Inhibitory effect of oil and fat on denitrification using food waste fermentation liquid as carbon source

Background: Tryptamine, a biogenic monoamine that is present in trace levels in the mammalian central nervous system, has probable roles as a neurotransmitter and/or a neuromodulator and may be associated with various neuropsychiatric disorders. One of the ways tryptamine may affect the body is by the competitive inhibition of the attachment of tryptophan to tryptophanyl tRNA synthetases. Methods: This study has explored the effects of tryptamine on growth of six yeast species (Saccharomyces cerevisiae, Candida glabrata, C. krusei, C. dubliniensis, C. tropicalis and C. lusitaniae) in media with glucose or ethanol as the carbon source, as well as recovery of growth inhibition by the addition of tryptophan. Results: Tryptamine was found to have an inhibitory effect on respiratory growth of all yeast species when grown with ethanol as the carbon source. Tryptamine also inhibited fermentative growth of Saccharomyces cerevisiae, C. krusei and C. tropicalis with glucose as the carbon source. In most cases the inhibitory effects were reduced by added tryptophan. Conclusion: The results obtained in this study are consistent with tryptamine competing with tryptophan to bind mitochondrial and cytoplasmic tryptophanyl tRNA synthetases in yeast: effects on mitochondrial and cytoplasmic protein synthesis can be studied as a function of growth with glucose or ethanol as a carbon source. Of the yeast species tested, there is variation in the sensitivity to tryptamine and the rescue by tryptophan. The current study suggests appropriate yeast strains and approaches for further studies.

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Enhancing denitrification efficiency for nitrogen removal using waste sludge alkaline fermentation liquid as external carbon source

Environmental Science and Pollution Research ◽

10.1007/s11356-018-3944-4 ◽

2018 ◽

Vol 26 (5) ◽

pp. 4633-4644 ◽

Cited By ~ 10

Author(s):

Mengyu Shao ◽

Liang Guo ◽

Zonglian She ◽

Mengchun Gao ◽

Yangguo Zhao ◽

...

Keyword(s):

Carbon Source ◽

Nitrogen Removal ◽

Waste Sludge ◽

External Carbon Source ◽

Fermentation Liquid

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Isolation and Characterization of a Novel p,p’-DDT-Degrading Bacterium: Aeromonas sp. Strain MY1 from Agricultural Soil

Asian Journal of Biotechnology and Bioresource Technology ◽

10.9734/ajb2t/2020/v6i430086 ◽

2020 ◽

pp. 12-22

Author(s):

Y. Murtala ◽

B. C. Nwanguma ◽

L. U. S. Ezeanyika

Keyword(s):

Carbon Source ◽

16S Rrna ◽

Agricultural Soil ◽

Sole Carbon Source ◽

Phylogenetic Analyses ◽

Inhibitory Effect ◽

Aerobic Conditions ◽

Degrading Bacterium ◽

Isolation And Characterization

Background: Despite the banned on the use of dichlorodiphenyltrichloroethane (DDT) and other Persistent Organic Pollutants (POPs) by the Stockholm Convention for their toxicity, emerging shreds of evidence have indicated that DDT is, however, still in use in developing countries. This might increase the global burden of DDT contamination and its hazardous effects. Aim: This study focused on the isolation and characterization of p,p’-DDT-degrading bacterium from a tropical agricultural soil. Methodology: Standard isolation procedure was used for the screening and isolation of the strain. The 16S rRNA and phylogenetic analyses were used to identify the isolate and established protocols were followed to characterize the strain. Results: A new strain belonging to the genus Aeromonas was isolated from agricultural soil using minimal salt-p,p’-DDT enrichment medium. The 16S rRNA sequencing was used to identify the strain and the partial sequence was deposited in the NCBI GenBank as Aeromonas sp. Strain MY1. This mesophilic isolate was capable of utilizing up to 50 mgL-1 of p,p’-DDT as the sole carbon source at an optimum pH of 7.5 and optimum temperature of 35 °C within 120 h under aerobic conditions. Fe2+ (0.2 mgL-1) demonstrated a stimulatory effect on the p,p’-DDT degradation capacity by the strain MY1. However, Zn, Cu, Pb, Hg, Ag and Cr ions have demonstrated various patterns of inhibitory effect on the p,p’-DDT degradation capacity of the isolate at 0.2 mgL-1. The strain MY1 could be a promising candidate for the bioremediation of p,p’-DDT contaminant. Conclusion: Aeromonas sp. strain MY1 was capable of utilizing p,p’-DDT as a sole carbon source under aerobic conditions. The utilization capacity of the strain was influenced by some heavy metals. Fe was found to enhance the p,p’-DDT utilization capacity of the isolate at a lower concentration. While Zn, Cu, Pb, Hg, Ag and Cr showed various patterns of inhibitory effect.

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Simultaneous Denitrification and Bio-Methanol Production for Sustainable Operation of Biogas Plants

Sustainability ◽

10.3390/su11236658 ◽

2019 ◽

Vol 11 (23) ◽

pp. 6658 ◽

Cited By ~ 1

Author(s):

I-Tae Kim

Keyword(s):

Wastewater Treatment ◽

Carbon Source ◽

Food Waste ◽

Treatment Process ◽

Wastewater Treatment Plants ◽

Treatment Efficiency ◽

Wastewater Treatment Process ◽

Methanol Production ◽

Sustainable Operation ◽

Biogas Plants

This study was conducted to secure the sustainability of biogas plants for generating resources from food waste (FW) leachates, which are prohibited from marine dumping and have been obligated to be completely treated on land since 2013 in South Korea. The aim of this study is to reduce the nitrogen load of the treatment process while producing bio-methanol using digested FW leachate diverted into wastewater treatment plants. By using biogas in conditions where methylobacter (M. marinus 88.2%) with strong tolerance to highly chlorinated FW leachate dominated, 3.82 mM of methanol production and 56.1% of total nitrogen (TN) removal were possible. Therefore, the proposed method can contribute to improving the treatment efficiency by accommodating twice the current carried-in FW leachate amount based on TN or by significantly reducing the nitrogen load in the subsequent wastewater treatment process. Moreover, the produced methanol can be an effective alternative for carbon source supply for denitrification in the subsequent process.

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