Effect of metal ions on the hydrolytic and transesterification activities of Candida rugosa lipase.
(41/92)
In order to study the effect of metal ions on lipase activity, hydrolytic and transesterification activities of Candida rugosa lipase were investigated in presence of alkali (Na(+) and K(+)), alkaline earth (Ca(+)(2) and Ba(+)(2)) and transition (Cr(+)(3), Fe(+)(3), Co(+)(2), Cu(+)(2) and Ni(+)(2)) metal ions. Maximum enhancement in hydrolytic activity of lipase was observed by Ca(+)(2), and in transesterification activity by Cr(+)(3) and Co(+)(2). The kinetics of the lipase catalyzed transesterification (methanolysis and ethanolysis) reactions were also studied, and the activation energies of methanolysis and ethanolysis were reduced from 10.16 and 10.24 kcal mol(-)(1), respectively, to 5.41 and 7.55 kcal mol(-)(1), respectively, when reactions were performed in presence of Co(+)(2). Thus, in lipase catalyzed transesterification Cr(+)(3) or Co(+)(2) could be added to the assay in order to produce the biodiesel in relatively shorter reaction duration. (+info)
The delivery of cottonseed meal at three different time intervals to steers fed low-quality grass hay: effects on digestion and performance.
(42/92)
A ruminal fermentation trial and a steer growth trial were conducted to evaluate the effects of time interval of cottonseed meal (CSM) supplementation of predominantly meadow fescue grass hay (GH; CP = 6.6%) on nutrient digestion and growth performance of beef steers. The fermentation trial used four ruminally cannulated steers assigned to a 4 x 4 latin square design with dietary treatments of GH fed alone (C) or GH supplemented with 3 g CP/kg BW.75 daily as supplied by CSM every 12, 24 or 48 h. Nylon bags containing GH were inserted into the rumen on d 1 and 2 of each collection period and incubated for 12, 24, 48 and 96 h to measure NDF and ADF degradation. Subsequently, steers were fed Yb-labeled GH and fecal samples were collected to determine particulate passage rate (PR). Dry matter and NDF intake, mean NDF and ADF in situ disappearance and ruminal VFA concentrations were greater (P less than .05) when CSM was fed; however, the delivery of CSM at various times did not affect (P greater than .10) these variables. Supplemented diets tended (P = .08) to have faster PR compared with the C diet. In the growth trial, CSM supplemented steers consumed more digestible DM (P less than .05) and had greater (P less than .05) daily gain compared with C steers. Effects due to time of CSM supplementation were not observed for the variables measured in the present study. (+info)
Ruminal metabolism in nonlactating cows fed whole cottonseed or extruded soybeans.
(43/92)
Five nonlactating Holstein cows (average weight 574 kg) with cannulas in the rumen and duodenum were fed five total mixed diets at 2.14% (DM) of BW for seven 2-wk periods to estimate the ruminal degradation of protein and fatty acids in whole cottonseed (WCS) and extruded soybeans (ESB). Lanthanum was used as an indigestible marker. Ruminal propionic acid (molar proportion) was larger and butyric acid was smaller for WCS diets than for control or ESB diets. Total VFA (mM) and acetic acid (molar proportion) were similar for all diets. Duodenal flow of nonammonia nitrogen (N) was 13% higher for ESB diets than for WCS diets, but was similar for the control and diets with WCS. The percentage of intake protein that was undegraded was 19% higher for ESB diets than for WCS diets. Ruminal and total apparent digestibilities of ADF were not reduced by the addition of oil seed. In conclusion, the protein from ESB was less degraded in the rumen of cows than protein from WCS. The addition of ESB at 12.7% (DM) or WCS at 25.3% of the diet did not reduce the apparent digestibility of fiber. The unsaturated fatty acids in WCS were not protected from ruminal biohydrogenation, presumably due to mastication of the seed coat. (+info)
Effects of cottonseed dietary fiber on metabolic parameters in diabetic rats and non-insulin-dependent diabetic humans.
(44/92)
The objective of this study was to evaluate the effect of gland cottonseed dietary fiber (CSDF) containing 86% dietary fiber (mainly cellulose) on serum glucose levels in diabetic rats and in non-insulin-dependent diabetes mellitus (NIDDM) patients. A diet containing 15% CSDF given to streptozotocin-induced diabetic rats for 30 d tended to reduce the postprandial plasma glucose level curve. Alternatively, CSDF significantly increased fecal weight (15 +/- 3 vs. 5 +/- 2 g; P less than 0.01) and shortened transit time (20 +/- 2.24 vs. 11.2 +/- 0.8 h). CSDF had no effect on body weight and serum lipid levels. Twelve NIDDM subjects were given a meal tolerance test (MTT) with or without CSDF before and after daily supplementation of CSDF (16.5 g) in pita twice a day for a month. Incremental glucose levels were significantly (P less than 0.05) lower at 30, 60 and 180 min after the MTT containing CSDF than in subjects consuming a meal without CSDF. The insulin levels also tended to be lower. The NIDDM subjects tolerated the CSDF well. No flatulence or other side effects were exhibited. Plasma lipid levels remained unchanged. We therefore concluded that CSDF may have a potential benefit in the management of NIDDM. (+info)
Effects of whole cottonseed, cottonseed oil or animal fat on digestibility of wheat straw diets by steers.
(45/92)
Two completely random digestion trials were conducted, each with 12 beef steers (325 kg initial weight), to measure changes in digestibilities of fat and of forage components when fat was added to diets containing 62 to 76% wheat straw. Trial 1 diets contained either no added fat or 6.3% added fat from whole cottonseed (30% of the diet), cottonseed oil or animal fat; diets were formulated to contain equal levels of cottonseed hulls and cottonseed meal. Trial 2 diets contained 0, 2, 4 or 8% added animal fat. In all forms and at all levels, added fat increased apparent digestibility of dietary lipid (P less than .05). However, estimated true digestibility of lipid decreased (from 94 to 71%) as added fat was increased from 0 to 8% (P less than .05). Up to 6.3% added fat increased digestible energy (DE) content of the diet. Fat additions of 2 and 4% increased daily DE intake (P less than .05) and did not depress digestibility of diet components (P greater than .05). Fat additions of 6.3% or greater, either as free fats or as whole cottonseed, reduced (P less than .05) mean acid detergent fiber digestibility from 40 to 28%. In addition to depressing fiber digestibility, 8% added fat reduced (P less than .05) digestibilities of dry matter (from 54 to 47%), organic matter (60 to 52%) and gross energy (60 to 51%). Oil fed as whole cottonseed caused digestibility depressions similar to free fat addition at the same level.(ABSTRACT TRUNCATED AT 250 WORDS) (+info)
Evaluation of corn fiber, cottonseed hulls, oat hulls and soybean hulls as roughage sources for ruminants.
(46/92)
An in situ trial (randomized complete block design) using cows, and a site and extent of digestion trial (Latin square design) using sheep were conducted to study the potential of corn fiber (CF), cottonseed hulls (CSH), oat hulls (OH) and soybean hulls (SH) as roughage sources for ruminants. Two feedlot trials with steers and one with lambs (completely randomized design with factorial arrangements of treatments) were conducted to study the potential of CF and SH as energy supplements relative to corn. In situ rate of ruminal dry matter (DM) disappearance (3 to 36 h) and extent of DM disappearance (36 h) indicated that CF and SH were more fermentable in the rumen compared with OH or CSH, with SH being the most fermentable. Total tract digestibilities of DM, organic matter (OM), neutral detergent fiber (NDF) and acid detergent fiber (ADF) were above 70% for sheep fed CF and SH diets, and were 50% or less for sheep fed OH and CSH diets. A ranking of by-products in terms of nutritive value followed the trend: CF greater than SH greater than OH greater than CSH. Lamb feedlot trial data showed that CF was of similar nutritive value to corn and of higher nutritive value than SH at the 50% level of supplementation. Corn-fed lambs responded better than CF- or SH-fed lambs at the 70% level of supplementation. Data from steer feedlot trials showed that CF was of similar quality to corn and of higher quality than SH. Dramatic differences exist in by-product feed utilization by ruminants. All by-products tested appeared to have some usefulness as dietary components. (+info)
Presence of Aspergillus flavus in developing cotton bolls and its relation to contamination of mature seeds.
(47/92)
Aspergillus flavus spores were dusted onto the involucral nectaries of cotton flowers. The fungus was present in 20 to 58% of the immature bolls harvested 25 or 35 days after anthesis. Among similarly inoculated bolls fully matured either in the field or under sterile conditions at ambient temperatures after excision from the plants, only 3 to 14% contained A. flavus in the seeds. There was no significant difference in the numbers of contaminated bolls between the excised and field-matured treatments. It is concluded that A. flavus is present in developing cotton bolls before dehiscence, but its presence does not ensure infection of mature seeds, and that excision does not reduce A. flavus contamination if the bolls are maintained at ambient temperatures. (+info)
Pathological and toxicological studies of calves fed a high concentration cotton seed meal diet.
(48/92)
Feeding a high concentration of cotton seed meal to young calves resulted in death with lesions compatible with gossypol toxicity. Calves were fed two different commercially prepared rations. Free gossypol concentrations in different lots of the 17% protein ration varied from 250 to 380 ppm, and the 13% protein ration varied from 40 to 240 ppm. Serum sorbitol dehydrogenase elevation was the most consistent clinical pathological finding. The mean serum sorbitol dehydrogenase concentrations for moribund, hospitalized, and clinically healthy calves were 277, 34, and 45 units/liter. The mean for sorbitol dehydrogenase concentration for healthy calves not fed cotton seed meal was 18 units/liter. Gross lesions included severe effusion of a high protein content fluid into the body cavities of most calves, edema of the mesentery, and hepatomegaly. The most consistent histological lesion was severe centrilobular hepatic necrosis. Elevated levels of liver gossypol were demonstrated. The mean liver gossypol concentration for three calves was 41.7 micrograms/g on a wet weight basis. (+info)