Methanogenesis inhibition by phosphorus in anaerobic liquid waste treatment

2017 ◽  
Vol 2 (1) ◽  
pp. 1-8 ◽  
Author(s):  
D. C. Mancipe-Jiménez ◽  
C. Costa ◽  
M. C. Márquez
Keyword(s):  
Bacterial Growth ◽  
Volatile Fatty Acids ◽  
Waste Treatment ◽  
Liquid Waste ◽  
Gas Production ◽  
Phosphorus Concentration ◽  
Concentration Increase ◽  
Electron Microscopic ◽  
Bacterial Growth Rate ◽  
Filamentous Microorganisms

Abstract The effect of a sudden influent phosphorus concentration increase on a completely mixed reactor of an anaerobic liquid waste treatment process was evaluated. Chemical oxygen demand (COD), volatile fatty acids (VFA), suspended solids, pH and gas production were measured for process monitoring. Optical and scanning electron microscopic observations were also performed. Kinetic parameters were estimated from substrate and microorganisms concentrations, mass balances and experimental data. After phosphorus concentration increase, VFA concentration enhanced by 500% approximately and COD removal, gas production, bacterial growth coefficient (Y) and maximum bacterial growth rate (μmax) decreased 20%, 18%, 54% and 35% respectively. An excessive growth of filamentous microorganisms was also observed. The equilibrium established between acidogenic and methanogenic microorganisms was visibly affected causing a decrease of methanogenic activity. The experimental results showed that phosphorous arises as a methanogenesis inhibitor and a growth factor for filamentous microorganism under anaerobic conditions.

scholarly journals The relationship between rumen bacterial growth, intake of dry matter, digestible organic matter and volatile fatty acid production in buffalo (Bos bubalis) calves

1977 ◽  
Vol 38 (3) ◽  
pp. 335-340 ◽  
Author(s):  
U. B. Singh ◽  
D. N. Verma ◽  
A. Varma ◽  
S. K. Ranjhan
Keyword(s):  
Organic Matter ◽  
Bacterial Growth ◽  
Dry Matter ◽  
Volatile Fatty Acids ◽  
Turnover Time ◽  
Regression Equations ◽  
Production Rates ◽  
Bacterial Growth Rate ◽  
Fatty Acid Production ◽  
Digestible Organic Matter

1. The production rates of bacteria in the rumen of buffalo (Bos bubalis) calves were estimated using an isotope-dilution technique. A series of fifteen experiments was done with animals given green maize and nine experiments with animals given cowpea (Vigna unguiculata).2. The turnover time ranged from 205 to 567 min in the group given green maize and from 330 to 648 min in animals offered cowpea. The production rates of bacteria were (mean±SE; g/d) 145.77±7.240 and 237.09±11.847 in animals given green maize and cowpea respectively.3. There was a significant correlation between bacterial production rates and dry matter intake, digestible organic matter and total volatile fatty acids formed in the rumen.4. Regression equations obtained for the two foodstuffs were different suggesting that the bacterial growth rate may vary depending upon the quantity and quality of foodstuff digested and possibly the ratio nitrogen: energy of the foodstuff.

Exhibition of novel photocatalytic activity and photoluminescence properties with high inhibition towards bacterial growth by hydrothermally grown ZnO nanorods

2020 ◽  
Vol 16 ◽  
Author(s):  
Nihar Ranjan Panda ◽  
Dojalisa Sahu
Keyword(s):  
Methylene Blue ◽  
Bacterial Growth ◽  
Organic Dyes ◽  
Zno Nanorods ◽  
Antibacterial Properties ◽  
Crystallographic Structure ◽  
Inhibition Activity ◽  
Electron Microscopic ◽  
Skin Bacteria ◽  
High Inhibition

Background: Metal oxide nanomaterial such as; ZnO shows novel structural, optical, electrical and antibacterial properties due to wide band gap (3.37 eV) and high excitonic binding energy (60 meV). Probing these inherent properties of nanosized ZnO with different morphology has generated new interest among researchers Objective: To investigate the size dependent functional attributes, ZnO nanorods were prepared by hydrothermal method and the photocatalytic (PC) efficiency was studied. The photoluminescence (PL) property of ZnO nanorods was also studied by recording the emission spectrum under photo-excitation. These nanorods (NRs) were coated on cotton fabric to study the effectiveness of these NRs in defending and inhibiting the growth of different bacteria Methods: The crystallographic structure and morphology of the ZnO samples were investigated by X-ray diffraction (XRD) and field emission scanning electron microscopic (FESEM) measurements. PL measurement at room temperature was undertaken by exciting the sample with light of wavelength 350 nm. The PC property of ZnO NRs was studied in degrading organic dyes like methylene blue. Bacteria like Staphylococcus aureus, Escherichia coli and Bacillus subtilis were cultured and the inhibition of growth of these bacteria was studied by the application of ZnO. To enhance the microbe defence mechanism of fabric, we coated these NRs on fabric test samples and investigated the bacterial growth on it. Results: XRD and FESEM studies reveal the dimension of the synthesized products in nano range. These nanorods are of high density and surface roughness as per the FESEM study. PL measurement shows the presence of strong UV emission at 382 nm with defect emissions in the blue-green region opening up the path for ZnO to be used in fabrication of optoelectronic devices. PC study reveals that 89% degradation of methylene blue (MB) dye is achievable in 180 min using these ZnO catalysts. The anti-bacterial study shows that the minimum inhibitory concentration (MIC) of ZnO nanorods coated on the fabric against S. aureus is found to be 3.5 mg/ml which is the minimum as compared to E. coli (7.5 mg/ml) and B. subtilis (5.5 mg/ml). The study further enunciates that fabric coated with ZnO samples exhibited considerably high inhibition activity toward S. aureus. Conclusion: The study shows that ZnO NRs can be effectively used for fabrication of UV-LASER/LED. Photocatalytic efficiency of ZnO will be useful for degradation of organic dyes controlling environment pollution. It further enunciates that fabric coated with ZnO samples exhibited considerably high inhibition activity toward S. aureus (skin bacteria) which will be helpful in defending microbes if used in surgical cotton bandages

scholarly journals Pilot Study of the Effects of Polyphenols from Chestnut Involucre on Methane Production, Volatile Fatty Acids, and Ammonia Concentration during In Vitro Rumen Fermentation

Animals ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 108
Author(s):  
Yichong Wang ◽  
Sijiong Yu ◽  
Yang Li ◽  
Shuang Zhang ◽  
Xiaolong Qi ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Acetic Acid ◽  
Propionic Acid ◽  
Acid Content ◽  
Volatile Fatty Acids ◽  
Rumen Fermentation ◽  
Gas Production ◽  
Quadratic Response ◽  
In Vitro Rumen Fermentation

Nutritional strategies can be employed to mitigate greenhouse emissions from ruminants. This article investigates the effects of polyphenols extracted from the involucres of Castanea mollissima Blume (PICB) on in vitro rumen fermentation. Three healthy Angus bulls (350 ± 50 kg), with permanent rumen fistula, were used as the donors of rumen fluids. A basic diet was supplemented with five doses of PICB (0%–0.5% dry matter (DM)), replicated thrice for each dose. Volatile fatty acids (VFAs), ammonia nitrogen concentration (NH3-N), and methane (CH4) yield were measured after 24 h of in vitro fermentation, and gas production was monitored for 96 h. The trial was carried out over three runs. The results showed that the addition of PICB significantly reduced NH3-N (p < 0.05) compared to control. The 0.1%–0.4% PICB significantly decreased acetic acid content (p < 0.05). Addition of 0.2% and 0.3% PICB significantly increased the propionic acid content (p < 0.05) and reduced the acetic acid/propionic acid ratio, CH4 content, and yield (p < 0.05). A highly significant quadratic response was shown, with increasing PICB levels for all the parameters abovementioned (p < 0.01). The increases in PICB concentration resulted in a highly significant linear and quadratic response by 96-h dynamic fermentation parameters (p < 0.01). Our results indicate that 0.2% PICB had the best effect on in-vitro rumen fermentation efficiency and reduced greenhouse gas production.

scholarly journals Simplified Approach to Predict Food Safety through the Maximum Specific Bacterial Growth Rate as Function of Extrinsic and Intrinsic Parameters

2021 ◽  
Vol 5 (2) ◽  
pp. 22
Author(s):  
Pedro D. Gaspar ◽  
Joel Alves ◽  
Pedro Pinto
Keyword(s):  
Growth Rate ◽  
Food Safety ◽  
Information And Communication Technologies ◽  
Bacterial Growth ◽  
Low Cost ◽  
Extrinsic Factors ◽  
Bacterial Growth Rate ◽  
Modeling Tools ◽  
Simplified Approach ◽  
Food Safety And Quality

Currently, we assist the emergence of sensors and low-cost information and communication technologies applied to food products, in order to improve food safety and quality along the food chain. Thus, it is relevant to implement predictive mathematical modeling tools in order to predict changes in the food quality and allow decision-making for expiration dates. To perform that, the Baranyi and Roberts model and the online tool Combined Database for Predictive Microbiology (Combase) were used to determine the factors that define the growth of different bacteria. These factors applied to the equation that determines the maximum specific growth rate establish a relation between the bacterial growth and the intrinsic and extrinsic factors that define the bacteria environment. These models may be programmed in low-cost wireless biochemical sensor devices applied to packaging and food supply chains to promote food safety and quality through real time traceability.

scholarly journals Preserving Porphyra umbilicalis and Saccharina latissima as Silages for Ruminant Feeding

Animals ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 1957
Author(s):  
Margarita Novoa-Garrido ◽  
Carlos Navarro Marcos ◽  
María Dolores Carro Travieso ◽  
Eduarda Molina Alcaide ◽  
Mogens Larsen ◽  
...  
Keyword(s):  
Dry Matter ◽  
Nutritional Value ◽  
Volatile Fatty Acids ◽  
Gas Production ◽  
Saccharina Latissima ◽  
Porphyra Umbilicalis ◽  
In Vitro Gas Production ◽  
Ruminal Degradability ◽  
Kinetics Of

The study analyzed the characteristics, chemical composition, and in vitro gas production kinetics of Porphyra umbilicalis and Saccharina latissima silages. Each seaweed was ensiled in vacuum bags (three bags/silage) following a 2 × 3 factorial design, with two pre-treatments (unwilted or pre-wilted) and three silage types: unwashed seaweed ensiled without additive; seaweed washed and ensiled without additive; and seaweed washed and ensiled with 4 g of formic acid (FAC) per kg seaweed. Silages were kept for 3 months in darkness at 20 °C. Pre-wilting prevented (p < 0.001) effluent formation and reduced (p ≤ 0.038) the production of NH3-N and volatile fatty acids for both seaweeds. Both pre-wilting and washing increased (p < 0.05) the ruminal degradability of P. umbilicalis silages but not of S. latissima silages. The pH of the FAC-treated silages was below 4.0, but ranged from 4.54 to 6.23 in non FAC-treated silages. DL-lactate concentrations were low (≤23.0 g/kg dry matter) and acetate was the predominant fermentation product, indicating a non-lactic fermentation. The estimated ruminal degradability of the P. umbilicalis and S. latissima silages was as average, 59.9 and 86.1% of that for high-quality rye-grass silages, respectively, indicating a medium-low nutritional value of these seaweed silages for ruminants.

Chemical characterization and in vitro fermentation ofBrassicastraw treated with the aerobic fungus,Trametes versicolor

2011 ◽  
Vol 91 (4) ◽  
pp. 695-702 ◽  
Author(s):  
J. E. Ramirez-Bribiesca ◽  
Y. Wang ◽  
L. Jin ◽  
T. Canam ◽  
J. R. Town ◽  
...  
Keyword(s):  
Mutant Strain ◽  
Trametes Versicolor ◽  
Lignin Degradation ◽  
Volatile Fatty Acids ◽  
Degradation Products ◽  
Chemical Characterization ◽  
Gas Production ◽  
In Vitro Fermentation ◽  
Lignin Degradation Products

Ramirez-Bribiesca, J. E., Wang, Y., Jin, L., Canam, T., Town, J. R., Tsang, A., Dumonceaux, T. J. and McAllister, T. A. 2011. Chemical characterization and in vitro fermentation of Brassica straw treated with the aerobic fungus, Trametes versicolor . Can. J. Anim. Sci. 91: 695–702. Brassica napus straw (BNS) was either not treated or was treated with two strains of Trametes versicolor; 52J (wild type) or m4D (a cellobiose dehydrogenase-deficient mutant) with four treatments: (i) untreated control (C-BNS), (ii) 52J (B-52J), (iii) m4D (B-m4D) or (iv) m4D+glucose (B-m4Dg). Glucose was provided to encourage growth of the mutant strain. All treatments with T. versicolor decreased (P<0.05) neutral-detergent fibre and increased (P<0.05) protein and the concentration of lignin degradation products in straw. Ergosterol was highest (P<0.05) in straw treated with B-52J, suggesting it generated the most fungal biomass. Insoluble lignin was reduced (P<0.05) in straw treated with B-52J and B-m4D, but not with B-m4Dg. Mannose and xylose concentration were generally higher (P<0.05) in straw treated with fungi, whereas glucose and galactose were lower as compared with C-BNS. The four treatments above were subsequently assessed in rumen in vitro fermentations, along with BNS treated with 2 mL g−1of 5 N NaOH. Concentrations of total volatile fatty acids after 24 and 48h were lower (P<0.05) in incubations that contained BNS treated with T. versicolor as compared with C-BNSor NaOH-treated BNS. Compared with C-BNS, in vitrodry matter disappearance and gas production were increased (P<0.05) by NaOH, but not by treatment with either strain of T. versicolor. Although treatment with T. versicolor did release more lignin degradation products, it did not appear to provide more degradable carbohydrate to in vitro rumen microbial populations, even when a mutant strain with compromised carbohydrate metabolism was utilized. Production of secondary compounds by the aerobic fungi may inhibit rumen microbial fermentation.

scholarly journals Chromate Reduction in Serratia marcescens Isolated from Tannery Effluent and Potential Application for Bioremediation of Chromate Pollution

2002 ◽  
Vol 2 ◽  
pp. 972-977 ◽  
Author(s):  
M.A. Mondaca ◽  
V. Campos ◽  
R. Moraga ◽  
C.A. Zaror
Keyword(s):  
Natural Waters ◽  
Waste Treatment ◽  
Environmental Concern ◽  
Electron Microscopic Examination ◽  
Tannery Effluent ◽  
Chromate Reduction ◽  
Bacterial Cells ◽  
Electron Microscopic ◽  
Treatment Processes ◽  
Transmission Electron

Pollution of aquatic systems by heavy metals has resulted in increasing environmental concern because they cannot be biodegraded. One metal that gives reason for concern due to its toxicity is chromium. Cr(VI) and Cr(III) are the principal forms of chromium found in natural waters. A chromate-resistant strain of the bacterium S. marcescens was isolated from tannery effluent. The strain was able to reduce Cr(VI) to Cr(III), and about 80% of chromate was removed from the medium. The reduction seems to occur on the cell surface. Transmission electron microscopic examination of cells revealed that particles were deposited on the outside of bacterial cells. A stable biofilm was formed in less than 10 h, reaching around 1010cfu attached per milligram of activated carbon. These findings demonstrate that immobilizedS. marcescensmight be used in industrial waste treatment processes.

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