Phytochemical Screening and Antidiabetic Activity of Aqueous Extract of Evolvulus Alsinoides Leaves: An In Vitro and In Silico Study

Background

Nowadays, diabetes mellitus has become common worldwide due to changes in lifestyle, sedentary life, alterations in food habits, and other genetic and environmental factors. It is necessary to create awareness about the growing pandemic.

Aim

To evaluate the antidiabetic potential of Evolvulus alsinoides.

Methods

In vitro α-amylase inhibition and α-glucosidase inhibition activity. Molecular docking analysis.

Results

The plant is rich in naturally occurring phytocompound. The results of the study showed that E. alsinoides has the potential to inhibit the activity of alpha-amylase and alpha-glucosidase. Moreover, this result was validated using in silico molecular docking studies that showed a good binding affinity of one of the major phytocompound, caffeic acid, with molecules in the insulin signaling cascade.

Conclusion

E. alsinoides has a potent antidiabetic activity and can be further employed in animal and human studies.

Nanoemulsions (O/W) prepared from essential oil extracted from Melaleuca alternifolia: synthesis, characterization, stability and evaluation of anticancerous, anti-oxidant, anti-inflammatory and antidiabetic activities

Essential oil from Melaleuca alternifolia (also known as Tea tree essential oil, TTO) is used as traditional medicine and used as therapeutic in medicine, food and cosmetic sectors. However, this oil is highly unstable, volatile and prone to oxidation which limits its practical use. The objective of this study was synthesis of tea tree oil based O/W (oil/water) nanoemulsions (tea tree essential oil nanoemulsions, TNE) and evaluation of its biological potential. Physiological characterization was carried out using UV, fluorescent, and FT-IR techniques. Various biological activities such as anticancerous, antidiabetic and anti-inflammatory were also estimated. Pharmacokinetics study on TNE was carried out. Encapsulation efficiency of nanoemulsions was found to be 83%. Nanoemulsions were spherical in shape with globule size 308 nm, zeta potential -9.42 and polydispersity index was 0.31. Nanoemulsions were stable even after 50 days of storage at different temperatures. Anti-oxidant potential of TNE was conducted by various assays and IC50 were: Nitric oxide radical scavenging activity:225.1, DPPH radical scavenging activity:30.66, Iron chelating assay:38.73, and Iron reducing assay:39.36. Notable anticancer activity was observed with the percent cell viability of HeLa cells after treatment with 1, 2 and 5 µl of TNE was 82%, 41% and 24%, respectively. Antidiabetic study revealed that TNE inhibited -amylase in a dose-dependent manner, with 88% inhibition at its higher volume of 250 µl. Drug kinetic study revealed that nanoemulsions exhibited first-order model. Based on this, the possible role of M. alternifolia oil-based nanoemulsions in cosmetic, food, and pharma sectors has been discussed.

Green synthesis of silver nanoparticles from plant Fagonia cretica and evaluating its anti-diabetic activity through indepth in-vitro and in-vivo analysis

One of the most widespread metabolic diseases, Type-2 Diabetes Mellitus (T2DM) is defined by high blood sugar levels brought on by decreased insulin secretion, reduced insulin action, or both. Due to its cost-effectiveness and eco-friendliness, plant-mediated green synthesis of nanomaterials has become more and more popular. The aim of the study is to synthesize AgNPs, their characterizations and further in-vitro and in-vivo studies. Several methods were used to morphologically characterise the AgNPs. The AgNPs were crystalline, spherical, and clustered, with sizes ranging from 20 to 50 nm. AgNPs were found to contain various functional groups using Fourier transform infrared spectroscopy. This study focuses on the green-synthesis of AgNPs from Fagonia cretica (F. cretica) leaves extract to evaluate their synthesized AgNPs for in-vitro and in-vivo anti-diabetic function. For the in-vivo tests, 20 male Balb/C albino-mice were split up into four different groups. Anti-diabetic in-vivo studies showed significant weight gain and a decrease in all biochemical markers (pancreas panel, liver function panel, renal function panel, and lipid profile) in Streptozotocin (STZ)-induced diabetic mice. In vitro anti-diabetic investigations were also conducted on AgNPs, comprising α-amylase, α-glucosidase inhibitions, and antioxidant assays. AgNPs showed antioxidant activity in both the DPPH and ABTS assays. The research showed that the isolated nanoparticles have powerful antioxidant and enzyme inhibitory properties, especially against the main enzymes involved in T2DM.

Antihyperglycemic potential of the Lavandula stoechas aqueous extract via inhibition of digestive enzymes and reduction of intestinal glucose absorption

BACKGROUND

Diabetes mellitus is a widespread metabolic disorder affecting global populations. Lavandula stoechas from Moroccan traditional medicine is used for its potential anti-diabetic effects.

OBJECTIVE

This study aims to evaluate the antihyperglycemic impact of the aqueous extract of L. stoechas (AqLs) and explore its mechanisms.

METHODS

The study employed a glucose tolerance test (OGTT) on normal and diabetic Wistar rats, administering AqLs at 150 mg/kg. In vitro, AqLs was tested against α-glucosidase and α-amylase activities, confirmed in vivo using normal and Allx-diabetic rats. The extract's impact on intestinal d-glucose absorption was assessed using the jejunum segment perfusion technique at 250 mg/kg in situ. Albino mice were used to assess toxicity.

RESULTS

AqLs significantly reduced postprandial hyperglycemia (P < 0.001) due to glucose overload. It inhibited pancreatic α-amylase (IC50: 0.485 mg/mL) and intestinal α-glucosidase (IC50: 168 µg/mL) in vitro. Oral AqLs at 150 mg/kg reduced hyperglycemia induced by sucrose and starch in normal and diabetic rats. It also lowered (P < 0.001) intestinal glucose absorption in situ at 250 mg/kg. Oral acute toxicity tests on Albino mice indicated no adverse effects at different doses.

CONCLUSION

to summarize, L. stoechas has evident antihyperglycemic effects attributed to inhibiting intestinal glucose absorption and key monosaccharide digestion enzymes like α-amylase and α-glucosidase.

Functional and Bioactive Properties of Wheat Protein Fractions: Impact of Digestive Enzymes on Antioxidant, α-Amylase, and Angiotensin-Converting Enzyme Inhibition Potential

This research aimed to determine the biofunctional properties of wheat flour (WF) protein fractions and modifications to the antioxidant, anti-α-amylase and anti-angiotensin-I converting enzyme (ACE) activities induced by the action of digestive endopeptidases in vitro. A molecular characterization of the most abundant protein fractions, i.e., albumins, glutelins-1, glutelins-2 and prolamins, showed that low- and high-MW polypeptides rich in cysteine, glutamic acid and leucine were present in albumins and glutelins, whereas low-MW subunits with a high proportion of polar amino acids prevailed in prolamins. Prolamins exhibited the second-highest water holding capacity (54%) after WF (84%), while albumins provided superior foam stability (76%). Prolamins, glutenins-1 and globulins demonstrated the highest antioxidant activity (up to 95%, 68% and 59%, respectively) both before and after hydrolysis with pepsin (P-H) or trypsin-chymotrypsin (TC-H). Prolamins, globulins and WF strongly inhibited α-amylase (>90%) before and after TC-H, and before P-H (55-71%). Moreover, P-H significantly increased α-amylase inhibition by albumins from 53 to 74%. The fractions with strong ACE inhibitory activity (70-89%) included prolamins and globulins after TC-H or P-H, as well as globulins before TC-H and WF before P-H. This novel evidence indicates that WF protein fractions and their peptide-enriched P and TC hydrolysates are excellent sources of multifunctional bioactives with antioxidant, antihyperglycemic and antihypertensive potential.

In vitro antidiabetic, antioxidant, antimicrobial, and cytotoxic activity of Murraya koenigii leaf extract intercedes ZnO nanoparticles

Nanotechnology is an emerging field with tremendous potential and usage of medicinal plants and green preparation of nanoparticles (NPs) is one of the widely explored areas. These have been shown to be effective against different biological activities such as diabetes mellitus, cancer, antioxidant, antimicrobial, etc. The current studies focus on the green synthesis of zinc NPs (ZnO NPs) from aqueous leaf extract of Murraya koenigii (MK). The synthesized Murraya koeingii zinc oxide NPs (MK ZnO NPs) were characterized using UV-visible spectroscopy, dynamic light scattering (DLS), Fourier transform infrared (FTIR) spectroscopy, field emission scanning electron microscopy (FESEM), energy-dispersive spectrum (EDS) and cyclic voltammetry (CV). The synthesized MK ZnO NPs were evaluated for their in vitro antidiabetic, antioxidant, antimicrobial, and cytotoxic activity. They demonstrated significant antidiabetic and cytotoxic activity, as well as moderate free-radical scavenging and antibacterial activity.

In-depth in-vitro and in-vivo anti-diabetic evaluations of Fagonia cretica mediated biosynthesized selenium nanoparticles

Therapeutic moieties derived from medicinal plants as well as plants-based ecofriendly processes for producing selenium nanoparticles have shown great promise in the management of type 2 diabetes mellitus (T2DM). The current study was aimed to assess the anti-diabetic potentials of Fagonia cretica mediated biogenic selenium nanoparticles (FcSeNPs) using in-vitro and in-vivo approaches. The bio-synthesized FcSeNPs were characterized using various techniques including UV-VIS spectrophotometry and FTIR analysis. The in-vitro efficacy of FcSeNPs were assessed against α-glucosidase, α-amylase enzymes as well as the anti-radical studies were performed using DPPH and ABTS free radicals scavenging assays. For in-vivo studies, 20 Male Balb/C albino-mice were randomly divided into 4 groups (n = 5) including normal group, disease group (Diabetic group with no treatment), control group and treatment group (Diabetic group treated with FcSeNPs). Further, biochemistry markers including pancreas, liver, kidney and lipid profile were assessed for all treatment groups. The FcSeNPs exhibited a dose-dependent inhibition against α-amylase and α-glucosidase at 62-1000 µg mL^-1 concentration with IC₅₀ values of 92 and 100 µg mL^-1 respectively. In antioxidant experiments, the FcSeNPs demonstrated significant radicals scavenging effect against DPPH and ABTS radicals. In STZ-induced diabetic mice, a considerable decline in blood glucose level was observed after treatment with FcSeNPs. Anti-hyperglycemic effect of FcSeNPs treated animals were high (105 ± 3.22**) as compared to standard drug (128.6 ± 2.73** mg dL^-1). Biochemical investigations revealed that all biochemical parameters for pancreas, liver function, renal function panel and lipid profile were significantly lowered in FcSeNPs treated animals. Our findings indicate a preliminary multi-target efficacy for FcSeNPs against type-2 diabetes and thus warrant further detailed studies.

Underutilized Plant Cymbopogan martinii Derived Essential Oil Is Excellent Source of Bioactives with Diverse Biological Activities

Cymbopogan martinii, also known as Palmarosa, is an underutilized plant of tropical region. Due to outstanding antioxidant potential it has been used as a part of conventional medicine and beauty product. Regardless of its importance, complete pharmacological and phytochemical studies are still in its early stages. In the current study, Palmarosa essential oil (PRO) was extracted from Cymbopogan martinii and was evaluated for its phytochemicals, antimicrobial and antifungal, anti-inflammatory and anti-diabetic and protection from UV rays. Oil from fresh leaves was extracted and analysed for presence of phytochemicals (Tannin, Flavonoids, and Phenolics). Various antioxidant activities like DPPH (1,1-diphenyl-2-picrylhydrazyl), ABTS (2,2-azinobis-3-ethylbenzothiazoline-6-sulphonic acid), Nitric oxide radical, Hydroxyl radical, iron reducing, iron cheating activity were performed. Antibacterial, anti-inflammatory, Antidiabetic, membrane integrity assay, and UV-absorption assay was also performed. Antifungal activity against "Aspergillosis" and "Mucormycosis" causing fungal strains was also evaluated. High concentration of polyphenolics like Tannin, Flavonoid, phenolics were revealed through phytochemical analysis. GC-FID revealed the presence of Geraniol, major component of Palmarosa oil and other bioactive compound in PRO. PRO showed high anti-inflammatory and anti-diabetic potential and can be used as an Antidiabetic agent due to inhibitory effect on α-amylase activity. Further study revealed that PRO inhibits α-amylase in competitive manner. Hence from the results obtained it is confirmed that the PRO possesses considerable amount of bioactive compounds and can be used in pharmaceutical, food and cosmetic industries.

Composition of Powdered Freeze-Dried Orange Juice Co-Product as Related to Glucose Absorption In Vitro

The reuse of food by-products is crucial for the well-being of the planet. Considering the high content of nutrients and other bioactive compounds in many of them, investigating their suitability for use as human food ingredients is an interesting challenge. In this study, in addition to the proximate composition, phenol content and antioxidant activity (AOA = 3.2 mmol Trolox equivalent (TE)/100 g, db) of orange juice powder by-product (CoP), different in vitro properties related to carbohydrate metabolism have been characterised. Specifically, the glycaemic index (GI), the glycaemic load (GL), the glucose dialysis retardation index (GDRI = 13.6%), the glucose adsorption capacity (GAC = 22.5 mM) and the inhibition capacity of α-amylase (α-A = 46.9%) and α-glucosidase (α-G = 93.3%) of powdered orange juice waste have been determined and related to fibre and phenolics composition. Taking advantage of the high fibre content of the by-product (36.67%), its GL was calculated for a CoP dose that allows labelling the food to which it is added as a source of fibre. The low GI value (24.4%) and the low GL (0.918 g available carbohydrates per serving) allowed us to conclude that the product studied could be an interesting opportunity for the food industry to offer it as a healthy food ingredient to be included in the diet, especially for those suffering from type 2 diabetes mellitus. Of the total phenolic compounds (TP = 509 mg equivalent of gallic acid (GAE)/100 g, db), 68% were found in free fraction (FP), and their contribution to the total AOA was 40.6%, while this was 54.9% for the 32% of phenols bound to plant tissues (BP).

Antidiabetic and Anticancer Potentials of Mangifera indica L. from Different Geographical Origins

Mango fruit is well known for its nutritional and health benefits due to the presence of a plethora of phytochemical classes. The quality of mango fruit and its biological activities may change depending upon the variation in geographical factors. For the first time, this study comprehensively screened the biological activities of all four parts of the mango fruit from twelve different origins. Various cell lines (MCF7, HCT116, HepG2, MRC5) were used to screen the extracts for their cytotoxicity, glucose uptake, glutathione peroxidase activity, and α-amylase inhibition. MTT assays were carried out to calculate the IC50 values for the most effective extracts. The seed part from Kenya and Sri Lanka origins exhibited an IC50 value of 14.44 ± 3.61 (HCT116) and 17.19 ± 1.60 (MCF7). The seed part for Yemen Badami (119 ± 0.08) and epicarp part of Thailand (119 ± 0.11) mango fruit showed a significant increase in glucose utilization (50 μg/mL) as compared to the standard drug metformin (123 ± 0.07). The seed extracts of Yemen Taimoor seed (0.46 ± 0.05) and Yemen Badami (0.62 ± 0.13) produced a significant reduction in GPx activity (50 μg/mL) compared to the control cells (100 μg/mL). For α-amylase inhibition, the lowest IC50 value was observed for the endocarp part of Yemen Kalabathoor (108.8 ± 0.70 μg/mL). PCA, ANOVA, and Pearson’s statistical models revealed a significant correlation for the fruit part vs. biological activities, and seed part vs. cytotoxicity and α-amylase activity (p = 0.05). The seed of mango fruit exhibited significant biological activities; hence, further in-depth metabolomic and in vivo studies are essential to effectively utilize the seed part for the treatment of various diseases.

Biological Screening of Glycyrrhiza glabra L. from Different Origins for Antidiabetic and Anticancer Activity

BACKGROUND

Geographical variation may affect the phytochemistry as well as the biological activities of Glycyrrhiza glabra (licorice) root. Herein, a series of biological activities were performed to evaluate the impact of geographical origin on the biological potential of eight different licorice samples.

METHODOLOGY

Cell culture studies were performed for cytotoxicity (MCF7, HCT116, HepG2, and MRC5), glucose uptake assay (HepG2), and glutathione peroxidase activity (HepG2), whereas α-amylase inhibition activity was tested for antidiabetic potential.

RESULTS

The Indian sample was observed to be more cytotoxic against MCF7 (22%) and HCT116 (43%) with an IC₅₀ value of 56.10 (±2.38) μg/mL against the MCF7 cell line. The glucose uptake was seen with a mean value of 96 (±2.82) and a range of 92-101%. For glutathione peroxidase activity (GPx), the Syrian (0.31 ± 0.11) and Pakistani samples (0.21 ± 0.08) revealed a significant activity, whereas the Palestinian (70 ± 0.09) and Indian samples (68±0.06) effectively inhibited the α-amylase activity, with the lowest IC₅₀ value (67.11 ± 0.97) μg/mL for the Palestinian sample. The statistical models of PCA (principal component analysis) and K-mean cluster analysis were performed to correlate the geographical origin, extract yield, and biological activities for the eight licorice samples of different origins.

CONCLUSION

The licorice samples exhibited significant cytotoxic, GPx, and α-amylase inhibitory activity. The samples with higher extract yield showed more potential in these biological activities.

Synthesis, Characterization, and Biological Evaluation of Tetrahydropyrimidines: Dual-Activity and Mechanism of Action

In this paper, the synthesis, characterization, and biological evaluation of the novel tetrahydropyrimidines-THPMs are described. THPMs are well-known for wide pharmacological activities such as antimicrobial, anticancer, antiviral, etc. This research includes obtained results of in vitro antimicrobial, anticancer, and α-glucosidase inhibitory activities of the eleven novel THPMs. An antibiotic assessment was done against five bacteria (two Gram-positive and three Gram-negative) and five fungi by determining the minimal inhibitory concentration (MIC), using the broth tube dilution method. The most active antibacterial compounds were 4a, 4b, and 4d, while the best antifungal activity was shown by 4e, 4f, and 4k. The lowest MIC value (0.20 mg/mL) was measured for 4e, 4f, and 4k against the Trichophyton mentagrophytes. Moreover, examining the α-glucosidase inhibitory activity revealed the compound 4g as the one with the best activity. The cytotoxic activity was performed on the tumor cell lines (HeLa, K562, and MDA-MB-231) and normal cells (MRC-5). The best antitumor activity was shown by compounds 4b and 4k against HeLa cell lines. The influence on cell cycle and mechanism of action of the most active compounds were examined too. Compound 4b had good antibacterial and anticancer activities, while 4k showed promising antifungal and anticancer activities.

Correlating the charge transfer efficiency of metallic sulfa-isatins to design efficient NLO materials with better drug designs

The present study presents synthesis, characterization and first principle studies on metal chelates, (1-12), of sulfonamide-isatin reacted ligands (S¹-S³). All the products were evaluated by various physical and spectral (UV, IR, NMR, MS) means. The octahedral geometry for Co⁺², Ni⁺² and Zn⁺², while square planner geometry for Cu⁺² chelates were confirmed by their spectroscopic and magnetic data. Their physical chemistry investigation show the ability of aromatic rings to stabilize sulfonamide rings across NH-π interactions at their optimized geometries. The nonlinear optical response for all the compounds disclosed that the z-axis has the most contributions. An efficient electron injection and hole studies for Au and Al electrodes having the energies of - 0.1-3.1 and 0.0-11.8 eV respectively were noted. Their bioactive character was shown by global reactivity calculated from FMO energy gaps. The enzyme inhibitory results were found to be 45-61% and IC₅₀ = 102-122 µL, for compound (4), (10), (8), (5) and (12) against the amylase, protease, acetylcholinesterase (AChE), and butyrylcholinesterase (BChE) respectively The antibacterial findings showed significant action having 11-17 mm for (2), (7) and (10) for bacterial species, Escherichia coli and Micrococcus luteus. The DPPH and ferric reducing power assay was used to evaluate the antioxidant capacity with 49.0 ± 0.09-66.2 ± 0.08% and IC₅₀ = 102.3-122.4 µL range. In comparison to ligands, the results showed that all metal chelates had higher bioactivity. The chelation was the primary cause of their increased bioactivity. These findings suggested that such metal-based compounds might be used as antimicrobial, and antioxidant options in future to cope drug resistance.

Inhibition of α-Amylase and α-Glucosidase of Anthocyanin Isolated from Berberis integerrima Bunge Fruits: A Model of Antidiabetic Compounds

Anthocyanins are components of the flavonoid group with different properties, such as antidiabetic properties. This study aimed to isolate anthocyanin from Berberis integerrima Bunge fruits and evaluate α-amylase and α-glucosidase inhibition by this mentioned anthocyanin. The anthocyanin of Berberis integerrima fruit was isolated using column chromatography, and the antidiabetic properties of the anthocyanin were determined by the levels of α-amylase and α-glucosidase inhibition. Km and Vmax were also evaluated using the GraphPad Prism 7. The results of this study showed that the anthocyanin content of the fruit extract was 14.36 ± 0.33 mg/g, and following purification, this amount increased to 34.51 ± 0.42 mg/g. The highest of α-glucosidase inhibition was observed in the purified anthocyanin with IC₅₀ = 0.71 ± 0.085 mg/ml, compared to acarbose as the baseline with IC₅₀ = 8.8 ± 0.14 mg/ml, p < 0.0001. Purified anthocyanin of the mentioned fruit with IC₅₀ = 1.14 ± 0.003 mg/ml had the greatest α-amylase inhibition, which was similar to acarbose as the standard with IC₅₀ = 1 ± 0.085 mg/ml, p < 0.05. The inhibition of α-glucosidase and α-amylase by purified anthocyanin showed uncompetitive inhibition, and the enzyme inhibition by unpurified anthocyanin showed mixed inhibition. The obtained findings showed that Berberis integerrima fruit can be mentioned as a source of anthocyanin with antidiabetic properties.

Nanoemulsions (O/W) containing Cymbopogon pendulus essential oil: development, characterization, stability study, and evaluation of in vitro anti-bacterial, anti-inflammatory, anti-diabetic activities

Essential oil from Cymbopogon pendulus is immensely useful in various sectors like food, pharmaceutical, and cosmetic industries. Since this oil is hydrophobic, unstable, and volatile, hence encapsulation by using nanoemulsions technology is the best way to protect it. This study reports biosynthesis of O/W (oil/water) nanoemulsions based on essential oil from Cymbopogon pendulus and analysis of its biological activities. O/W nanoemulsions were prepared by using tween 20/80, sodium dodecyl sulphate as surfactants, and ethanol as co-surfactants. Fingerprinting of nanoemulsions using UV, fluorescent, and FT-IR was studied along with other parameters like pH and conductivity. Biological activities like antibacterial, anti-inflammatory, and anti-diabetic activities and drug release pharmokinetics were evaluated. Ethanol containing nanoemulsions was noticeably smaller than other nanoemulsions. Encapsulation efficiency of nanoemulsions was in the range from 41 to 60%. Nanoemulsions were spherical in shape and stable even after 50 days of storage. Appreciable biological activities like anti-bacterial, anti-inflammatory, and anti-diabetic activities were detected. Drug kinetic study revealed that nanoemulsions exhibited Korsmeyer-Peppas model. Based on this, the possible role of lemon grass oil-based nanoemulsions in cosmetic, food, and pharma sectors has been discussed.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12668-022-00964-4.

Phytochemical Analysis, α-Glucosidase and Amylase Inhibitory, and Molecular Docking Studies on Persicaria hydropiper L. Leaves Essential Oils

Objective

Medicinal plants and essentials oils are well known for diverse biological activities including antidiabetic potential. This study was designed to isolate essential oils from the leaves of Persicaria hydropiper L. (P. hydropiper), perform its phytochemical analysis, and explore its in vitro antidiabetic effects.

Materials and Methods

P. hydropiper leaves essential oils (Ph.Los) were extracted using a hydrodistillation apparatus and were subjected to phytochemical analysis using the gas chromatography mass spectrometry (GC-MS) technique. Ph.Lo was tested against two vital enzymes including α-glucosidase and α-amylase which are important targets in type-2 diabetes. The identified compounds were tested using in silico approaches for their binding affinities against the enzyme targets using MOE-Dock software.

Results

GC-MS analysis revealed the presence of 141 compounds among which dihydro-alpha-ionone, cis-geranylacetone, α-bulnesene, nerolidol, β-caryophyllene epoxide, and decahydronaphthalene were the most abundant compounds. Ph.Lo exhibited considerable inhibitory potential against α-glucosidase enzyme with 70% inhibition at 1000 μg mL⁻¹ which was the highest tested concentration. The inhibitory activity of positive control acarbose was 77.30 ± 0.61% at the same tested concentration. Ph.Lo and acarbose exhibited IC₅₀ of 170 and 18 µg mL⁻¹ correspondingly. Furthermore, dose-dependent inhibitions were observed for Ph.Lo against α-amylase enzyme with an IC₅₀ of 890 μg mL⁻¹. The top-ranked docking conformation was observed for β-caryophyllene epoxide with a docking score of -8.3182 against α-glucosidase, and it has established seven hydrogen bonds and one H-pi interaction at the active site residues (Phe 177, Glu 276, Arg 312, Asp 349, Gln 350, Asp 408, and Arg 439). Majority of the identified compounds fit well in the binding pocket of Tyr 62, Asp 197, Glu 233, Asp 300, His 305, and Ala 307 active residues of α-amylase. β-Caryophyllene epoxide was found to be the most active inhibitor with a docking score of -8.3050 and formed five hydrogen bonds at the active site residues of α-amylase. Asp 197, Glu 233, and Asp 300 active residues were observed to be making polar interactions with the ligand.

Conclusions

The current study revealed that Ph.Lo is rich in bioactive metabolites which might contribute to its enzyme inhibitory potential. Inhibition of these enzymes is the key target in reducing postprandial hyperglycemia. However, further detailed in vivo studies are required for their biological and therapeutic activities.

An investigationof the inhibitory effects of dichloromethane and methanol extracts of Salvia macilenta, Salvia officinalis, Salvia santolinifola and Salvia mirzayanii on diabetes marker enzymes, an approach for the treatment diabetes

Background

Diabetes mellitus is a type of metabolic disease characterized by elevated blood sugar. The main strategy for its treatment is to inhibit carbohydrate-hydrolyzing enzymes, including α-amylase and α-glucosidase. The aim of the present study was to evaluate the efficacy of Salvia extracts in inhibiting diabetes marker enzymes.

Materials and methods

This experimental study was performed in vitro. The studied plants included Salvia mirzayanii, Salvia macilenta, Salvia officinalis and Salvia santolinifola and inhibitory effects of their methanolic and dichloromethane extracts were investigated. After calculating the percentage of α-amylase inhibition and IC50 of the extracts, Km and Vmax were also determined using prism7.Statistical analysis was performed employing with Graph Pad instat3 software.

Results

The results here in revealed that methanol extracts of Salvia santolinifola (with IC50 = 54.72 ± 9.6 μg / ml) and Salvia officinalis with (IC50 = 54.87 ± 5.7 μg / ml) and dichloromethane extract of Salvia officinalis with (IC50 = 71.20 ± 14.3 μg / ml) had the greatest inhibitory effect on α-amylase comparing to acarbose with (IC50 = 42.94 ± 3.8 μg / ml) as a standard. Tukey test results showed that there is a significant difference between IC50 of acarbose comparing to methanol extract of Salvia mirzayanii and dichloromethane extracts of Salvia mirzayanii and Salvia santolinifola with P value ˂0.001 in α-amylase inhibition.

Conclusion

The extracts had significant inhibitory effects on α-amylase inhibition. Among the extracts of the studied species, methanol extract of Salvia santolinifola demonstrated the greatest inhibitory effect on α-amylase.

HPLC-DAD phenolics analysis, α-glucosidase, α-amylase inhibitory, molecular docking and nutritional profiles of Persicaria hydropiper L

BACKGROUND

Natural phenolic compounds and Phenolics-rich medicinal plants are also of great interest in the management of diabetes. The current study was aimed to analyze phenolics in P. hydropiepr L extracts via HPLC-DAD analysis and assess their anti-diabetic potentials using in-vitro and in-silico approaches.

METHODS

Plant crude methanolic extract (Ph.Cme) was evaluated for the presence of phenolic compounds using HPLC-DAD analysis. Subsequently, samples including crude (Ph.Cr), hexane (Ph.Hex), chloroform (Ph.Chf), ethyl acetate (Ph.EtAc), butanol (Ph.Bt), aqueous (Ph.Aq) and saponins (Ph.Sp) were tested for α-glucsidase and α-amylase inhibitory potentials and identified compounds were docked against these target enzymes using Molecular Operating Environment (MOE) software. Fractions were also analyzed for the nutritional contents and acute toxicity was performed in animals.

RESULTS

In HPLC-DAD analysis of Ph.Cme, 24 compounds were indentfied and quantified. Among these, Kaemferol-3-(p-coumaroyl-diglucoside)-7-glucoside (275.4 mg g- 1), p-Coumaroylhexose-4-hexoside (96.5 mg g- 1), Quercetin-3-glucoronide (76.0 mg g- 1), 4-Caffeoylquinic acid (58.1 mg g- 1), Quercetin (57.9 mg g- 1), 5,7,3'-Trihydroxy-3,6,4',5'-tetramethoxyflavone (55.5 mg g- 1), 5-Feruloylquinic acid (45.8 mg g- 1), Cyanidin-3-glucoside (26.8 mg g- 1), Delphinidin-3-glucoside (24 mg g- 1), Quercetin-3-hexoside (20.7 mg g- 1) were highly abundant compounds. In α-glucosidase inhibition assay, Ph.Sp were most effective with IC50 value of 100 μg mL-1. Likewise in α-amylase inhibition assay, Ph.Chf, Ph.Sp and Ph.Cme were most potent fractions displayed IC50 values of 90, 100 and 200 μg mL-1 respectively. Docking with the α-glucosidase enzyme revealed top ranked conformations for majority of the compounds with Kaemferol-3-(p-coumaroyl-diglucoside)-7-glucoside as the most active compound with docking score of - 19.80899, forming 14 hydrogen bonds, two pi-H and two pi-pi linkages with the Tyr 71, Phe 158, Phe 177, Gln 181, Arg 212, Asp 214, Glu 276, Phe 300, Val 303, Tyr 344, Asp 349, Gln 350, Arg 439, and Asp 408 residues of the enzyme. Likewise, docking with α-amylase revealed that most of the compounds are well accommodated in the active site residues (Trp 59, Tyr 62, Thr 163, Leu 165, Arg 195, Asp 197, Glu 240, Asp 300, His 305, Asp 356) of the enzyme and Cyanidin-3-rutinoside displayed most active compound with docking score of - 15.03757.

CONCLUSIONS

Phytochemical studies revealed the presence of highly valuable phenolic compounds, which might be responsible for the anti-diabetic potentials of the plant samples.

Impact of solid-state fermentation on factors and mechanisms influencing the bioactive compounds of grains and processing by-products

Cereal and legume grains and their processing by-products are rich sources of bioactives such as phenolics with considerable health potential, but these bioactives suffer from low bioaccessibility and bioavailability, resulting in limited use. Several studies have demonstrated that solid-state fermentation (SSF) with food-grade microorganisms is effective in releasing bound phenolic compounds in cereal and legume products. In this review, we discuss the effect of SSF on cereal and legume grains and their by-products by examining the role of specific microorganisms, their hydrolytic enzymes, fermentability of agri-food substrates, and the potential health benefits of SSF-enhanced bioactive compounds. SSF with fungi (Aspergillus spp. and Rhizopus spp.), bacteria (Bacillus subtilis and lactic acid bacteria (LAB) spp.) and yeast (Saccharomyces cerevisiae) significantly increased the bioactive phenolics and antioxidant capacities in cereal and legume grains and by-products, mainly through carbohydrate-cleaving enzymes. Increased bioactive phenolic and peptide contents of SSF-bioprocessed cereal and legume grains have been implicated for improved antioxidant, anti-inflammatory, anti-carcinogenic, anti-diabetic, and angiotensin-converting-enzyme (ACE) inhibitory effects in fermented agri-food products, but these remain as preliminary results. Future research should focus on the microbial mechanisms, suitability of substrates, and the physiological health benefits of SSF-treated grains and by-products.

A review of some common African spices with antihypertensive potential

Hypertension is the most common non-communicable disease, with about 1.28 billion hypertensive people worldwide. It is more prevalent in men than women and more common in the elderly. Hereditary, age, obesity, lifestyle, diet, alcohol, and chronic metabolic diseases are the major risk factors of hypertension. Treating hypertension is a complex process as there are several mechanisms responsible for its pathogenesis; hence, a combination of several drugs is used for managing hypertension. Drugs used in managing hypertension are expensive and often come with associated side effects; thus, there is need for alternative means of managing this life-threatening disease. These drugs do not achieve the recommended blood pressure target in most people; more so majority of people with hypertension do not follow the treatment regimen religiously. Some Africans have been reported to become normotensive as a result of dietary consumption of spices. Several spices have been used over the years in Africa to manage hypertension. The aim of this review is to evaluate the ethnomedicinal use, bioactive phytochemical composition, bioactive compounds present, and pharmacological applications of spices commonly used in Africa for managing hypertension. Most of the plants used contained polyphenols, flavonoids, tannins, anthraquinone, flavonoids, cardiac glycosides, and saponins. Dietary supplementation of Xylopia aethiopica and other spices in diet have been proven to significantly reduced plasma angiotensin-I-converting enzyme (ACE) than simvastatin (the reference drug). Toxicological, histological, and hematological evaluation revealed that acute and chronic consumption of most of these spices are safe. Studies have also revealed that some of the spices can be used as alternative therapy alongside usual antihypertensive medications. PRACTICAL IMPLICATION: The prevalent rate of hypertension is on the increase in both the developed and developing countries. People often skip medication due to their busy schedule and anti-hypertensive potential side effects; however, this is not the case with food/spices as most people consumed them daily. Deliberate, right combinations and consistent incorporation of spices with proven anti-hypertensive potential into our diet may be of great benefit in normalizing blood pressure and mitigate other complications on the heart and vital organs.

Using Biological Elicitation to Improve Type 2 Diabetes Targeted Food Quality of Stored Apple

Food quality improvements of fresh fruits targeting both food preservation and human health is essential to advance healthy dietary options and to mitigate imbalanced nutrition-linked non-communicable chronic disease (NCDs) challenges globally. Specifically, protective phenolic bioactives of fruits with dual functional benefits can be harnessed to advance innovations for improving nutritional quality and post-harvest shelf-life of perishable fruits. Based on this rationale the dual functional benefits of plant phenolics were harnessed using novel biological elicitation strategies to modulate phenolic bioactive-linked protective responses in apple during storage in two interrelated studies. Bioprocessed food-grade elicitors [water soluble chitosan oligosaccharide -(COS) and phenolic enriched oregano extracts-(OX)] were targeted as post-harvest dipping treatments (2 &amp; 4 g/ L) and compared with diphenylamine (DPA) (1 &amp; 2 g/L) to enhance phenolic-linked antioxidant and anti-diabetic (type 2 diabetes) relevant properties of Cortland apple during 3 months of storage (4°C). The selection of bio-elicitors and respective doses were based on the foundations of the previous related study, which resulted in reduction of superficial scald of Cortland apple during storage. Apples sampled over 3 months as aqueous and ethanol (12%) extracts of peel and pulp were analyzed separately for total soluble phenolic content, phenolic profile, antioxidant activity, and glucose metabolism relevant α-amylase and α-glucosidase enzyme inhibitory activities using in vitro assay models. Enhanced soluble phenolic content and associated antioxidant activity were observed in ethanol (12%) extracts of apple peel with 4 g/L COS elicitor treatments after 2 and 3 months of storage. High chlorogenic acid and quercetin derivatives were found in peel extracts of Cortland apple, while pulp extracts had high chlorogenic and gallic acids. Additionally, high α-glucosidase enzyme inhibitory activity, which is relevant for managing post-prandial hyperglycemia of type 2 diabetes was also observed in bio-elicited apple peel and pulp extracts. Therefore, results of these two interrelated studies indicate that bioprocessed food grade elicitor such as OX and COS can be recruited as a novel tool to enhance protective phenolic responses for improving type 2 diabetes targeted food quality and post-harvest storage quality of apple.

Improving Phenolic Bioactive-Linked Functional Qualities of Sweet Potatoes Using Beneficial Lactic Acid Bacteria-Based Biotransformation Strategy

Beneficial lactic acid bacteria (LAB) based fermentation is an effective biotransformation strategy to preserve and improve the human health-supporting functional qualities of plant-based food substrates. In this study, a food grade strain of Lactiplantibacillus plantarum was recruited to improve the retention, stability, and bioavailability of phenolic bioactives to enhance the antioxidant, anti-hyperglycemic, and anti-hypertensive functional qualities of three flesh-colored sweet potato varieties, Murasaki (off-white-fleshed), Evangeline (orange-fleshed), and NIC-413 (purple-fleshed). Liquid (cold water) extracts of the sweet potatoes, which are relevant for food grade applications, were fermented for 72 h at 37 °C. Total soluble phenolic content, phenolic profile, antioxidant, anti-hyperglycemic, and anti-hypertensive benefits relevant functional properties of fermented and unfermented sweet potato extracts were evaluated at 0, 24, 48, and 72 h time points using in vitro assay models. Overall, high total soluble phenolic content and total antioxidant activity were observed at 24 h, retaining this high level even after 72 h of fermentation. Additionally, moderate to high α-amylase, α-glucosidase, and angiotensin-I-converting enzyme inhibitory activities were observed in the fermented sweet potato extracts. The results suggested that LAB-based fermentation is an effective post-harvest processing strategy for a higher retention of phenolic bioactives and concurrently improves the human health protective bioactive functional qualities of sweet potatoes.

Kefir Culture-Mediated Fermentation to Improve Phenolic-Linked Antioxidant, Anti-Hyperglycemic and Human Gut Health Benefits in Sprouted Food Barley

The bioprocessing strategy is an effective approach to improve bioavailability and stability of bioactive compounds for designing functional foods and ingredients. In this study, food barley was bio-transformed to improve functional bioactives by sprouting, coupled with beneficial lactic acid bacteria (LAB)-based fermentation. Dairy Kefir culture with mixed beneficial LAB strains was targeted to ferment aqueous slurries of sprouted hulless food barley flour (unpigmented, purple, and black barley) for 72 h, and modulation of phenolic-linked antioxidant and anti-hyperglycemic functionalities were evaluated using in vitro assay models. The biochemical parameters analyzed were total soluble phenolic (TSP) content, profile of phenolic compounds, total antioxidant activity, and anti-hyperglycemic property-relevant α-amylase and α-glucosidase enzyme inhibitory activities. Furthermore, human gut health benefits of relevant properties of fermented slurries of barley flour were also evaluated based on growth of Kefir culture and subsequent determination of anti-bacterial potential against pathogenic human ulcer causing bacteria Helicobacter pylori. Kefir culture-mediated fermentation of 48-h sprouted barley flours improved the TSP content and associated antioxidant and anti-hyperglycemic functionalities. Additionally, anti-bacterial potential against H. pylori and sustaining active growth of viable LAB cells above the minimum level required for probiotic activity were also observed in fermented food barley flour slurries.

Barks of Three Wild Pyrus Taxa: Phenolic Constituents, Antioxidant Activity, and in Vitro and in Silico Investigations of α-Amylase and α-Glucosidase Inhibition

Dry MeOH extracts of the twig barks of Pyrus communis subsp. pyraster, P. spinosa and their hybrid P.×jordanovii nothosubsp. velenovskyi, collected in wild in Serbia, were analyzed. By LC/MS, the contents of arbutin (99.9-131.0 mg/g), chlorogenic acid (2.2-6.3 mg/g), catechin (1.0-5.3 mg/g) and total dimeric and trimeric procyanidins (42.2-61.3 mg/g), including procyanidin B2 (8.9-17.2 mg/g), were determined. Colorimetrically, high contents of total phenolics (436.2-533.4 mg GAE/g) and tannins (339.4-425.7 mg GAE/g), as well as strong total antioxidant activities (FRAP values 4.5-5.9 mmol Fe²⁺ /g), and DPPH (SC₅₀ =6.6-7.1 μg/ml) and hydroxyl radical (SC₅₀ =447.1-727.7 μg/ml) scavenging abilities were revealed. In vitro, all extracts exhibited notable inhibition of α-amylase (IC₅₀ =310.8-617.7 μg/ml) and particularly strong inhibition of α-glucosidase (IC₅₀ =2.1-3.7 μg/ml). Molecular docking predicted that among identified compounds procyanidin B2 is the best inhibitor of these carbohydrate-digesting enzymes. Obtained results showed that the barks of investigated Pyrus hybrid and its parent taxa have similar composition and bioactivity.

Improving Health Targeted Food Quality of Blackberry: Pear Fruit Synergy Using Lactic Acid Bacterial Fermentation

Blackberry and pear are rich in human health protective phenolic bioactives with high antioxidant activity. These fruits are relevant dietary targets to counter chronic oxidative stress-linked diseases, such as type 2 diabetes (T2D). Due to high perishability, the human health relevant bioactive qualities of such fruits deteriorate during postharvest storage and processing. By improving stability and bioavailability of nutritionally relevant phenolic bioactives during post-harvest stages, effective integration of blackberry and pear as dietary support strategies can be targeted for T2D benefits. Solutions to bioactive quality loss of fruits can be achieved by advancing bioprocessing strategy integrating compatible fruit synergy and beneficial lactic acid bacteria (LAB) based fermentation. This approach was targeted to enhance high levels of phenolic bioactive-linked health quality of blackberry (Rubus spp.) integrated with pear (Pyrus communis) at a ratio of 30:70, which was optimized previously based on potential synergistic effects. The aim of this study was to recruit beneficial LAB such as Lactobacillus helveticus and Bifidobacterium longum to bioprocess previously optimized blackberry: pear synergies to improve phenolic bioactive-linked T2D benefits. Essential health-targeted food quality during bioprocessing was assessed based on total soluble phenolic content, phenolic compound profile, total antioxidant activity, anti-hyperglycemic property relevant α-amylase and α-glucosidase enzyme inhibitory, and anti-hypertensive relevant angiotensin-I-converting enzyme (ACE) inhibitory activities using in vitro assay models. Additionally, potential inhibitory activity of fermented fruit extracts against pathogenic Helicobacter pylori, the common bacterial ulcer pathogen was also investigated. Overall, improvement in the retention and stability of phenolic bioactive content in 30:70 blackberry: pear combination, as well as in 100% juice of both fruit extracts were observed following fermentation. Furthermore, enhanced antioxidant activity, anti-hyperglycemic property relevant α-glucosidase, and anti-hypertensive property relevant ACE enzyme inhibitory activities were also observed in fermented extracts of 30:70 blackberry: pear synergy. Among the substrates only fermentation of 100% blackberry with LAB resulted in inhibitory activity against H. pylori. These results provide the biochemical rationale to develop blackberry: pear fruit synergy and beneficial LAB-based fermentation to improve T2D relevant health benefits while also potentially improving keeping quality.

The Antioxidative Role of Natural Compounds from a Green Coconut Mesocarp Undeniably Contributes to Control Diabetic Complications as Evidenced by the Associated Genes and Biochemical Indexes

The purpose of this study was to look into the effects of green coconut mesocarp juice extract (CMJE) on diabetes-related problems in streptozotocin- (STZ-) induced type 2 diabetes, as well as the antioxidative functions of its natural compounds in regulating the associated genes and biochemical markers. CMJE's antioxidative properties were evaluated by the standard antioxidant assays of 1,1-diphenyl-2-picrylhydrazyl (DPPH), superoxide radical, nitric oxide, and ferrous ions along with the total phenolic and flavonoids content. The α-amylase inhibitory effect was measured by an established method. The antidiabetic effect of CMJE was assayed by fructose-fed STZ-induced diabetic models in albino rats. The obtained results were verified by bioinformatics-based network pharmacological tools: STITCH, STRING, GSEA, and Cytoscape plugin cytoHubba bioinformatics tools. The results showed that GC-MS-characterized compounds from CMJE displayed a very promising antioxidative potential. In an animal model study, CMJE significantly (P < 0.05) decreased blood glucose, serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), creatinine, uric acid, and lipid levels and increased glucose tolerance as well as glucose homeostasis (HOMA-IR and HOMA-b scores). The animal's body weights and relative organ weights were found to be partially restored. Tissue architectures of the pancreas and the kidney were remarkably improved by low doses of CMJE. Compound-protein interactions showed that thymine, catechol, and 5-hydroxymethylfurfural of CMJE interacted with 84 target proteins. Of the top 15 proteins found by Cytoscape 3.6.1, 8, CAT and OGG1 (downregulated) and CASP3, COMT, CYP1B1, DPYD, NQO1, and PTGS1 (upregulated), were dysregulated in diabetes-related kidney disease. The data demonstrate the highly prospective use of CMJE in the regulation of tubulointerstitial tissues of patients with diabetic nephropathy.

Evaluating the Inhibitory Effects of Dichloromethane and Methanol Extracts of Salvia macilenta and Salvia officinalis on the Diabetes Marker Enzyme, Alpha-Glucosidase: An Approach for the Treatment of Diabetes

Background: Diabetes mellitus is believed to be the most serious metabolic disease. One of the treatments for diabetes is to delay glucose uptake by inhibiting carbohydrate-hydrolyzing enzymes. Alpha-glucosidase inhibitors delay glucose uptake. Objectives: The present study was conducted aiming to evaluate the efficacy of Salvia extracts in inhibiting diabetes marker enzymes and their effects on the treatment of diabetes. Methods: This experimental study was performed in vitro. The studied plants included Salvia macilenta and Salvia officinalis. The inhibitory effects of their dichloromethane and methanol extracts were also investigated. After calculating the percentage of inhibition and IC50, Km and Vmax using GraphPad Prism 7 were also calculated. The statistical analysis was performed employing GraphPad Instat 3 software. Results: The results herein showed that the greatest inhibitory effect on alpha-glucosidase belonged to the methanol extract of S. macilenta with IC50 = 8.73 ± 0.26 mg/mL compared to that of acarbose with IC50 = 8.82 ± 0.14 mg/mL as a standard. The IC50 of dichloromethane extract of S. officinalis was 8.95 ± 0.23 mg/mL. Conclusions: The extracts had significant inhibitory effects on alpha-glucosidase. However, methanol extract of S. macilenta and dichloromethane extract of S. officinalis demonstrated the greatest inhibitory effects on alpha-glucosidase compared to acarbose as a standard.

Coumarin-based Scaffold as α-glucosidase Inhibitory Activity: Implication for the Development of Potent Antidiabetic Agents

BACKGROUND

Delaying the absorption of glucose through α-glucosidase enzyme inhibition is one of the therapeutic approaches in the management of Type 2 diabetes, which can reduce the incidence of postprandial hyperglycemia. The existence of chronic postprandial hyperglycemia impaired the endogenous antioxidant defense by inducing oxidative stress-induced pancreatic β-cell destruction through uncontrolled generation of free radicals such as ROS, which in turn, leads to various macrovascular and microvascular complications. The currently available α -glucosidase inhibitors, for instance, acarbose, have some side effects such as hypoglycemia at higher doses, liver problems, meteorism, diarrhea, and lactic acidosis. Therefore, there is an urgent need to discover and develop potential α-glucosidase inhibitors.

OBJECTIVE

Based on suchmotifs, researchers are intrigued to search for the best scaffold that displays various biological activities. Among them, coumarin scaffold has attracted great attention. The compound and its derivatives can be isolated from various natural products and/or synthesized for the development of novel α-glucosidase inhibitors.

RESULTS

This study focused on coumarin and its derivatives as well as on their application as potent antidiabetic agents and has also concentrated on the structure-activity relationship.

CONCLUSION

This review describes the applications of coumarin-containing derivatives as α - glucosidase inhibitors based on published reports which will be useful for innovative approaches in the search for novel coumarin-based antidiabetic drugs with less toxicity and more potency.

Effect of processing on the contents of amino acids and fatty acids, and glucose release from the starch of quinoa

The effects of processing on the content of amino acids and fatty acids and the release of glucose from quinoa grains were evaluated in this paper. The processes included dehulling, boiling, extrusion, heating under pressure, and baking (infrared heating). The retention rate (AR) of essential amino acids and fatty acids of dehulled and boiled quinoa was 100%. The oil content of the extruded quinoa samples of two varieties was 47.71% and 39.75% lower than the corresponding raw quinoa samples. Baking and heating under pressure had different effects on the essential amino acid content, fatty acid content, and hydrolysis rate of quinoa starch. The results indicated the different cooking methods affect the essential amino acid content, fatty acid composition, release of glucose, and nutritional quality of quinoa, and moderate processing should be adopted to fully utilize the essential amino acids, fatty acids, and starch in quinoa.

In Vitro Evaluation of Antidiabetic and Anti-Inflammatory Activities of Polyphenolic-Rich Extracts from Anchusa officinalis and Melilotus officinalis

This study was focused on the phytochemical composition and biological activities of Anchusa officinalis and Melilotus officinalis polyphenolic-rich extracts obtained by nanofiltration. The high-performance liquid chromatography-mass spectrometry analysis showed that chlorogenic acid and rosmarinic acid were the main phenolic acids in both extracts. The main flavonoid compound from A. officinalis extracts is luteolin, whereas rutin and isoquercitrin are the main flavonoids in M. officinalis. M. officinalis polyphenolic-rich extract had the highest α-amylase (from hog pancreas) inhibitory activity (IC₅₀ = 1.30 ± 0.06 μg/mL) and α-glucosidase (from Saccharomyces cerevisiae) inhibitory activity (IC₅₀ = 92.18 ± 1.92 μg/mL). However, both extracts presented a significant α-glucosidase inhibitory activity. Furthermore, the hyaluronidase inhibition of polyphenolic-rich extracts also proved to be stronger (IC₅₀ = 11.8 ± 0.1 μg/mL for M. officinalis and 36.5 ± 0.2 μg/mL for A. officinalis), but there was moderate or low lipoxygenase inhibition. The studies on the fibroblast cell line demonstrated that both A. officinalis and M. officinalis polyphenolic-rich extracts possess the cytotoxic effect at a concentration higher than 500 μg/mL. The experimental data suggest that both extracts are promising candidates for the development of natural antidiabetic and anti-inflammatory food supplements.

Synthesis, Type II diabetes inhibitory activity, antimicrobial evaluation and docking studies of indeno[1,2-c]pyrazol-4(1H)-ones

We report a convenient and efficient synthesis of indeno[1,2-c]pyrazol-4(1H)-ones (4a‒o) by the reaction of a variety of 2-acyl-(1H)-indene-1,3(2H)-diones (1) and 2-hydrazinylbenzo[d]thiazole/2-hydrazinyl-6-substitutedbenzo[d]thiazoles (2) in the presence of glacial acetic acid in good yields. The structure of the compounds thus prepared were confirmed by analytical and spectral (FT-IR, ¹H NMR, ¹³C NMR, and HRMS) techniques. All the synthesized indeno[1,2-c]pyrazol-4(1H)-ones (4a‒o) were assayed for their in vitro Type II diabetes inhibitory activity by using Acarbose as standard drug and in vitro antimicrobial activity utilizing Streptomycin and Fluconazole as reference drugs. Among the synthesized derivatives, 4e (IC₅₀ = 6.71 μg/mL) was found to be more potent against α-glucosidase enzyme as compared with the standard Acarbose (IC₅₀ = 9.35 μg/mL) and 4i (IC₅₀ = 11.90 μg/mL) exhibited good inhibitory activity against α-amylase enzyme as compared with the standard Acarbose (IC₅₀ = 22.87 μg/mL). Also, all the titled compounds showed good antimicrobial activity. In addition, in vitro α-glucosidase and α-amylase inhibition were supported by docking studies performed on the derivatives 4e and 4o, respectively.

Study on the interaction of triaryl-dihydro-1,2,4-oxadiazoles with α-glucosidase

PURPOSE

One of the therapeutic approaches in the management of Type 2 diabetes is delaying the absorption of glucose through α-glucosidase enzymes inhibition, which can reduce the incidence of postprandial hyperglycemia. The existence of chronic postprandial hyperglycemia impaired the endogenous antioxidant defense due to inducing oxidative stress induced pancreatic β-cell destruction through uncontrolled free radicals generation such as ROS, which in turn, leads to various macrovascular and microvascular complications. This study aimed to synthesize 2-aryl-4,6-diarylpyrimidine derivatives, screen their α-glucosidase inhibitory activity, perform kinetic and molecular docking studies.

METHODS

A series of 3,4,5-triphenyl-4,5-dihydro-1,2,4-oxadiazole derivatives were synthesized and their α-glucosidase inhibitory activity was screened in vitro. Compounds 6a-k were synthesized via a two-step reaction with a yield between 65 and 88%. The structural elucidation of the synthesized derivatives was performed by different spectroscopic techniques. α-Glucosidase inhibitory activity of the oxadiazole derivatives 6a-k was evaluated against Saccharomyces cerevisiae α-glucosidase.

RESULTS

Most of the synthesized compounds demonstrated α-glucosidase inhibitory action. Particularly compounds 6c, 6d and 6 k were the most active compounds with IC₅₀ values 215 ± 3, 256 ± 3, and 295 ± 4 μM respectively. A kinetic study performed for compound 6c revealed that the compound is a competitive inhibitor of Saccharomyces cerevisiae α-glucosidase with K_i of 122 μM. The docking study also revealed that the two compounds, 6c and 6 k, have important binding interactions with the enzyme active site.

CONCLUSION

The overall results of our study reveal that the synthesized compounds could be a potential candidate in the search for novel α-glucosidase inhibitors to manage the postprandial hyperglycemia incidence. Graphical abstract.

Chemical and Bioactivity Evaluation of Eryngium planum and Cnicus benedictus Polyphenolic-Rich Extracts

This study evaluated the biological activities of Eryngium planum and of Cnicus benedictus extracts enriched in polyphenols obtained by nanofiltration. The HPLC-MS analysis showed that E. planum contains mainly flavonoids, especially rutin, while in C. benedictus extracts show the high concentration of the phenolic acids, principally the chlorogenic acid and sinapic acid. Herein, there is the first report of ursolic acid, genistin, and isorhamnetin in E. planum and C. benedictus. C. benedictus polyphenolic-rich extract showed high scavenging activity (IC₅₀=0.0081 mg/mL) comparable to that of standard compound (ascorbic acid) and a higher reducing power (IC₅₀= 0.082 mg/mL), with IC₅₀ having a significantly lower value than IC₅₀ for ascorbic acid. Both extracts were nontoxic to NCTC cell line. Among the investigated herbs, E. planum polyphenolic-rich extract showed the highest inhibitory activities with the IC₅₀ value of 31.3 μg/mL for lipoxygenase and 24.6 μg/mL for hyaluronidase. Both polyphenolic-rich extracts had a higher inhibitory effect on α-amylase and α-glucosidase than that of the acarbose. The synergistic effect of ursolic acid, rutin, chlorogenic acid, rosmarinic acid, genistin, and daidzein identified in polyphenolic-rich extracts could be mainly responsible for the pharmacological potentials of the studied extracts used in managing inflammation and diabetes.

Metabolite profiling and in vitro biological activities of two commercial bitter melon (Momordica charantia Linn.) cultivars

The current study was designed to characterize the metabolite profile and bioactivity of two commercial bitter melon (Momordica charantia Linn.) genotypes. UPLC-high resolution mass spectrometry (HRMS) was used to identify 15 phenolic and 46 triterpenoids in various bitter melon extracts. Total phenolic levels were the highest (57.28 ± 1.02) in methanolic extract of the inner tissue of Indian Green cultivar, which also correlated to the highest DPPH radical scavenging activity (30.48 ± 2.49 ascorbic acid equivalents (mg of AAE)/g of FD). In addition, highest levels of total saponins were observed in chloroform extract of the Chinese bitter melon pericarp (75.73 mg ± 4.67 diosgenin equivalents (DE)/g of FD). Differential inhibition of α-amylase and α-glucosidase activity was observed in response to polarity of extract, cultivar and tissue type. These results suggest that consumption of whole bitter melon may have potential health benefits to manage diabetes.

Effect of temperature and pH on the probiotication of Punica granatum juice using Lactobacillus species

This study was focused on the effects of fermentation temperature and pH on the quality of Punica granatum juice probioticated with Lactobacillus species: Lactobacillus plantarum, Lactobacillus casei, Lactobacillus bulgaricus, and Lactobacillus salivarius. The whole fruit juice of P. granatum which is rich with phytonutrients appeared to be a good probiotic carrier. The probiotication was carried out for 24 hr at 30, 35, and 37°C and pH 2.5, 4.0, and 5.5 under microaerophilic conditions. The results found that P. granatum juice cultivated with L. casei had a better growth profile with a higher biomass density at 37°C around pH 3.5-4.0. Probiotication could maintain the scavenging activity of P. granatum juice cultivated with L. casei. The scavenging activity achieved up to 90% inhibition at the concentration of 5 mg/ml. The whole fruit-squeezed P. granatum juice was suitable for the growth of Lactobacillus species even without supplementation during cultivation. PRACTICAL APPLICATIONS: The findings of this study presented the potential of P. granatum juice (whole fruit) to be used as a good probiotic carrier, particularly for Lactobacillus species without supplementation. High nutritious P. granatum juice catered the need of probiotic bacteria during fermentation. Probiotication could maintain the antioxidant capacity of the juice in term of its radical scavenging activity. The antioxidant capacity was mainly attributed to the metabolites such as phenolic acids (romarinic acid and caftaric acid) and flavonoids (quercetin, quercetin 3-glucoside, rutin and kaempferol rutinoside). With the optimized temperature (37°C) and pH (4.00), probiotic bacteria could growth well up to a cell viability of 2.46 × 10¹⁰  cfu/ml. This offers P. granatum to be developed into functional food to cater to the needs of the consumers who are lactose intolerant to dairy products.