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1.
The aim of this work was to investigate the single exposure effect of amoxicillin on the feces composting process and the possibility of its bacterial reactivation by intermittent feeding of feces. The respiratory activity of the bacteria during the process after receiving exposure to several dosages of amoxicillin indicated a decrement of treatment performance, which was caused by the reduction of the initial viable bacterial count and activity brought about by the amoxicillin dosage. The amount of remaining feces was proportional to the initial concentration of amoxicillin, and even though no amoxicillin was detected, no automatic reactivation was observed, either. An intermittent feces feeding test was conducted to reactivate the bacteria. For the 10 and 100microg-amoxicillin/g dry systems, reactivation was observed, but for the 1000microg/g dry, no reactivation was seen. Finally, an intermittent feces feeding test was conducted with sterilized sawdust and the result indicated that the feces acted as a substrate rather than as a bacterial carrier.  相似文献   

2.
From a thoroughly mixed portion of cattle feces with Cooperia sp. eggs, 1-kg artificial pats were placed in 6 buckets containing 6 kg of soil each. Ten dung beetles, Diastellopalpus quinquedens, were added to each of 3 buckets. The remaining 3 buckets served as controls without beetles. When infective parasite larvae (L3) had developed in the cow pats indoors, the following procedure was followed. During occasions of rainfall each bucket was placed outdoors in the center of a wider and higher container. When the rain stopped all buckets were brought indoors, and infective larvae spread by splash droplets during the rain were collected in the containers and counted. After 33 days, the remaining dung on the soil surface in buckets with dung beetles constituted only 38% of that in the controls. Moreover, the number of L3 in feces left on the soil surface in the buckets with beetles was reduced by 88%, presumably due to beetle activity. This may explain the 70-90% reduction in splash dispersal of L3 of Cooperia sp. from cow pats attacked by beetles. The dung-burying activity of the beetles did not result in increased numbers of L3 in the soil under the cow pats, suggesting that many of the parasites in buried feces were destroyed.  相似文献   

3.
Fecal proteins from germfree and conventional rats were isolated. The proteins from the two kinds of feces differed in molecular weight, judging from Sephadex gel filtration and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The conventional feces contained a greater amount of high-molecular-weight and a lesser amount of low-molecular-weight proteins than did the germfree feces. The fecal proteins of both kinds contained carbohydrates. Both feces contained considerable enzyme activity. The germfree feces contained extremely high activity in alkaline phosphatase and leucine aminopeptidase. Both feces showed the same level of trehalase activity. The conventional feces contained higher levels of activity of protease and acid phosphatase than did the germfree feces. Lactase activity was observed only in the conventional feces. The fecal alkaline phosphatase resembled the intestinal enzyme in response to L-phenylalanine inhibition and urea denaturation. From these results it was inferred that the germfree feces contained some of the intestinal proteins and that the conventional feces contained bacterial proteins in addition to intestinal proteins.  相似文献   

4.
Fecal proteins from germfree and conventional rats were isolated. The proteins from the two kinds of feces differed in molecular weight, judging from Sephadex gel filtration and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The conventional feces contained a greater amount of high-molecular-weight and a lesser amount of low-molecular-weight proteins than did the germfree feces. The fecal proteins of both kinds contained carbohydrates. Both feces contained considerable enzyme activity. The germfree feces contained extremely high activity in alkaline phosphatase and leucine aminopeptidase. Both feces showed the same level of trehalase activity. The conventional feces contained higher levels of activity of protease and acid phosphatase than did the germfree feces. Lactase activity was observed only in the conventional feces. The fecal alkaline phosphatase resembled the intestinal enzyme in response to L-phenylalanine inhibition and urea denaturation. From these results it was inferred that the germfree feces contained some of the intestinal proteins and that the conventional feces contained bacterial proteins in addition to intestinal proteins.  相似文献   

5.
Schistocerca gregaria sometimes refuse to lay eggs into the “old sand” that is kept in their cages for several days. We investigated why they rejected the old sand for oviposition. Locusts exclusively laid eggs into new sand when presented together with old sand, indicating that the old sand contained an oviposition-inhibiting (OI) factor. We examined whether this factor was derived from locust feces or fed grass (Bromus catharticus). Locusts laid all eggs into the sand with grass when presented together with sand containing feces. In contrast, few eggs were laid into the sand with grass when clean sand was offered at the same time, suggesting that the OI factor originated from the grass and was concentrated in the feces. The OI factor was efficiently extracted from feces with water compared with ethanol and acetone. OI activity was detected by extraction of feces with water for 1 min, although a longer extraction time yielded higher activity. The water extract of feces retained OI activity after boiling. None of the eggs which were buried in sand containing fecal extract hatched, whereas most of the eggs buried in clean sand or sand containing grass extract hatched, showing a correlation between OI activity and a lethal effect on eggs.  相似文献   

6.
东亚飞蝗不同来源聚集信息素的电生理活性   总被引:6,自引:2,他引:4  
采用触角电位测定仪器测定不同来源的东亚飞蝗Locustamigratoriamanilensis聚集信息素的生理活性 ,结合行为生物测定的结果分析表明 :来源于粪便中的聚集信息素的活性较高 ,同时 ,使用较高极性溶剂抽提制备蝗蝻粪便中的信息素和采用中极性的溶剂制备成蝗粪便中的聚集信息素 ,其信息素的活性均较高 ;利用低极性溶剂从东亚飞蝗粪便中制备得到的聚集信息素的活性较低 ;采用层析柱吸附浓缩飞蝗粪便中自然挥发出的气味和飞蝗体表的气味并进行生物测定后表明 ,其EAG活性普遍较低 ;因此 ,来自于飞蝗粪便中的且采用合适的溶剂抽提制备的聚集信息素 ,具有较高的生物学活性。  相似文献   

7.
Studies were conducted on four giraffe (Giraffa camelopardalis) with diarrhea and three clinically healthy ones. The feces from both healthy and sick animals were examined to determine amylase, lipase and trypsin activity. In the feces of the giraffe with diarrhea a significant decrease of amylase and lipase activity was noted. The trypsin activity remained unchanged. Pancreatic exocrine insufficiency-like syndrome was diagnosed on the basis of laboratory investigations and histopathological examinations. The administration of pancreatic enzyme supplements (Pancreatin; Polfa, Poland) had a noticeable effect on the normalization of clinical state and laboratory data of the giraffe with diarrhea. Determination of amylase and lipase activity in the feces may be helpful in determination of the condition of the pancreas in the course of chronic diarrhea in giraffe.  相似文献   

8.
Non-invasive fecal steroid analyses were used to characterize gonadal activity in the fishing cat (Prionailurus viverrinus). Estrogen, progestagen and androgen metabolites were quantified in fecal samples collected for 12 months from four males and 10 females housed at seven North American zoological institutions. Male reproductive hormone concentrations did not vary (P>0.05) among season, and estrogen cycles were observed year-round in females and averaged (±SEM) 19.9±1.0 days. Mean peak estrogen concentration during estrus (460.0±72.6ng/g feces) was five-fold higher than baseline (87.3±14.0ng/g feces). Five of seven females (71.4%) housed alone or with another female demonstrated spontaneous luteal activity (apparent ovulation without copulation), with mean progestagen concentration (20.3±4.7μg/g feces), increasing nearly five-fold above baseline (4.1±0.8μg/g feces). The non-pregnant luteal phase averaged 32.9±2.5 days (n=13). One female delivered kittens 70 days after natural mating with fecal progestagen concentrations averaging 51.2±5.2μg/g feces. Two additional females were administered exogenous gonadotropins (150IU eCG; 100IU hCG), which caused hyper-elevated concentrations of fecal estrogen and progestagen (plus ovulation). Results indicate that: (1) male and female fishing cats managed in North American zoos are reproductively active year round; (2) 71.4% of females experienced spontaneous ovulation; and (3) females are responsive to exogenous gonadotropins for ovulation induction, but a regimen that produces a normative ovarian steroidogenic response needs to be identified.  相似文献   

9.
Ammonia emission from animal production is a major environmental problem and has impacts on the animal health and working environment inside production houses. Ammonia is formed in manure by the enzymatic degradation of urinary urea and catalyzed by urease that is present in feces. We have determined and compared the urease activity in feces and manure (a urine and feces mixture) from pigs and cattle at 25°C by using Michaelis-Menten kinetics. To obtain accurate estimates of kinetic parameters Vmax and K''m, we used a 5 min reaction time to determine the initial reaction velocities based on total ammoniacal nitrogen (TAN) concentrations. The resulting Vmax value (mmol urea hydrolyzed per kg wet feces per min) was 2.06±0.08 mmol urea/kg/min and 0.80±0.04 mmol urea/kg/min for pig feces and cattle feces, respectively. The K''m values were 32.59±5.65 mmol urea/l and 15.43±2.94 mmol urea/l for pig feces and cattle feces, respectively. Thus, our results reveal that both the Vmax and K''m values of the urease activity for pig feces are more than 2-fold higher than those for cattle feces. The difference in urea hydrolysis rates between animal species is even more significant in fresh manure. The initial velocities of TAN formation are 1.53 mM/min and 0.33 mM/min for pig and cattle manure, respectively. Furthermore, our investigation shows that the maximum urease activity for pig feces occurs at approximately pH 7, and in cattle feces it is closer to pH 8, indicating that the predominant fecal ureolytic bacteria species differ between animal species. We believe that our study contributes to a better understanding of the urea hydrolysis process in manure and provides a basis for more accurate and animal-specific prediction models for urea hydrolysis rates and ammonia concentration in manures and thus can be used to predict ammonia volatilization rates from animal production.  相似文献   

10.
By means of an aerobic enrichment culture technique, several bacteria that hydrolyze conjugated bile acids and modify the formed deconjugates were isolated from feces of man, rat, and chicken and from soil. Hydrolase activity was intracellular and extractable, and the yield of the enzymes was increased by adding the conjugated bile acids to the culture media. The hydrolase from bacterium of human origin was stable, having a pH optimum at about 7.0. All bile acid conjugates were hydrolyzed linearly as a function of time.  相似文献   

11.
应用real-timePCR法快速定量人类粪便中双歧杆菌的研究   总被引:1,自引:0,他引:1  
目的建立快速、准确从粪便标本中定量双歧杆菌的RT—PCR技术。方法传统培养定量法,普通PCR定量法,real—timePCR比较测量。结果(I)粪便标本前处理采取简单的离心和清洗、稀释步骤能去除粪便标本中的抑制物,实现不提取DNA直接进行PCR、real—time定量粪便中双歧杆菌。(2)本实验建立的PCR方法直接半定量粪便双歧杆菌技术在双歧杆菌值介于10^3~10^7CFU/ml时具有较好的分辨率,粪便标本普通PCR得理论菌数与培养得菌数值之间差异无显著性(P〉0.05);real-timePCR直接定量双歧杆菌技术在双歧杆菌值介于10^1-10^7CFU/ml时具有较好的分辨率,粪便标本RT—PCR得理论菌数与培养得菌数值之间差异无显著性(P〉0.05)。结论利用PCR、real—timePCR直接半定量和定量粪便中的双歧杆菌可行。  相似文献   

12.
The experiment investigated the effects of skin pressure by clothing on whole gut transit time and amount of feces. Comparisons of transit time and amount of feces were taken between 6 young female adults with and without a girdle. The skin pressure applied by a girdle (mean +/- SD) on participant's waist, abdomen and hip region was 16.6 +/- 7.80 mmHg, 17.1 +/- 4.5 mmHg and 12.6 +/- 5.0 mmHg, respectively. The difference of skin pressure with and without a girdle was about 10 mmHg. During each experimental period of 4 days with and without a girdle, the whole gut transit time and amount of feces were measured. The whole gut transit time of each day was determined as the time between the oral intake of each day's markers and their first appearance in the stool. The whole gut transit times of the markers taken on the first day were significantly prolonged (p < 0.05) and those of the markers taken on the second day tended to be prolonged for participant using a girdle (p < 0.1). The whole gut transit time of the markers taken on the third day could not be compared because they were not excreted into the stool. The cumulative increases of feces on the third day and the fourth day were significantly reduced with a girdle (p < 0.05). These results indicate that the skin pressure by clothing has an effect on whole gut transit time and the amount of feces.  相似文献   

13.
Fried meat was included in the diet of Sprague-Dawley rats during one week. Ingested and excreted amounts of mutagenic activity were determined daily by the use of the Ames' Salmonella/mammalian microsome test on extracts of the diet, urine and feces. In addition, the effect of the fried meat on ethoxyresorufin-O-deethylase activity in the small intestine and in the liver was measured. The results were compared to those from a control group of rats receiving boiled instead of fried meat as their source of protein. The diet containing boiled meat was not mutagenic and none of the samples from the control group, neither urine nor feces, contained any mutagenicity. The activity of ethoxyresorufin O-deethylase in the small intestine was increased by fried meat whereas this enzyme activity in the liver was unaffected. O-deethylation of ethoxyresorufin is catalyzed by cytochrome P-450 dependent enzyme(s) and induction of the enzyme activity might indicate an increased metabolic activation of premutagens and precarcinogens in the intestine. It is not yet known whether the mutagens excreted by the animals receiving the fried meat diet represent unmetabolized dietary mutagens or are formed as a result of metabolic activation of compounds in fried food. Dietary fibers i.e. wheat bran, pectin, cellulose or ViSiblin were included in the above-described diets and were shown to lower the mutagenic activity in urine and feces of the rats. Pectin significantly increased the hepatic ethoxyresorufin-O-deethylase and decreased the 16 alpha-hydroxylation of 4-androstene-3,17-dione.  相似文献   

14.
Significance of microflora in proteolysis in the colon.   总被引:5,自引:3,他引:2       下载免费PDF全文
Protease activities in human ileal effluent and feces were compared by using a variety of native and diazotized protein substrates. In many cases the diazotized proteins had altered susceptibilities to hydrolysis compared with the native proteins. Proteolytic activity was significantly greater than (P less than 0.001) in small intestinal effluent than in feces (319 +/- 45 and 11 +/- 6 mg of azocasein hydrolyzed per h per g, respectively). Moreover, fecal proteolysis was qualitatively different in that ileal effluent did not hydrolyze the highly globular protein bovine serum albumin, whereas all fecal samples tested degraded this substrate. Inhibition experiments provided further evidence that fecal protease activity differed from that in the small intestine. Physical disruption of fecal bacteria released large quantities of proteases, indicating that the lysis of bacteria in the colon may contribute to the extracellular proteolytic activity in feces. Protease inhibition studies with washed fecal bacteria showed that they produced serine, cystine, and metalloproteases, and experiments with synthetic p-nitroanilide substrates indicated that low levels of trypsin- and chymotrypsin-like activities were associated with whole cells. An elastase-like enzyme was bound to the outer membranes of some fecal bacteria.  相似文献   

15.
16.
Significance of microflora in proteolysis in the colon   总被引:1,自引:0,他引:1  
Protease activities in human ileal effluent and feces were compared by using a variety of native and diazotized protein substrates. In many cases the diazotized proteins had altered susceptibilities to hydrolysis compared with the native proteins. Proteolytic activity was significantly greater than (P less than 0.001) in small intestinal effluent than in feces (319 +/- 45 and 11 +/- 6 mg of azocasein hydrolyzed per h per g, respectively). Moreover, fecal proteolysis was qualitatively different in that ileal effluent did not hydrolyze the highly globular protein bovine serum albumin, whereas all fecal samples tested degraded this substrate. Inhibition experiments provided further evidence that fecal protease activity differed from that in the small intestine. Physical disruption of fecal bacteria released large quantities of proteases, indicating that the lysis of bacteria in the colon may contribute to the extracellular proteolytic activity in feces. Protease inhibition studies with washed fecal bacteria showed that they produced serine, cystine, and metalloproteases, and experiments with synthetic p-nitroanilide substrates indicated that low levels of trypsin- and chymotrypsin-like activities were associated with whole cells. An elastase-like enzyme was bound to the outer membranes of some fecal bacteria.  相似文献   

17.
The effect of food composition on the digestive system of Penaeus vannamei shrimp was used to determine the suitability of feces for analysis of class, type, composition of digestive proteinases, and whether alterations in the digestive gland are mirrored in feces composition. Enzymes recovered from feces and the midgut gland of white shrimp P. vannamei were used for comparison purposes. Three groups of shrimp were assembled: two groups fed two different brands of commercial feeds (PI and SC) with different content of protein, and the last group fed 50% PI feed and 50% thawed giant squid. Composition of proteinases in the midgut gland and feces were identical, and trypsin and chymotrypsin paralogues were identified in both samples by substrate-electrophoresis. Total proteolytic, trypsin, and chymotrypsin enzyme activities were higher in both samples from organisms fed SC, than in the other two groups. In the hepatopancreas, trypsin activity was ∼30% higher in SC fed group. Final average weights of shrimp were close in three groups, but hepatopancreas weight was 20% higher in the SC group. The degree of protein hydrolysis (DH) in vitro for the SC and PI was evaluated by the pH-stat method, using enzymes from feces and hepatopancreas of each group. The DH of food was no different, but it was affected by enzyme source, hepatopancreas extract (HPE) or feces extract (FE). DH was always higher when FE was the enzyme source than when HPE was the source. The proposed methods for recovery of enzymes from shrimp feces can be applied to other crustaceans. Measurements were sufficiently sensitive to allow quantifying the effects of feed on digestion physiology and other ecological and physiological applications, without the necessity of killing specimens.  相似文献   

18.
鸟类对山黄麻种子的传播及其生态作用   总被引:14,自引:1,他引:13  
在云南西双版纳的勐宋和勐仑地区观察和研究了传统山黄麻种子的鸟类。在野外持网捕获摄食山黄麻果实的鸟类,称量后分别放在布袋内,让其自然排泄,然后标志释放,观察和网捕共记录到摄食山黄麻果实的鸟类36种,其中26种挂网捕获并从排泄物得到种子。用鸟类排泄物中的山黄麻种子、山黄麻树上采摘的成熟果实及人工分离山黄麻种子播种,进行萌发对比实验,实验结果表明,直接播种成熟果实,在阳光充足的空旷地、林冠下或用树叶覆盖遮光等条件下都未萌发,种子容易霉烂或被虫蚀;从山黄麻果肉中分离出来的种子具有萌发能力;而经鸟类摄食、消化后从果肉中分离的种子,具有较好的萌发活力。在不同条件下山黄麻种子萌发情况差异明显,林冠下条件对种子有抑制作用,阳光作用下种子显示出很好的萌发及成活率。鸟类排泄物种子放在林上或用树叶覆盖遮光,经过较长时间便可萌发,而人工分离种子不能萌发。鸟类摄食及消化过程对山黄麻种子的处理表现出很好的生态互惠关系,观察萌发后的山黄麻幼苗的生长情况还表明,幼苗生长也需要光照和较开阔的生境条件,鸟类取食山黄麻果实及其将种子远距离传播适宜生境,正好具有这样的生态作用。  相似文献   

19.
It is important to clarify the distribution of infected triatomine bugs in the endemic area of Chagas' disease for proper control. In the present study, we tried to detect T. cruzi kinetoplast DNA by PCR from dried triatomine feces collected from the house wall of an endemic area to assess the distribution of infected bugs more easily. The primers (P35/P36) were chosen to amplify the conserved region within the minirepeats of T. cruzi kinetoplast minicircle DNA. The kinetoplast DNA of T. cruzi could be actually detected in the dried feces collected from the wall of a brick-built house in Santa Cruz, Bolivia. Next, we examined the stability of T. cruzi kinetoplast DNA in the feces exposed to artificial environments. T. cruzi DNA was also detected by PCR in the feces left for 26 weeks at 25 degrees C and in those left for 4 weeks at 40 degrees C. The present study indicates that examination of dried feces on the wall can be an effective tool for surveillance of the natural infection of triatomine bugs that live in houses.  相似文献   

20.
目的从健康仔猪肠道及粪便中筛选具有胆盐水解酶活性的优良益生乳杆菌菌株,并对筛选菌株的体外、体内益生潜力进行初步探讨。方法用MRS培养基分别从仔猪新鲜粪便和小肠黏膜分离培养乳酸菌,用筛选鉴别培养基筛选阳性菌株,研究菌株的抗逆能力、黏附特性以及体内益生活性。结果从粪便和小肠黏膜共得到乳酸菌388株和97株,其中胆盐水解酶阳性菌株分别为291株(75%)和86株(89%)。选择5株胆盐水解酶活性最强、能水解游离胆酸的菌株,研究菌株的抗逆能力、黏附特性以及体内益生活性,并对最终选育得到的菌株进行生理生化及16S rRNA分子鉴定,发现菌株罗伊乳杆菌G22-2能耐受pH 3.0的酸度、1.0%的胆盐浓度,在小肠上皮细胞上的黏附效率超过15个以上;通过大鼠体内实验,筛选出的菌株G22-2对大鼠无毒无害,并能显著改善血脂水平。结论罗伊乳杆菌G22-2符合益生菌的要求,可以作为产胆盐水解酶的益生乳杆菌优良的候选菌株。  相似文献   

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