Α-amylase Inhibitory Activity Research Articles

Antioxidative and Antidiabetic Properties of Skunk Vine (Paederia Foetida L.)

This experiment was executed at the research field of Department of Crop Botany, Bangabandhu Sheikh Mujibur Rahman Agricultural University, Bangladesh during 2019 to 2020. In this study, methanolic extract of different plant parts was used for observing the antioxidant properties such as total phenolic, flavonoids, carotenoids and anthocyanins content in Skunk vine (P. foetida). Results showed that, the total phenolic were more or less similar in leaf (357.62 μg/g) and stem (349.42 μg/g) and that were significantly higher than that of root extract (233.56 μg/g). The highest amount of flavonoid content (602.71 μg/g) was recorded in leaf extract and the content was more or less similar in stem (493.16 μg/g) and root extracts (501.86 μg/g). Maximum amount of anthocyanin content was recorded in leaf (42.04 μg/g) that was identical with that of stem extract (39.68 μg/g) and statistically the lowest amount in root extract (27.44 μg/g). The fresh leaf extracts contained higher carotenoid content (41.96 mg/g) than stem (25.58 mg/g). Total antioxidant activity in respect to percentage of DPPH ((2,2-diphenyl-1-picrylhydrazyl) scavenging efficiency, leaf extract showed 63.78% inhibition efficiency which were significantly higher than that of stem (45.75%) and root (24.19%). α- glucosidase activity was greatly inhibited (59.13%) by leaf extract at the concentration level of 1.5 mg/mL which was better than that of stem (45.60%). Inhibition of α-amylase activity was recorded up to 46.23 and 42.57% by leaf and stem extracts, respectively which were statistically similar. The present study suggests that medicinal plant Skunk vine (P. foetida) has both antioxidative and antidiabetic properties which would be the good source for producing safe natural drugs.
 Bangladesh J. Agril. Res. 46(1): 1-12, March 2021

Salutary Attributes of Probiotic Human Gut Lactobacilli for gut health.

Lactobacilli are GRAS organisms and are important members of gut microbiota. They have been strongly recommended as probiotics because of many benefits provided by them to overall human health. Human gut lactobacilli with salutary properties can provide additional advantages. Limosilactobacillus fermentumL1 MW600457, Limosilactobacillus fermentumL3 MW600480, Limosilactobacillus fermentumL4 MW600464, Limosilactobacillus fermentumL5 MW600493, Limosilactobacillus fermentumL6 MW600495, Limosilactobacillus fermentumL7 MW600496, Limosilactobacillus fermentumL8 MW485761, Lactiplantibacillus plantarumL9 MW485746 and Ligilactobacillus salivariusL10 MW600498 with in vitro probiotic properties were explored for salutogenic characteristics. Salutary properties like β-galactosidase activity, anthelminthic property assay, anti-inflammatory assay, anti-diabetic study, cholesterol assimilation assay and biofilm assay were performed. All the isolates were positive for β-galactosidase activity. The anthelminthic property with minimum paralysis time and death time between 16-25min was shown by Limosilactobacillus fermentumL8 MW485761. Anti-inflammatory activity with bovine serum albumin was maximum at 200μg ml-1 concentration. α-amylase inhibitory activity was maximum for Limosilactobacillus fermentumL8 MW485761 (51%). Maximum cholesterol assimilation was reported for Limosilactobacillus fermentumL6 MW600495 (76%). Strong biofilm forming ability for all isolates improved the colonization and stability as probiotics. Human gut lactobacilli with salutary properties can make an efficient probiotic.

Phytochemical analysis and biological activities of Artemisia vulgaris grown in different altitudes of Nepal

ABSTRACT Herbal medication developed from natural products has antibacterial, antioxidant, and antidiabetic effects on human health. This research aimed at the investigation of the biological activities, estimation of total phenolic and flavonoid content, and Gas Chromatography and Mass Spectrometry (GC-MS) profiling of chemical compounds in Artemisia vulgaris root and leaf grown at three different altitudes of Nepal. The radical scavenging property of the extracts was studied by 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay, antidiabetic activity was performed by α-amylase inhibition activity, and the total phenolic and flavonoid content was estimated by Folin–Ciocalteu phenol reagent and aluminium chloride colorimetric methods. The IC50 against the DPPH activity shown by the root extract of A. vulgaris grown in Kathmandu was evaluated to be 67.31 ± 2.80 µg/mL, whereas the lowest activity was shown by the leaf extract of A. vulgaris grown in Chitwan of IC50 149.62 ± 2.40 µg/mL. The α-amylase enzyme inhibition activity shown by the root extract grown in Gorkha was found to be 39.43% as compared to the leaf extract grown in Gorkha of 8.69%. The total phenolic content was found to be maximum in root grown in Kathmandu of 96.30 ± 0.52 mg.GAE/g, whereas the least was found in leaf grown in Chitwan of 26.04 ± 1.66 mg.GAE/g. The flavonoid content was found to be maximum in leaf extracts of A. vulgaris grown in Kathmandu of 71.15 ± 2.07 mg.QE/g, whereas the least was found in leaf grown in Gorkha of 31.54 ± 0.70 mg.QE/g. The essential oils extracted from the A. vulgaris growing in Gorkha (862 m altitude) showed the effective antibacterial property against Klebsiella pneumonia and Acinetobacter baumannii with zone of inhibition (ZOI) 12 and 15 mm, respectively. Similarly, the essential oils of A. vulgaris growing in Chitwan (208 m altitude) showed the ZOI 12 and 11 mm against Klebsiella pneumonia and Acinetobacter baumannii, respectively. The positive control used was ampicillin and polymyxin with ZOI of 22 mm. However, the extracts from plants growing in all these altitudes are found to be inactive against these organisms. From the results of this study, it can be concluded that the biological activities of leaf and root extracts of A. vulgaris increased with an increase in altitudes, and the plants grown in high altitudes are the rich sources of secondary metabolites that play a significant role against infectious diseases and diabetes in human beings.

Extraction, characterization, antioxidant and α-amylase inhibitory activities of (1 → 3)(1 → 6)-β-D-glucogalactan from Aspergillus niger ATCC 1004.

The optimization of extraction, chemical characterization, and the evaluation of antioxidant activity and α-amylase inhibition capacities of the cell wall polysaccharides extracted from Aspergillus niger ATCC 1004 were studied in this paper. The response surface methodology through a factorial design of three levels indicated the optimal conditions for extraction: pH 13 and 180min. Characterization results showed that the polysaccharide is glucogalactan, consisting of β-D-galactose-linked units (1 → 6) and β-D-linked glucose (1 → 3). The antioxidant activity was evaluated through three in vitro assays. It could effectively scavenge DPPH, ABTS and hydroxyl radicals with inhibition rates of 82.12%, 75.87% and 79.24, respectively, at 6.4mg/mL, which were higher than those of the other polysaccharides. For inhibitory activity against α-amylase, a blocking effect of 53.7% was observed at a concentration of 2mg/mL. Therefore, the cell wall polysaccharides of Aspergillus niger, (1 → 3)(1 → 6)-β-D-glucogalactan, seem to be a promising source for use as an antioxidant, in addition to holding an in vitro hypoglycemic potential.

Evaluation of Antidiabetic, Antioxidant and Anti-Hyperlipidemic Effects of Solanum indicum Fruit Extract in Streptozotocin-Induced Diabetic Rats.

Globally, diabetes mellitus is the most common cause of premature mortality after cardiovascular diseases and tobacco chewing. It is a heterogeneous metabolic disorder characterised by the faulty metabolism of carbohydrates, fats and proteins as a result of defects in insulin secretion or resistance. It was estimated that approximately 463 million of the adult population are suffering from diabetes mellitus, which may grow up to 700 million by 2045. Solanum indicum is distributed all over India and all of the tropical and subtropical regions of the world. The different parts of the plant such as the roots, leaves and fruits were used traditionally in the treatment of cough, asthma and rhinitis. However, the hypoglycaemic activity of the plant is not scientifically validated. The present study aimed to evaluate the antioxidant, antidiabetic and anti-hyperlipidaemic activity of methanolic fruit extract of Solanum indicum (SIE) in streptozotocin (STZ) induced diabetic rats. Experimentally, type II diabetes was induced in rats by an i.p. injection of STZ at a dose of 60 mg/kg. The effect of the fruit extract was evaluated at doses of 100 and 200 mg/kg body weight in STZ-induced diabetic rats for 30 days. The oral administration of fruit extract caused a significant (p < 0.05) reduction in the blood glucose level with a more prominent effect at 200 mg/kg. The fruit extract showed dose-dependent α-amylase and α-glycosidase inhibitory activity. It reduced the serum cholesterol and triglyceride levels remarkably in diabetic rats compared to normal. The extract showed the reduced activity of endogenous antioxidants, superoxide dismutase, glutathione peroxidase and catalase in the liver of STZ diabetic rats. The result confirmed that the fruit extract of Solanum indicum showed a dose-dependent blood glucose lowering effect and significantly reduced elevated blood cholesterol and triglycerides. It prevented oxidative stress associated with type II diabetes in STZ rats.

In Vitro α-Amylase and α-Glucosidase Inhibitory Activity of Green Seaweed Halimeda tuna Extract from the Coast of Lhok Bubon, Aceh.

Seaweed belongs to marine biota and contains nutrients and secondary metabolites beneficial for health. This study aimed to determine the antidiabetic activity of extracts and fractions of green seaweed Halimeda tuna. The H. tuna sample was extracted with the maceration method using methanol and then partitioned using ethyl acetate and water to obtain ethyl acetate and water fractions. The methanol extract, ethyl acetate fraction, and water fraction of H. tuna were tested for their inhibitory activity against α-amilase and α-glucosidase. The methanol extract and the fractions with the highest inhibitory activity were phytochemically tested and analyzed using gas chromatography-mass spectrometry (GC-MS). The results showed that the ethyl acetate fraction (IC50 = 0.88 ± 0.20 mg/mL) inhibited α-amylase relatively similar to acarbose (IC50 = 0.76 ± 0.04 mg/mL). The methanol extract (IC50 = 0.05 ± 0.01 mg/mL) and the ethyl acetate fraction (IC50 = 0.01 ± 0.00 mg/mL) demonstrated stronger inhibitory activity against α-glucosidase than acarbose (IC50 = 0.27 ± 0.13 mg/mL). Phytochemical testing showed that the methanol extract and the ethyl acetate fraction contained secondary metabolites: alkaloids, flavonoids, steroids, and phenol hydroquinone. The compounds in methanol extract predicted to have inhibitory activity against α-amylase and α-glucosidase were Docosanol, Neophytadiene, Stigmasta-7,22-dien-3-ol,acetate,(3.beta.,5.alpha.,22E), Octadecanoic acid,2-oxo-,methyl ester, and phytol, while those in the ethyl acetate fraction were n-Nonadecane, Phytol, Butyl ester, 14-.Beta.-H-pregna, Octadecenoic acid, and Oleic acid.

Glycation of whey protein isolate and stachyose modulates their in vitro digestibility: Promising prebiotics as functional ingredients

Glycated conjugates have recently been designed to be targeted to probiotic in the colon. However, the underlying mechanisms of regulating the prebiotic properties and digestibility of conjugates through glycation have not been fully elucidated. In this study, WPI-stachyose conjugates were prepared through Maillard reaction and proposed as functional ingredients with prebiotic characteristics. The effect of glycation on the in vitro simulated gastrointestinal fate of WPI-stachyose conjugate was further evaluated. The results showed that the glycated conjugates of stachyose covalently bound to whey protein exhibited a characteristic cross-linked structure, which enhanced their inhibition of α-amylase activity and retardation of glucose dialysis. Besides, simulated digestion analysis demonstrated that stachyose-conjugated WPI was more resistant to pepsin and trypsin digestion than unconjugated WPI. Compared with native WPI, the protein digestibility and degree of hydrolysis of WPI-stachyose conjugates were reduced by 12.5% ± 0.66% and 5.30% ± 1.02%, respectively. In addition, rat intestinal extracts were used to detect the in vitro digestibility of stachyose. The hydrolysis rate of stachyose in the glycated conjugates was 70% lower than that of stachyose. Therefore, the resulting WPI-stachyose conjugate may be used as functional ingredients to achieve the sustained-release effect in the gastrointestinal tract. These findings demonstrate the possibility of modulating proteins and carbohydrates digestibility through glycation, and have implications for the design and manufacture of potential prebiotic molecules with controlled digestibility in food and related healthcare fields.

Potential anti-obesity effect of fermented adzuki beans and their untargeted metabolomics using UHPLC-QTOF-MS

Nowadays, obesity is an ultimate public health problem worldwide. However, medical and surgical treatment methods for alleviating obesity can cause multiple adverse side effects. Therefore, in the present study, we evaluated the potential anti-obesity effect of five seeds buckwheat, pea, soybean, red kidney bean, and adzuki beans cultivated in South Korea. Anti-obesity screening of seeds showed adzuki beans with the highest lipase (77.2%) and α-amylase (60.5%) inhibitory activity. Later, adzuki beans were fermented using different lactic acid bacteria (LABs). After fermentation, Pediococcus acidilactici fermented adzuki beans displayed significant anti-obesity ability, showing the half maximal inhibitory concentration (IC50) of lipase (from 1.908 to 0.839 mg/mL) and α-amylase (from 0.6873 to 0.379 mg/mL) decreased markedly compared to raw adzuki beans. UHPLC-QTOF-MS was applied to investigate metabolites and their metabolic responses during fermentation. The omics results identified 121 differentially expressed metabolites belonging to organic acids, polyphenols, amino acids and alkaloids. Furthermore, pathway enrichment revealed that P. acidilactici fermentation mainly affected fatty acid, biotin metabolism and alkaloid biosynthesis pathway, which could contribute to the promoting anti-obesity properties of adzuki beans. The metabolomics methods provide novel insights into the metabolic pathway regulation of adzuki beans in response to improving anti-obesity ability after fermentation. These findings suggest that fermenting adzuki beans with P. acidilactici might be a promising method for developing functional foods with anti-obesity properties.

Comparing and contrasting different herbal products intended for the management of obesity approved in the Palestinian markets

BackgroundThe use of conventional medical therapies has proven to have many setbacks and safety concerns that need further improvement. However, herbal medicine has been used for over 2000 years, and many studies have proven the use of herbs to be effective and safe. This article discussed the efficacy of different herbal products used in the management of obesity. To evaluate the efficacy of seven herbal-based weight loss products currently available on the Palestinian market, using in vitro assays to screen for antioxidants, anti-amylase, and anti-lipase effects for each product.MethodPancreatic lipase and salivary amylase inhibitory activities, as well as antioxidant analysis, were tested in vitro on a variety of herbal products. Then the IC50 was measured for each test.ResultsThe anti-lipase assay results, IC50 values in (μg/mL) of each of the seven products (Product A, product B, product C, product D, product E, product F, and product G) were 114.78, 532.1, 60.18, 53.33, 244.9, 38.9, and 48.97, respectively. The IC50 value for orlistat (Reference) was 12.3 μg/ml. On the other hand, the IC50 value for alpha amylase inhibition of the seven products (Product A, product B, product C, product D, product E, product F, and product F) were 345.93, 13,803.84 (Inactive), 73.79, 130.91, 165.95, 28.18, and 33.11 μg/ml respectively, while acarbose (Reference) was 23.38 μg/ml. The antioxidant activity (IC50 values) for the seven products (Product A, product B, product C, product D, product E, product F, and product F) were 1258.92, 707.94, 79.43, 186.20, 164.81, 17.53, and 10.47 μg/ml respectively. While the IC50 value for Trolox was 2.70 μg/ml.ConclusionIt can be concluded that the seven products showed varied anti-lipase, anti-amylase, and antioxidant effects. However, products F and G showed superiority in all categories.

New arylidene-linked chromane-2,4-dione analogs as potential leads for diabetic management; syntheses, α-amylase inhibitory, and radical scavenging activities

New arylidene-linked chromane-2,4-dione analogs as potential leads for diabetic management; syntheses, α-amylase inhibitory, and radical scavenging activities

Moxifloxacin Metal Complexes: Synthesis, Characterisation, Antimicrobial and Antidiabetic Activities with Docking Studies

Six new metal complexes of Fe(III), Cu(II), and Hg(II) were synthesised, i.e., three (2, 4, and 5) with moxifloxacin (mono-ligand) and the other three (1, 3 and 6) with moxifloxacin and hydrazine (biligand). These were characterised through UV-Vis, FT-IR, elemental analysis (CHN), atomic absorption spectroscopy, TGA, scanning electron microscopy (SEM), and powder XRD studies. Further, all of these compounds were screened for their antimicrobial, cytotoxic, and antidiabetic potential. The study revealed that the synthesised metal complexes possess an excellent ability to become antifungal agents compared to moxifloxacin. Additionally, the cytotoxicity of compounds 1, 3, and 4 was in the acceptable range with much better antidiabetic potential as compared to the ligand moxifloxacin. Interestingly, the α-amylase inhibition activity of complexes 1 and 3 was found very close to the standard drug acarbose. Furthermore, the computational studies also authenticate the results of the antidiabetic potential of complexes 1, 3, and 4 by presenting the necessary interactions of these compounds with their respective binding sites. The overall results indicate that the antifungal and antidiabetic ability of moxifloxacin is enhanced significantly by complexation with the given metals and the secondary ligand, thereby making it a suitable lead compound for yet another avenue of an antifungal and antidiabetic agent in the field of drug discovery and development.

In Vitro α-Amylase, α-Glucosidase, Pancreatic Lipase, Xanthine Oxidase Inhibiting Activity of Agaricus bisporus Extracts

In this study, the α-amylase inhibitory activity, α-glucosidase inhibitory activity, pancreatic lipase inhibitory activity, and Xanthine Oxidase inhibitory activity of the fruiting body extracts of 5 varieties of Agaricus bisporus (AB) were confirmed. First, the α-amylase inhibitory activity of AB12, AB13, AB18, AB34, and AB40 methanol extracts was lower than that of acarbose, a positive control, in all concentration ranges. The α-glucosidase inhibitory activity of the AB40, AB13, and AB12 methanol extracts at the extract concentration of 1.0 mg/mL was 80.5%, 81.3%, and 78.5%, respectively, similar to that of acarbose, a positive control. The pancreatic lipase inhibitory activity of the methanol extract of Agaricus bisporus fruiting body was significantly lower than that of the positive control orlistat in the concentration range of 50 ∼ 1.000 (mg/mL). The Xanthine Oxidase inhibitory activity was 0.5 ∼ 8.0 mg/mL of each extract, which was significantly lower than that of the positive control allopurinol in the same concentration range. However, the Xanthine Oxidase inhibitory activity of AB13 and AB40 at 8.0 mg/mL was about 70%, which was higher than that of other mushrooms. In conclusion, five kinds of Agaricus bisporus fruiting bodies seem to have inhibitory effects on enzymes such as α-amylase, α-glucosidase, pancreatic lipase, and Xanthine Oxidase that degrade starch and protein. In particular, it has an inhibitory effect and a reduction effect on xanthine oxidase that causes gout, so it is expected that it can be developed and used as a food or health supplement with health functional properties through future research.

Influence of Post-Harvest Drying Processes on the Composition and Biological Activities of Essential Oils from Leaves of Camphor Tree from Uttarakhand Himalaya, India

Cinnamomum camphora L. belonging to family Lauraceae, is an aromatic evergreen plant which has been traditionally used to heal several health problems such as cold, fever, pneumonia, diarrhea and various infections. In this study, four drying treatments (sun, shade, blower and oven) were applied on the leaves of C. camphora collected in summer season and their effect on the yield, composition and biological properties of the essential oil was evaluated. Hydro distillation of fresh and dried samples was carried out by Clevenger apparatus and essential oils obtained were analyzed by GC and GC/MS. Alpha-pinene, camphene, myrcene, limonene and camphor were the common major constituents of the essential oils. The highest essential oil yield was obtained by blower drying technique. Shade dried sample possessed the best antioxidant, antiinflammatory and α-amylase inhibition activities. The highest percentage of camphor was obtained in sun dried plant material. Despite of comparatively low essential oil yield in sun dried C. camphora, sun drying technique is less energy consuming and increased the content of major component of camphora leaves.

Chemical Constituents from the Leaves of Ligustrum robustum and Their Bioactivities

The leaves of Ligustrum robustum have been consumed as Ku-Ding-Cha for clearing heat and removing toxins, and they have been used as a folk medicine for curing hypertension, diabetes, and obesity in China. The phytochemical research on the leaves of L. robustum led to the isolation and identification of two new hexenol glycosides, two new butenol glycosides, and five new sugar esters, named ligurobustosides X (1a), X1 (1b), Y (2a), and Y1 (2b) and ligurobustates A (3a), B (3b), C (4b), D (5a), and E (5b), along with seven known compounds (4a and 6-10). Compounds 1-10 were tested for their inhibitory effects on fatty acid synthase (FAS), α-glucosidase, and α-amylase, as well as their antioxidant activities. Compound 2 showed strong FAS inhibitory activity (IC50 4.10 ± 0.12 μM) close to that of the positive control orlistat (IC50 4.46 ± 0.13 μM); compounds 7 and 9 revealed moderate α-glucosidase inhibitory activities; compounds 1-10 showed moderate α-amylase inhibitory activities; and compounds 1 and 10 displayed stronger 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) ammonium salt (ABTS) radical scavenging effects (IC50 3.41 ± 0.08~5.65 ± 0.19 μM) than the positive control l-(+)-ascorbic acid (IC50 10.06 ± 0.19 μM). This study provides a theoretical foundation for the leaves of L. robustum as a functional tea to prevent diabetes and its complications.

Identification of sesquiterpene glycosides from Dendrobium nobile and their α-glycosidase and α-amylase inhibitory activities

Dendrobium nobile is a traditional Chinese medicine and functional food in China, with anti-aging, immunity-enhancing, glucose-lowering and lipid-lowering health functions. In recent years, the research value of D. nobile has attracted the attention of more and more experts and scholars. Today, phytochemical investigation of the stems of Dendrobium nobile Lindl., led to the isolation of five sesquiterpene glycosides, including dendromoniliside D (1), dendronobiloside A (2), dendronobiloside C (3), dendronobiloside D (4), dendroside G (5) and their α-amylase and α-glycosidase inhibitory activities were also investigated. Among them, dendromoniliside D (1), dendroside G (5) were first isolated from D. nobile. And dendronobiloside A (2) and dendronobiloside C (3) exhibited better inhibitory activity against α-glycosidases, respectively. In the case of α-amylase inhibition, dendroside G (5) has a relatively good effect. These results suggest that sesquiterpene glycosides of D. nobile have potential hypoglycemic activity and deserve further research and development.

Thermosonication as a pretreatment of raw milk for Minas frescal cheese production.

Minas frescal cheese is extremely popular in Brazil, with high perishability and acceptability. Among emerging technologies, ultrasound stands out for its satisfactory results regarding microbiological safety and technological and sensory aspects. The combined mild temperature application, called thermosonication, can generate even more promising results. In this study, a high-intensity ultrasound system combined with thermal heating (TS, thermosonication) was applied for the treatment of raw milk to produce Minas Frescal cheese. US energy was delivered to raw milk samples using a probe operating at a 20kHz of frequency and nominal power of 160, 400, and 640W. The TS system was compared with conventional pasteurization (HTST, high-temperature short-time pasteurization) at 72 to 75°C and 15s. Soft cheeses were prepared with different samples: (a) raw milk (control), b)conventionally pasteurized milk (HTST), and c) TS treat milk in different nominal power (TS160, TS400, and TS640). The produced cheeses were evaluated for microbiological behavior, rheology, color parameters, and bioactive compounds. TS treatment in milk resulted in higher microbial inactivation and stability during storage, improved color parameters (higher lightness (L*), and whiteness index (WI). TS treatment also showed a higher generation of bioactive compounds (higher antioxidant, and inhibitory activities of α-amylase, α-glucosidase, and angiotensin-converting enzymes) than HTST. The impact of TS on rheological properties was similar to HTST, resulting in more brittle and less firm products than the cheese produced with raw milk. The positive effects were more prominent using a nominal power of 400W (TS400). Therefore, TS proved to be a promising process for processing milk for Minas Frescal cheese production.

Physicochemical properties and anti-diabetic ability of polysaccharides from a thinned peach fruit.

Thinned peach fruit is a by-product with abundant yields. However, it is barely utilized. This study aimed to study the physicochemical properties and anti-diabetic ability of polysaccharides (PPSs) from a thinned peach fruit to investigate its application potential. Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM) characterizations were performed together with tests to determine rheology properties, monosaccharide composition, and molecular weight of the obtained polysaccharide. Moreover, the antioxidant activity, α-amylase inhibitory activity, binding abilities to bile salts, and effects on type 2 diabetic mice were analyzed. The results indicated that PPS consisted of two components with molecular weights of 287.38 kDa and 12.02 kDa, accounting for 89.83% and 10.17% of the composition, respectively. The dominant monosaccharides were galactose, galacturonic acid, and arabinose, exhibiting α-configurations. The concentration was positively related to the viscosity of PPS. As the temperature was increased from 25 °C to 37 °C and the pH from 2.0 to 7.0, the viscosity decreased. The IC50 values for scavenging DPPH and ABTS were around 0.22 and 1.47 mg mL-1. Also, PPS could inhibit α-amylase ability and bind bile salts. The administration of PPS significantly inhibited emaciation, organ damage, improved oral glucose tolerance and insulin resistance, enhanced the content of short-chain fatty acids (SCFAs), and regulated blood lipid profiles and the composition and structure of colon microbiota in type-2 diabetic mice. These results provide new evidence for the potential of PPS as a bioactive ingredient with anti-diabetic properties for use in the food industry.

No correlation between amylase/trypsin-inhibitor content and amylase inhibitory activity in hexaploid and tetraploid wheat species

Wheat amylase/trypsin-inhibitors (ATI) are known triggers for wheat-related disorders. The aims of our study were to determine (1) the inhibitory activity against different α-amylases, (2) the content of albumins and globulins (ALGL) and total ATI and (3) to correlate these parameters in wholegrain flour of hexaploid, tetraploid and diploid wheat species.The amount of ATI within the ALGL fraction varied from 0.8% in einkorn to 20% in spelt. ATI contents measured with reversed-phase high-performance liquid chromatography (RP-HPLC) revealed similar contents (1.2–4.2 mg/g) compared to the results determined by LC-MS/MS (0.2–5.2 mg/g) for all wheat species except einkorn. No correlation was found between ALGL content and inhibitory activity. In general, hexaploid cultivars of spelt and common wheat had the highest inhibitory activities, showing values between 897 and 3564 AIU/g against human salivary α-amylase. Tetraploid wheat species durum and emmer had lower activities (170–1461 AIU/g), although a few emmer cultivars showed similar activities at one location. In einkorn, no inhibitory activity was found. No correlation was observed between the ATI content and the inhibitory activity against the used α-amylases, highlighting that it is very important to look at the parameters separately.

Novel hybrids of thiazolidinedione-1,3,4-oxadiazole derivatives: synthesis, molecular docking, MD simulations, ADMET study, in vitro, and in vivo anti-diabetic assessment.

As compared to standard medicinal compounds, hybrid molecules that contain multiple biologically active functional groups have greater affinity and efficiency. Hence based on this concept, we predicted that a combination of thiazolidinediones and 1,3,4-oxadiazoles may enhance α-amylase and α-glucosidase inhibition activity. A series of novel 3-((5-phenyl-1,3,4-oxadiazol-2-yl)methyl)thiazolidine-2,5-dione derivatives (5a-5j) were synthesized and characterized using different spectroscopic techniques i.e., FTIR, 1H-NMR, 13C-NMR and MS. To evaluate in silico, molecular docking, MMGBSA, and MD simulations were carried out which were further evaluated via in vitro inhibition of α-amylase and α-glycosidase enzyme inhibition assays. In addition, the in vivo study was performed on a genetic model of Drosophila melanogaster to assess the antihyperglycemic effects. The compounds (5a-5j) demonstrated α-amylase and α-glucosidase inhibitory activity in the range of IC50 values 18.42 ± 0.21-55.43 ± 0.66 μM and 17.21 ± 0.22-51.28 ± 0.88 μM respectively when compared to standard acarbose. Based on the in vitro studies, compounds 5a, 5b, and 5j were found to be potent against both enzymes. In vivo studies have shown that compounds 5a, 5b, and 5j lower glucose levels in Drosophila. These compounds could be further developed in the future to produce a new class of antidiabetic agents.

Antidiabetic effects of protein hydrolysates from Trachinotus ovatus and identification and screening of peptides with α-amylase and DPP-IV inhibitory activities

In the present study, the antidiabetic properties of Trachinotus ovatus protein hydrolysates (TOH) in streptozotocin-induced diabetic mice were investigated, and peptides with α-amylase (AAM) and dipeptidyl peptidase IV (DPP-IV) inhibitory activities were identified and screened. The results showed that TOH alleviated body weight loss, polyphagia, blood glucose elevation and insulin secretion decline in diabetic mice. After 4 weeks of TOH administration, random blood glucose (RBG) decreased significantly. The TOH groups showed a dose-dependent reduction in fasting blood glucose (FBG), especially in the high-dose TOH group, which reduced FBG by 58% versus the effect of metformin. Moreover, TOH exerted a remarkable protective effect on hepatorenal function, as evidenced by increased superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) and decreased serum urea levels. Histopathological studies confirmed that TOH can significantly protect the kidney and pancreas from histological changes, which was of great benefit for ensuring the normal secretion of insulin and preventing the occurrence of complications such as diabetic nephropathy. Two fractions with higher inhibitory activity against AAM and DPP-IV, F4 and F6, were obtained from the ultrafiltration of TOH-2 (≤3 kDa). A total of 19 potentially active peptides from F4 and 3 potentially active peptides from F6 were screened by LC‒MS/MS combined with bioinformatic analysis. These peptides are small molecular peptides composed of 2–6 amino acids, rich in characteristic amino acids such as proline, arginine, phenylalanine and asparagine, and contain high proportions of peptides (68% for F4, 67% for F6) with hydrophobicity ≥50%. They offer potent antidiabetic potential and could potentially bind to the active sites in the internal cavities of the target enzymes AAM and DPP-IV. In summary, this study revealed for the first time the antidiabetic effects of protein hydrolysates of Trachinotus ovatus and their derived peptides, which are promising natural ingredients with the potential to be used for the treatment or prevention of diabetes.