Malt sprouts as a source of supplemental protein for ruminants

Nitrogen solubility, ruminal degradation, and amino acid composition of pelleted malt sprouts, pelleted corn gluten feed, and soybean meal were studied. Four rumen-cannulated steers were fed diets containing 45% pelleted malt sprouts or 45% pelleted corn gluten feed in a 2 X 2 crossover design with 15-d periods. Ruminal degradation of dry matter and nitrogen from malt sprouts or corn gluten feed was estimated by disappearance of these components from polyester bags after 1, 2, 3, 4, 6, 8, 10, 12, 16, or 24 h of in situ fermentation. For comparison, degradation of soybean meal after 2, 4, 8, or 24 h was measured. Malt sprouts had less soluble nitrogen than corn gluten feed, but available crude protein contents were similar. Malt sprouts dry matter was degraded more slowly than was corn gluten feed dry matter. Nitrogen degradation rates of the two feeds, after correction for unavailable nitrogen, did not differ. Malt sprouts had higher concentrations of arginine, lysine, and aspartate than corn gluten feed; however, corn gluten feed had higher concentrations of the other amino acids measured. Malt sprouts would be expected to provide more amino acids of feed origin to the lower gut of ruminants, provided passage rates of the supplements are similar.     

Full-fat sunflower seed as a protein source for broiler chicks

The protein quality of hulled full-fat sunflower seed (HFFSS) was evaluated and compared to that of soyabean meal in two experiments with broiler chicks. In the first experiment, PER and NPR indexes were determined. The results showed that, when fed as the sole source of dietary protein (90 g crude protein kg⁻¹ diet), the performance as well as PER and NPR values of chicks fed HFFSS were much poorer than those of chicks fed soyabean meal. The protein quality of HFFSS was improved greatly by lysine supplementation. The PER and NPR values for HFFSS supplemented with 0.2 and 0.4% of L -lysine equalled and even became superior to those estimated for soyabean. In the second experiment, apparent and true ileal digestibilities of nitrogen and amino acids were calculated. The apparent but not the true digestibility of the mean of amino acids was significantly lower (P < 0.01) in HFFSS than in soyabean meal (0.838 vs 0.902 and 0.932 vs 0.957, respectively). The results also showed that lysine from HFFSS was less digestible than that from soyabean meal, the apparent as well as the true digestibility values being lower in the former. © 1999 Society of Chemical Industry     

Nutritional evaluation of the fungus Phycomyces blakesleeanus as a protein source

The quality of the protein of the carotenogenic fungus Phycomyces blakesleeanus Burgeff, strain NRRL 1555 ( - ), was evaluated with rats and observed to have a protein efficiency ratio of 1.4. The limiting amino acids were tryptophan, sulphur-containing amino acids, lysine and isoleucine. Upon incorporation into diets containing 100 g kg⁻¹ protein the proportions of the above mentioned amino acids of the optimal recommended dietary allowances for growing rats were 33.0%, 57.4%, 74.5% and 87.2% respectively. Furthermore, the fungal protein was found to contain an excess of histidine about eight fold more than the recommended dietary allowance for growing rats. Some safety aspects were examined and, although the fungus was consumed in high dietary concentrations, 242 g kg⁻¹ of the diet, no pronounced toxicological effects were observed.     

Vicia faba beans vs. soyabean meal as a source of protein

The protein value of raw, heated and shelled Vicia faba beans (VFB) was compared with that of heated soyabean meal (HSB) when fed at 10 and 15% protein levels to rats of both sexes. While females grew equally well on VFB and HSB diets containing 15% protein, males fed VFB grew more slowly than those fed HSB at the two levels of protein in the diets (the difference being smaller on the 15% protein diet). The lower N utilisation of VFB seems to be the main reason for the differences in the growth response. Shelling improved the nutritive value of VFB, while autoclaving affected it adversely. The trypsin inhibitors of the VFB were not destroyed by autoclaving.     

Proteins of Brassicaceae oilseeds and their potential as a plant protein source

Among the commercially cultivated Brassicaceae (Cruciferae) plants, Brassica juncea, Brassica napus, Brassica rapa, and Sinapis alba store significant amounts of oil and protein in the seed. At present, Brassica seed proteins are primarily used for livestock feeding based on the nutritional value. The point of curiosity is whether the present knowledge on the protein structure, biochemical characteristics, nutritive value, and the recovery processes are inadequate to develop Brassica proteins into a usable plant protein source or these proteins are of substandard for uses beyond animal nutrition applications. Cruciferin (11S) and napin (2S) are the predominant storage proteins of Brassicaceae seeds that contribute to different properties and functions. A gamut of information is available on the chemistry, nutritional value, as well as the functionality in foods, and associated non-protein components of canola/rapeseed storage proteins. The intention of this article is to critically review what is known about the predominant storage proteins of commercially produced Brassicaceae seeds relative to the above aspects and identify the knowledge gaps.     

Problems which limit the use of rapeseed meal as a protein source in poultry diets

The occurrence of a ‘fishy’ or ‘crabby’ taint in eggs and liver damage culminating in massive haemorrhage has greatly restricted the commercial utilisation of rapeseed meal as a relatively cheap protein supplement for laying hens in the UK. Recent work on these problems is reviewed. It has elucidated the cause of the taint and identified the rapeseed constituents that are involved. A genetic defect impedes the synthesis of trimethylamine oxidase in susceptible hens and goitrin and tannins inhibit the enzyme. This biochemical lesion severely impairs the metabolism of trimethylamine which is released from sinapine and other dietary sources of choline by enteric bacteria. Consequently, excessive amounts pass into the yolk and produce the taint. Liver haemorrhage is associated with hepatocyte degeneration, abnormalities in the biliary system and the leakage of cellular enzymes into the plasma. The toxic substance(s) responsible has (have) not yet been identified.     

Celery by-products as a source of mannitol

Vegetable by-products have mainly been utilized as a source of dietary fiber and natural antioxidants, but residual vegetables could also be used as a raw material for soluble sugar and polyol extraction. Therefore, two celery residues from the food industry, composed either of stalks alone or stalks plus leaves, were extracted with hot 85% ethanol to solubilize soluble sugars and mannitol. Low-molecular-weight carbohydrates in the extracts were identified and quantified by high-performance liquid chromatography. Both celery residues contained similar amounts of sucrose (5.7-5.9%), but different ratios of hexose (glucose and fructose) to mannitol. Total sugar content and mannitol were higher in the stalks (45.5% and 15.2%, respectively) than in the stalk plus leaf residues (33.9% and 13.3%, respectively). Mannitol represented 33.5-39.3% of the total carbohydrate in celery wastes. The alcoholic extracts from celery residues are proposed as a natural source of mannitol and soluble sugars, which might be used by the food industry. The alcohol-insoluble residue from celery by-products could be further used for the preparation of dietary fiber-rich food supplements.     

Evaluation of calcium lignosulfonate-treated soybean meal as a source of rumen protected protein for dairy cattle

Four Holstein cows fitted with ruminal, duodenal, and ileal cannulae were used in a 4 x 4 Latin square design to measure ruminal protein degradation and small intestinal digestion of diets containing untreated soybean meal or soybean meal treated with heat and either water, xylose, or calcium lignosulfonate. Diets consisting of 40% corn silage, 10% alfalfa cubes, and 50% grain mix, and averaging 16.8% crude protein (DM basis) were fed four times daily. Approximately 50% of the total dietary protein was supplied by the respective soybean meal source. Ruminal protein degradation was 70.6, 69.6, 55.8, and 53.7% for diets containing untreated soybean meal, water-soybean meal, xylose-soybean meal, and calcium lignosulfonate-soybean meal, respectively. Duodenal non-NH3 N flow (g/d) and absorption of non-NH3 N (g/d) in the small intestine were generally not affected by treatment. Duodenal bacterial N flow (g/d) was lower with xylose-soybean meal and lignosulfonate-soybean meal than with untreated soybean meal. Treatment of soybean meal with xylose or calcium lignosulfonate was successful in decreasing ruminal protein degradation. However, it may be necessary to include a source of readily fermentable N in diets that contain protected proteins in order to supply adequate NH3 N for microbial protein synthesis.     

Heat- and lignosulfonate-treated canola meal as a source of ruminal undegradable protein for lactating dairy cows

This experiment used 18 lactating Holstein cows in a 3 x 3 Latin square replicated 6 times to determine the effectiveness of processing with moist heat or moist heat combined with lignosulfonate (LSO3) for increasing the ruminal undegradable fraction of canola meal for use as a protein supplement for lactating dairy cows. Diets were formulated to be isonitrogenous and contained one of 3 forms of canola meal; untreated canola meal (UCM), heat-treated canola meal (HTCM) or heat-and LSO3-treated canola meal (LSO3CM). Total collection of urine and feces was taken from each cow during the last 5 d of each 42-d experimental period. Milk production was greater for cows fed the LSO3CM diet (36.6 kg/d) than for cows fed the UCM diet (34.8 kg/d) but did not differ from cows fed the HTCM diet (35.3 kg/d). Digestibility of crude protein was lower for cows supplemented with LSO3CM and they had reduced concentrations of ruminal ammonia N, blood urea N, and milk urea N compared with cows supplemented with UCM or HTCM. Dry matter intake and apparent digestibilities of neutral and acid detergent fiber were increased in cows fed the LSO3CM diet. Urinary N excretion (as % of N intake) was reduced in cows fed the LSO3CM diet. These results indicate that moist heat combined with LSO3 treatment of canola meal was effective in increasing the proportion of crude protein digested in the lower digestive tract of lactating cows and was therefore used more effectively as a source of protein than UCM or HTCM.     

Liquid egg as an alternative protein source in calf milk replacers

The use of alternative proteins in milk replacer has been evaluated for their ability to decrease the cost of milk replacers without negatively impacting performance of the calf. Three studies were conducted to evaluate the performance of calves fed milk replacer utilizing liquid egg as an alternative protein and to determine the optimal concentration of liquid egg to include in milk replacers. Calves in trials 1 and 2 were assigned to a control diet of all milk protein replacer (MILK) or a diet formulated to contain 5% of the diet (13.5% of the protein) from liquid egg (5% EGG). Calves in trial 3 were assigned to one of four diets: the control (MILK) and 5% EGG diets fed in trials 1 and 2, or diets formulated to contain either 10 or 15% of the diet (27 or 40.5% of the protein) from liquid egg (10% EGG, 15% EGG). For all experiments, milk replacers were formulated to contain 20% protein, 20% fat and were fed at 454 g/d reconstituted to 12% DM. Production of the diets containing egg protein utilized breaker eggs that were pasteurized during manufacturing. Holstein bull calves (n = 44 for experiment 1, n = 38 for experiment 2, and n = 120 for experiment 3), were purchased from an area sale barn. Calves were housed in individual hutches with water available free choice starting on d 0. A commercially available calf starter was offered free choice beginning on d 7 for experiments 1 and 2 and on d 1 for experiment 3. Feed intake, scour scores, and antibiotic treatments were recorded daily. For experiment 1, calves fed 5% EGG had greater weight gains than calves fed MILK. No differences in average daily feed intake were observed. For experiment 2, weight gains tended to be lower with 5% EGG, whereas feed intakes and gain to feed ratios were similar between calves fed MILK or 5% EGG. For experiment 3, as the amount of egg in the diet increased, weight gain decreased in a linear fashion during the milk replacer feeding period, but the decrease in gain was significant only with the 15% EGG diet. These results indicate that egg is an effective alternative protein source to milk protein in calf milk replacers when fed at levels up to 10% of the diet in a conventional feeding program of 0.45 kg per head per day.     

Instant food products as a source of silicon

Silicon is a trace element for humans, and is absorbed from food in the form of orthosilicic acid. Instant food products are part of a constantly growing market of convenience foods, which have not been evaluated yet as sources of silicon. In this study the total and soluble silicon contents in different instant food products were determined by using graphite furnace atomic absorption spectrometry (GF-AAS). A selection of instant products commercially available in Wroclaw were analyzed: soups, main courses, coffee drinks, jellies and puddings. Total silicon contents in soups, main courses and coffee drinks ranged widely and reached the values: 0.10–30.20, 0.63–37.91 and 0.21–13.37 mg/serving, respectively. These products contained 0.05–1.26 mg of soluble silicon per serving. The total silicon content in jellies and puddings did not exceed 0.36 mg and 2.42 mg/serving, respectively. Among the analyzed desserts the highest level of soluble silicon was found in chocolate puddings: 0.36–0.41 mg/serving. The silicon level in servings of the studied instant products when prepared with the appropriate amount of water was also estimated. The mean content of silicon determined in samples of drinking water from Wroc?aw and the vicinity, which was used for the estimation, amounted to 7.09 mg/l. The total silicon content in ready-to-eat products ranged from 1.32 to 39.21 mg/serving. In conclusion, some of the analyzed instant foods contained very high amounts of silicon, however the content of the soluble, and hence available, form of this element was low.     

玉米秆作为纤维原料和能源的研究

最近全球石油价格上涨,刺激了木素到能量的转换步伐。用两段酸水解方法将阔叶木的水解木素馏分转化为可发酵生产酒精的糖类。事实上,几家公司和研究机构正在研究通过酸水解和酶化木塑的方法生产出可发酵生产酒精的糖。在此过程中,biomass需要磨成细小碎片来提高酸水解或酶化的得率,特别对于能量密集的木材。     

Chlorella viruses as a source of novel enzymes

A special advantage has been conferred upon Chlorella cells as tools in biotechnology when viruses (Phycodnaviridae) infecting Chlorella cells were discovered and isolated. The viruses are large icosahedral particles (150-200 nm in diameter), containing a giant, 330-380 kbp long, linear dsDNA genome. Recently, the nucleotide sequence of the 330,740-bp genome of PBCV-1, the prototype virus of Phycodnaviridae, was determined, and up to 702 open reading frames (ORFs) were identified along the genome. The possible genes present include those encoding a variety of enzymes involved in the modification of DNA, RNA, protein and polysaccharides as well as those involved in the metabolism of sugars, amino acids, lipids, nucleotides and nucleosides. Many of these genes are actually expressed during viral infection, with functional enzymes detected in the host cytoplasm or incorporated into the virion. The successful utilization of these viral enzymes as various DNA restriction and modification enzymes (Cvi enzymes) that are now commercially available is well documented. Also noteworthy are virion-associated chitinase and chitosanase activities that have potentially important applications in the recycling of natural resources. The virions of Chlorella viruses contain more than 50 different structural proteins, ranging in size from 10 to 200 kDa. Some of these proteins may be replaced with useful foreign proteins using recombinant DNA technology. The proteins of interest can be recovered easily from the viral particles, and collected by centrifugation after complete lysis of the host Chlorella cells.