Effect of processing on nutrient composition and anti-nutritive substances of African locust bean (Parkia filicoidea) and baobab seed (Adansonia digitata)

The effects of various processing techniques on nutrient composition and anti-nutritional factors in baobab seeds (Adansonia digitata L.) and locust beans (Parkia filicoidea L.) were investigated. The methods used for processing include boiling in water, acid or alkali and fermentation. Using the water treated samples as controls, there were slight decreases in protein and carbohydrate contents of the fermented and alkali-treated meals. However, an increase in extractable oil content was observed in acid, alkali and fermented samples. The alkali treatment appeared to be the most effective method for reducing trypsin inhibitor and tannin contents and has the additional advantage of improving the protein digestibility.     

Nutritional studies on rats and fish (carp Cyprinus carpio) fed diets containing unheated and heated Jatropha curcas meal of a non-toxic provenance

Unheated and heated (121 ^°C, 66% moisture; 15, 30 and 45 min) Jatropha meals of non-toxic provenance from Veracruz state in Mexico were evaluated using rats and fish. With rats, the weight gain was highest for the casein diet followed by heated (30 min; only this treatment was studied using rats) and unheated Jatropha meal containing diets. The protein efficiency ratio (PER) for unheated and heated Jatropha meal containing diets was 37 and 86%, respectively, of the casein diet. On the other hand, the body weight gain, PER and feed conversion ratio of fish were statistically similar for unheated and heated (15, 30 and 45 min) Jatropha meal containing diets fed for a period of 35 days. Although these parameters were statistically similar for the unheated and heated Jatropha meal containing diets, the body weight gain, PER and protein productive value were highest and the feed conversion ratio lowest with 15 min heated Jatropha meal, suggesting that the heat treatment for 15 min is optimal for the meal. Trypsin inhibitor and lectin activities decreased drastically (>83 and 99%, respectively) after 30 and 45 min of heat treatment and after 15 min, the residual lectin activity was negligible and the residual trypsin inhibitor activity was 34%. These results, together with the nutritional parameters investigated, imply that Jatropha trypsin inhibitors and lectins do not have any adverse effects on carp at least up to 35 days of feeding. The nutritional value of Jatropha meal of the non-toxic provenance is high, and potential exists for its incorporation into the diets of monogastrics, fish and possibly humans.     

Nutritive value and effect of blanching on the trypsin and chymotrypsin inhibitor activities of selected leafy vegetables

Proximate composition, energy, mineral and vitamin contentsand the effect of blanching methods and times on the trypsinand chymotrypsin inhibitor activities were studied usingcabbage, collard, turnip, peanut, and sweet potato leaves.Results of this study indicated that, crude protein, crudefat, carbohydrate and ash contents were in the range of 15.5–25.6%, 1.4–6.5%, 60.4–73.1% and 6.8–7.5%,respectively. Total dietary fiber was lowest in cabbage (28.2 g/100 g) and highest in the collard leaves (43.1%)while energy content per 100 g of vegetables was highestin sweet potato leaves (402 kcal) and lowest in cabbage(379 kcal). The mineral content per 100 g of vegetableswere in the range of 33.4–249.8 mg, 241.2–471.2 mg,12.1–75.1 mg, 14.9–98.9 mg, 0.5–3.5 mg and 0.9–3.1 mgfor Ca, K, Na, Mg, Fe and Zn, respectively. For ascorbicacid, riboflavin, thiamin and total carotenoids, concentrations in 100 g of vegetables were in the range of45.1–112.7 mg, 0.2–0.3 mg, 0.3–0.8 mg and 2.0–7.3 mg,respectively. The trypsin inhibitory activity per gram ofthe vegetables was highest in collard (60.1 TIU/g) andlowest in peanut leaves (41.0 TIU/g). Chymotrypsin inhibitoractivity was highest in the peanut (69.6 CIU/g) but lowestin the collard leaves (48.0 CIU/g). Both trypsin and chymotrypsin inhibitor activities were significantly (p<0.05) reduced by most of the treatments in eitherthe conventional or microwave blanching methods. In the conventional blanching method, trypsin inhibitor activitywas reduced by 0.5, 6.8, 11.9, 9.0 and 19.3 percent in cabbage, collard, turnip, sweet potato and peanut leaves,respectively, when the vegetables were blanched for 2.5 minutes but after blanching for 10 minutes, the trypsininhibitor activity was reduced by 29.7, 34.9, 54.3, 52.3and 65.6 percent in cabbage, collard, turnip, sweet potatoand peanut greens, respectively. For the microwave ovenblanching, trypsin inhibitor activity was reduced by 3.8,3.3, 32.7, 5.0 and 9.5 percent in cabbage, collard, turnip,sweet potato and peanut leaves, respectively when thevegetables were blanched for 30 seconds. When blanched for60 seconds, trypsin inhibitor activity was reduced by 16.2,45.8, 46.2, 51.0 and 42.4 percent in cabbage, collard, turnip, sweet potato and peanut greens, respectively.Similar trends in the reduction of chymotrypsin inhibitoractivity were observed when the vegetables were conventionally blanched for 2.5, 5 and 10 minutes andwhen blanched by microwave oven for 30, 45 and 60 seconds.Based on the results of this study, the vegetables weregood dietary sources of minerals, vitamins, carbohydrateand proteins. Also, blanching was an effective method forreducing the trypsin and chymotripsin inhibitor activitiesin the leafy vegetables, however, further investigation onthe heating times for both conventional and microwaveblanching methods is suggested.     

超早期断奶应激对仔猪消化酶活性的影响初报

试验选用两窝１４ 日龄杜×（ 大×长） 三元杂交商品猪,每窝１０ 头,每窝仔猪按体重平均分为断奶处理组和哺乳对照组,每组两个重复（ 栏） ,每栏５ 头猪。分别于断奶后第０（１４ 日龄） 、２ 、４ 、６ 、９ 天从每栏内随机抽取一头猪,屠宰后取胰腺和空肠内容物样品,测定胰蛋白酶、淀粉酶及脂肪酶活性。试验结果表明,断奶应激不同程度地降低了仔猪胰腺和空肠内容物中胰蛋白酶、淀粉酶和脂肪酶活性。随着断奶后时间的推移和采食量的增加,断奶仔猪空肠内容物中胰蛋白酶、脂肪酶以及胰腺中淀粉酶活性得以恢复并呈上升趋势。     

抗豆象绿豆胰蛋白酶抑制剂活性及理化性质

以4个抗豆象绿豆品系B18、B20、B24和A22为试材,以感虫绿豆品种晋绿1号为对照,研究了不同绿豆中胰蛋白酶抑制剂活性及其在高温、酸碱及超声波下绿豆的胰蛋白酶抑制剂稳定性。结果表明,4个抗豆象绿豆品种胰蛋白酶抑制剂活性均显著高于对照感虫品种,且均与对照在0.01水平差异极显著,其中B18活性最高,高达70.2TI U g–1,B20和A22活性次之,B24活性最差,但仍高达55.2 TI U g–1。4个抗豆象绿豆品种在不同温度、不同p H和不同振幅超声波下,残余活性均比对照高,且残余活性均随温度升高、温浴时间延长而降低,p H在2~12之间,随p H值的升高,残余活性均呈现先升高后降低的趋势,且p H值为6~8之间残余活性最高,残余活性也随超声波辐射强度升高、时间延长而降低,且4个抗虫品种中B18的耐高温性、耐酸碱性和耐辐射性最强,B20次之,B24的耐高温性、耐酸碱性最差,A22耐辐射性最差,说明在不同温度、p H和超声波处理后,B18、B20是抗豆象绿豆胰蛋白酶抑制剂残余活性保存最高的2个品种,应用价值较大。     

大豆胰蛋白酶抑制剂的研究进展

从结构、毒理学分析和灭活方法3个方面对国内外近年来对大豆胰蛋白酶抑制剂的研究进展进行了综述。     

米根霉菌体对胰酶粉浸提液吸附脱色研究

[目的]研究1株米根霉菌体对胰酶粉浸提液中色素的生物吸附作用。[方法]分别考察菌体预处理、菌体添加量、菌球吸附粒径、溶液初始值、吸附时间、温度等对生物吸附脱色的影响。[结果]米根霉菌体对胰酶粉浸提液中色素的最佳脱色条件为：0.2 mol/L NaOH溶液热处理20 min,添加菌体量2%,菌体粒径0.6 mm,溶液初始pH值6.0,吸附脱色时间160 min、10℃,脱色率在89.5%以上,激肽原酶活性损耗小。[结论]米根霉菌体对胰酶粉浸提液脱色效果显著。     

Effects of heat treatment and germination on trypsin and chymotrypsin inhibitory activities in sorghum (Sorghum bicolor (L.) Moench) seeds

There was no appreciable change in proteinase inhibitory activity in sorghum upon dry heat treatment. However, moist heating reduced trypsin and chymotrypsin inhibitors to a greater degree. Germination (5 days) brought about complete reduction in proteinase inhibitory activity.     

胰酶对猪流行腹泻病毒纤突蛋白作用的研究进展

猪流行性腹泻病毒（PEDV）的分离及纤突（S）蛋白是最近几年来研究的热点。本文结合胰酶对PEDV S蛋白裂解作用促进病毒分离的国际最新研究进展,并对S蛋白及其功能、胰酶改变S蛋白构象、胰酶触发S蛋白融合机制等方面进行综述,以期为PEDV的防控提供参考。     

Heritability of Exocrine Pancreatic Insufficiency in German Shepherd Dogs

Background: Several studies have revealed that exocrine pancreatic insufficiency (EPI) is an inherited disease in German Shepherd Dogs (GSDs). Pedigree analyses have suggested an autosomal recessive inheritance model. Objective: Test mating of 2 dogs with EPI. Animals: A sire and dam purebred GSD both with EPI and a litter of 6 puppies. Methods: Test mating and long‐term follow‐up of offspring. The pancreas was biopsied via laparotomy on 26 occasions. Serum trypsin‐like immunoreactivity was measured. Study was approved by Animal Ethics Committee. Results: During the 12‐year study period only 2 of the 6 offsprings developed pancreatic acinar atrophy (PAA). In 1 puppy, end‐stage PAA and in the other puppy partial PAA was diagnosed. Conclusions and Clinical Importance: PAA is not a congenital disease in GSDs. This study provided evidence that PAA is not inherited in a simple autosomal recessive fashion.