As an important medicinal intermediate with broad uses, validamine, an aminocyclitol, isolated from the enzymolysis broth of validamycins, has gained more and more attention. The absolute configuration of validamine i...As an important medicinal intermediate with broad uses, validamine, an aminocyclitol, isolated from the enzymolysis broth of validamycins, has gained more and more attention. The absolute configuration of validamine is similar to that of a-D-glucose, and it demonstrates powerful inhibition activity on glycosidase. In this paper, the inhibitory effect of validamine on porcine small intestinal sucrase was investigated. Validamine was found to be a potent, competitive inhibitor to porcine small intestinal sucrase in vitro with an IC50 value of 6.85 X 10(-4) mol center dot L-1. Validamine exhibited a dose-dependent inhibition effect on porcine small intestinal sucrase, whereby the inhibition interaction of validamine and porcine small intestinal sucrase was a fast binding process. The inhibition of validamine on porcine small intestinal sucrase was pH-dependent.展开更多
The authors presented the enzyme characteristics of catalase, sucrase, urease and alkaline phosphatase under agroforestry systems in northern Jiangsu Province. The results show that soil enzyme activities reduce gradu...The authors presented the enzyme characteristics of catalase, sucrase, urease and alkaline phosphatase under agroforestry systems in northern Jiangsu Province. The results show that soil enzyme activities reduce gradually from top to bottom layer of the soil profile, and the fluctuations of catalase and urease are smaller than those of sucrase and alkaline phosphatase. Soil enzyme activities differe significantly in different samples, and the order is arranged as poplar-crop intercropping segment (A, D) > paulownia-crop intercropping segment (B, C) > CK. Furthermore, soil enzyme activities increase with intercropping age. On the other hand, in the same plot, there are closer relationships between enzymes in the soil samples. Catalase, alkaline phosphatase and urease are negatively related, while alkaline phosphatase and urease are positively related (except in samples B and C). In addition, the enzyme activities have a close relationship with the fertilizers. Catalase is positively correlated with the soil pH value (r = 0.854, 0.804, 0.078 and 0.082, respectively), and is negatively correlated with total N (r = –0.201, –0.529, –0.221 and –0.821, respectively), total P (r = –0.143, –0.213, –0.362 and –0.751, respectively) and available P (r = –0.339, –0.351, –0.576, and –0.676, respectively). Sucrase, urease and alkaline phosphatase are negatively correlated with the pH value, while positively correlated with the other fertilizers (r 1). The authors suggest that enzyme activity will be a great potential as an indicator of soil quality.展开更多
AIM: To examine the effect of increasing dietary zinc (Zn) intake and the lack of metallothionein (MT) expression on activity of small intestinal disaccharidases. METHODS: MT-Ⅰ and Ⅱ knockout (MT-/-) and wild-type (...AIM: To examine the effect of increasing dietary zinc (Zn) intake and the lack of metallothionein (MT) expression on activity of small intestinal disaccharidases. METHODS: MT-Ⅰ and Ⅱ knockout (MT-/-) and wild-type (MT+/+) female mice at 3.5 wk of age were randomly fed with a diet containing 2 (2 Zn), 15 (15 Zn) or 50 (50 Zn) mg Zn/kg (n = 8/group/genotype) for 5 wk. Small intestinal segments (duodenum, jejunum and ileum) were collected and either fixed in 10% formalin for histological analysis or snap frozen in liquid nitrogen for sucrase, lactase and maltase activity analyses.RESULTS: Plasma Zn was significantly (P < 0.05) lower (33%) in MT-/- compared with MT+/+ mice fed the 2 Zn diet. Villus height and crypt depth were increased by approximately 15% in MT+/+ mice compared with MT-/- mice. Duodenal disaccharidase activities were significantly higher in MT+/+ compared with MT-/- mice particularly in those fed the 2 Zn diet. For the 50 Zn diet, jejunal sucrase and lactase activities were significantly higher in MT-/- (13 313 ± 2314; 4107 ± 364 μmol glucose/well/min/g tissue, respectively) compared with MT+/+ mice (7054 ± 608; 1818 ± 174). Similarly, ileal lactase activities were higher in MT-/- (1480 ± 192) compared with MT+/+ (629 ± 353) mice particularly those fed the 2 Zn diet. CONCLUSION: Increasing dietary Zn has little effect on disaccharidases activity in MT wild-type mice. The presence of MT may enhance morphological and functional development of the gut.展开更多
BACKGROUND Functional bowel disorder(FBD)may be caused by a decrease in disaccharidase activity.Thus,the timely diagnosis of disaccharidase deficiency could lead to a better prognosis in patients with this condition.A...BACKGROUND Functional bowel disorder(FBD)may be caused by a decrease in disaccharidase activity.Thus,the timely diagnosis of disaccharidase deficiency could lead to a better prognosis in patients with this condition.AIM To determine the potential value of intestinal disaccharidases glucoamylase,maltase,sucrase,and lactase in understanding the etiology and pathogenesis of FBD.METHODS A total of 82 FBD patients were examined.According to the Rome IV criteria(2016),23 patients had diarrhea-predominant irritable bowel syndrome(IBS),33 had functional diarrhea,10 had constipation-predominant IBS,4 had functional constipation,and 12 had mixed IBS.The Dahlqvist method was used to measure disaccharidase activity in the brush-border membrane of mature enterocytes of the small intestine,in duodenal biopsies obtained during esophagogastroduodenoscopy.RESULTS Lactase deficiency was detected in 86.5%of patients,maltase deficiency in 48.7%,sucrase deficiency in 50%,and glucoamylase deficiency in 84.1%.The activities of all enzymes were reduced in 31.7%of patients,and carbohydrase deficiency was detected in 63.5%of patients.The low activity of enzymes involved in membrane digestion in the small intestine was found in 95.2%of patients.CONCLUSION In 78 of the 82 patients with FBD,gastrointestinal symptoms were associated with disaccharidase deficiency.展开更多
[Objectives]The purpose of this study was to investigate the effects of Pb on rhizosphere soil enzyme activity and chemical constituents of Achyranthes bidentata Blume.[Methods]A.bidentata Blume plants were cultivated...[Objectives]The purpose of this study was to investigate the effects of Pb on rhizosphere soil enzyme activity and chemical constituents of Achyranthes bidentata Blume.[Methods]A.bidentata Blume plants were cultivated in self-made polyvinyl chloride(PVC)pots.The soil was added with different levels of Pb(0,200,400,600,800 and 1000 mg/kg air-dried soil)to investigate the effects of Pb on dry mass,active ingredients(oleanolic acid and ecdysterone)and rhizosphere soil enzyme activity of A.bidentata Blume.[Results]The root dry mass of A.bidentata Blume cultivated in the soil with Pb level above 400 mg/kg significantly reduced.The Pb residues in the A.bidentata Blume.plants growing in the soil with Pb level below 400 mg/kg complied with national standard.The contents of oleanolic acid and ecdysterone in A.bidentata Blume growing in the soil with Pb level above 600 mg/kg declined significantly.At the Pb level of 1000 mg/kg,the activity of urease was inhibited significantly.The activity of phosphatase was inhibited in the presence of Pb in the soil.The activity of sucrase was activated in the soil with Pb level below 400 mg/kg,and was inhibited in the soil with Pb level above 400 mg/kg.[Conclusions]This study has important guiding significance for the reasonable selection of planting base for A.bidentata Blume and the guarantee of its yield and quality.展开更多
基金Supported by the National Fund of the Major Basic Research Development Program (973 Project) (No.2003CB716005)the National Natural Science Foundation of China (No. 20176055) the Natural Science Foundation of Zhejiang Province (No. ZB0106).
文摘As an important medicinal intermediate with broad uses, validamine, an aminocyclitol, isolated from the enzymolysis broth of validamycins, has gained more and more attention. The absolute configuration of validamine is similar to that of a-D-glucose, and it demonstrates powerful inhibition activity on glycosidase. In this paper, the inhibitory effect of validamine on porcine small intestinal sucrase was investigated. Validamine was found to be a potent, competitive inhibitor to porcine small intestinal sucrase in vitro with an IC50 value of 6.85 X 10(-4) mol center dot L-1. Validamine exhibited a dose-dependent inhibition effect on porcine small intestinal sucrase, whereby the inhibition interaction of validamine and porcine small intestinal sucrase was a fast binding process. The inhibition of validamine on porcine small intestinal sucrase was pH-dependent.
文摘The authors presented the enzyme characteristics of catalase, sucrase, urease and alkaline phosphatase under agroforestry systems in northern Jiangsu Province. The results show that soil enzyme activities reduce gradually from top to bottom layer of the soil profile, and the fluctuations of catalase and urease are smaller than those of sucrase and alkaline phosphatase. Soil enzyme activities differe significantly in different samples, and the order is arranged as poplar-crop intercropping segment (A, D) > paulownia-crop intercropping segment (B, C) > CK. Furthermore, soil enzyme activities increase with intercropping age. On the other hand, in the same plot, there are closer relationships between enzymes in the soil samples. Catalase, alkaline phosphatase and urease are negatively related, while alkaline phosphatase and urease are positively related (except in samples B and C). In addition, the enzyme activities have a close relationship with the fertilizers. Catalase is positively correlated with the soil pH value (r = 0.854, 0.804, 0.078 and 0.082, respectively), and is negatively correlated with total N (r = –0.201, –0.529, –0.221 and –0.821, respectively), total P (r = –0.143, –0.213, –0.362 and –0.751, respectively) and available P (r = –0.339, –0.351, –0.576, and –0.676, respectively). Sucrase, urease and alkaline phosphatase are negatively correlated with the pH value, while positively correlated with the other fertilizers (r 1). The authors suggest that enzyme activity will be a great potential as an indicator of soil quality.
基金Supported by (in part) the MS McLeod Post-Doctoral Fellowship obtained from the Women’s and Children’s Hospital Foundation (to Tran CD)
文摘AIM: To examine the effect of increasing dietary zinc (Zn) intake and the lack of metallothionein (MT) expression on activity of small intestinal disaccharidases. METHODS: MT-Ⅰ and Ⅱ knockout (MT-/-) and wild-type (MT+/+) female mice at 3.5 wk of age were randomly fed with a diet containing 2 (2 Zn), 15 (15 Zn) or 50 (50 Zn) mg Zn/kg (n = 8/group/genotype) for 5 wk. Small intestinal segments (duodenum, jejunum and ileum) were collected and either fixed in 10% formalin for histological analysis or snap frozen in liquid nitrogen for sucrase, lactase and maltase activity analyses.RESULTS: Plasma Zn was significantly (P < 0.05) lower (33%) in MT-/- compared with MT+/+ mice fed the 2 Zn diet. Villus height and crypt depth were increased by approximately 15% in MT+/+ mice compared with MT-/- mice. Duodenal disaccharidase activities were significantly higher in MT+/+ compared with MT-/- mice particularly in those fed the 2 Zn diet. For the 50 Zn diet, jejunal sucrase and lactase activities were significantly higher in MT-/- (13 313 ± 2314; 4107 ± 364 μmol glucose/well/min/g tissue, respectively) compared with MT+/+ mice (7054 ± 608; 1818 ± 174). Similarly, ileal lactase activities were higher in MT-/- (1480 ± 192) compared with MT+/+ (629 ± 353) mice particularly those fed the 2 Zn diet. CONCLUSION: Increasing dietary Zn has little effect on disaccharidases activity in MT wild-type mice. The presence of MT may enhance morphological and functional development of the gut.
文摘BACKGROUND Functional bowel disorder(FBD)may be caused by a decrease in disaccharidase activity.Thus,the timely diagnosis of disaccharidase deficiency could lead to a better prognosis in patients with this condition.AIM To determine the potential value of intestinal disaccharidases glucoamylase,maltase,sucrase,and lactase in understanding the etiology and pathogenesis of FBD.METHODS A total of 82 FBD patients were examined.According to the Rome IV criteria(2016),23 patients had diarrhea-predominant irritable bowel syndrome(IBS),33 had functional diarrhea,10 had constipation-predominant IBS,4 had functional constipation,and 12 had mixed IBS.The Dahlqvist method was used to measure disaccharidase activity in the brush-border membrane of mature enterocytes of the small intestine,in duodenal biopsies obtained during esophagogastroduodenoscopy.RESULTS Lactase deficiency was detected in 86.5%of patients,maltase deficiency in 48.7%,sucrase deficiency in 50%,and glucoamylase deficiency in 84.1%.The activities of all enzymes were reduced in 31.7%of patients,and carbohydrase deficiency was detected in 63.5%of patients.The low activity of enzymes involved in membrane digestion in the small intestine was found in 95.2%of patients.CONCLUSION In 78 of the 82 patients with FBD,gastrointestinal symptoms were associated with disaccharidase deficiency.
基金Supported by Project of the Education Department of Henan Province(19B360002)Key Discipline Construction Project of Henan University of Animal Husbandry and Economy for Pharmacognosy of Veterinary Herbal Medicine(41000003).
文摘[Objectives]The purpose of this study was to investigate the effects of Pb on rhizosphere soil enzyme activity and chemical constituents of Achyranthes bidentata Blume.[Methods]A.bidentata Blume plants were cultivated in self-made polyvinyl chloride(PVC)pots.The soil was added with different levels of Pb(0,200,400,600,800 and 1000 mg/kg air-dried soil)to investigate the effects of Pb on dry mass,active ingredients(oleanolic acid and ecdysterone)and rhizosphere soil enzyme activity of A.bidentata Blume.[Results]The root dry mass of A.bidentata Blume cultivated in the soil with Pb level above 400 mg/kg significantly reduced.The Pb residues in the A.bidentata Blume.plants growing in the soil with Pb level below 400 mg/kg complied with national standard.The contents of oleanolic acid and ecdysterone in A.bidentata Blume growing in the soil with Pb level above 600 mg/kg declined significantly.At the Pb level of 1000 mg/kg,the activity of urease was inhibited significantly.The activity of phosphatase was inhibited in the presence of Pb in the soil.The activity of sucrase was activated in the soil with Pb level below 400 mg/kg,and was inhibited in the soil with Pb level above 400 mg/kg.[Conclusions]This study has important guiding significance for the reasonable selection of planting base for A.bidentata Blume and the guarantee of its yield and quality.