This research was carried out to evaluate the effects of flavone, myricetin, naringin, catechin, rutin, quercetin, and kaempferol at the concentration of 4.5% of the substrate (dry matter basis) on the rumen microbial activity in vitro. Mixture of guinea grass and concentrate (60 : 40) was used as the substrate. The results showed that all the flavonoids except naringin and quercetin significantly (P < 0.05) decreased the dry matter degradability. The gas production significantly (P < 0.05) decreased by flavone, myricetin, and kaempferol, whereas naringin, rutin, and quercetin significantly (P < 0.05) increased the gas production. The flavonoids suppressed methane production significantly (P < 0.05). The total VFA concentration significantly (P < 0.05) decreased in the presence of flavone, myricetin, and kaempferol. All flavonoids except naringin and quercetin significantly (P < 0.05) reduced the carboxymethyl cellulase, filter paperase, xylanase, and β-glucosidase activities, purine content, and the efficiency of microbial protein synthesis. Flavone, myricetin, catechin, rutin, and kaempferol significantly (P < 0.05) reduced the population of rumen microbes. Total populations of protozoa and methanogens were significantly (P < 0.05) suppressed by naringin and quercetin. The results of this research demonstrated that naringin and quercetin at the concentration of 4.5% of the substrate (dry matter basis) were potential metabolites to suppress methane production without any negative effects on rumen microbial fermentation.

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Rice cultivation generates large amount of crop residues of which only 20% are utilized for industrial and domestic purposes. In most developing countries especially southeast Asia, rice straw is used as part of feeding ingredients for the ruminants. However, due to its low protein content and high level of lignin and silica, there is limitation to its digestibility and nutritional value. To utilize this crop residue judiciously, there is a need for improvement of its nutritive value to promote its utilization through ensiling. Understanding the fundamental principle of ensiling is a prerequisite for successful silage product. Prominent factors influencing quality of silage product include water soluble carbohydrates, natural microbial population, and harvesting conditions of the forage. Additives are used to control the fermentation processes to enhance nutrient recovery and improve silage stability. This review emphasizes some practical aspects of silage processing and the use of additives for improvement of fermentation quality of rice straw.

Various pre-treatment techniques change the physical and chemical structure of the lignocellulosic biomass and improve hydrolysis rates. The effect of ultrasonic pre-treatment on oil palm empty fruit bunch (OPEFB) fibre prior to acid hydrolysis has been evaluated. The main objective of this study was to determine if ultrasonic pre-treatment could function as a pre-treatment method for the acid hydrolysis of OPEFB fibre at a low temperature and pressure. Hydrolysis at a low temperature was studied using 2% sulphuric acid; 1:25 solid liquid ratio and 100 degrees C operating temperature. A maximum xylose yield of 58% was achieved when the OPEFB fibre was ultrasonicated at 90% amplitude for 45min. In the absence of ultrasonic pre-treatment only 22% of xylose was obtained. However, no substantial increase of xylose formation was observed for acid hydrolysis at higher temperatures of 120 and 140 degrees C on ultrasonicated OPEFB fibre. The samples were then analysed using a scanning electron microscope (SEM) to describe the morphological changes of the OPEFB fibre. The SEM observations show interesting morphological changes within the OPEFB fibre for different acid hydrolysis conditions.

To produce titanium dioxide (TiO2) nanoparticle coatings, it is desirable that the nanoparticles are dispersed into a liquid solution and remain stable for a certain period of time. Controlling the dispersion and aggregation of the nanoparticles is crucial to exploit the advantages of the nanometer-sized TiO2particles. In this work, TiO2nanoparticles were dispersed and stabilized in aqueous suspensions using two common dispersants which were polyacrylic acid (PAA) and ammonium polymethacrylate (Darvan C). The effect of parameters such as ultrasonication amplitude and type and amount of dispersants on the dispersibility and stability of the TiO2aqueous suspensions were examined. Rupture followed by erosion was determined to be the main break up mechanisms when ultrasonication was employed. The addition of dispersant was found to produce more dispersed and more stabilized aqueous suspension. 3 wt.% of PAA with average molecular weight (Mw) of 2000 g/mol (PAA 2000) was determined to produce the best and most stable dispersion. The suspensions were then coated on quartz glass, whereby the photocatalytic activity of the coatings was studied via the degradation of formaldehyde gas under UV light. The coatings were demonstrated to be photocatalytically active.

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We evaluated the efficacy of supplementation of active Mitsuokella jalaludinii culture (AMJC) on the growth performance, nutrient use, and mineral concentrations in tibia bone and plasma of broiler chickens fed corn-soybean meal diets. Dietary treatments included low-nonphytate P (NPP) feed (containing 0.24% and 0.232% NPP for chicks from 1 to 21 and 22 to 42 d of age, respectively), low-NPP feed added with different levels of AMJC (equivalent to 250, 500, 750, and 1,000 U phytase/kg of feed), and normal-NPP feed (containing 0.46 and 0.354% NPP for chicks from 1 to 21 and 22 to 42 d of age, respectively). Supplementation of AMJC to low-NPP feed increased (P < 0.05) weight gain and feed intake and decreased (P < 0.05) feed:gain ratio of chickens during the whole experiment (Days 1 to 42). Supplementation of AMJC increased (P < 0.05) the AME value, digestibility of DM and CP, and retention of P, Ca, and Cu. Mn retention in broilers was only increased (P < 0.05) by AMJC supplementation from 18 to 20 d of age, and Zn retention was improved (P < 0.05) only at a high level of AMJC (equivalent to 1,000 U phytase/kg of feed) supplementation. Chicks fed low-NPP feed added with AMJC had similar tibia ash percentages as those fed the normal-NPP diet. Generally, supplementing AMJC to low-NPP feed increased (P < 0.05) Ca, decreased significantly (P < 0.05) Mn and Cu, but did not affect Zn and P concentrations in tibia ash. Supplementing AMJC also increased (P < 0.05) plasma P but had no effect on plasma Ca or Mn. Plasma Zn concentration was increased only when a high level of AMJC (equivalent to 1,000 U phytase/kg of feed) was used. In conclusion, AMJC supplementation to low-NPP feed improved growth performance; AME value; digestibility of CP and DM; use of Ca, P, and Cu; and bone mineralization.