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This study aimed to optimize subcritical water extraction process, characterize chemical composition and investigate the biological activities of Nitraria sibirica Pall. (NSP) anthocyanin. Overall, the optimization was achieved under following conditions: extraction temperature 140 °C, extraction time 45 min and flow rate 7 mL/min with the extraction yield of 1.075 mg/g. 3 cyanidin, 3 petunidin, 1 delphinidin and 1 pelargonidin compounds were identified in the anthocyanic extract from NSP via UPLC–Triple–TOF–MS/MS. NSP anthocyanin exhibited better DPPH free-radical scavenging activity than ascorbic acid. It displayed superior α-glucosidase inhibition activity, which was ∼14 times higher than that of acarbose. Moreover, enzyme kinetics results indicated that NSP anthocyanin behaved as a reversible, mixed-type inhibitor. Molecular docking and molecular dynamics simulation results revealed that NSP anthocyanin interacted with α-glucosidase mainly via van der Waals forces, hydrogen bond and possessed fairly stable configuration. Therefore, NSP anthocyanin is a promising α-glucosidase inhibitor for diabetes mellitus.

Objective: The purpose of this study was to compare the activity difference of polyphenols in banana pulp of different varieties and to provide scientific basis for the exploitation and utilization of banana pulp polyphenols. Methods: Five banana pulp polyphenols were extracted by ultrasonic extraction, and the phenolic components were analyzed by ultra-high performance liquid chromatography （UHPLC）. The antioxidant capacity and inhibition ability of α-glucosidase were determined. Results: The total polyphenols, flavonoids and tannins content were significant differences among five varieties （P＜0.05）. Eight phenolic compounds were identified in five banana pulps, including four phenolic acids and their derivatives, and four flavonoid compounds. The five kinds of banana pulp polyphenols had certain antioxidant activities of scavenging DPPH, ABTS free radical, and reducing iron ion. All the five kinds of banana pulp polyphenols could inhibit α-glucosidase. The major bioactive components in banana pulp, catechin acid and rutin, were signiflcantly positively correlated with the ability of α-glucosidase inhibition （P＜0.05）. The antioxidative ability and inhibitory activity of α-glucosidase were the strongest in the pulp polyphenols of Nanjiao No.42 banana. The enzyme activity was inhibited by mixed inhibition, and the interaction with α-glucosidase was exothermic. Conclusion: Banana pulp polyphenols have good antioxidant ability and inhibition ability to α-glucosidase activity, and are expected to be a good selective inhibitor of α-glucosidase.

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Maize proteins are considered of low nutritional value, these proteins when hydrolyzed become a good source of peptides with important biological activity and can be used as supplements or food additives. The objective of this research was to prepare bioactive fractions of maize proteins and evaluate the effect of digestive enzymes (pepsin and pancreatin), temperature and pH on their antioxidant, hypoglycemic activities and their techno-functional properties. In a first stage, the biological activities of total protein hydrolysates of maize, zeins and non-zeins were evaluated. It was observed that the hydrolysate with the highest values of antioxidant (ABTS = 37.09%; DPPH = 33.76%) and hypoglycemic (α-amylase = 46.14%: α-glucosidase = 46.80%) activity was the total protein hydrolysate. In a second stage, the total protein hydrolyzate was fractionated by ultrafiltration to obtain four fractions of different molecular weight (> 10 kDa, 5–10 kDa, 3–5 kDa, and < 3 kDa). The fraction < 3 kDa stood out for presenting better values of ABTS (64.68%), DPPH (40.09%), α-amylase (55.22%) and α-glucosidase (37.21%). This fraction conserved its biological activity when subjected to gastrointestinal digestion and sudden changes in temperature and pH. In addition, this fraction has good techno-functional properties and could be used as a supplement or additive in food formulation. [ABSTRACT FROM AUTHOR]

Flos Sophorae Immaturus (FSI) contains a large number of bioactive substances with antioxidant and hypoglycaemic activity. However, a feasible drying process plays an important role in the retention of its biological activity. The present work investigated the effects of ultrasound-assisted vacuum drying (UAVD) on FSI samples in terms of drying time, colour, microstructure, and total flavonoid content (TFC). Meanwhile, the antioxidant activity and α-glucosidase inhibition activity were also evaluated. The results show that the drying time of UVAD samples was decreased by 40% compared to that of the single vacuum-dried (VD) samples (600 W for 10 min). The cellular porous structures of FSI tissue were formed by UAVD, which promoted the migration of water from the inside to the outside. Furthermore, samples treated by UAVD exhibited better antioxidant activities and α-glucosidase and α-amylase inhibition capacities, with DPPH (81.86%), ABTS (88.61%), FRAP (83.05%), α-glucosidase inhibition capacity (89%), α-amylase (85%), drying time (3 h), and total aberration (ΔE) (1.63) being the highest characteristic traits. In this condition, the highest levels of total flavonoid content (TFC), rutin, quercetin, kaempferol, isorhamnetin, and genistein were obtained with 266.94, 239.46, 35.56, 8.54, 10.37, and 5.64 mg/g DW, respectively. The results confirm that UAVD is a novel method that significantly reduced the VD time and promoted the release of the bioactive substances of FSI. [ABSTRACT FROM AUTHOR]

Plant-derived phytochemicals have recently drawn interest in the prevention and treatment of diabetes mellitus (DM). The seeds of Moringa oleifera Lam. are widely used in food and herbal medicine for their health-promoting properties against various diseases, including DM, but many of their effective constituents are still unknown. In this study, 6 new phenolic glycosides, moringaside B–G (1–6), together with 10 known phenolic glycosides (7–16) were isolated from M. oleifera seeds. The structures were elucidated by 1D and 2D NMR spectroscopy and high-resolution electrospray ionization mass spectrometry (HR-ESI-MS) data analysis. The absolute configurations of compounds 2 and 3 were determined by electronic circular dichroism (ECD) calculations. Compounds 2 and 3 especially are combined with a 1,3-dioxocyclopentane moiety at the rhamnose group, which are rarely reported in phenolic glycoside backbones. A biosynthetic pathway of 2 and 3 was assumed. Moreover, all the isolated compounds were evaluated for their inhibitory activities against α-glucosidase. Compounds 4 and 16 exhibited marked activities with IC50 values of 382.8 ± 1.42 and 301.4 ± 6.22 μM, and the acarbose was the positive control with an IC50 value of 324.1 ± 4.99 μM. Compound 16 revealed better activity than acarbose.

Objectives: Uncariae Rammulus Cum Uncis (URCU) is a commonly used herbal medicine to treat diabetes. This work is aimed to discover and identify the antidiabetic components from URCU extract. Methods: Column chromatography and recrystallisation were used to separate individual compounds from URCU extract, and the obtained individual compounds were used for determination of α‐glucosidase inhibitory activity. Molecular docking was applied to predict the molecular interactions. High‐performance liquid chromatography (HPLC) was used for fingerprint analysis of 12 batches of URCU. HPLC fingerprints were assessed by the similarity analysis (SA) and hierarchical clustering analysis (HCA). The spectrum–effect relationship analysis of URCU was assessed by orthogonal partial least squares (OPLS) and bivariate correlation analysis (BCA). Results: A total of 10 potential bioactive compounds were isolated and six of them showed potent α‐glucosidase inhibitory activity (IC50 = 4.21–166.10 μM). The molecular docking results revealed that the binding energy was consistent with the results of α‐glucosidase inhibition activity analysis (−8.55 to −4.84 kcal/mol). The ethanol extracts of the 12 batches of URCU showed inhibitory effect on α‐glucosidase in a dose‐dependent manner, and the IC50 values ranged from 0.94 μg/mL to 12.57 μg/mL. The spectrum–effect relationship analysis results indicated that 13 peaks might be potential antidiabetic compounds in URCU, including 18 (hyperoside) and 19 (rutin). Conclusion: A comprehensive connection between URCU chemical components and α‐glucosidase inhibitory activity was established for the first time by using a spectrum–effect relationship model, which might be applicable to the quality control of URCU. The spectrum‐effect relationship of URCU extracts on inhibition of α‐glucosidase was firstly molded by OPLS and BCA. Ten potential bioactive compounds were isolated, and six compounds had α‐glucosidase inhibitory activity. Thirteen peaks including hyperoside and rutin might be potential antidiabetic compounds in URCU. [ABSTRACT FROM AUTHOR]

In our current investigation, 37 constituents (1–37), including 11 megastigmanes (1–11), 17 flavonoids (12–28) and 9 phenylpropanoids (29–37), were isolated from a 70%-EtOH extract of Diaphragma juglandis Fructus. Among them, compounds 1–3, 12 and 29 were new compounds and their structures were elucidated on the basis of physicochemical evidence and meticulous spectroscopic analysis (NMR, HRESIMS and CD). Compounds 13, 16, 21 and 28 showed moderate inhibitory effect on α-glycosidase inhibitory activities, with IC50 values being in the range of 29.47–54.82 µM and stronger than the positive control (acarbose, 60.01 ± 4.82 µM). [ABSTRACT FROM AUTHOR]

Flos Sophorae Immaturus (FSI) contains a large number of bioactive substances with antioxidant and hypoglycaemic activity. However, a feasible drying process plays an important role in the retention of its biological activity. The present work investigated the effects of ultrasound-assisted vacuum drying (UAVD) on FSI samples in terms of drying time, colour, microstructure, and total flavonoid content (TFC). Meanwhile, the antioxidant activity and α-glucosidase inhibition activity were also evaluated. The results show that the drying time of UVAD samples was decreased by 40% compared to that of the single vacuum-dried (VD) samples (600 W for 10 min). The cellular porous structures of FSI tissue were formed by UAVD, which promoted the migration of water from the inside to the outside. Furthermore, samples treated by UAVD exhibited better antioxidant activities and α-glucosidase and α-amylase inhibition capacities, with DPPH (81.86%), ABTS (88.61%), FRAP (83.05%), α-glucosidase inhibition capacity (89%), α-amylase (85%), drying time (3 h), and total aberration (ΔE) (1.63) being the highest characteristic traits. In this condition, the highest levels of total flavonoid content (TFC), rutin, quercetin, kaempferol, isorhamnetin, and genistein were obtained with 266.94, 239.46, 35.56, 8.54, 10.37, and 5.64 mg/g DW, respectively. The results confirm that UAVD is a novel method that significantly reduced the VD time and promoted the release of the bioactive substances of FSI.

Salak (Salacca zalacca) is well-known as snake fruit and it is immensely studied for its antioxidative and antidiabetic active metabolites throughout the southeast Asian countries. However, there are many remaining unidentified metabolites due to very low abundance and natural variation, which need to be further explored. Nowadays mass spectrometry (MS/MS) facilitates the tentative identification of unknown compounds in the crude herbal extracts. This study described the metabolite profiling of hydroalcoholic extracts of S. zalacca analysed by LC-QTOF-MS/MS. The 60% ethanolic extract exhibited the highest α-glucosidase inhibition and ferric reducing antioxidant power activities with IC50 of 15.94 µg/mL and 78.13 μg AAE/g, respectively. Multivariate data analysis (MVDA) by an orthogonal partial least-squares (OPLS) algorithm was conducted to correlate the α-glucosidase inhibition activity with the LC- QTOF-MS data. A total of 4 compounds were reported for first time in this fruit and identified based on the molecular mass and fragment ions. LC-QTOF-MS analysis indicated the presence of carexane I, 5-phenoxytetrazol-1-yl)-2,3,5,6-hexahydrofurofuran-3-ethylurea, 3-acetylphenoxy)-N-[(2)-1-amino-4-methyl-1-oxopentan-2-yl]-4,5-dihydroxycyclohexene-1-carboxamide and Ethyl 4-[5-methyl-2-oxo-1′,2′,5′,6′,7′,7′a-hexahydro-1H-spiro[indole-3,3′-pyrrolizine]-2′-ylamido] benzoate. Molecular docking of those compounds with the α–glucosidase enzyme was performed to confirm their antidiabetic potential. These bioactive compounds could be suggested as α-glucosidase inhibitors and functional food additives.

A series of new benzo[d][1,2,3]triazol-1-yl-pyrazole-based dihydro-[1,2,4]triazolo[4,3-a]pyrimidine derivatives 4a-p were synthesized and well characterized by using IR, 1H, 13C NMR and mass spectral data. Finally, the structure of the compound 4l was solved unambiguously by single-crystal X-ray diffraction (SXRD) which confirms all the structures 4a–p. The in vitro α-glucosidase inhibition, anticancer (A549 and MCF-7 cell lines) and antioxidant studies of the title compounds 4a–p were screened. Among all the compounds, 4g, 4h and 4n exhibited significant α-glucosidase inhibition activity with the IC50 values 20.12 ± 0.19 µM, 21.55 ± 0.46 µM and 24.92 ± 0.98 µM. Similarly, the compounds 4h, 4d and 4e showed potent anticancer activity against A549 (human lung carcinoma) cell line with IC50 values 3.64 µM, 4.73 µM and 4.56 µM, respectively, whereas the compounds 4c and 4o displayed potent anticancer activity against human breast cancer (MCF-7) cell line with IC50 values of 2.66 µM and 2.11 µM. In addition, the antioxidant activity revealed that the compounds 4e and 4h exhibited potent antioxidant activity (IC50: 4.25 µM and 5.40 µM). To determine the safety profile of the most active compounds 4c, 4d, 4e, 4g, 4h, 4n and 4o were tested against non-cancer HEK293 cell line (human embryonic kidney 293), results in the lower toxicity of these compounds. New benzo[d][1,2,3]triazol-1-yl-pyrazole-based dihydro-[1,2,4]triazolo[4,3-a]pyrimidines were synthesized. The target compounds were showed significant α-glucosidase inhibition, anticancer and antioxidant activities. [ABSTRACT FROM AUTHOR]

In a search for α-amylase and α-glucosidase inhibitors to treat type II diabetes, a new series of N-(3-acetyl-2-methyl-4-phenylquinolin-6-yl)arylamides were synthesized from 3-acetyl-2-methyl-4-phenylquinolines. Initially, nitro function of 1-(2-methyl-6-nitro-4-phenylquinolin-3-yl) ethanone was converted into the corresponding amine by grinding it with zinc dust and ammonium chloride (reducing agent) which in turn successfully converted into the N-(3-acetyl-2-methyl-4-phenylquinolin-6-yl) arylamides by treating it with coupling reagents such as EDC, HATU, and DCC. All the synthesized compounds were found to afford excellent yields with HATU, moderate in EDC, and very less in DCC and hence, HATU was considered as a suitable coupling reagent. These analogs are structurally characterized by NMR, NMR-DEPT, and HRMS. All the synthesized compounds were evaluated for in-silico and in-vitro α-glucosidase and α-amylase inhibitory activity using acarbose as standard and all the compounds showed positive results by in-silico and in-vitro α-amylase inhibition assay. Among the tested compounds, compound 5c and 5d in α-glucosidase as well as in α-amylase are found to have least binding energy value. These compounds found to form more stable ligand–receptor complex amongst other compounds. In addition, in experimental part, also the compounds 5c and 5d exhibited 56.90 ± 0.77% and 59.46 ± 0.61% of the higher potent α-glucosidase inhibitory activity with IC50 values 171.75 ± 3.95 µmol/mL and 171.67 ± 1.57 µmol/mL significantly (p < 0.05) compared to the remaining seven test samples. And similarly, the compound 5c and 5d possessed α-amylase inhibitory activity at a concentration of 100 µg/mL (55.42 ± 0.42% and 55.42 ± 1.14%) with IC50 values 138.92 ± 4.44 µmol/mL and 158.78 ± 2.34 µmol/mL. [ABSTRACT FROM AUTHOR]

Six pairs of enantiomeric dilignans, (+)/(−)-magdiligols A–F, have been isolated from an ethanolic extract of the barks of Magnolia officinalis var. biloba. Their chemical structures were elucidated by extensive spectroscopic analyses, NMR calculation with DP4+ analysis, and the electronic circular dichroism spectra calculation. (+)/(−)- 1 – 3 possessed a dihydrobenzopyran ring, while a propyl chain of 1 was linked via ether bond. (+)/(−)-Magdiligols D and E ((+)/(−)- 4 and 5) were dilignans possessing a furan ring. (+)-Magdiligol B ((+)/(−)- 2), (+)/(−)-magdiligol C ((+)/(−)- 3), and racemes 2 , 3 , and 5 showed potential hepatoprotective effects against APAP-induced HepG2 cell damage, increased the cell viability from 65.4% to 72.7, 78.7.76.6, 73.9, 77.9 and 73.2%, via decreasing the level of the live enzymes ALH and LDH consistently. (+)/(−)-Magdiligols B–D ((+)/(−)- 2 – 4) and (+)/(−)-magdiligol F ((+)/(−)- 6) exhibited significant antioxidative activity. (+)/(−)-Magdiligols B–C ((+)/(−)- 2 and 3), (−)-magdiligol D ((−)- 4), and (+)-magdiligol E ((+)- 5) displayed significant PTP1B inhibitory activity with IC 50 values 1.41–3.42 μM. (+)/(−)-Magdiligol B ((+)/(−)- 2), and its raceme (2) demonstrated α -glucosidase inhibitory activity with the IC 50 values 1.47, 2.88 and 1.85 μM, respectively. Six pairs of enantiomeric dilignans, (+)/(−)-magdiligols A–F, were chiral-separated from the barks of Magnolia officinalis var. biloba. Some isolates showed excellent hepatoprotective activity, anti-oxidative effect and hypoglycemic activity in vitro. [Display omitted] • Six pairs of enantiomeric dilignans from the barks of M. officinalis var. biloba. • (+)-Magdiligol B and (+)/(−)-magdiligol C showed potential hepatoprotective effects via decreasing the level of the live enzymes ALH and LDH consistently in vitro. • Some isolated diligans displayed significant antioxidative, PTP1B and α -glucosidase inhibitory activity. • (+)/(−)-Magdiligols B–C, (−)-magdiligol D, and (+)-magdiligol E displayed significant PTP1B and α -glucosidase inhibitory activity. [ABSTRACT FROM AUTHOR]

Polyphenols and polysaccharides, as natural bioactive compounds from common fresh fruits, are concerned in reducing risk of developing obesity and diabetes for human in recent years. The content of polyphenol and polysaccharide, their bioactivities among 22 fruit juices were investigated before and after in vitro gastrointestinal digestion in present study. After digestion, contents of polyphenol, polysaccharide and their antioxidant activity, the inhibitory activity of α-amylase and α-glucosidase significantly increased. Punica granatum Linn and Actinidia globosa C. F. Liang displayed maximal increment up to 2, 0.25 and 1.6 fold in contents of polyphenols and polysaccharides, and the inhibitory activity of α-amylase, respectively. The correlation coefficient between contents and inhibitory activity of α-amylase increased in range of 0.002 to 0.485. Lycopersicon esculentum Mill and Pyrus bretschneideri Rehd exhibited maximum increase in the inhibitory activity of α-glucosidase with lowest contents of polyphenols and polysaccharides. The results indicated that polyphenols and polysaccharides digested synergistically contributing to the inhibitory α-amylase activity, and other responsibly bioactive ingredients for inhibitory α-glucosidase activity would be worthy discussed future. The findings above highlighted some potential application of common fruit juices in controlling hyperglycemia and obesity. [ABSTRACT FROM AUTHOR]

A new triterpene glycoside, 3-O-[(α-L-rhamnopyranosyl)(1→2)]-[β-D-glucuronopyranosyl-6-O-methyl ester]-olean-12-ene-28-olic acid (1) and a new indole alkaloid, 5-methoxy-2-oxoindolin-3-acetic acid methyl ester (5) were isolated from the leaves of Acanthopanax senticosus Harms along with six known compounds. The structures of the new compounds were determined by means of 2D-NMR experiments and chemical methods. All the isolated compounds were evaluated for their glycosidase inhibition activities and compound 6 showed significant α-glucosidase inhibition activity.

Six new phragmalin limonoids, named moluccensin Z1 (1), moluccensin Z2 (2), carapanolide Y (3), tabulalin N (4), chukvelutilide A1 (5), and velutinasin J (6), as well as two known compounds, chukvelutilide A (7) and velutinasin D (8) were isolated from the stems of Chukrasia tabularis A. Juss. The structures of the new compounds 1⁻6 were confirmed by spectroscopic methods, including IR and HRESIMS, as well as 1D and 2D NMR, and by comparisons with the data of known analogues. All compounds were tested for α-glucosidase and acetylcholinesterase inhibitory activities. However, none of the compounds was active against α-glucosidase and acetylcholinesterase in vitro.

To explore the chemicals responsible for the health benefits of guava, water-soluble polysaccharides were extracted including GP90 and P90. They exhibited excellent α-glucosidase inhibition activity with an EC 50 of 2.27 μg/mL and 0.18 mg/mL. This suggests that their activities were 1379- and 17-fold higher than the positive control. The DPPH scavenging activities of GP90 was even higher than Vc at some concentrations. Upon further isolation, a novel polysaccharide termed GB90-1B was obtained. Monosaccharide analysis, methylation analysis, and NMR were used to analyze the structural characterization of GB90-1B. Structural analysis revealed that its backbone consisted of (1→5)-linked-α- l -arabinose, (1→2,3,5)-linked-α- l -arabinose and (1→3)-linked-α- l -arabinose. Branch linkages included (1→6)-linked-α- d -glucose, (1→)-linked-α- d -glucose and (1→)-linked-α- l -arabinose. The structure of the repeating unit of GP90-1B was predicted. [ABSTRACT FROM AUTHOR]

Phytochemical investigation on the stems of C. tabularis led to the isolation of five new phragmalin-type limonoids and six known ones. The structures of the new compounds 1-5, named chukbularisins A-E, were elucidated by spectroscopic techniques (IR, HRESIMS, 1D and 2D NMR) and comparisons with published data. All the compounds were evaluated for in vitro α-glucosidase inhibitory activity. Compounds 2, 3, 4, 5, and 8 exhibited inhibitory activity against α-glucosidase with IC50 values of 0.06 ± 0.008, 0.04 ± 0.002, 0.52 ± 0.039, 1.09 ± 0.040, and 0.20 ± 0.057 mM, respectively (using acarbose as positive control, IC50 0.95 ± 0.092 mM). [ABSTRACT FROM AUTHOR]

This study investigated the potential health benefits and functional properties of mango peel powder (MPP) as a source of antioxidants and alpha-glucosidase inhibitors in yoghurts with probiotic bacteria. The study involved plain yoghurt (PY, control), yoghurt fortified with 2% mango peel powder (MY), and yoghurt fortified with 2% MPP and 1% of each probiotic culture of L. casei , L. rhamnosus , B. lactis (MPY). Bioactive potential and individual polyphenols in the products were analysed before and after in vitro gastrointestinal digestion. Results showed that both MY (0.26 ± 0.02 mg/g GAE) and MPY (0.28 ± 0.04 mg/g GAE) had significantly (p ≤ 0.05) higher phenolic contents than PY (0.17 ± 0.02 mg/g GAE). Among the 15 quantified phenolic compounds, quercetin-3-rhamnoside was highest in MPP (432.86 ± 11.02 mg/100g dry wt.), followed by MPY (47.97 ± 1.20) and MY (34.44 ± 2.76 mg/100g fresh wt.). The quantities of the major individual phenolic compounds declined significantly (p < 0.05) in MPP only after gastric digestion, while remained stable in MY and MPY. There were significant (p ≤ 0.05) increments in α-glucosidase inhibition activity (6.06% and 8.47%, in MY and MPY, respectively) post intestinal digestion. The LC-ESI-QTOF-MS/MS analysis of all the sample extracts (undigested and digested) identified a total of 108 phenolic metabolites including 33 phenolic acids, 42 flavonoids, 11 lignans, 3 alkylphenols, 4 coumarins, 3 tyrosols, 1 stilbene, 2 xanthones, 4 phenolic terpene, and 3 tyrosols, 2 hydroxybenzoketones, 1 hydroxybenzaldehyde and 2 other phenolic metabolites. This study provides scientific evidence for the utilization of MPP fortified yoghurts as functional food products. [Display omitted] • Antioxidant characterization of mango peel powder (MPP) and fortified probiotic yoghurts. • Varying trend of liberation of phenolics during simulated digestion in the presence of food matrices. • Enhanced inhibition of α-glucosidase post small intestinal digestion. • Tentative identification of 108 phenolic compounds using LC-ESI-QTOF-MS/MS before and after simulated in vitro digestion. [ABSTRACT FROM AUTHOR]

In the present study antioxidant and antidiabetic potentials of potato peels at two different stages of maturity were evaluated and compared. Peels of young and mature potatoes (YP and MP) were sequentially extracted with hexane (HMP, HYP), ethyl acetate (EMP, EYP) and methanol (MMP, MYP). EMP and EYP were found to possess the highest phenolic content (83.2 and 44.14 mg GAE/g dry weight, respectively) and maximum radical scavenging efficacy for different antioxidant assays performed. EYP demonstrated better α-glucosidase inhibition activity (IC 50 -197.13 µg), intracellular ROS scavenging and induce glucose uptake in L6 rat skeletal muscle cells. Phenolic profiling of compounds (gallic, caffeic, ferulic and chlorogenic acids) in the active extracts were established using HPLC. The study demonstrated that YP exhibited better bioactive potential than that of MP. YP could be an excellent source of bioactive phytochemicals with antioxidant and antidiabetic potential. [ABSTRACT FROM AUTHOR]

Abstract: Aims: One of the aims of this research work is the isolation and identification of various constituents of two medicinally important plants (Iris loczyi and Iris unguicularis). Secondly, the prime aim is the biological evaluation of these natural products to discover new potential inhibitors of α-glucosidase enzyme and protein glycation. Main methods: Plants of the genus Iris contain a variety of secondary metabolites. Chromatographic techniques were applied for the isolation of different compounds from Iris loczyi and Iris unguicularis. All the isolated compounds were screened for their α-glucosidase enzyme inhibition and antiglycation potential. Key findings: It is shown in the results that two compounds (Kaempferol and 8-Methoxyeriodictyol) isolated from plant Iris unguicularis and compounds (Arborinone and 5,7-dihydroxy-2′,6-dimethoxyisoflavone) isolated from plant Iris loczyi possess promising activity against α-glucosidase enzyme as compare to acarbose which is used as a standard α-glucosidase inhibitor in this study. A flavanone (2′,5-dihydroxy-6,7-methylenedioxy) isolated from Iris loczyi was explored as most active anti-glycating agent. Significance: α-Glucosidase enzyme is a therapeutic target to treat carbohydrate mediated diseases. In this study various inhibitors of α-glucosidase are identified which might be important for the management of diabetes. Similarly, antiglycation agents may have application for the management of late diabetic complications. [Copyright &y& Elsevier]

A diarylheptanoid, named 3,17-dihydroxy-tricyclo[ 12.3.1.12,6]nonadeca-1(18),2,4,6(19),14,16-hexaen-9,11-dione, was newly isolated from the branch wood of Alnus sieboldiana, together with two known diarylheptanoids. The chemical struc-ture of this compound was assigned on the basis of the NMR and MS data, information obtained though 1D- and 2D-NMR analyses. These three diarylheptanoids were found to significantly inhibit the activity of α-glucosidase. [ABSTRACT FROM AUTHOR]

A new triterpene glycoside, 3-O-[(α-L-rhamnopyranosyl)(1→2)]-[β-Dglucuronopyranosyl- 6-O-methyl ester]-olean-12-ene-28-olic acid (1) and a new indole alkaloid, 5-methoxy-2-oxoindolin-3-acetic acid methyl ester (5) were isolated from the leaves of Acanthopanax senticosus Harms along with six known compounds. The structures of the new compounds were determined by means of 2D-NMR experiments and chemical methods. All the isolated compounds were evaluated for their glycosidase inhibition activities and compound 6 showed significant α-glucosidase inhibition activity. [ABSTRACT FROM AUTHOR]

• Effects of extrusion on the phenolic compounds of hempseed hull were studied. • Extrusion led to a higher total phenolic content and antioxidant properties. • Extrusion has potential to improve anti-diabetic and neurodegeneration activities. • 26 Hydroxycinnamic acid amides and lignanamides were tentatively identified. • The impact of varying moisture content and screw speed on phenolics was explored. The impact of extrusion at different barrel temperature and screw speed on the hempseed hull was investigated. The extrusion treatments showed significant (p < 0.05) increase in total phenolic content, proportion of free phenolic compounds, and DPPH and ABTS radical scavenging activities. At low screw speed (150 rpm), significantly (p < 0.05) higher α -glucosidase and acetylcholinesterase inhibition activities were observed in the extruded samples. The full factorial model revealed a significant interaction between extrusion parameters on total phenolic/flavonoid content and antioxidant activities for free fraction, and α -glucosidase and acetylcholinesterase inhibition for whole fraction. A total of 26 phenylpropionamides, including hydroxycinnamic acid amides and lignanamides, were identified by HPLC-ESI-QTOF-MS/MS. HPLC-DAD analysis showed a 25–78% increase in total phenylpropionamide content in hempseed hull after extrusion. Pearson's correlation displayed significant (p < 0.05) positive correlation of N - trans -caffeoyltyramine, the most abundant phenylpropionamide, with all biological activities (r = 0.832–0.940). [ABSTRACT FROM AUTHOR]

Salak (Salacca zalacca) is well-known as snake fruit and it is immensely studied for its antioxidative and antidiabetic active metabolites throughout the southeast Asian countries. However, there are many remaining unidentified metabolites due to very low abundance and natural variation, which need to be further explored. Nowadays mass spectrometry (MS/MS) facilitates the tentative identification of unknown compounds in the crude herbal extracts. This study described the metabolite profiling of hydroalcoholic extracts of S. zalacca analysed by LC-QTOF-MS/MS. The 60% ethanolic extract exhibited the highest α-glucosidase inhibition and ferric reducing antioxidant power activities with IC 50 of 15.94 µg/mL and 78.13 μg AAE/g, respectively. Multivariate data analysis (MVDA) by an orthogonal partial least-squares (OPLS) algorithm was conducted to correlate the α-glucosidase inhibition activity with the LC- QTOF-MS data. A total of 4 compounds were reported for first time in this fruit and identified based on the molecular mass and fragment ions. LC-QTOF-MS analysis indicated the presence of carexane I, 5-phenoxytetrazol-1-yl)-2,3,5,6-hexahydrofurofuran-3-ethylurea, 3-acetylphenoxy)-N-[(2)-1-amino-4-methyl-1-oxopentan-2-yl]-4,5-dihydroxycyclohexene-1-carboxamide and Ethyl 4-[5-methyl-2-oxo-1′,2′,5′,6′,7′,7′a-hexahydro-1H-spiro[indole-3,3′-pyrrolizine]-2′-ylamido] benzoate. Molecular docking of those compounds with the α–glucosidase enzyme was performed to confirm their antidiabetic potential. These bioactive compounds could be suggested as α-glucosidase inhibitors and functional food additives. [ABSTRACT FROM AUTHOR]

• New pyrazole-triazolopyrimidines were designed, synthesized and well characterized. • The compound 4j confirmed by the SCXRD. • a-glucosidase inhibition activity evaluated and 4h , 4f and 4l identified as potent acitve compounds. • SAR studies and molecular docking studies were carried out for all the compounds. • 4h , 4f and 4l exhibited good binding interactions and drug-likeness properties, which could be promising hits for anti-diabetic The aim of the present study is to design and synthesis of new pyrazole-triazolopyrimidine hybrids as potent α-glucosidase inhibitors. The target compounds 4a-n were synthesized by one-pot multicomponent approach with good yields and were characterized by various spectroscopic techniques and finally by single crystal X-ray diffraction method (4j). All the newly-synthesized derivatives have been screened for their α-glucosidase enzyme inhibition activity and acarbose taken as a standard drug. Among all the tested compounds, 4h has displayed excellent α-glucosidase enzyme inhibition activity with IC 50 value 12.45 μM to the standard drug acarbose (IC 50 : 12.68 μM). Similarly, the compounds 4f and 4l have exhibited potent activity with IC 50 values 14.47 μM and 17.27 μM respectively. Structure-activity relationship (SAR) studies of all the title compounds were established. The mode of binding interactions between the α-glucosidase enzyme and the compounds were studied. The drug-likeness properties (Lipinski parameters and in silico ADME properties) have predicted for the target compounds. The α-glucosidase inhibition, molecular docking and drug-likeness properties of the compounds 4h , 4f and 4l were suggested that these are promising hits for anti-diabetic activity. [ABSTRACT FROM AUTHOR]

Six new phragmalin limonoids, named moluccensin Z1 (1), moluccensin Z2 (2), carapanolide Y (3), tabulalin N (4), chukvelutilide A1 (5), and velutinasin J (6), as well as two known compounds, chukvelutilide A (7) and velutinasin D (8) were isolated from the stems of Chukrasia tabularis A. Juss. The structures of the new compounds 1–6 were confirmed by spectroscopic methods, including IR and HRESIMS, as well as 1D and 2D NMR, and by comparisons with the data of known analogues. All compounds were tested for α-glucosidase and acetylcholinesterase inhibitory activities. However, none of the compounds was active against α-glucosidase and acetylcholinesterase in vitro. [ABSTRACT FROM AUTHOR]

There are both soluble and insoluble-bound forms of phenolics in tea-leaf products. In order to increase total soluble phenolics contents, guava leaves tea (GLT) was first fermented with Monascus anka and Saccharomyces cerevisiae, and then hydrolyzed with complex enzymes. The changes in phenolics profiles, antioxidant activities and inhibitory effect on α-glucosidase in processed GLT were investigated. Compared with the un-fermented GLT, fermentation and complex enzymatic processing (FE) significantly increased the total phenolics, total flavonoids, quercetin and kaempferol contents by 2.1, 2.0, 13.0 and 6.8 times, respectively. After the FE, a major proportion of phenolics existed in the soluble form. Quercetin was released in the highest amount among different phenolics. In addition, soluble phenolic extracts from GLT following FE exhibited a highest antioxidant activity and inhibitory effect on α-glucosidase. The paper suggested an improved method for processing GLT into high-value products rich in phenolics and flavonoids aglycones with enhanced health benefits., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

The aim of this study was to compare the quality and physicochemical characteristics of blue-shelled eggs (BE) and conventional eggs (CE). Proximate composition, quality, pH value, shell color, collagen content, fatty acid composition, total cholesterol, α-glucosidase inhibition activity, and antioxidation activity were determined. The proximate composition, general qualities, and pH values of CE and BE showed no significant differences, except in moisture composition, weight, and shell thickness. Moisture content and weight of BE were significantly lower than those of CE. However, shell thickness and weight of BE were higher than those of CE ( p <0.05). Lightness of BE was significantly higher than that of CE (85.20 vs. 58.80), while redness ( a *) and yellowness ( b *) of BE were lower than those of CE ( a *: -4.75 vs. 14.20; b *: 10.45 vs. 30.63). The fatty acid [C18:1n7 (cis-vaccenic acid) and C18:3n6 (gamma-linolenic acid)] contents of BE were significantly higher than those of CE. The total cholesterol contents of BE and CE were similar. DPPH radical scavenging activity of BE was significantly higher than that of CE (40.78 vs. 35.35). Interestingly, α-glucosidase inhibition activity of whole egg and egg yolk in BE (19.27 and 36.06) was significantly higher than that of whole egg and egg yolk in CE (13.95 and 32.46). This result indicated that BE could potentially be used as a functional food material. Further studies are required to evaluate the specific compounds that affect functional activity.