Carboxymethylcellulase Activity Research Articles

Action of selenium against Sclerotinia sclerotiorum: Damaging membrane system and interfering with metabolism

Selenium (Se) in soil is beneficial for environmental stress tolerance of plants, and it has widespread toxic effects on pathogens. Based on the fact that Se significantly inhibited the growth of Sclerotinia sclerotiorum, we set experiments with different concentrations of Se to investigate the action of Se against S. sclerotiorum in this study. The results showed that Se (>0.5 mg L−1) changed the morphology of S. sclerotiorum mycelia, and higher Se concentrations severely damaged mycelial structures. Fourier transform infrared spectroscopy (FTIR) analysis indicated that Se treatment induced the chemical composition of mycelia with much abundance of functional groups such as alcohols, ketones, ammonium and esters, and 0.5 mg L−1 Se maximized their concentrations. Under Se treatments, the electrical conductivity of mycelia increased in a time-dependent manner, and osmolyte concentrations of mycelia increased as well. Se supplementation significantly reduced polymethylgalacturonase (PMG) and carboxymethylcellulase (Cx) activities, which protecting plants from infection, and increased the energy expenditure in S. sclerotiorum. Combined action of Se damage on membrane system, osmoregulation, reduction of cell wall degrading enzymes activities and improvement of energy expenditure resulted in the inhibition of S. sclerotiorum growth. Findings in this study provided evidences for using Se as a potential fungicide to control S. sclerotiorum.

Production of an environmentally friendly enzymatic feed additive for agriculture animals by spray drying abattoir’s rumen fluid in the presence of different hydrocolloids

Abstract The potential to use abattoir’s rumen fluid as a source to produce a carbohydrate degrading enzymatic feed additive by using spray-drying technique was studied. Rumen contents were taken from the slaughterhouse and powdered by spray drying with different hydrocolloids including sodium alginate (RA), guar gum (RG), chitosan (RC) and maltodextrin (RM) in two ratios (0.5 and 1% (w/v)). Fresh (RF) and spray dried rumen fluid without hydrocolloid materials (RN) were considered as controls. Residual activities compared to those measured in the fresh rumen fluid ranged from 68.6 (RC0.5) to 92.5% (RM1) for carboxymethyl cellulase, from 53.4 (RC1) to 73.2% (RM1) for avicelase, from 59.8 (RA0.5) to 84.6% (FM1) for amylase, and from 63.7 (RG0.5) to 95.8% (RM1) for filter paperase. Spray drying in the absence of a hydrocolloid resulted in 81.3% residual activity of carboxymethyl cellulase, 63.3% of avicelase, 68.6% of amylase, and 73.0% of filter paperase. The addition of 1% (w/v) maltodextrin was shown to retain the highest enzyme activities after spray drying. In addition, a dry matter degrading test was carried out to show the ability of the enzyme preparations at two concentrations (1 or 2% solution in phosphate buffer) to digest a typical dairy cow diet. At 1%, RF resulted in highest dry matter digestibility (P

English

Thermophiles are excellent sources of enzymes that can withstand and carry out reactions efficiently under high temperatures. This study isolated and characterised thermotolerant bacteria that produce enzymes of potential industrial value from five hot springs in Eritrea. A total of 65 bacterial isolates were obtained from the five hot springs. Out of the 65 isolates; 19 isolates produced a positive reaction for amylases, 36 for carboxymethyl cellulases, eight for proteases, 10 for xylanases and 11 for pectinases. More than half (36 out of 65) were able to produce carboxymethyl cellulases. Six isolates which showed carboxymethyl cellulase activity were from the genus Bacillus, while those belonging to Brevibacillus were seven. BLAST analysis of the partial sequences showed that 19 out of the 24 isolates sequenced showed high similarity (> 99%) to those of reference strains of the genera Bacillus and Brevibacillus available in the Genebank and EZ-taxon databases. The five isolates (E5, G2, G8, M1 and M13) that showed moderate similarities (97.2-99%) to strains from the Genebank and EZ-taxon databases were further characterized. Physiological characterization of the five selected isolates based on tolerance to NaCl, temperature and production of hydrolytic enzymes indicated that these isolates are potentially novel. Isolates G8 and M13 showed significantly higher amylase activity (p < 0.05) than the other three isolates. Caseinase activity recorded by the five isolates was the highest (p < 0.05) compared to other enzyme activities. The enzymes produced by thermotolerant bacteria from the five hot springs may be potentially useful for catalysis under harsh operational conditions encountered in industrial processes. Key words: Thermphilic, bacteria, thermozymes, hot springs, Eritrea.

Comparison of in vitro digestibility and chemical composition among four crop straws treated by Pleurotus ostreatus.

ObjectiveThe effects of Pleurotus ostreatus on the feed utilization of broad bean stalks (BBS), rape straw (RS), paddy straw (PS), and corn stalk (CS) was examined.MethodsThe four roughages were co-cultured with Pleurotus ostreatus. The chemical composition; enzyme activities of laccase, carboxymethylcellulase (CMCase) and xylanase; carbohydrate and protein fractions (based on The Cornell Net Carbohydrate and Protein System [CNCPS]) were assessed at different days after inoculation (7, 14, 21, 28 d) and un-inoculated roughages (control, 0 d). The digestibility of nutrient components and the gas production of roughage with various incubation times were monitored at 0, 2, 4, 6, 9, 12, 24, 36, 48, 60, and 72 h using an in vitro ruminal fermentation method.ResultsA higher CMCase activity (0.1039 U/mL) and earlier time to peak (14 d) were detected in Pleurotus ostreatus cultured with CS (p<0.05). Significantly, the incubation length-dependent responses of cumulative gas production were observed from 24 to 72 hours post fermentation (p<0.05), and these incubation length-dependent effects on cumulative gas production of PS and CS appeared earlier (24 h) for PS and CS than those (48 h) for BBS and RS (p<0.05). The fast-degradable carbohydrate (CA) content for all four roughages significantly increased over time (p<0.05). Nonetheless, increased degradation efficiency for CA treated with Pleurotus ostreatus was detected at both 21 and 28 days of incubation (p<0.05). With the exception of PS (p<0.05), there were no significant difference among the roughages (p>0.05) in slowly-degradable carbohydrate (CB2) at different incubation times (p<0.05).ConclusionAssessment of the alterations in chemical composition, CNCPS system fractions, and the fermentation kinetics after biological pretreatment may yield a valuable database for evaluating the biological pretreatment of Pleurotus ostreatus in ruminant feed.

The potential of rumen fluid waste from slaughterhouses as an environmentally friendly source of enzyme additives for ruminant feedstuffs

Abstract Rumen fluid disposal from slaughterhouses represents a major environmental challenge due to the presence of high levels of ammonia and phosphorus. The loading of these limiting nutrients into the soil and aquatic systems triggers eutrophication. Fortunately, the fluid is also rich in fibrolytic and other enzymes that could, alternatively, be used to enhance feed utilization in animals. Therefore, the aim of this study was to evaluate rumen fluid as a potential source of exogenous feed enzymes using a variety of test substrates. Hydrolytic enzyme activities of carboxymethyl cellulase, α-amylase and microcrystalline cellulase (avicellase) were measured in the rumen fluid to determine its enzymatic capabilities. Centrifuged and sonicated rumen fluid was used to pre-treat milled corn grain, barley grain, soybean meal, common vetch grain, bitter vetch grain, chickling vetch grain, alfalfa hay and common vetch straw substrates at 0, 1, 2, 3, or 4 mL per 100 g dry matter. Rumen fluid-treated substrates were subjected to a water solubility test and in vitro ruminal fermentation. The activities of carboxymethyl cellulase, avicellase and amylase were observed to be 377.8, 333.4 and 282 U/mL, respectively. Water solubility of dry matter in bitter vetch grain, chickling vetch grain, common vetch grain and soybean meal increased linearly with level of rumen fluid treatment. The highest solubility was observed in substrates treated with 4 mL rumen fluid per 100 g dry matter (P

Effects of concentrate-to-forage ratios and 2-methylbutyrate supplementation on ruminal fermentation, bacteria abundance and urinary excretion of purine derivatives in Chinese Simmental steers.

This study evaluated the effects of dietary concentrate levels and 2-methylbutyrate (2MB) supplementation on performance, ruminal fermentation, bacteria abundance, microbial enzyme activity and urinary excretion of purine derivatives (PD) in steers. Eight ruminally cannulated Simmental steers (12months of age; 389±3.7kg of body weight) were used in a replicated 4×4 Latin square design with a 2×2 factorial arrangement. Moderate-concentrate (400g/kg diet [MC]) or high-concentrate (600g/kg diet [HC]) diets were fed with or without 2MB (0g/day [2MB-] or 15.0g/day [2MB+]). Dry matter intake and average daily gain increased, but feed conversion ratio decreased with the HC diet or 2MB supplementation. Ruminal pH decreased, but total volatile fatty acid increased with the HC diet or 2MB supplementation. Molar proportion of acetate and acetate-to-propionate ratio decreased with the HC diet, but increased with 2MB supplementation. Propionate molar proportion and ruminal NH3 -N content increased with the HC diet, but decreased with 2MB supplementation. Neutral detergent fibre degradability decreased with the HC diet, but increased with 2MB supplementation. Crude protein degradability increased with the HC diet or 2MB supplementation. Abundance of Ruminococcus albus, Ruminococcus flavefaciens, Fibrobacter succinogenes and Bufyrivibrio fibrisolvens as well as activities of carboxymethyl cellulase, cellobiase, xylanase and pectinase decreased with the HC diet, but increased with 2MB supplementation. However, abundance of Prevotella ruminicola and Ruminobacter amylophilus as well as activities of α-amylase and protease increased with the HC diet or 2MB supplementation. Total PD excretion also increased with the HC diet or 2MB supplementation. The results suggested that growth performance, ruminal fermentation, CP degradability and total PD excretion increased with increasing dietary concentrate level from 40% to 60% or 2MB supplementation. The observed diet×2MB interaction indicated that supplementation of 2MB was more efficacious for improving growth performance, ruminal fermentation and total PD excretion with promoted ruminal bacteria abundance and enzyme activity in the MC diet than in the HC diet.

Bioethanol from sugarcane bagasse: Focused on optimum of lignin content and reduction of enzyme addition

To investigate the effect of delignification on enzymatic saccharification and ethanol fermentation of sugarcane bagasse (SCB), NaClO, NaOH, and Na2CO3 were used to prepare SCB with different lignin contents. We found that a lignin content of approximately 11% was sufficient for enzymatic saccharification and fermentation. Based on this result, an economical delignification pretreatment method using a combination of acid and alkali (CAA) was applied. Lignin content of 11.7% was obtained after CAA pretreatment with 0.5% w/v H2SO4 at 140 °C for 10 min and 1.0% w/v NaOH at 90 °C for 60 min. Presaccharification-simultaneous saccharification and fermentation (P-SSF) of the CAA-pretreated SCB resulted in an ethanol concentration of 43.8 g/L and an ethanol yield of 81.7%, with an enzyme loading of 15 FPU/g–CAA-pretreated SCB. Enzyme activities (filter paper, carboxymethyl cellulase, and β-glucosidase activities) were determined in liquid phase during P-SSF, indicating that the residual cellulase activity could be further used. Thus, fed-batch P-SSF was carried out, and an ethanol concentration of 43.1 g/L and an ethanol yield of 80.4% were obtained with an enzyme loading of 10 FPU/g–CAA-pretreated SCB. Fed-batch P-SSF was found to be effective to reduce enzyme loading.

Effects of tributyrin supplementation on short-chain fatty acid concentration, fibrolytic enzyme activity, nutrient digestibility and methanogenesis in adult Small Tail ewes

AbstractIn vivo and in vitro trials were conducted to assess the effects of tributyrin (TB) supplementation on short-chain fatty acid (SFCA) concentrations, fibrolytic enzyme activity, nutrient digestibility and methanogenesis in adult sheep. Nine 12-month-old ruminally cannulated Small Tail ewes (initial body weight 55 ± 5.0 kg) without pregnancy were used for the in vitro trial. In vitro substrate made to offer TB at 0, 2, 4, 6 and 8 g/kg on a dry matter (DM) basis was incubated by ruminal microbes for 72 h at 39°C. Forty-five adult Small Tail ewes used for the in vivo trial were randomly assigned to five treatments with nine animals each for an 18-d period according to body weight (55 ± 5.0 kg). Total mixed ration fed to ewes was also used to offer TB at 0, 2, 4, 6 and 8 g/kg on a DM basis. The in vitro trial showed that TB supplementation linearly increased apparent digestibility of DM, crude protein, neutral detergent fibre and acid detergent fibre, and enhanced gas production and methane emissions. The in vivo trial showed that TB supplementation decreased DM intake, but enhanced ruminal fermentation efficiency. Both in vitro and in vivo trials showed that TB supplementation enhanced total SFCA concentrations and carboxymethyl cellulase activity. The results indicate that TB supplementation might exert advantage effects on rumen microbial metabolism, despite having an enhancing effect on methanogenesis.

Interaction between the sequence of feeding of hay and concentrate, and boiling of barley on feed intake, the activity of hydrolytic enzymes and fermentation in the hindgut of Arabian mares.

The interaction between the sequence of feeding of hay and concentrate and the hydrothermal processing of barley in alleviating concentrate effects on intake, and hindgut fermentation in horses was tested. Six Arabian mares (4-10years of age, 410±35kg body weight) were used to evaluate the effects of feeding sequence (FS) and type of barley (TB) on intake, and faecal volatile fatty acids (VFA), activities of α-amylase (AA: EC 3.2.1.1), carboxymethyl cellulase (CMCase: EC 3.2.1.4), microcrystalline cellulase (MCCase: EC 3.2.1.91) and general filter paper degrading activity (FPD). Mares were offered a ration of air-dried alfalfa and concentrate (70:30 as-fed) in four subsequent periods of 14days including 8days of adaptation and 6days of sampling. In each period and each meal, mares received concentrate either 30min after (HC) or 30min before (CH) alfalfa hay. Barley was either milled or boiled in water. Rectal samples were grabbed directly from rectum once per period. Mares subjected to CH had higher dry matter intakes than mares under HC regime. The acetate:propionate ratio (A:P ratio) in rectal content was higher with CH than HC. The AA activity was higher under CH than under HC. Mares fed boiled barley had lower rectal concentrations of VFA and propionate and a higher A:P ratio than mares fed milled barley. Furthermore, the rectal content showed a higher MCCase activity but a lower AA activity when mares were fed boiled compared with milled barley. Interactions between FS and TB were observed with respect to CMCase activity, and concentrations of propionate and valerate. In conclusion, the present results suggest that both, feeding concentrate before hay and boiling the barley, might improve the hindgut environment in Arabian mares, and that the two measures were mostly additive and sometimes even synergistic.

Effects of traditional Chinese medicine formula on ruminal fermentation, enzyme activities and nutrient digestibility of beef cattle.

This study was conducted to evaluate effects of traditional Chinese medicine formula (TCMF) combined with several herbs on ruminal fermentation, enzyme activities and nutrient digestibility. Twenty finishing bulls were assigned to control or different TCMFs (Yufeisan-1, -2, -3; 2.5% dry matter (DM) in concentrate). Results showed that DM intake was higher (P<0.05) in the Yufeisan-3 group than others. Compared to control, apparent digestibility of crude protein and neutral detergent fiber were increased (P<0.05) by Yufeisan-3. No changes were observed in ruminal pH, concentrations of ammonia-N, microbial crude protein and total volatile fatty acid, whereas ratio of acetate to propionate was lower (P<0.05) and propionate proportion tended to be higher (P<0.1) in three TCMFs than control. Ruminal xylanase (P=0.061) and carboxymethylcellulase (P<0.05) activities were higher in Yufeisan-3 than control. No changes were observed in abundance of total bacteria, fungi and protozoa, whereas Fibrobacter succinogenes (P=0.062) and Ruminococcus flavefaciens (P<0.05) were increased and total methanogens was reduced (P=0.069) by Yufeisan-3 compared to control. Yufeisan-3 improved nutrient digestibility and ruminal enzyme activity, and modified fermentation and microbial community, maybe due to the presence of Herba agastaches, Cortex phellodendri and Gypsum fibrosum.

Enzyme profile of Shiitake mushroom strains grown on wheat straw

The mycelial growth abilities and extra cellular enzyme activities of nine different strains of shiitake cultivated on wheat straw were measured to establish predictable information on strain-substrate compatibility. The experimental results showed that the strains varied significantly in their mycelial growth rate, enzyme activities and in turn the biological efficiency. Fast mycelial colonization and higher amount of cellulase activity was observed in strain DMRO-327 with the highest mean fresh mushroom yield of 202.32 g per kg of wetted substrate. Correlation study was found significant between the initial speed of linear growth rate and biological efficiency of various strains. The rise in activity of carboxy methyl cellulase, FPase and xylanase during the primordial formation illustrated the role of these enzymes to promote fruiting of shiitake in straw based substrate. While decrease in the lignolytic enzymes with the time showed that these enzymes are responsible for substrate degradation. The conspicuous variations noticed in the morphometric observations also indicated the strain preference towards the given substrate.

Apparent digestibility, rumen fermentation, digestive enzymes and urinary purine derivatives in yaks and Qaidam cattle offered forage-concentrate diets differing in nitrogen concentration

Abstract Yaks (Bos grunniens) and Qaidam yellow cattle (Bos taurus) are indigenous to the Qinghai-Tibetan Plateau and graze natural pasture all year. Yaks are raised at higher elevations than cattle and are not offered supplementary feed whereas cattle receive supplementary feed and are sheltered at night during winters. We hypothesized that the species differ in metabolism of energy and nitrogen (N) and predicted that the differences would favour yaks to the harsh conditions of the plateau. To test our prediction, we examined nutrient digestibility, rumen fermentation, digestive enzymes and urinary purine derivatives (PD) in yaks and cattle offered forage-concentrate diets differing in N concentration. Four castrated yaks and 4 castrated cattle of similar ages (2.5 years) and body weights (200 kg) were used in two concurrent 4×4 Latin square designs. There was no difference (P > 0.05) between yaks and cattle in apparent digestibilities of dietary nutrients, concentrations of ruminal N components and activities of digestive enzymes (P > 0.05). Crude protein and acid detergent fiber digestibilities increased linearly (P 0.05), and both variables were not affected by dietary N content (P > 0.05). As dietary N increased, ruminal concentrations of ammonia, urea and amino acids increased linearly (all P 0.10) for both species. The activity of carboxymethylcellulase decreased linearly (P 0.10); however, the PD nitrogen index (PNI) was greater in yaks than in cattle for the lowest N diets (linear dietary N × species, P

Purification and characterization of a thermostable alkaline cellulase produced by Bacillus licheniformis 380 isolated from compost.

During composting processes, the degradation of organic waste is accomplished and driven by a succession of microbial populations exhibiting a broad range of functional competencies. A total of 183 bacteria, isolated from a composting process, were evaluated for cellulase activity at different temperatures (37, 50, 60, and 70°C) and pH values. Out of the 22 isolates that showed activity, isolate 380 showed the highest cellulase activity. Its ability to produce cellulase was evaluated in culture medium supplemented with carboxymethyl cellulose, microcrystalline cellulose, wheat straw, and rice husk. The culture medium supplemented with carboxymethyl cellulose induced higher enzyme activity after 6 hours of incubation (0.12 UEA mL-1 min-1). For wheat straw and rice husk, the results were 0.08 UEA mL-1 min-1 for both, while for microcrystalline cellulose, 0.04 UEA mL-1 min-1 were observed. The highest carboxymethyl cellulase activity was observed at 60°C (0.14 UEA mL-1 min-1) for both crude and partially purified enzyme after 30 and 120 min of incubation, respectively. Alkalinization of the medium was observed during cultivation in all substrates. The cellulase had a molecular mass of 20 kDa determined by SDS-Page. Isolate 380 was identified as Bacillus licheniformis. This work provides a basis for further studies on composting optimization.

Fermentable sugars production from lignocellulosic materials hydrolysis by thermophilic enzymes from Bacillus subtilis J12

Hot spring water and soil samples collected from various locations in Thailand were screened as thermophilic lignocellulase producers. Isolate J12, which showed the highest carboxymethylcellulase (CMCase) activity was selected for further enzymatic characterization. The isolate J12 exhibited both CMCase and xylanase acitvities. Optimum temperature for the J12 CMCase and xylanase acitvities were found to be the same at 60°C. But optimum pH were slightly different at pH 6.0 and 5.5, respectively. Both enzymes were stable at high temperatures and retained more than 60 % of their activities after 20 min at 60°C. Therefore, CMCase and xylanase produced from the selected bacterium showed thermophilic properties as to stability as well as activity. Plant degradation potential of J12 enzymes was also investigated using corncob and Napier grass. The result revealed that hydrolytic efficacy of this enzyme on corncob 13.2 % was superior to Napier grass at 9.6 %. Morphology and 16S rDNA sequencing results indicated that the bacterial isolate J12 was Bacillus sp.

The distribution of active β-glucosidase-producing microbial communities in composting.

The composting ecosystem is a suitable source for the discovery of novel microorganisms and secondary metabolites. Cellulose degradation is an important part of the global carbon cycle, and β-glucosidases complete the final step of cellulose hydrolysis by converting cellobiose to glucose. This work analyzes the succession of β-glucosidase-producing microbial communities that persist throughout cattle manure - rice straw composting, and evaluates their metabolic activities and community advantage during the various phases of composting. Fungal and bacterial β-glucosidase genes belonging to glycoside hydrolase families 1 and 3 (GH1 and GH3) amplified from DNA were classified and gene abundance levels were analyzed. The major reservoirs of β-glucosidase genes were the fungal phylum Ascomycota and the bacterial phyla Firmicutes, Actinobacteria, Proteobacteria, and Deinococcus-Thermus. This indicates that a diverse microbial community utilizes cellobiose. The succession of dominant bacteria was also detected during composting. Firmicutes was the dominant bacteria in the thermophilic phase of composting; there was a shift to Actinomycetes in the maturing stage. Proteobacteria accounted for the highest proportions during the heating and thermophilic phases of composting. By contrast, the fungal phylum Ascomycota was a minor microbial community constituent in thermophilic phase of composting. Combined with the analysis of the temperature, cellulose degradation rate and the carboxymethyl cellulase and β-glucosidase activities showed that the bacterial GH1 family β-glucosidase genes make greater contribution in cellulose degradation at the later thermophilic stage of composting. In summary, even GH1 bacteria families β-glucosidase genes showing low abundance in DNA may be functionally important in the later thermophilic phase of composting. The results indicate that a complex community of bacteria and fungi expresses β-glucosidases in compost. Several β-glucosidase-producing bacteria and fungi identified in this study may represent potential indicators of composting in cellulose degradation.

Notable fibrolytic enzyme production by Aspergillus spp. isolates from the gastrointestinal tract of beef cattle fed in lignified pastures.

Fungi have the ability to degrade vegetal cell wall carbohydrates, and their presence in the digestive tract of ruminants can minimize the effects of lignified forage on ruminal fermentation. Here, we evaluated enzyme production by Aspergillus spp. isolates from the digestive tracts of cattle grazed in tropical pastures during the dry season. Filamentous fungi were isolated from rumen and feces by culture in cellulose-based medium. Ninety fungal strains were isolated and identified by rDNA sequence analysis, microculture, or both. Aspergillus terreus was the most frequently isolated species, followed by Aspergillus fumigatus. The isolates were characterized with respect to their cellulolytic, xylanolytic, and lignolytic activity through qualitative evaluation in culture medium containing a specific corresponding carbon source. Carboxymethyl cellulase (CMCase) activity was quantified by the reducing sugar method. In the avicel and xilan degradation test, the enzyme activity (EA) at 48 h was significantly higher other periods (P < 0.05). Intra- and inter-specific differences in EA were verified, and high levels of phenoloxidases, which are crucial for lignin degradation, were observed in 28.9% of the isolates. Aspergillus terreus showed significantly higher EA for avicelase (3.96 ±1.77) and xylanase (3.13 ±.091) than the other Aspergillus species at 48 h of incubation. Isolates AT13 and AF69 showed the highest CMCase specific activity (54.84 and 33.03 U mg-1 protein, respectively). Selected Aspergillus spp. isolates produced remarkable levels of enzymes involved in vegetal cell wall degradation, suggesting their potential as antimicrobial additives or probiotics in ruminant diets.

Excellent waste biomass-degrading performance of Trichoderma asperellum T-1 during submerged fermentation

The random disposal and incineration of agricultural residues cause resources waste and environmental pollution. The potential of waste biomass for the production of alternative liquid fuels is increasing and the bioconversion of lignocellulose to fermentable monomeric sugars is essential for second-generation biofuel production. Here, natural and pretreated switch grass or rice straw were fermented by both Trichoderma asperellum T-1 and Trichoderma reesei QM6a, with the fermentation results highlighted the potential of T. asperellum T-1 in the degradation of natural waste lignocellulosic materials. In fermenting different substrates, the filter paper activity, β-glucosidase activity, xylanase activity and carboxymethyl cellulase activity of T-1 can respectively reach 1.88, 8.00, 7.15 and 20.52 times that of QM6a. Although acid pretreatment could improve the enzyme activities of both T-1 and QM6a, its effect on T-1 was much smaller than that on QM6a. Moreover, strain T-1 fermented the natural rice straw better than the pretreated rice straw. Therefore, T-1 is considered to be more suitable for the degradation of natural biomass, especially for the degradation of rice straw. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and scanning electron microscopy (SEM) showed that the cellulase series secreted by T. asperellum T-1 was more abundant, and its substrate deconstruction ability was stronger than T. reesei QM6a. All these results suggest the potential of T. asperellum T-1 in the degradation of natural waste lignocellulosic material, with practical benefits in terms of cost and pollution reduction.

Effects of dietary protein levels and rumen-protected pantothenate on ruminal fermentation, microbial enzyme activity and bacteria population in Blonde d'Aquitaine × Simmental beef steers

This study was undertaken to investigate the effects of dietary crude protein (CP) levels and rumen-protected pantothenate (RPP) supplementation on ruminal digestion kinetics, fermentation, microbial enzymatic activity, and selected bacterial species relative abundance in beef steers. Eight ruminally cannulated crossbred beef steers, with 15 months of age and 462±9kg of body weight (BW), were used in a duplicated 4×4 Latin square design by a 2×2 factorial arrangement. Low protein (113.7g/kg of CP [LP] or high protein (133.9g/kg of CP [HP]) diets were fed with or without RPP supplementation (0g [RP-] or 0.48g per kg dietary dry matter (DM) [RP+]). Steers were fed a total mixed ration containing dietary concentrate to corn silage ratio of 50:50 on a DM basis. There were no RPP×CP interactions for ruminal digestion kinetics, fermentation, microbial enzymatic activity, and selected bacterial species relative abundance, except for Ruminobacter amylophilus. Mean ruminal pH decreased with RPP supplementation, but was unaffected by dietary CP levels. Ruminal total VFA concentration increased with increasing dietary CP levels or RPP supplementation. Ruminal acetate percentage was similar among treatments, whereas propionate percentage decreased with increasing dietary CP levels or RPP supplementation. Consequently, the acetate to propionate ratio increased with increasing dietary CP levels or RPP supplementation. Ruminal ammonia-N content was unchanged among treatments. Both in situ ruminal DM degradability of corn silage and CP degradability of concentrate increased with RPP supplementation and tended to increase with increasing dietary CP levels, while NDF degradability of corn silage and DM degradability of concentrate increased with increasing dietary CP levels or RPP supplementation. Activities of carboxymethyl-cellulase, cellobiase, xylanase, pectinase, α-amylase and protease, populations of Ruminococcus albus, Ruminococcus flavefaciens, Butyrivibrio fibrisolvens and Prevotella ruminicola, and urinary excretion of purine derivatives increased with increasing dietary CP levels or RPP supplementation, but populations of Fibrobacter succinogenes and R. amylophilus increased with RPP supplementation, and decreased with increasing dietary CP levels. The results showed that increasing dietary CP levels from 113.7g to 133.9g or with 0.48g RPP supplementation improved ruminal fermentation and microbial protein synthesis by increasing microbial populations and enzymes activities.

Peach and Cherry Agroindustrial Wastes: New and Economic Sources for the Production of Lignocellulolytic Enzymes.

Pleurotus eryngii was incubated on both peach and cherry agroindustrial wastes by solid state fermentation for 30 days without/with pretreatment conditions. The lignocellulosic substrates were pretreated with dilute acid and alkaline solutions, hot water before incubation. The maximum carboxymethyl cellulase and xylanase activities peaked on 3rd and 5th days under control conditions of both wastes, respectively. The highest laccase and manganese peroxidase activities reached to their maximum on 17th day as 2193.06 ± 50.4 UL-1 and 732.73 ± 19.8 UL-1, respectively. The highest aryl alcohol oxidase activity was obtained as 239.25 ± 7.3 UL-1 in control condition of peach cultures. The used pretreatment methods had generally negative effects on lignocellulolytic enzyme production. The highest lignocellulolytic activities were detected using peach wastes. To results, these wastes could.

Effects of rumen-protected pantothenate on ruminal fermentation, microbial enzyme activity, cellulolytic bacteria and urinary excretion of purine derivatives in growing beef steers

This experiment was to evaluate the effects of rumen-protected pantothenate (RPP) on ruminal fermentation, microbial enzyme activity, bacteria population and urinary excretion of purine derivatives in growing beef steers. Eight ruminally cannulated first-generation crossbred (Blonde d′Aquitaine × Simmental) beef steers, averaging 12 months of age and 363 ± 7kg of body weight (BW), were allocated into a replicated 4 × 4 Latin square design. Four treatments were control, low-RPP (LRPP), medium-RPP (MRPP) and high-RPP (HRPP) with 0, 0.32, 0.48 and 0.64g RPP per kg dietary DM, respectively. Steers were fed a total mixed ration and dietary concentrate to corn silage ratio was 50:50 based on a dry matter (DM) basis. The experiment included four periods and lasted for 96 days, each period contained 14 days of adaptation and 10 days of data collection. Ruminal pH decreased linearly with increasing RPP supplementation and was lower for MRPP than for control. Ruminal total VFA concentration increased linearly with increasing RPP supplementation and was higher for MRPP than for control. The acetate to propionate ratio increased linearly due to the unchanged acetate molar proportion and the tendency towards decreased propionate proportion. Ruminal DM and neutral detergent fibre degradability of corn silage increased quadratically, whereas DM and crude protein degradability of concentrate mix increased linearly with increasing RPP supplementation. Activities of carboxymethyl-cellulase, cellobiase, xylanase and α-amylase increased linearly and was higher for MRPP than for control. Populations of R. albus, R. flavefaciens, F. succinogenes, B. fibrisolvens, P. ruminicola and R. amylophilus increased linearly and quadratically with increasing RPP supplementation. Urinary excretion of purine derivatives increased linearly with increasing RPP supplementation and was higher for HRPP and MRPP than for LRPP and control. The results indicated that dietary supplementary RPP improved ruminal fermentation, in situ ruminal degradation and urinary excretion of purine derivatives by stimulating bacteria growth and microbial enzymes secretion. It is suggested that supplementary RPP regulated bacteria growth and microbial enzymes secretion in a dose-dependent manner. Under the current experimental condition, the appropriate dose of RPP was at 0.48g per dietary DM for growing crossbred beef steer.