scholarly journals Chemical Compositions and in vitro Methane Production Potentials of Some Agro-industrial By-products and Crop Residues

2019 ◽  
Vol 19 (8) ◽  
pp. 763-770
Author(s):  
Aberra Melesse ◽  
Herbert Steingass ◽  
Margit Schollenbe ◽  
Markus Rodehutsco
Nova Scientia ◽  
2020 ◽  
Vol 12 (24) ◽  
Author(s):  
Marcela Cárdenas-Manríquez ◽  
Rozlyn F. Young ◽  
Kathleen M. Semple ◽  
Carmen Li ◽  
Debora Coy ◽  
...  

Oil sands surface mining operations in northeastern, Alberta, Canada produce enormous volumes of fluid fine tailings, an aqueous suspension of fine clays, sand, unrecovered bitumen, and diluent hydrocarbons. The tailings are deposited and retained on-site in large settling basins where the colloidal solids sediment and consolidate very slowly by gravity and pore water collects at the surface for re-use. Tailings ‘biodensification’, mediated by indigenous microbes that produce methane and/or carbon dioxide, is a phenomenon observed in situ and in vitro whereby tailings with active anaerobic microbial communities consolidate and de-water faster than predicted by gravitational (self-weighted) consolidation alone. To exploit this phenomenon, we used organic amendments to stimulate endogenous anaerobic tailings microorganisms. Tailings from three different operators were amended with agri-business by-products, placed in 100-mL microcosms and 1.5-L settling columns, and monitored for methanogenesis, pore water recovery, and solids densification. Several amendments increased methane production and accelerated biodensification compared to unamended and negative controls. Hydrolyzed canola, blood meal, bone meal and glycerol generally accelerated biodensification, stimulated methane production and supported growth of methanogens and fermentative microbes. Amendment altered the chemistry of the tailings, generally decreasing pH, increasing conductivity and magnesium, potassium, sodium, and bicarbonate concentrations. Biodensification is a potential engineered technology for accelerating water recovery and reducing the volume of stored oil sands tailings.


Author(s):  
Khaoula Khelalfa ◽  
Rabah Arhab ◽  
Antonio Ignacio Martín-García ◽  
Nabila Zaabat ◽  
Alejandro Belanche

Condensed tannins are polyphenolic compounds which can exert beneficial effects in ruminants. They have the ability to bind proteins and decrease their degradation. They have also been reported to reduce methanogenesis and improve ruminants performances. The present work aimed to study the effect of purified condensed tannins from Acacia horrida extract on fermentation parameters, gas and methane production. In this context, seven substrates were selected: four Acacia species (Acacia pycnantha, Acacia dealbata, Acacia horrida and Acacia cyanophylla) and three plant by-products (date palm leaves, grenade peel and artichoke stems). Biological activity of tannins was evaluated by the incubation of the substrates in vitro with Polyethylene glycol (PEG). Tannins decreased concentration of all fermentation parameters (gas (p < 0.0001), methane (CH4) (p= 0.0983), ammonia (N-NH3) (p= 0.0382), Volatile Fatty Acids (VFA) (p= 0.0009), acetate (p <0.0001), propionate (p= 0.1024), butyrate (p= 0.0373), isobutyrate (p= 0.0046), valerate (p < 0.0001), isovalerate (p= 0.0032)). Substrates were also characterized by their content in main nutrients (dry matter (DM), organic matter (OM), ash, crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF) ,acid detergent lignin (ADL)) and in secondary metabolites (total phenols (TP), total tannins (TT) and condensed tannins (CT) ). All substrates presented high CP content except by-products (> 100 g/kg DM) and moderate cell-wall components. CT content was comprised between 120.5 and 680.4 g/kg DM in plants and between 23.1 and 170.4 g/kg DM in plant by-products. A. horrida presented the highest biological activity. Thus, their CT were extracted and purified on a sephadex LH-20 column. Purified tannins from A. horrida were incubated with two different forages alfalfa hay and barley straw at three different concentrations: 50, 100, 150 mg/g DM. Results showed that purified tannins from A. horrida had no effect on fermentation parameters (P > 0.05). The effects of A. horrida tannins may be strongly linked to their structure and their molecular weight more than to their concentration. For this reason, it is interesting that this work may be completed by physical characterization of these tannins.


2021 ◽  
Vol 348 ◽  
pp. 129063
Author(s):  
Susana Ferreyra ◽  
Carolina Torres-Palazzolo ◽  
Rubén Bottini ◽  
Alejandra Camargo ◽  
Ariel Fontana

Foods ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 703
Author(s):  
Severino Zara ◽  
Giacomo L. Petretto ◽  
Alberto Mannu ◽  
Giacomo Zara ◽  
Marilena Budroni ◽  
...  

The production of saffron spice generates large quantities of plant by-products: over 90% of the plant material collected is discarded, and a consideration fraction of this waste is plant stamens. This work investigated the chemical composition and the antimicrobial activities of the non-polar fraction extracted from four different saffron flower stamens. The chemical composition of ethereal extracts of the saffron stamens was qualitatively assessed by means of gas–chromatography-mass spectrometry (GC-MS) and nuclear magnetic resonance (NMR) analyses. These analyses revealed ethereal extracts to possess a high polyunsaturated fatty acid content. In vitro antibacterial activity of stamen extracts showed no large differences between Gram-positive and Gram-negative bacteria in terms of minimal inhibitory concentration (MIC). In food matrix microbial analysis of the bacterial strains belonging to the main foodborne pathogen species, including Staphylococcus aureus DSM 20231, Escherichia coli DSM 30083, and Listeria monocytogenes DSM 20600, using low-fat UHT milk, revealed a statistically significant reduction in the number of cells (particularly for E. coli and S. aureus with a complete elimination of the population of the two target bacteria following incubation in diethyl ether extracts of saffron stamen (DES) at high concentrations tested, both at 37 °C and 6 °C (for 48 h and 7 days, respectively). A synergic effect was observed when the pathogens were incubated at 6 °C with DES. This work shows these by-products to be excellent sources of bioactive compounds, which could be exploited in high-added-value products, such as food, cosmetics, and drugs.


2021 ◽  
Vol 3 (2) ◽  
Author(s):  
Avijit Dey ◽  
Shyam Sundar Paul ◽  
Puran Chand Lailer ◽  
Satbir Singh Dahiya

AbstractEnteric methane production contributes significantly to the greenhouse gas emission globally. Although, buffaloes are integral part of livestock production in Asian countries, contributing milk, meat and draft power, the contribution of enteric methane to environmental pollution attracts attention. The present study investigated the efficacy of garlic (Allium sativum) oil in reducing enteric methane production from buffaloes (Bubalus bubalis) by in vitro rumen fermentation. Garlic oil (GOL) was tested at four concentrations [0 (Control), 33.33 µl (GOL-1), 83.33 µl (GOL-2) and 166.66 µl (GOL-3) per litre of buffered rumen fluid] in 100-ml graduated glass syringes and incubated at 39℃ for 24 h for in vitro rumen fermentation study. Supplementation of GOL-1 increased (p < 0.05) total gas production in comparison with GOL-3; however, it remained comparable (p > 0.05) with control and GOL-2. Graded doses of garlic oil inclusions reduced (p < 0.001) methane concentration (%) in total gas and total methane production (ml/g DM), irrespective of concentrations. The feed degradability, volatile fatty acids and microbial biomass production (MBP) were not affected (p > 0.05) by GOL-1, but these tended to decrease in GOL-2 with marked reduction (p < 0.01) in GOL-3. The decrease (p < 0.01) in NH3–N concentration in fermentation fluid in the presence of garlic oil, irrespective of concentration, suggests reduced deamination by inhibiting rumen proteolytic bacterial population. The activities of ruminal fibrolytic enzymes (CMCase, xylanase, β-glucosidase, acetyl esterase) were not affected by lower dose (GOL-1) of garlic oil; however, reduction (p < 0.05) of these enzymes activity in rumen liquor was evident at higher doses (GOL-2 and GOL-3) of supplementation. This study shows positive impact of garlic oil supplementation at low dose (33.33 µl/l of rumen fluid) in reducing enteric methane production, thereby, abatement of environmental pollution without affecting feed digestibility.


Sign in / Sign up

Export Citation Format

Share Document