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1.
For the identification and characterisation of major non-starch polysaccharides from sunflower (Helianthus annuus L) meal and palm-kernel (Elaeis guineensis Jacq) meal, extracts obtained by sequential alkaline extraction and delignification of the corresponding cell wall materials were subfractionated by graded ethanol precipitation and size-exclusion and adsorption chromatography. Determination of the sugar and glycosidic linkage composition of extracts and subfractions and intact cell wall materials allowed the identification and quantification of a variety of polysaccharides. In sunflower meal, cellulose (42% of total non-starch polysaccharides), pectic polysaccharides (24%), (4-O-methyl)-glucuronoxylans with 8-11% uronic acid substitution (24%), (gluco)mannans (5%) and fucoxyloglucans (4.5%) were encountered. Major polysaccharides in palm-kernel meal were linear mannans with very low galactose substitution (78% of total non-starch polysaccharides), followed by cellulose (12%) and small amounts of (4-O-methyl)-glucuronoxylans and arabinoxylans (3% each).  相似文献   

2.
Fibre composition of the following 13 apple cultivars was studied: ‘Cortland’, ‘Empire’, ‘Fuji’, ‘Golden Delicious’, ‘Gala’, ‘Granny Smith’, ‘Jonagold’, ‘Mutsu’, ‘McIntosh’, ‘Delicious’, ‘Rome’, ‘Stayman’ and ‘York’. Fruit samples from each of these cultivars were analysed for non-starch cell wall materials (NSCWM) and non-starch polysaccharides (NSP). NSCWM was further fractionated into soluble and insoluble fibre fractions. Both NSCWM and NSP content were found to be significantly influenced by cultivar. NSCWM content ranged from 19·1 g kg−1 apple flesh in ‘Fuji’ to 36·2 g kg−1 in ‘York’. Mean(±SD) NSCWM content of all the cultivars was 23·1±4·5 g kg−1. NSP content of apple flesh ranged from 13·8 g kg−1 in ‘McIntosh’ to 28·7 g kg−1 in ‘York’ with the overall mean for all cultivars being 17·9±4·2 g kg−1. Relative amount of monosaccharides found in the hydrolysates of apple fibre also varied among cultivars. The greatest difference was observed in galactose content. ©1997 SCI  相似文献   

3.
Twelve sunflower (Helianthus annuus L) cultivars grown in Spain were analysed and tested in experiments with rats. The dehulled seeds contained an average of 32.2 MJ kg−1 dry matter (DM) gross energy, 653 g kg−1 DM fat, 60 g kg−1 DM total non-starch polysaccharides (NSP) and 6 g kg−1 DM Klason lignin. The sunflower seed hulls contained 20.2 MJ kg−1 DM gross energy, 53 g kg−1 DM fat, 562 g kg−1 DM total NSPs and 239 g kg−1 DM Klason lignin. The sunflower samples were dehulled and partially defatted (to ∼17% fat) and included in diets for rats. The dehulled, partially defatted samples contained on average 74.6 g nitrogen kg−1 DM and 1.409 mg g−1 phenolic compounds (chlorogenic acid + caffeic acid + derivative 1 + derivative 2) varying from 0.677 to 2.847 mg g−1. Groups of five growing rats were fed diets (9.38% crude protein) containing one of the sunflower cultivars as the only source of protein. Apparent ileal and faecal digestibilities were determined by using an indigestible marker (Cr2O3) and faecal digestibility based on total faecal collections. Apparent ileal, caecal and faecal digestibilities of organic matter were 81.2–91.5% (P = 0.05), 95.8–97.1% (P = 0.005) and 94.7–95.3% (P = 0.94) respectively. The apparent faecal digestibilities of DM, energy and protein (N × 6.25) were 93.2–93.8%, 93.5–94.3% and 81.6–84.3% respectively with no differences among cultivars. Biological value (BV) ranged between 63.8 and 73.2% (P = 0.0001) and net protein utilisation (NPU) between 59.9 and 69.5% (P = 0.0001). BV and NPU were positively correlated with lysine and threonine contents, but no correlation with the analysed phenolic compounds was detected. © 1999 Society of Chemical Industry  相似文献   

4.
The effect of particle size of whole meal rye bread on the apparent digestibility of macro-nutrients, non-starch polysaccharides (NSP) and energy, the energy value of rye NSP and on faecal weight was studied in balance experiments in seven young women. The whole meal breads were prepared from one single batch of rye milled to two different particle sizes (coarse bread: 50% of particles >2 mm, 90% >1 mm; fine bread: 86% of particles <0·5 mm, 58% <0·2 mm). Two diets containing either coarse (350 g day−1) or fine (377 g day−1) whole meal bread and a low fibre control diet were consumed for 3 weeks each in a 3×3 cross-over design. Relative to the low fibre control diet, digestibility of protein, NSP and energy was significantly lower for the diets containing the whole meal breads. Digestibility of fat was the same for all diets. Partial digestible energy value for each g of NSP from coarse and fine whole meal rye bread was calculated to be −3±7 and 1±5 kJ, respectively. There were no differences between coarse and fine whole meal rye bread in the effects on the parameters measured with the exception on faecal wet weight, which was higher for the coarse bread diet.  相似文献   

5.
The hulls and cotyledons from three Western Australian cultivars (Gungurru, Yorrel and Danja) of Lupinus angustifolius, all of low alkaloid content, were analysed separately for their carbohydrate content and composition. Only minor differences in composition between these three cultivars were observed. More notably, the cotyledons of all the cultivars contained levels of non-starch polysaccharides (NSP), ranging from 290 to 310 g kg?1 dry weight considerably higher than had been measured previously in cultivars of this species. Galactose, arabinose and uronic acid residues accounted for approximately 67%, 13% and 10%, respectively, of the cotyledon NSP. Although only a small proportion of the cotyledon NSP is soluble, a much larger proportion could be extracted with hot EDTA treatment. The oligosaccharide content of the cotyledons ranged from 74 to 80 g kg?1 dry weight. Cotyledons had very low contents of cellulose, lignin and starch. Hulls consisted predominantly of NSP, with values ranging from 856 to 891 g kg?1 dry weight. Glucose, xylose, uronic acids and arabinose were the principal sugar residues present reflecting the compositions of the major constituent polysaccharides, cellulose, hemicelluloses and pectins. Only low levels of lignin were measured in hulls. Cotyledon NSP and hulls from these cultivars may have considerable value as sources of dietary fibre in the human diet.  相似文献   

6.
The effect of supplementation of palm kernel oil in periwinkle flesh and palm kernel cake‐based diets on carcass characteristics and meat quality of broilers was evaluated. Birds were assigned to five dietary treatments in a completely randomized design. The first diet, which was the control, contained 20 mg kg?1 fishmeal but it did not contain palm kernel cake and periwinkle flesh. The second diet contained 20 mg kg?1 fishmeal, 250 mg kg?1 palm kernel cake but no periwinkle flesh. The third diet contained 60 mg kg?1 periwinkle flesh, 250 mg kg?1 palm kernel cake and no fishmeal. Present in the fourth diet were 250 mg kg?1 palm kernel cake, 30 mg kg?1 periwinkle flesh, no fishmeal and 20 mg kg?1 palm kernel oil. Similarly, the fifth diet contained 250 mg kg?1 palm kernel cake, 30 mg kg?1 periwinkle flesh, no fishmeal and 40 mg kg?1 palm kernel oil. Carcass measures and cuts were significantly influenced (P < 0.05) by dietary treatments. Diets 2, 3 and 5 gave significantly higher plucked dressed weights, total edible meat and total bone weights, respectively. Also carcass cuts were significantly increased (P < 0.05) in birds on periwinkle and palm kernel oil diets, with abdominal fat being highest in diet 5 having 40 mg kg?1 palm kernel oil. However, proximate composition, physical and sensory properties were not significantly (P < 0.05) influenced by dietary treatment. Results showed that carcass characteristics improved as compared to the control group. Copyright © 2005 Society of Chemical Industry  相似文献   

7.
By-products arising from vegetable processing activities have been assessed in relation to their potential application as sources of dietary fibre supplements in refined foods. Sources used were fresh cauliflower, globe artichoke and chicory witloof. Non-starch polysaccharide (NSP) content and composition of selected parts of each plant source have been measured from alcohol insoluble residues (AIR) and by fibre analysis, complemented by methylation analysis to characterise structural features of component polysaccharides. Results indicate that cauliflower upper stem NSP was similar to the floret (∽25 g kg−1 fresh weight) and each was rich in pectic polysaccharides. Cauliflower lower stem was enriched in NSP (∽66 g kg−1) due mainly to cellulose and xylan deposition, which resulted in a proportionate decrease in pectic polysaccharides. Artichoke stem (∽38 g NSP kg−1) was similar to the receptacle (∽34 g NSP kg−1) but bracts were heavily lignified. Chicory root and leaf bud were each rich in pectic polysaccharides but NSP content was much higher in the root (∽46 g kg−1) than the leaf (∽8 g kg−1). Results indicate that processing by-products, eg cauliflower upper stem, artichoke stem and chicory root, could prove useful as sources of pectic polysaccharide-rich supplements. However, polysaccharide composition and glycosidic linkage pattern also identified important structural differences between sources. The importance of ‘fibre type’ when considering development of food supplements is discussed. © 1998 SCI.  相似文献   

8.
Experiments with Wistar rats were performed to study the digestibility of nutrients and nitrogen (N) utilization of dried and toasted (130°C, 3–4 min) peas (Pisum sativum spp hortense) cultivar Solara, harvested in two different years. Diets were formulated containing 111–128 g kg-1 dietary fibre and ∽170 g kg-1 crude protein with peas as the sole source of polysaccharides and N, and unsupplemented or supplemented with antibiotics (Nebacitin) to reduce the gastrointestinal microflora. In one of the harvests, the digestibility of starch was almost complete and unaffected by addition of Nebacitin. In the other harvest of peas, starch digestibility was very high (98·6–99·3%) in the rats with normal microflora, and reduced to 96% by addition of the antibiotics. The digestibility of non-starch polysaccharides (NSP) was 71·2–72·8% in one harvest and 73·6–76·4% in the other. The digestibilities decreased by addition of Nebacitin (25·7–38·5%). Toasting affected the digestibility of some NSP monomers, but with different tendencies in the two harvests. The N metabolism was affected by toasting in one harvest, while there was no effect in the other. The effect of toasting on BV of peas and the availability of lysine were studied in one of the pea harvests. No effect was observed. © 1997 SCI.  相似文献   

9.
By applying several differential staining techniques and light microscopy, the structure and composition of Chilean hazelnut (Gevuina avellana) seeds were analysed. The structure of the G avellana seed is very simple, with a thin, heavily lignified seed coat and two voluminous cotyledons. The embryo food reserves are uniformly distributed over the cotyledon cells. The cell wall polysaccharides were recovered from the alcohol‐insoluble residue by mild treatment with warm chlorite solution and sequential extraction with alkali solutions of increasing concentration. FT‐IR spectra in the 1200–850 cm?1 region were used together with chemometric techniques to distinguish the hemicellulosic and pectic polysaccharides in the extracts. The most abundant extracts were fractionated by graded precipitation in ethanol. A xyloglucan was identified by 1H and 13C NMR as the major hemicellulosic polysaccharide, with a sugar composition of 4Glc:3.5Xyl:1Gal:0.5Fuc. The hazelnut cell walls are composed of equivalent amounts of pectic polysaccharides, xyloglucans and cellulose. © 2003 Society of Chemical Industry  相似文献   

10.
The effects on organ relative weights (g per 100 g bw) and plasma amino acid concentrations of diets based in legume (faba bean (Vicia faba), lupin (Lupinus angustifolius), chickpea (Cicer arietinum) and soybean (Glycine max)) seed meals as the only source of protein were studied with growing rats using lactalbumin or casein as controls. Also, legume seed meal extracted globulins were included in control diets replacing lactalbumin to produce legume globulin‐based diets, and legume residue fractions, containing most of the starch and/or insoluble fibre (NSP+lignin) from the seed meals, were included in control diets to reach the same amounts present in whole legume seed meal diets. All experimental diets were formulated to contain the same amounts of protein (100 g kg−1) and energy (15.5 kJ g−1), and were supplemented with essential amino acids. Compared with lactalbumin, higher relative weights of gastrointestinal sections were determined in rats fed legume seed meals or their corresponding residue fractions. On the contrary, spleen relative weight was lower in rats fed diets containing lupin, chickpea or soybean meals or extracted globulins, while residue fractions had no effect on it. Thymus relative weight was also lower in rats fed whole chickpea seed meal or any of the extracted legume globulins. Except for chickpea meal, animals fed legume‐ or legume protein‐based diets had lower liver relative weights than controls. Lower proportions (mg g−1 tissue) of glycogen, and lower total protein and RNA, were also determined in the livers of rats fed lupin seed meal. Free plasma concentrations (mM litre −1) of glycine, histidine and arginine were higher, and threonine, leucine and lysine were lower, in rats fed diets based in all legume seed meals of their respective globulin proteins. The possible reasons and implications of these results are discussed. © 1999 Society of Chemical Industry  相似文献   

11.
An extraction procedure is described for the complete solubilisation and fractionation of non-starch polysaccharides (NSP) from barley and malt, using ethanol, water and 4-methylmorpholine-N-oxide. Important structural features of the NSP are preserved with this non-destructive procedure. The fractionation method enables the investigation of structural features of NSP fractions and of NSP breakdown during malting.  相似文献   

12.
The chemical composition of chaya (Cnidoscolus spp) leaves, as a promissory edible tropical shrub for both humans and animals was evaluated. The chemical composition of C aconitifolius did not differ significantly with age of regrowth, with the exception of ether extractives and the oxalic acid content. Galactose, glucose and xylose were the most important sugars found in the insoluble fraction and, galactose and uronic acid were the main components in the soluble portion of non‐starch polysaccharides (NSP). There was a total content of 197.2 g kg?1 NSP, of which 68.72 and 31.26% corresponded to the insoluble and soluble components respectively. The amino acid composition of C aconitifolius ranged from 0.416 for lysine to 0.641 for valine relative to their contents in soyabean meal. Nevertheless, without exception, the concentrations of all the essential amino acids in C aconitifolius were higher than the corresponding values in alfalfa, a fibrous foodstuff widely acceptable in diets for farm animals. Copyright © 2003 Society of Chemical Industry  相似文献   

13.
花生粕存在黄曲霉毒素B_1(AFB_1)易超标、非淀粉多糖含量高和蛋白质品质不佳等缺陷,利用微生物(枯草芽孢杆菌、酿酒酵母、乳酸片球菌)发酵结合复合酶制剂处理花生粕,可以综合改善其饲用品质。研究表明:处理后花生粕中AFB_1的去除率为94.6%,非淀粉多糖含量由30%降低至10.5%,蛋白质含量由47.8%提高至61.5%,大分子蛋白明显降解为小分子蛋白,小肽含量由5.36%提高至25.21%,必需氨基酸总量提高了19.67%,乳酸含量由0.7%提高至2.8%。经过生物技术法处理,花生粕的饲用品质得到了明显改善。  相似文献   

14.
Leeks were cultivated under conditions differing in level of nitrogen (N) supply (100 kg N ha-1, 160 kg N ha-1, 220 kg N ha-1, 280 kg N ha-1), level of water supply (normal, low) and time of harvest (September, October, November). Based on chemical analysis and balance studies on rats the nutritive value of the 26 batches of leek was determined. The protein content of the leeks increased progressively from 90 g kg-1 DM to 163 g kg-1 DM with N-supply. This increase in protein was associated with a reduction of all essential amino acids (g per 16 g N) and, subsequently, a reduction of the biological value. Protein and energy digestibilities increased with level of N-supply. Leeks harvested in September had a higher protein content, but had at the same time the lowest biological value as compared to leeks harvested in October or November. This was due to a lower content of essential amino acids (g per 16 g N) in leeks harvested in September as compared to leeks of later harvest. Only small differences between the two levels of water supply were observed in the chemical composition of the leeks. The content of non-starch polysaccharides (NSP) was rather high in all samples of leek (approximately 240–280 g kg-1 DM) and appeared to be unaffected by the growth conditions applied in the investigation. Soluble-NSP constituted approximately half of the total NSP. © 1997 SCI.  相似文献   

15.
The peach palm (Bactris gasipaes Kunth) is the starchy fruit of a palm tree widely cultivated in Central and South America. The present study aimed at determining its chemical composition and its nutritive value in rats. The average chemical composition of 17 samples was as follows: 410 g kg?1 water and, in g kg?1 of dry matter (DM), 54 g crude protein, 114 g oil, 39 g neutral detergent fibre, 716 g starch, 21 g sugars and 18 g ash. The main variability was observed for the oil (60–180 g kg?1 DM) and starch (590–780 g DM) contents. The proteins contained, on average, in g kg?1 of proteins, 49 g lysine, 13 g methionine, 19 g cysteine, 39 g threonine and 7 g tryptophan. The mineral fraction contained, per kg DM: 1.0 g Ca, 0.8 g P, 0.6 g Mg, 0.3 g Na, 44 mg Fe, 4 mg Cu and 10 mg Zn. The digestibility of four peach palm genotypes was determined in rats fed a diet composed of 350 g kg?1 of peach palm and 650 g of a control diet based on maize and soybean meal. The digestibility of DM, energy, starch and protein of peach palm alone reached, on average 91, 87, 96 and 95%, respectively. No difference was observed between varieties, except for starch (p < 0.05). On average, peach palm contained 51 g of truly digestible protein kg?1 DM and 3.691 kcal digestible energy kg?1 DM. A growth trial was also carried out for 1 month on rats (initial weight: 78 g) fed a diet containing 0, 200, 400, 600 or 800 g peach palm kg?1, at the expense of a diet composed of maize starch and casein. The growth rate of the rats decreased (p < 0.05) as the peach palm concentration increased. The growth decrease was due to a decrease (p < 0.05) in DM intake and to the lower quality of the peach palm protein. It is concluded that peach palm is mainly an energy source for humans and animals. It is poor in protein and minerals but can be consumed in large amounts. Copyright © 2005 Society of Chemical Industry  相似文献   

16.
The dietary fibre fractions in two winter cultivars each of hulled oats and naked oats grown on three sites under different agronomic conditions in two years were studied. Overall, soluble non‐starch polysaccharides (NSP) represented some 540 g kg−1 of total NSP, and this did not vary greatly among cultivars. There was a significant (P < 0.001) positive relationship between total and soluble NSP. Within cultivars there was much greater variability in the concentrations of β‐glucans than in soluble NSP, and overall there was no relationship between the concentrations of the two related fractions. Oat cultivar and factors such as year and site where grown significantly (P < 0.01) affected soluble NSP contents. There were some indications that environmental factors such as temperature, rainfall and sunshine hours may have been responsible for the apparent effects of site and year. On a dehulled basis, traditional hulled cultivars contained significantly (P < 0.05) more β‐glucans than the naked types, and the results suggest that selection of oats for dietary or plant‐breeding purposes should be based on β‐glucan rather than soluble NSP concentrations. © 2000 Society of Chemical Industry  相似文献   

17.
The effects of gamma irradiation from a 60Co source (10 and 20 kGy), dry heating (121 °C for 10, 20 and 30 min), autoclaving (121 °C at 103.5 kPa for 10, 20 and 30 min) and their combination on chlorogenic acid, soluble protein, available lysine and in-vitro protein digestibility of sunflower meal were studied. The moisture content of the raw sample was 78 g kg−1 as is and on a dry matter basis. The meal contained 26.7 g kg−1 chlorogenic acid, 330 g kg−1 crude protein, 78.5% soluble protein and 2.63 g 16 g N−1 available lysine. Digestibility of raw meal was 81.5%. Chlorogenic acid, soluble protein and available lysine of raw meal decreased during dry heating, autoclaving and radiation processing. The digestibility was significantly affected by processing method (P < 0.05), as well as by the time of dry heating and autoclaving. The influence of combination methods revealed that irradiation alone had a little effect on chlorogenic acid and in-vitro protein digestibility. Autoclaving plus irradiation up to 20 kGy markedly improved the digestibility (90%). Therefore, the results suggested that the combination of autoclaving for 10 min plus irradiation up to 20 kGy has a beneficial effect on the protein quality of sunflower meal with little effect on its content of soluble protein, available lysine and markedly reduced chlorogenic acid by 87%, more than other processing methods. © 1999 Society of Chemical Industry  相似文献   

18.
Breadfruit (Artocarpus communis) meal was found to contain (g kg dry matter) 59 crude protein, 14 crude fat, 59 crude fibre, 34 ash and 834 available carbohydrates. The amino acid composition of breadfruit meal (BFM) compared closely with that of maize. The nitrogen-corrected apparent metabolisable energy value of BFM was determined to be 13.89 MJ kg?1 dry matter. Two trials were conducted to evaluate the feeding value of BFM in broiler diets. In trial 1. BFM was included in broiler starter and finisher diets at 0, 125 and 250 g kg?1 replacing maize. In trial 2, BFM was incorporated in broiler starter diets at 0, 200 and 400 g kg?1 replacing maize. The results indicate that BFM supported broiler performance as efficiently as maize at all dietary levels tested.  相似文献   

19.
Red clover was harvested at five different stages of maturity during primary growth and separated into leaves, petioles, stems and flowers. The contents of extractives, crude protein, starch, non-starch polysaccharides, and non-starch polysaccharide constituents, and the in vitro degradability, were determined in the botanical fractions. Chemical analysis of the in vitro residues revealed that the degradability of crude protein was around 80% in all fractions at all harvest times whereas in most cases the degradability of non-starch polysaccharides and non-starch polysaccharide residues was highest in the leaf fractions, intermediate in the petiole fractions and lowest in the stem fractions, with only small changes occurring due to development and maturation during the investigated period. Glucose and xylose were the least degraded non-starch polysaccharide residues in all fractions.  相似文献   

20.
Non-starch polysaccharides (NSP) were obtained from deproteinated nettle biomass and characterised for pectin, hemicellulose and cellulose content. The nettle deproteinated biomass (NDB) represents 52·4% (w/w) of the dry nettle biomass and contains 695·5 g kg?1 NSP. The pectin, hemicellulose and cellulose amounts are 196·7, 334·5 and 128·5 g kg?1, respectively. The high content of pectins and hemicelluloses may make the NDB an important source of dietary fibre. The NSP were hydrolysed by crude enzymatic preparations and both their biodegradability and the amount of simple sugars released have been determined. In the best conditions more than 40% of the NSP were hydrolysed with a considerable increase of sugars. These enzymatic treatments could be used to improve the feed digestibility of the biomass or to obtain bioenergetic compounds by fermentation of the hydrolysed sugars.  相似文献   

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