BACKGROUND: This study examined the changes in soil fertility in a maize cropping area when chemical fertilizer was partially replaced with straw or livestock manure over a 33-year period. Four treatments were included: (i) CK (no fertilizer application); (ii) NPK (only chemical fertilizer application); (iii) NPKM (chemical fertilizer partly replaced with livestock manure); (iv) NPKS (chemical fertilizer partly replaced with straw).
RESULTS: Soil organic carbon increased by 41.7% and 95.5% in the NPKS and NPKM treatments, respectively, over the 33-year trial compared with the initial concentration. However, soil organic carbon in NPK was significantly reduced by 9.8%. Soil total N, P and K increased in both NPKM and NPKS treatments compared to the original soil. Soil pH was significantly acidified from 7.6 to 5.97 in the NPK treatment during the experimental period. The NPKM and NPKS treatments buffered the acidification compared to NPK. Meta-analysis results showed that, compared with NPK, NPKM significantly raised soil bacteria and fungi populations by 38.7% and 58.6%; enhanced microbial biomass carbon and nitrogen by 66.3% and 63%, respectively; and increased sucrase, urease and catalase activities by 34.2%, 48.2% and 21.5%. NPKS significantly increased soil fungi and actinomycetes populations by 24.3% and 41.2%, respectively; enhanced microbial biomass carbon and nitrogen by 27.1% and 45%; and strengthened sucrase and urease activities by 36% and 20.3%, respectively.
CONCLUSIONS: Long-term chemical fertilizer application led to the deterioration of soil fertility and environment. Partial replacement of chemical fertilizers with organic materials could significantly amend and buffer such negative effects. © 2023 Society of Chemical Industry.

OBJECTIVE: To evaluate the effectiveness of enteroprotector Rebamipide in the treatment of enteropathy with impaired membrane digestion (EIMD).
METHODS: We examined 102 patients aged 18 to 50 years (41 men and 61 women) with clinical signs of irritable bowel syndrome (n=65), functional diarrhea (n=33), and functional constipation (n=4) according to Rome IV criteria (2016). The activities of glucoamylase (GA), maltase, sucrase and lactase were determined by Dahlquist-Trinder method in duodenal biopsies obtained during esophagogastroduodenoscopy. The control group consisted of 20 healthy people aged 23-47. They showed following average enzyme activity: lactase - 42±13 ng glucose on 1 mg of tissue per minute, GA - 509±176, maltase - 1735±446, sucrase - 136±35 ng glucose on 1 mg of tissue per minute. These numbers were taken as the norm.
RESULTS: The activity of the disaccharidases was reduced in 89.2% out of 102 patients, and they were diagnosed with EIMD. Thirteen patients with EIMD were recommended to maintain the FODMAP diet and take enteroprotector Rebamipide 100 mg 3 times a day for 12 weeks. After 3 months 11 patients reported decreased or no flatulence, abdominal pain, stool disorder; 2 patients reported no change. The activity of GA increased to an average of 149±82 (by 78%, p=0.016), maltase - to 864±472 (by 131%, p=0.0019), sucrase - 63±35 (by 95%, p=0.0041) and lactase - 10±8 ng glucose on 1 mg of tissue per minute. The activity of lactase did not change.
CONCLUSIONS: We discovered a previously unknown phenomenon of the disaccharidases activity increase in duodenal mucosa and improved carbohydrates tolerance in the patients with EIMD taking Rebamipide in the dose 300 mg/day for 12 weeks.

α-glucosidase inhibitors (AGIs) have been an important category of oral antidiabetic drugs being widely exploited for the effective management of type 2 diabetes mellitus. However, the marketed AGIs not only inhibited the disaccharidases, but also exhibited an excessive inhibitory effect on α-amylase, resulting in undesirable gastrointestinal side effects. Compared to these agents, Ramulus Mori alkaloids (SZ-A), was a group of effective alkaloids from natural Morus alba L., and showed excellent hypoglycemic effect and fewer side effects in the Phase II/III clinical trials. Thus, this paper aims to investigate the selective inhibitory effect and mechanism of SZ-A and its major active ingredients (1-DNJ, FA and DAB) on different α-glucosidases (α-amylase and disaccharidases) by using a combination of kinetic analysis and molecular docking approaches. From the results, SZ-A displayed a strong inhibitory effect on maltase and sucrase with an IC50 of 0.06 μg/mL and 0.03 μg/mL, respectively, which was similar to the positive control of acarbose with an IC50 of 0.07 μg/mL and 0.68 μg/mL. With regard to α-amylase, SZ-A exhibited no inhibitory activity at 100 μg/mL, while acarbose showed an obvious inhibitory effect with an IC50 of 1.74 μg/mL. The above analysis demonstrated that SZ-A could selectively inhibit disaccharidase to reduce hyperglycemia with a reversible competitive inhibition, which was primarily attributed to the three major active ingredients of SZ-A, especially 1-DNJ molecule. In the light of these findings, molecular docking study was utilized to analyze their inhibition mechanisms at molecular level. It pointed out that acarbose with a four-ring structure could perform desirable interactions with various α-glucosidases, while the three active ingredients of SZ-A, belonging to monocyclic compounds, had a high affinity to the active site of disaccharidases through forming a wide range of hydrogen bonds, whose affinity and consensus score with α-amylase was significantly lower than that of acarbose. Our study illustrates the selective inhibition mechanism of SZ-A on α-glucosidase for the first time, which is of great importance for the treatment of type 2 diabetes mellitus.

Although polyphenols inhibit glucose absorption and transport in vitro, it is uncertain whether this activity is sufficient to attenuate glycaemic response in vivo. We examined this using orange juice, which contains high levels of hesperidin. We first used a combination of in vitro assays to evaluate the potential effect of hesperidin and other orange juice components on intestinal sugar absorption and then tested whether this translated to an effect in healthy volunteers. Hesperidin attenuated transfer of 14C-labelled glucose across differentiated Caco-2/TC7 cell monolayers. The involvement of the sugar transporter GLUT2 was demonstrated by experiments carried out in the absence of Na to exclude the contribution of sodium-glucose linked transporter 1 and further explored by the use of Xenopus laevis oocytes expressing human GLUT2 or GLUT5. Fructose transport was also affected by hesperidin partly by inhibition of GLUT5, while hesperidin, even at high concentration, did not inhibit rat intestinal sucrase activity. We conducted three separate crossover interventions, each on ten healthy volunteers using orange juice with different amounts of added hesperidin and water. The biggest difference in postprandial blood glucose between orange juice and control, containing equivalent amounts of glucose, fructose, sucrose, citric acid and ascorbate, was when the juice was diluted (ΔC max=-0·5 mm, P=0·0146). The effect was less pronounced when the juice was given at regular strength. Our data indicate that hesperidin can modulate postprandial glycaemic response of orange juice by partial inhibition of intestinal GLUT, but this depends on sugar and hesperidin concentrations.

Glucansucrases (GSs) in glycoside hydrolase family 70 (GH70) catalyze the synthesis of α-glucans from sucrose, a reaction that is widely seen in lactic acid bacteria (LAB). These enzymes have been implicated in many aspects of microbial life. Products of GSs have great commercial value as food supplements and medical materials; therefore, these enzymes have attracted much attention from both science and industry. Certain issues concerning the origin and evolution of GSs are still to be addressed, although an increasing number of GH70 enzymes have been characterized. This study describes a GS enzyme with the appearance of a branching sucrase (BrS). Structural analysis indicated that this GS enzyme produced a type of glucan composed of an α-(1→6) glucosidic backbone and α-(1→4) branches, as well as a considerable amount of α-(1→3) branches, distinguishing it from the GSs identified so far. Moreover, sequence-based analysis of the catalytic core of this enzyme suggested that it might be an evolutionary intermediate between the BrS and GS subgroups. These results provide an evolutionary link between these subgroups of GH70 enzymes and shed new light on the origination of GSs.IMPORTANCE GH70 GSs catalyze the synthesis of α-glucans from sucrose, a reaction that is widely seen in LAB. Products of these enzymes have great commercial value as food supplements and medical materials. Moreover, these enzymes have attracted much attention from scientists because they have potential in tailored synthesis of α-glucans with desired structures and properties. Although more and more GSs have been characterized, the origin and evolution of these enzymes have not been well addressed. This study describes a GS with the appearance of a BrS (i.e., high levels of similarity to BrSs in sequence analysis). Further analysis indicated that this enzyme synthesized a type of insoluble glucan composed of an α-(1→6) glucosidic backbone and many α-(1→4)- and α-(1→3)-linked branches, the linkage composition of which has rarely been reported in the literature. This BrS-like GS enzyme might be an evolutionary intermediate between BrS and GS enzymes.

In patients with the Congenital Sucrase-Isomaltase Deficiency (CSID), who lack intestinal sucrase-isomaltase enzyme, a suspension of yeast sucrase is applied as a drug to compensate the enzyme deficiency. While antipsychotic drugs are used for the treatment of schizophrenia, administering multiple drugs at the same time may counteract each other.
In this study, the interaction between trifluoperazine and haloperidol as antipsychotic drugs on oral drug yeast sucrase was investigated. In this regard, the kinetic parameters of enzyme were determined in the presence or absence of the drugs. The kinetic parameters of the drugs such as Ki and IC50 were also calculated. Lineweaver - Burk plot was used to reveal the type of inhibition.
The results showed that both drugs could reduce sucrase activity and decrease the Vmax of the enzyme by non-competitive inhibition. The IC50 and Ki values of the drugs were determined to be 0.7 and 0.068 mM and 0.45 and 0.063 mM for haloperidol and trifluoperazine, respectively. The results suggested that trifluoperazine binds to the enzyme with higher affinity than haloperidol. Fluorescence measurement was used for conformational investigations of the drugs and sucrase interaction. It was shown that the drugs bind to free enzyme and enzyme-substrate complex which are accompanied with hyperchromicity. This suggests that tryptophan residues of the enzyme transferred to hydrophobic medium after binding of the drugs to the enzyme.
The finding of this research revealed that both trifluoperazine and haloperidol could inhibit sucrase in non-competitive manner. The kinetic parameters and conformational changes due to binding of trifluoperazine to the enzyme were different from that of haloperidol.

The aim of this study was to determine the possible underlying mechanism of the hypoglycaemic activity of the ethanolic extract of Nauclea latifolia leaves in rats. The extract, glibenclamide or water was administered orally in a glucose, sucrose and maltose tolerance tests. In addition, the effect of the extract on α-glucosidase enzymes was also studied. The ethanolic extract at 200mg/kg body weight inhibited the increase in glucose level after both oral and intraperitoneal glucose loads as did glibenclamide. The extract also dose dependently inhibited both maltase and sucrase activities in vitro but not in vivo. The hypoglycaemic effect of N. latifolia leaf ethanolic extract thus appears to be most probably exerted through a mechanism similar to that of glibenclamide which is related to increased insulin release from pancreatic β-cells.

The synthesis, conformational study and inhibitory properties of diverse indolizidine and quinolizidine iminocyclitols are described. The compounds were chemo-enzymatically synthesized by two-step aldol addition and reductive amination reactions. The aldol addition of dihydroxyacetone phosphate (DHAP) to N-Cbz-piperidine carbaldehyde derivatives catalyzed by L-rhamnulose 1-phosphate aldolase from Escherichia coli provides the key intermediates. The stereochemical outcome of both aldol addition and reductive amination depended upon the structure of the starting material and intermediates. The combination of both reactions furnished five indolizidine and six quinolizidine type iminocyclitols. A structural analysis by NMR and in silico density functional theory (DFT) calculations allowed us to determine the population of stereoisomers with the trans or cis ring fusion, as a consequence of the inversion of configuration of the bridgehead nitrogen. The trans fusion was by far the most stable, but for certain stereochemical configurations of the 3-hydroxymethyl and hydroxyl substituents both trans and cis fusion stereoisomers coexisted in different proportions. Some of the polyhydroxylated indolizidines and quinolizidines were shown to be moderate to good inhibitors against α-L-rhamnosidase from Penicillium decumbens. Indolizidines were found to be moderate inhibitors of the rat intestinal sucrase and of the exoglucosidase amyloglucosidase from Aspergillus niger. In spite of their activity against α-L-rhamnosidase, all the compounds were ineffective to inhibit the growth of the Mycobacterium tuberculosis, the causative agent of tuberculosis.

The present study investigated the in vitro hypoglycemic activity of basil (Ocimum basilicum) aqueous extract. Preliminary phytochemical screening of the extract revealed the presence of reducing sugars, cardiac glycosides, tannins, saponins, glycosides, flavonoids and steroids. The total polyphenols content (TPC), flavonoids content (FC), percentage diphenylpicrylhydrazyl (DPPH( · )) radical inhibition and total antioxidant status (TAS) were estimated. The FC was 41 ± 2.2 rutin/g dry extract, the TPC was 146 ± 5.26 mg catechin/g dry extract and the TAS was 5.12 ± 0.7 mmol/L. The %DPPH( · ) free radical inhibition was 60%, 54%, 49% and 43%, respectively, for different extract concentrations; 20, 18.2, 16.3 and 14.5 mg/ml, respectively. The extract elicited significant dose-dependent pattern against rat intestinal sucrase (RIS; IC(50) = 36.72 mg/ml), rat intestinal maltase (RIM; IC(50) = 21.31 mg/ml) and porcine pancreatic α-amylase (PPA; IC(50) = 42.50 mg/ml) inhibitory activities. The inhibition was greater against maltase compared with sucrase. These effects may be attributed to the high TPC and FC levels. The linear regression analysis revealed strong significant positive correlations between %DPPH( · ) radical inhibition and each of %RIS, %RIM and %PPA inhibiting activity. Also, strong significant positive correlations between %RIS and either %RIM or %PPA inhibition activity were observed. We concluded therefore that basil aqueous extract via antioxidant and possibly α-glucosidase and α-amylase inhibiting activities, offered positive benefits to control diabetes.

Herbal medicines have been used since prehistoric times by different cultures worldwide for the treatment of diabetes. The present investigation evaluated the effect of Ficus racemosa Linn. (Moraceae) stem bark on carbohydrate hydrolyzing enzymes, viz., porcine pancreatic alpha-amylase, rat intestinal alpha-glucosidase, sucrase, and almond beta-glucosidase, using in vitro model systems. In addition, the effect of heat treatment was also studied. Untreated F. racemosa bark (FRB) significantly inhibited (p < or = 0.05) alpha-amylase, alpha-glucosidase, beta-glucosidase, and sucrase in a dose-dependent manner. Heat treatment of the sample comparably increased alpha-amylase, alpha-glucosidase, and sucrase inhibitory activities, while a marginal decrease in beta-glucosidase inhibitory activity was observed; however, no statistical differences were noted. Untreated FRB showed IC(50) values of 0.94% and 280, 212, and 367 microg/mL for alpha-amylase, alpha-glucosidase, beta-glucosidase, and sucrase, respectively, while the IC(50) values for heat treated FRB were 0.58% and 259, 223, and 239 microg/mL, respectively. Further, a significant correlation (p < or = 0.01; r = 0.791) was observed between alpha-amylase, alpha-glucosidase, beta-glucosidase, and sucrase inhibitory activities of both untreated and heat treated FRB. The results clearly demonstrate that inhibition of carbohydrate hydrolyzing enzymes is one mechanism through which F. racemosa stem bark exerts its hypoglycemic effect in vivo. Therefore, the potential exists to explore the utilization of F. racemosa stem bark in the development of nutraceuticals and functional foods for the management of diabetes and related symptoms/disorders.