine manure on a pilot scale (1.

Temperature control strategy to enhance the activity of yeast inoculated into compost raw material for accelerated composting.

The effects of inoculating the mesophilic yeast Pichia kudriavzevii RB1, which is able to degrade organic acids, on organic matter degradation in composting were elucidated. When model food waste with high carbohydrate content (C/N=22.3) was used, fluctuation in the inoculated yeast cell density was observed, as well as fluctuation in the composting temperature until day 5 when the temperature rose to 60°C, which is lethal for the yeast.

Direct production of ethanol from neoagarobiose using recombinant yeast that secretes α-neoagarooligosaccharide hydrolase.

An α-neoagarooligosaccharide hydrolase, AgaNash, was purified from Cellvibrio sp. OA-2007, which utilizes agarose as a substrate. The agaNash gene, which encodes AgaNash, was obtained by comparing the N-terminal amino acid sequence of AgaNash with that deduced from the nucleotide sequence of the full-length OA-2007 genome.

Utilization of Bacillus sp. strain TAT105 as a biological additive to reduce ammonia emissions during composting of swine feces.

Bacillus sp. strain TAT105 is a thermophilic, ammonium-tolerant bacterium that grows assimilating ammonium nitrogen and reduces ammonia emission during composting of swine feces. To develop a practical use of TAT105, a dried solid culture of TAT105 (5.

Draft Genome Sequence of the Nonmarine Agarolytic Bacterium Cellvibrio sp. OA-2007.

Cellvibrio sp. OA-2007 is a Gram-negative, aerobic, and agarolytic bacterium isolated from activated sludge. We present the draft genome sequence of strain OA-2007, composed of 97 contigs, totaling 4,595,379 bp in size, and containing 4,094 open reading frames, with a G+C content of 47.

Composting of food waste subjected to hydrothermal pretreatment and inoculated with Paecilomyces sp. FA13.

Food waste collected from restaurants, convenience stores, and food-processing factories was mixed with sawdust and subjected to hydrothermal pretreatment at 180°C for 30min to prepare compost raw material. Furan compounds such as 5-HMF (5-hydroxymethyl furfural) and furfural were produced at concentration levels of approximately 8 and 0.5mg/g-ds, respectively, through hydrothermal pretreatment.

A novel colorimetric method for the detection of Escherichia coli using cytochrome c peroxidase-encoding bacteriophage.

A new rapid and simple method was developed for the detection of Escherichia coli by constructing a recombinant T4 phage carrying the cytochrome c peroxidase gene derived from Saccharomyces cerevisiae (T4ccp) using which, the colorimetric detection of E. coli K12 was examined. The oxidation activity toward the chromogenic substrate cytochrome c was demonstrated by the cytochrome c peroxidase (CCP) produced from the T4ccp genome.

Purification and characterization of α-neoagarooligosaccharide hydrolase from Cellvibrio sp. OA-2007.

α-Neoagarooligosaccharide (α-NAOS) hydrolase was purified from Cellvibrio sp. OA-2007 by using chromatographic techniques after hydroxyapatite adsorption. The molecular masses of α-NAOS hydrolase estimated using SDS-PAGE and gel filtration chromatography were 40 and 93 kDa, respectively, and the optimal temperature and pH for the enzyme activity were 32ºC and 7.