Non-starch polysaccharides from sunflower (Helianthus annuus) meal and palm kernel (Elaeis guineenis) meal—preparation of cell wall material and extraction of polysaccharide fractions

Two different chemical methods, sequential extraction with alkali and sodium chlorite and treatment with 4-methylmorpholine N-oxide (MMNO), were applied to the extraction of non-starch polysaccharides (NSP) from the enzymically deproteinated, water-insoluble cell wall materials of sunflower (Helianthus annuus L) meal and palm kernel (Elaeis guineensis Jacq) meal. The NSP content accounted for 550 g kg^?1 (sunflower meal) and 750 g kg^?1 (palm kernel meal) of the cell wall materials. Neither of the treatments alone was capable of solubilising more than about half of the original NSP. Combined treatment using alkali/chlorite followed by MMNO completely dissolved cell wall material from palm kernel meal, whereas a small residue (40 g kg^?1 of original NSP) was left in sunflower meal. Loss of NSP occurred with both methods (total NSP recovery ranging from 88% for alkali/chlorite extraction of sunflower to 64% for MMNO extraction of palm kernel). Due to differences in solubility revealed upon acidification and/or dialysis, extracts became subdivided into precipitates and soulble fractions. The sugar composition of the resulting fractions enabled a tentative identification of teh major non-starch polysaccharides; sunflower meal was found to contain cellulose, (acidic) xylans, polyuronide-containing fractions and xyloglucan; palm kernel meal was found to contain mannans, cellulose and xylans, with the major part of the mannans originating from the endosperm and the xylans being almost exclusively located in the endocarp.     

Protein quality of some Nigerian feedstuffs. II. Biological evaluation of protein quality

The protein quality of some Nigerian protein concentrates were studied by conventional protein quality techniques using weanling albino rats of the Wistar Strain. The true digestibility of the concentrates were between 90 and 98% for most of the feedstuffs examined, except the cashew nut scrap kernel meals I and II, (84.6 and 84.3%); the African locust bean seed only (75.9%); the African locust bean seed and pulp (81.6%); and the palm kernel meal (74.2%) which showed significantly lower values than the others. The animal protein sources examined (milk powder, casein, fishmeals and egg) were found to show superior p.e.r., n.p.r., p.r.e., n.p.u. and b.v. values to those observed for the cashew nut samples, African locust bean seed, groundnut and palm kernel meal. Blood meal, however, could not support the growth of rats and showed poor protein quality indices: ?2.46, 0.83, 16.1, 18.9 and 19.3 for the p.e.r., n.p.r., p.r.e., n.p.u. and b.v., respectively. The cashew nut scrap kernel meal samples I and II with protein values in the range 0.76 to 1.12, 2.86 to 3.13, 45.7 to 50.1, 41.3 to 46.7 and 48.9 to 55.3 for p.e.r. n.p.r., p.r.e., n.p.u. and b.v., respectively, were poorer compared to the good grade kernel meal with values of 2.01, 4.01, 64.2, 63.0 and 68.6 for p.e.r., n.p.r., p.r.e., n.p.u. and b.v., respectively, probably as a result of more severe heat damage. The African locust bean seed samples could not support the growth of rats, gave negative p.e.r. (?3.19 to ?2.54); low n.p.u. and b.v. (19.8 to 20.9 and 22.3 to 23.7). The palm kernel meal, despite its apparent balance of amino acids showed poor protein quality indices: 1.27, 2.62, 42.0, 44.1 and 56.7 for p.e.r., n.p.r., p.r.e., n.p.u. and b.v., respectively, attributable to its high fibre content and a concomitant lowering of the digestibility.     

Predicting in-vivo digestibilities of herbages by exhaustive enzymic hydrolysis of cell walls

A potent cellulase solution was prepared from culture filtrates of an artificially-produced mutant of Trichoderma species. The filtrates were diluted to provide a standardised, simulated rumen liquor which was then used to study the correlation between cellulase digestibility and in-vivo digestibility of a range of plant materials. Cell walls of whole, dried plant material were either not attacked by the cellulase or were attacked only very slowly, but cell walls isolated by neutral-detergent extraction were readily hydrolysed. Cellulase digestibility, defined as the percentage of whole, dry plant material solubilised by neutral-detergent extraction followed by exhaustive hydrolysis with standardised cellulase, was highly correlated with in-vivo dry matter digestibility (DMD) (r=0.98) and predicted that parameter with reasonable accuracy (r.s.d., residual standard deviation = 2.83). The form of the regression equation was in-vivo DMD = 0.98 × cellulase solubility - 10.12, suggesting that the same factors limited cellulase and in-vivo digestibility. The method was simple and reliable and results were known within 48 h.     

The influence of the variety of barley and level of nitrogen fertilisation on the digestibility and metabolisable energy value of barley meal in the pig

Metabolism studies were carried out with 45 kg pigs to examine barley meal from the varieties Golden Promise, Maris Mink, Lami, Zephyr and Abacus, all with similar nitrogen (N) content, and barley meal from the variety Zephyr which had received four different levels of N fertilisation. There were no significant differences (P > 0.05) between varieties for the apparent digestibility coefficients of gross energy (GE) and proximate constituents, the least significant difference for GE and N being 0.025 and 0.089 of the respective means. The mean digestible energy (DE) and metabolisable energy (ME) values were 14.48 and 14.07 MJ/kg dry matter (DM). The mean apparent digestibility of N was 0.685. The apparent digestibility coefficients of GE and N of meal from the variety Zephyr increased with N content. The increase in DE value with N content could be attributed to the increase in N digestibility.     

The use of feather and offal meal to replace mainly soyabean meal in a fishmeal-free basal diet for caged layers and the effect of the addition of methionine to the basal diet

An experiment is described in which feather and offal meal was used at levels of 0, 2.6, 5.2 and 7.8 and 10.4% to replace soyabean meal and at a level of 14.0% to replace both soyabean meal and meal and bone meal in a non-fish meal containing control diet fed to light hybrid caged layers. Replacement of the soyabean meal by feather and offal meal did not adversely affect total or mean egg weight up to the 7.8% level of addition. The efficiency of utilisation of metabolisable energy (ME) for egg production was adversely affected at the higher levels of addition. The addition of 0.07% DL-methionine to the control diet resulted in a statistically significant improvement in percentage production, total egg weight and efficiency of ME utilisation. Mould growth occurred in stored feather and offal meal when the dry matter content was below about 90%. The proximate, Ca, P and amino-acid analyses of the feather and offal meal are presented.     

Nutritional effects of including different levels and sources of protein in milk replacers for calves

Two digestibility and nitrogen balance experiments were carried out with groups of young calves given high-fat milk replacers reconstituted with water and fed in liquid form. In the first experiment six different milk replacers with crude protein contents ranging from 12.7 up to 27.6% in the dry matter were compared, the differences in protein content being brought about by adjustments to the level of separated milk protein used in the replacers. The apparent digestibility of organic matter was very high on all the treatments and unaffected by level of protein. Although the crude protein fraction showed an increase in apparent digestibility with increase in level of protein, its true digestibility was estimated to be virtually 100% on all the treatments. Retention of nitrogen expressed as a percentage of total intake remained fairly constant for diets containing from 18.8 to 27.6% of crude protein and the weight of nitrogen retained increased with each successive increase in level of dietary protein. In the second experiment the effects of replacing half of the milk protein in a control milk replacer by different forms of animal protein were studied. The true digestibilities of the total dietary protein on the treatment containing only separated milk protein and on the other treatments containing partial substitution by dried delactosed whey, dried blood, white fish meal and meat meal were found to be 94.1, 90.9, 85.4, 91.1 and 86.6%, respectively. Their biological values were 74.7, 70.3, 69.1, 66.0 and 65.5%, respectively. A sixth treatment in which the meat meal was provided with an enzyme supplement did not effect any significant change in either digestibility or biological value. Retentions of nitrogen expressed as percentages of intake were significantly lower on all the treatments containing partial replacement of separated milk protein by the other sources of protein than on the control treatment.     

The effect of pepsin pretreatment of herbage on the prediction of dry matter digestibility from solubility in fungal cellulase solutions

Cellulase preparations from different fungi differed markedly in their ability to solubilise herbage and cellulose; T. viride cellulase was the most active, solubilising 70% of cellulose paper in 24 h. The correlation of cellulase solubility with the in vivo and in vitro dry matter digestibility of grasses, and with the in vitro digestibility of legumes was markedly improved by pretreatment of the herbage with acid pepsin. Using the two stage technique, closely similar regression lines were obtained for predicting the in vitro digestibility of both grasses and legumes. Use of the pepsin treatment also enabled a less active Basidiomycete cellulase to be used with results very similar to those obtained with the T. viride enzyme. The technique is proposed as a more rapid, convenient and precise method of predicting digestibility than the usual in vitro procedure.     

Enzyme—Pretreatment of Pinto Bean High Protein Fraction and Time of Blending Corn Meal Affects Extrudate Properties

High protein fraction of pinto bean, treated with papain and cellulose enzymes (Solvay Enzymes Inc.), was blended with corn meal (30%) and extruded at 120°C. Changes in expansion, texture, color, pH, in vitro protein digestibility, reducing sugars and functional properties of extmdates were recorded. Changes depended on type of enzymes and time of corn incorporation (before or after enzymatic pretreatment). The best texture of the extrudates was obtained using a cellulase enzyme. Papain affected some functional properties such as NSI and WSI. The best improvement in in vitro protein digestibility and reducing sugars was found with a cellulase treatment. Protein and fiber could be modified to improve physicochemical and functional properties of extrudates.     

Nutritive value of cassava root meal enriched by trichoderma harzianum for chickens

A study was conducted with chickens to establish the content of metabolisable energy (ME) and the content and apparent digestibility of crude protein (CP) and amino acids (AA) in cassava root meal (CRM) enriched by the fungus Trichoderma harzianum. The ME content of this enriched CRM was found to be about 9.1 MJ kg^?1 dry matter (DM). This value was significantly lower (P<0.05) than that of non-enriched CRM (12.2 MJ kg^?1 DM). The CP content of the enriched CRM product used was 37.6 on DM basis. The non-protein nitrogen content accounted for about 30% of the total CP value. The mean apparent digestibility coefficient of the CP was about 66% whereas that of AA was about 81%. Data from this study indicate that fungal enriched CRM could be used in chicken diets.     

Effect of the insoluble dietary fibre from oil palm fat-free flour on digestibility in rats

This work shows the results of comparing the effects of the insoluble dietary fibre from oil palm fat-free flour and cellulose on the growth, weight, humidity and composition of faeces in adult rats (Sprague–Dawley). Five groups of rats were fed for 4 weeks. The control group was fed with a diet free of fibre, and the remaining four groups with diets containing 50 or 100 g of either oil palm fat-free flour or cellulose, respectively. The adaptation period was 4 days. The evolution of growth and food intake did not vary significantly p<0.05 regardless of the type of diet. On the other hand, faeces excretion increased by 3.3–4.7 g/day in the groups of rats fed with oil palm fat-free flour, while it increased by only 3.1–4 g/day in diets based on cellulose. A higher content of water was observed in the faeces of rats fed with insoluble dietetic fibre from oil palm fat-free flour. The apparent digestibility of the insoluble dietary fibre of oil palm fat-free flour was low (35%), showing resistance to fermentation. The digestibility of the protein tended to decrease more with the insoluble dietary fibre of oil palm than with the cellulose, which may be related. ©     

In vitro digestibility of individual amino acids in rumen-undegraded protein: The modified three-step procedure and the immobilized digestive enzyme assay

Three soybean meal, 3 SoyPlus (West Central Cooperative, Ralston, IA), 5 distillers dried grains with solubles, and 5 fish meal samples were used to evaluate the modified 3-step in vitro procedure (TSP) and the in vitro immobilized digestive enzyme assay (IDEA; Novus International Inc., St. Louis, MO) for estimating digestibility of AA in rumen-undegraded protein (RUP-AA). In a previous experiment, each sample was ruminally incubated in situ for 16 h, and in vivo digestibility of AA in the intact samples and in the rumen-undegraded residues (RUR) was obtained for all samples using the precision-fed cecectomized rooster assay. For the modified TSP, 5 g of RUR was weighed into polyester bags, which were then heat-sealed and placed into Daisy^II incubator bottles. Samples were incubated in a pepsin/HCl solution followed by incubation in a pancreatin solution. After this incubation, residues remaining in the bags were analyzed for AA, and digestibility of RUP-AA was calculated based on disappearance from the bags. In vitro RUP-AA digestibility estimates obtained with this procedure were highly correlated to in vivo estimates. Corresponding intact feeds were also analyzed via the pepsin/pancreatin steps of the modified TSP. In vitro estimates of AA digestibility of the feeds were highly correlated to in vivo RUP-AA digestibility, which suggests that the feeds may not need to be ruminally incubated before determining RUP-AA digestibility in vitro. The RUR were also analyzed via the IDEA kits. The IDEA values of the RUR were good predictors of RUP-AA digestibility in soybean meal, SoyPlus, and distillers dried grains with solubles, but the IDEA values were not as good predictors of RUP-AA digestibility in fish meal. However, the IDEA values of intact feed samples were also determined and were highly correlated to in vivo RUP-AA digestibility for all feed types, suggesting that the IDEA value of intact feeds may be a better predictor of RUP-AA digestibility than the IDEA value of the RUR. In conclusion, the modified TSP and IDEA kits are good approaches for estimating RUP-AA digestibility in soybean meal products, distillers dried grains with solubles, and fish meal samples.     

Influence of synchronizing protein and starch degradation in the rumen on nutrient utilization and microbial protein synthesis

A 4 x 4 Latin square design with four multiparous cows in midlactation fitted with duodenal cannulae was used to determine the effect of synchronization of protein and starch degradation in the rumen on nutrient availability in lactating cows. As major starch and protein sources, diets contained: barley plus cottonseed meal; barley plus brewers dried grains; milo plus cottonseed meal; and milo plus brewers dried grains. Experimental periods were 12 d and consisted of 8 d adjustment and 4 d collection. Chromium oxide was used as the marker to determine digestibility and nutrient flow from the rumen. Microbial protein synthesis was estimated from nucleic acid content in duodenal samples. Apparent and corrected rumen digestibilities of DM, organic matter, CP, and starch were higher for diets containing barley than milo but were not affected by protein source. For diets containing barley and milo, starch digested postruminally averaged 820 and 2190 g/d and percentage digestibility was 70 and 77%. No difference among diets was found in DM, organic matter, and CP flow to the small intestine; however, microbial N synthesis was higher in diets containing barley than in diets containing milo.     

The effect of by-product inclusion level on milk production,nutrient digestibility and excretion,and rumen fermentation parameters in lactating dairy cows offered a pasture-based diet

The objective of this study was to investigate the effects of replacing barley and soybean meal with increasing levels of by-products on production, digestive, and metabolic parameters in early-mid lactation dairy cows offered perennial ryegrass-based pasture. Forty-eight (32 multiparous and 16 primiparous) dairy cows that were 64 ± 24 d in milk were assigned to 1 of 4 pasture-based dietary treatments (n = 12) in a randomized block design experiment that ran for 70 d. Treatments consisted of a perennial ryegrass-based pasture and 1 of 4 supplementary concentrates: BP35, BP55, BP75, and BP95 containing 35, 55, 75, and 95% by-products, respectively, in the concentrate on a dry matter basis. The by-products used were soyhulls, dried distillers grains, and palm kernel extract in equal proportions. Barley and soybean meal were replaced as by-product inclusion level increased. In this study, intakes of pasture dry matter (15.7 kg) and total dry matter (21.1 kg) were not affected by treatment. Similarly, milk production parameters (milk yield, milk composition, somatic cell count, and urea) were not different between treatments. Unsaturated fatty acids were lower in the milk of cows offered BP35 and BP55 compared with those offered BP75 and BP95. Concentrations of β-hydroxybutyrate, nonesterified fatty acids, and other blood metabolites were within normal range and did not differ between treatments, and cow body condition score and body weight were also not different. Equally, N was unaffected by diet. Blood urea N was lower in the BP75 group compared with BP35. This study demonstrated that barley and soybean meal can be replaced with soyhulls, dried distillers grains, and palm kernel extract without affecting milk production, digestive, or metabolic parameters in dairy cows offered a pasture-based diet.     

Fuels derived from starch digestion have different effects on energy intake and metabolic responses of cows in the postpartum period

Absorbed fuels from the digestion of starch include propionic acid (PA) produced by ruminal fermentation and glucose (GLU) from intestinal digestion, which may be partially metabolized to lactic acid (LA) by intestinal tissues. Our objective was to evaluate the effects of these fuels on dry matter intake (DMI) and feeding behavior of cows in the postpartum period. We hypothesized that these fuels affect feed intake differently and that their effects are related to differences in their hepatic metabolism. Glucose was expected to have little effect on feed intake because little or no GLU is extracted from the blood by the liver. Whereas both LA and PA are anaplerotic and can stimulate oxidation of acetyl CoA in hepatocytes, hepatic extraction of PA is greater than LA, which depends on cytosolic redox state. Continuous isoenergetic infusions (150 kcal of ME/h) of PA, LA, or GLU or no infusion were administered abomasally to 8 ruminally cannulated multiparous Holstein cows (12.4 ± 6.2 d postpartum) in a duplicate 4 × 4 Latin square design experiment, with four 1-d infusion periods, balanced for carry-over effects. Treatment sequences were assigned to cows randomly, and treatments included control (CON, no infusion), PA (0.41 mol/h), LA (0.46 mol/h), and GLU (0.22 mol/h). Solutions containing treatments were infused at 500 mL/h for 22 h/d and provided ～3.3 Mcal/d. Feeding behavior was recorded by a computerized data acquisition system. Gross energy digestibility of the diet was determined for each cow and used to calculate metabolizable energy intake (MEI) from the diet. Total MEI was calculated as the sum of MEI from the diet plus energy from infusions. Data were analyzed statistically with a mixed model including the fixed effect of treatment and random effects of block and cow within block. Each treatment was compared with CON by contrasts. Compared with CON, PA decreased DMI by 24% (14.3 vs. 18.9 kg/d) and total MEI by 13% (34.8 vs. 40.2 Mcal/d) with a tendency to decrease meal frequency. Lactic acid decreased DMI by 14% (16.3 vs. 18.9 kg/d) compared with CON by decreasing meal size 20% but did not affect MEI. Glucose infusion did not affect DMI or MEI. Treatment effects on DMI and MEI were consistent with their expected effects on hepatic oxidation. Depression of feed intake in diets containing highly fermentable starch is likely because of differences in hepatic metabolism.     

A cellulase digestion technique for predicting the dry matter digestibility of grasses

A digestion technique using a commercially-available crude cellulase preparation from Trichoderma viride is described. The enzyme showed cellulase, hemicellulase and proteolytic activity when tested on herbage or herbage polysaccharides. A high correlation (r = 0.92, P < 0.001, residual standard deviation 2.5) was found between a simple one stage enzyme digestion and in vivo dry matter digestibility for a range of grass species and varieties. In vitro dry matter digestibility and detergent fibre were also determined on the same samples and the results correlated with in vivo dry matter digestibility. The cellulase method is rapid and reproducible and particularly well suited for the evaluation of plant material in breeding programmes.     

豆粕异黄酮酶法提取的研究

大豆异黄酮是一类具有重要生理作用的植物雌激素，从豆粕中提取异黄酮具有重要的经济意义。在常规的醇提工艺前用纤维素酶或木聚糖酶预处理，能明显提高大豆异黄酮的提取得率。纤维素酶的最适用量为15FPIU／g豆粕，处理24h后，总异黄酮含量和未经酶处理的相比，可增加1．9倍。采用木聚糖酶对豆粕进行预处理，当酶用量为200IU／g豆粕时，作用36h后，总异黄酮含量可增加2．2倍。纤维素酶和木聚糖酶协同作用有利于提高豆粕异黄酮的得率，在每g豆粕的酶用量为5FPIU纤维素酶和100IU的木聚糖酶的条件下，作用36h后，异黄酮得率为59mg／10g豆粕，是酶未处理的2．2倍。     

响应面试验优化红松松仁膳食纤维制备工艺及其理化性质分析

以红松松仁粕为原料制备松仁膳食纤维,利用响应面法优化制备工艺条件,并对其相关性质进行分析。通过比较筛选碱性蛋白酶为最适酶,选择pH值、加酶量、酶解温度、酶解时间4 个影响因素,在单因素试验基础上通过响应面试验设计,得到最优酶解工艺条件,并对此条件下得到的膳食纤维性质进行分析。结果表明：制备膳食纤维最优工艺条件为pH 9.2、碱性蛋白酶加酶量10 148 U/g、酶解温度50 ℃、酶解时间3.1 h,膳食纤维含量可达77.67%。相对于松仁粕,其持水力、膨胀力、持油力分别提高了24.17%、25.95%、40.44%,溶解性降低了63.94%。松仁粕经酶解后得到的膳食纤维具有较好的性能,对于实际应用具有重要意义。     

Enzymatic treatment of sunflower kernels before oil extraction

Sunflower kernels were enzymatically treated before pressing, with the aim of enhancing oil extractability. Following the response surface methodology, the combined effects of moisture, enzyme/kernel ratio and treatment time were examined. The effect of these variables on the pressing efficiency, the protein digestibility, the fiber content and the meal color was assessed. In a wide range of conditions, it was found that the pressing efficiency was higher for treated kernels, obtaining 13% additional oil compared with untreated samples. Also, the in vitro apparent digestibility coefficient of the meal was improved and the total fiber content was reduced. A slight darkening of the meal was observed as a result of the operational conditions during the treatment. The solvent extractability of the enzymatically treated pressed cakes was enhanced compared with that of the untreated sample.     

Cellulase methods for the efficient digestion of grasses and brassicas

A cellulase solubility method for the prediction of grass digestibility was modified by changing pepsin pretreatment conditions so that cellulase values were as high as those obtained using rumen liquor. Raising temperature from 40 to 50°C and acid concentration from 0.1 to 0.125_N during 'pepsin' treatments given before the cellulase stage, increased digestion by 3 to 10% depending on the type of grass, up to the level reached by rumen liquor. For samples of brassicas (digestibilities ranging from 66 to 84%) milder pretreatment conditions were sufficient to give cellulase digestion values as high as rumen liquor estimates.     

Aqueous enzymatic process assisted by microwave extraction of oil from yellow horn (Xanthoceras sorbifolia Bunge.) seed kernels and its quality evaluation

In this study, aqueous enzymatic process (AEP) assisted by microwave extraction (ME) of oil from yellow horn (Xanthoceras sorbifolia Bunge.) seed kernel was investigated. Central composite design (CCD) and response surface methodology (RSM) were used to optimise an enzyme cocktail (cellulase, hemicellulase, pectinase) for AEP. The main factors of ME were also studied. A maximal oil extraction yield of 55.8% was achieved under optimal conditions. Moreover, scanning electron microscope (SEM) was applied to characterise the extraction process. Analysing chemical composition of the extracted oil by GC–MS showed that the content of unsaturated fatty acids by this emerging method (91.18%) was similar to that by conventional organic solvent extraction (88.76%). In addition, the main physicochemical properties and antioxidant activities of yellow horn oil were measured to evaluate its quality. The present research supported necessary data for the green extraction method of edible oil in food industry.