α-Glucosidase and α-amylase inhibitors from seed oil: A review of liposoluble substance to treat diabetes

A cleaner and eco-friendly approach to simultaneous extraction and characterization of essential oil and pectin from Assam lemon peel and its application for energy generation through TENG devices

Scientists have been working on developing a green bio-TENG for portable remote devices, including wearables in the biomedical sector. The process involves obtaining pectin, a green material with anti-microbial properties, as a Triboelectric material. This study focuses on the extraction of essential oil (EO) and pectin from Assam lemon peel simultaneously. A single-step strategy was optimized using a central composite design-based response surface approach. The extracted pectin yielded 4.19 ± 0.31 % and 11.53 ± 0.11 %, respectively. GC-MS analysis revealed 52 volatile components in the Assam lemon EOs, with limonin being 94.47 % and β-Bisabolene being 1.26 %. Only khusilal was found in the EOs, a rare discovery in the scientific domain. The extracted pectin showed good purity and antimicrobial properties. The in vitro activities of the citrus EO against microbial cultures revealed its activity in controlling and eradicating bacterial and fungal growth. Hydro distillation followed by enzyme treatment is a promising approach that combines two separate extraction procedures. The produced biopolymer showed the generation of electrical signals under minimal pressure and stretching and prevented microbial degeneration when applied to a nanogenerator.

Unlocking the nutraceutical potential of Corylus avellana L. shells: microwave-assisted extraction of phytochemicals with antiradical and anti-diabetic properties

BACKGROUND

In recent years, the demand for high-quality natural extracts to be included in nutraceutical formulations has increased sharply. Hazelnut (Corylus avellana L.) shells (HZS) are underrated agricultural by-products that could be exploited as a source of active ingredients with pro-healthy properties. In the present study, a fully green microwave-assisted extraction (MAE) method was established for the first time aiming to recover bioactive constituents from HZS with significant nutraceutical value. Key MAE parameters, including ethanol in water concentration, microwave power, irradiation time and solvent-to-powder ratio, were optimized through response surface methodology utilizing a Box-Behnken design to achieve the highest total phenolic content and antioxidant/antiradical activities in the final extract.

RESULTS

The optimal MAE conditions (28% v/v ethanol/water, 270 s, 670 W, and 37 mL g-1) yielded an extract with significant scavenging capacity against reactive oxygen species and remarkable inhibitory activity towards both α-amylase (IC50 = 7.73 μg mL-1) and α-glucosidase (IC50 = 49.44 μg mL-1), demonstrating stronger hypoglycaemic properties than the anti-diabetic drug acarbose. Additionally, fluorescence spectroscopy results highlighted the ability of the optimized extract from HZS (OHS-E) to counteract advanced glycation end-product formation throughout the glycation cascade in a dose-dependent manner. Liquid chromatography/electrospray ionization-tandem mass spectrometry profiling unveiled the presence of fatty acids and phenolic compounds, including lignans, flavonoids, gallic acid derivatives and diarylheptanoids. Lastly, the biocompatibility of OHS-E was attested on HT29-MTX and Caco-2 intestinal cells.

CONCLUSION

Altogether, these findings encourage the potential application of OHS-E as an effective nutraceutical component against type 2 diabetes mellitus and oxidative stress. © 2024 The Author(s). Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Synthesis of modified Schiff base appended 1,2,4-triazole hybrids scaffolds: elucidating the in vitro and in silico α-amylase and α-glucosidase inhibitors potential

The current study involves the synthesis of Schiff bases based on 1,2,4-triazoles skeleton and assessing their α-amylase and α-glucosidase profile. Furthermore, the precise structures of the synthesized derivatives were elucidated using various spectroscopic methods such as 1H-NMR, 13C-NMR and HREI-MS. Using glimepiride as the reference standard, the in vitro α-glucosidase and α-amylase inhibitory activities of the synthesized compounds were evaluated in order to determine their potential anti-diabetic properties. All analogues showed varied range of inhibitory activity having IC50 values ranging from 17.09 ± 0.72 to 45.34 ± 0.03 μM (α-amylase) and 16.35 ± 0.42 to 42.31 ± 0.09 μM (α-glucosidase), respectively. Specifically, the compounds 1, 7 and 8 were found to be significantly active with IC50 values of 17.09 ± 0.72, 19.73 ± 0.42, and 23.01 ± 0.04 μM (against α-amylase) and 16.35 ± 0.42, 18.55 ± 0.26, and 20.07 ± 0.02 μM (against α-glucosidase) respectively. The obtained results were compared with the Glimepiride reference drug having IC50 values of 13.02 ± 0.11 μM (for α-glucosidase) and 15.04 ± 0.02 μM (for α-amylase), respectively. The structure-activity relationship (SAR) studies were conducted based on differences in substituent patterns at varying position of aryl rings A and B may cause to alter the inhibitory activities of both α-amylase and α-glucosidase enzymes. Additionally, the molecular docking study was carried out to explore the binding interactions possessed by most active analogues with the active sites of targeted α-amylase and α-glucosidase enzymes.

Elicitation of nutritional, antioxidant, and antidiabetic potential of barnyard millet (Echinochloa esculenta (A. Braun) H. Scholz) sprouts and microgreens through in vitro bio-accessibility assessment

This study has redirected focus towards the untapped potential of millets, exploring their utilization as small-scale vegetables like sprouts and microgreens. This study assessed the metabolite profiles and therapeutic efficacy of barnyard millets as sprouts and microgreens for antioxidant, anti-diabetic, and bioaccessibility properties. Based on the study, sprouts contained 456.52 mg GE/g of starch and microgreens contained 470.04 mg GE/g of carbohydrates, whereas the gastric phase of microgreens showed 426.85 mg BSAE/g, 397.6 mg LE/g, 348.19 g RE/g, and 307.40 g AAE/g of proteins, amino acids, vitamin A and vitamin C respectively. Secondary metabolites were significantly concentrated in the microgreen stage which is responsible for their increased antioxidant and antidiabetic potential than sprouts. This study validated the therapeutic and nutritional value of millet sprouts and microgreens by demonstrating their significant nutritional composition.

Establishment and application of a screening method for α-glucosidase inhibitors based on dual sensing and affinity chromatography

α-Glucosidase plays a direct role in the metabolic pathways of starch and glycogen, any dysfunction in its activity could result in metabolic disease. Concurrently, this enzyme serves as a target for diverse drugs and inhibitors, contributing to the regulation of glucose metabolism in the human body. Here, an integrated analytical method was established to screen inhibitors of α-glucosidase. This step-by-step screening model was accomplished through the biosensing and affinity chromatography techniques. The newly proposed sensing program had a good linear relationship within the enzyme activity range of 0.25 U mL-1 to 1.25 U mL-1, which can quickly identify active ingredients in complex samples. Then the potential active ingredients can be captured, separated, and identified by an affinity chromatography model. The combination of the two parts was achieved by an immobilized enzyme technology and a microdevice for reaction, and the combination not only ensured efficiency and accuracy for inhibitor screening but also eliminated the occurrence of false positive results in the past. The emodin, with a notable inhibitory effect on α-glucosidase, was successfully screened from five traditional Chinese medicines using this method. The molecular docking results also demonstrated that emodin was well embedded into the active pocket of α-glucosidase. In summary, the strategy provided an efficient method for developing new enzyme inhibitors from natural products.

Antidiabetic potential of thiazolidinedione derivatives with efficient design, molecular docking, structural activity relationship, and biological activity: an update review (2021-2023)

Thiazolidinedione has been used successfully by medicinal chemists all over the world in the development of potent antidiabetic derivatives. The few compounds with excellent antidiabetic potency that we have identified in this review could be used as a lead for further research into additional antidiabetic mechanisms. The information provided in this review regarding the design, biological activity, structure-activity relationships, and docking studies may be useful for scientists who wish to further explore this scaffold in order to fully utilize its biological potential and develop antidiabetic agents that would overcome the limitations of currently available medications for the treatment of diabetes. This review outlines the antidiabetic potential of Thiazolidinedione-based derivatives that have been published in the year 2021- till date.

An Update on Dipeptidyl Peptidase-IV Inhibiting Peptides

Diabetes is a chronic metabolic disorder. According to the International Diabetes Federation, about 537 million people are living with diabetes. The two types of diabetes are type 1 diabetes mellitus (T1DM) and type 2 diabetes mellitus (T2DM), among which the population affected by T2DM is relatively higher. A major reason for T2DM is that insulin stimulation is hampered due to the inactivation of incretin hormones. Dipeptidyl peptidase-IV (DPP-IV) is a serine protease that is directly involved in the inactivation of incretin hormones, e.g., glucagon-like peptide-1 (GLP-1). Therefore, the inhibition of DPP-IV can be a promising method for managing T2DM, in addition to other enzyme inhibition strategies, such as inhibition of α-amylase and α -glucosidase. Currently, about 12 different gliptin drugs are available in the market that inhibit DPP-IV in a dose-dependent manner. Instead of gliptins, 'peptides' can also be employed as an alternative and promising way to inhibit DPP-IV. Peptide inhibitors of DPP-IV have been identified from various plants and animals. Chemically synthesized peptides have also been experimented for inhibiting DPP-IV. Most peptides have been analysed by biochemical assays, whereas some in vitro assays have also been reported. Molecular docking analysis has been applied to comprehend the mechanism of inhibition. In this review, certain aspects of natural as well as synthetic peptides are described that have been proven to inhibit DPP-IV.

Fatty Acid Profiles and Biological Activities of the Vegetable Oils of Argania spinosa, Pinus halepensis and Pistacia atlantica Grown in Tunisia: A Preliminary Study

Several foods are used in both the nutraceutical and health sectors; vegetable oils, for example, can prevent the onset of numerous diseases. The properties of these oils are related to their chemical composition and primarily to the presence of fatty acids. The present work aimed to determine the chemical profiles of Argania spinosa, Pinus halepensis, and Pistacia altantica oils, used in traditional Tunisian foods, and to evaluate some biological properties. We evaluated their antioxidant, anti-enzymatic, antimicrobial, and anti-inflammatory properties. Linoleic acid was the main component of the three oils. P. atlantica oil showed more significant inhibitory activity against the enzymes studied than A. spinosa and P. halepensis. All three oils showed similar antioxidant and anti-inflammatory activity. Furthermore, A. spinosa and P. halepensis oils showed antibiofilm activity against P. aeruginosa, with 30-40% inhibition. These results focus on the possible use of these oils in the nutraceutical and healthcare sectors.

The inhibitory mechanism of amylase inhibitors and research progress in nanoparticle-based inhibitors

Type 2 diabetes is caused by persistently high blood sugar levels, which leads to metabolic dysregulation and an increase in the risk of chronic diseases such as diabetes and obesity. High levels of rapidly digestible starches within foods may contribute to high blood sugar levels. Amylase inhibitors can reduce amylase activity, thereby inhibiting starch hydrolysis, and reducing blood sugar levels. Currently, amylase inhibitors are usually chemically synthesized substances, which can have undesirable side effects on the human body. The development of amylase inhibitors from food-grade ingredients that can be incorporated into the human diet is therefore of great interest. Several classes of phytochemicals, including polyphenols and flavonoids, have been shown to inhibit amylase, including certain types of food-grade nanoparticles. In this review, we summarize the main functions and characteristics of amylases within the human body, as well as their interactions with amylase inhibitors. A strong focus is given to the utilization of nanoparticles as amylase inhibitors. The information covered in this article may be useful for the design of functional foods that can better control blood glucose levels, which may help reduce the risk of diabetes and other diet-related diseases.

Designing sustainable weaning foods for developing countries: not only a matter of nutrients

Blended complementary foods from cereals and high-protein sources are used worldwide to cope with infants' malnutrition. However, the usefulness of the food matrix during traditional processes reaches suboptimal effectiveness due to cereal gelatinization and viscosity, which reduce consumption. The interplay between nutritional and physical qualities needed for weaning children presents further significant constraints. A combination of processing methods can improve and optimize the overall product quality. This paper investigated the nutritional, functional, and anti-nutritional factors of a complementary infant porridge made by combining fermented sorghum flour with germinated bottle gourd seed flour. Overall, the combination improved the functional and physical properties of the porridge suitable for children of 10 months and over. A serving of 100 g would contribute 115-145% and 23-31% of the recommended nutritional intake of protein and energy, respectively, for low breast milk energy between 6-24 months. The results demonstrate that a combination of strategies and technologies are needed to balance nutritional and physical quality.

Alpha-Glucosidase Inhibitory Peptides: Sources, Preparations, Identifications, and Action Mechanisms

With the change in people's lifestyle, diabetes has emerged as a chronic disease that poses a serious threat to human health, alongside tumor, cardiovascular, and cerebrovascular diseases. α-glucosidase inhibitors, which are oral drugs, have proven effective in preventing and managing this disease. Studies have suggested that bioactive peptides could serve as a potential source of α-glucosidase inhibitors. These peptides possess certain hypoglycemic activity and can effectively regulate postprandial blood glucose levels by inhibiting α-glucosidase activity, thus intervening and regulating diabetes. This paper provides a systematic summary of the sources, isolation, purification, bioavailability, and possible mechanisms of α-glucosidase inhibitory peptides. The sources of the α-glucosidase inhibitory peptides were introduced with emphasis on animals, plants, and microorganisms. This paper also points out the problems in the research process of α-glucosidase inhibitory peptide, with a view to providing certain theoretical support for the further study of this peptide.

Design, synthesis and antidiabetic study of triazole clubbed indole derivatives as α-glucosidase inhibitors

α -Glucosidase is an enzyme present near the brush boundary of the small intestine that is essential in the hydrolysis of carbohydrates to glucose. Because inhibiting this enzyme slows the release of glucose, α-Glucosidase inhibitors are appealing medications for treating diabetes as a carbohydrate-related illness. The present study includes the design, synthesis and antidiabetic potential of novel triazole based indole derivatives as α-glucosidase inhibitor. Among them, the compound R1 was found to be most potent with promising candidate with IC50 value of 10.1 μM and R2 and R3 showed the good inhibitory potency with IC50 values 12.95 μM, 11.35 μM, respectively when compared to the standard drug acarbose having IC50 value of 13.5 μM. In in vivo studies, body weight of the mice was increased when compared to standard drug acarbose, the blood glucose level of the mice was decreased, same as the total cholesterol level, LDL, and triglycerides level decreased in comparison to standard drug. The level HDL was increased as it is a good cholesterol in comparison to standard drug acarbose. Furthermore, these synthesized compounds were docked with α-glucosidase using PDB ID:3WY1 which showed that compound R1 having good docking score -6.734 kcal/mol and compound R2, R3 showed docking score -6.14, -6.10 kcal/mol, respectively when compared with standard acarbose having docking score -4.55 kcal/mol. R1 showed the similar interaction with amino acid PHE166, GLU271, comparison with standard drug Acarbose. The synthesized compounds have been confirmed for antidiabetic activity and may be used for further development of potent compounds.

In Vitro and in silico studies to explore potent antidiabetic inhibitor against human pancreatic alpha-amylase from the methanolic extract of the green microalga Chlorella vulgaris

Today's era and lifestyle have led to a quick rise in cases of diabetes. Diabetes mellitus (DM) has risen to the top of the list of serious diseases and stems from different health disorders. Human pancreatic alpha-amylase (HPA) enzyme plays a critical role in the digestion of carbohydrates, and inhibitors of alpha-amylase have been investigated as a way to slow the absorption of carbohydrates and reduce postprandial (after meal) hyperglycemia in patients with diabetes. Recently algal derivatives have been studied for their potential as a new drug against diabetes and other diseases. The study is aimed to find active biochemical compounds from the methanolic extract of Chlorella vulgaris. The in vitro studies were carried out and the results revealed that methanolic extract from C. vulgaris showed abundant inhibition efficacy of the α-amylase (IC50 of about 2.66 µg/mL) compared to acarbose (IC50 of about 2.85 µg/mL), a standard, commercial inhibitor. All the bioactive compounds from the methanolic extract were identified from the GCMS study and considered for in silico evaluation. Out of 14 bioactive compounds from GCMS, compound C3 showed higher docking energy (-8.3 kcal/mol) compared to other compounds. Subsequently, the comparative molecular dynamic simulation of apo and ligand-bound (compound C3 and acarbose) α-amylase complexes showed overall structural stability for compound C3 at the active site of α-amylase from various MD analyses. Hence, we believe, the bioactive compounds identified from GCMS may assist in diabetic therapeutics. Moreover, the compound C3 identified in this study could be a potential antidiabetic therapeutic inhibitor.Communicated by Ramaswamy H. Sarma.

Study of the Phytochemical Composition, Antioxidant Properties, and In Vitro Anti-Diabetic Efficacy of Gracilaria bursa-pastoris Extracts

In this study, a comparison was made of the chemical makeup of different extracts obtained from Gracilaria bursa-pastoris, a type of red seaweed that was gathered from the Nador lagoon situated in the northern part of Morocco. Additionally, their anti-diabetic and antioxidant properties were investigated. The application of GC-MS technology to analyze the fatty acid content of the samples revealed that linoleic acid and eicosenoic acid were the most abundant unsaturated fatty acids across all samples, with palmitic acid and oleic acid following in frequency. The HPLC analysis indicated that ascorbic and kojic acids were the most prevalent phenolic compounds, while apigenin was the most common flavonoid molecule. The aqueous extract exhibited significant levels of polyphenols and flavonoids, registering values of 381.31 ± 0.33 mg GAE/g and 201.80 ± 0.21 mg QE/g, respectively. Furthermore, this particular extract demonstrated a remarkable ability to scavenge DPPH radicals, as evidenced by its IC₅₀ value of 0.17 ± 0.67 mg/mL. In addition, the methanolic extract was found to possess antioxidant properties, as evidenced by its ability to prevent β-carotene discoloration, with an IC₅₀ ranging from 0.062 ± 0.02 mg/mL to 0.070 ± 0.06 mg/mL. In vitro study showed that all extracts significantly inhibited the enzymatic activity of α-amylase and α-glucosidase. Finally, molecular docking models were applied to assess the interaction between the primary phytochemicals identified in G. bursa-pastoris extracts and the human pancreatic α-amylase and α-glucosidase enzymes. The findings suggest that these extracts contain bioactive substances capable of reducing enzyme activity more effectively than the commercially available drug acarbose.

Optimizing glycation control in diabetes: An integrated approach for inhibiting nonenzymatic glycation reactions of biological macromolecules

Diabetes is a multifactorial disorder that increases mortality and disability due to its complications. A key driver of these complications is nonenzymatic glycation, which generates advanced glycation end-products (AGEs) that impair tissue function. Therefore, effective nonenzymatic glycation prevention and control strategies are urgently needed. This review comprehensively describes the molecular mechanisms and pathological consequences of nonenzymatic glycation in diabetes and outlines various anti-glycation strategies, such as lowering plasma glucose, interfering with the glycation reaction, and degrading early and late glycation products. Diet, exercise, and hypoglycemic medications can reduce the onset of high glucose at the source. Glucose or amino acid analogs such as flavonoids, lysine and aminoguanidine competitively bind to proteins or glucose to block the initial nonenzymatic glycation reaction. In addition, deglycation enzymes such as amadoriase, fructosamine-3-kinase, parkinson's disease protein, glutamine amidotransferase-like class 1 domain-containing 3A and terminal FraB deglycase can eliminate existing nonenzymatic glycation products. These strategies involve nutritional, pharmacological, and enzymatic interventions that target different stages of nonenzymatic glycation. This review also emphasizes the therapeutic potential of anti-glycation drugs for preventing and treating diabetes complications.

Bioactive compounds from Polygonatum genus as anti-diabetic agents with future perspectives

Diabetes mellitus (DM) is one of the most serious health problems worldwide. Species in the genus Polygonatum are traditional food and medicinal plants, which play an important role in controlling blood glucose. In this reveiw, we systematically summarized the traditional and modern applications of the genus Polygonatum in DM, focused on the material bases of polysaccharides, flavonoids and saponins. We highlighted their mechanisms of action in preventing obese diabetes, improving insulin resistance, promoting insulin secretion, regulating intestinal microecology, inhibiting advanced glycation end products (AGEs) accumulation, suppressing carbohydrate digestion and obsorption and modulating gluconeogenesis. Based on the safety and efficacy of this 'medicinal food' and its utility in the prevention and treatment of diabetes, we proposed a research and development program that includs diet design (supplementary food), medical nutrition therapy and new drugs, which could provide new pathways for the use of natural plants in prevention and treatment of DM.

Inhibitory mechanism of phenolic compounds in rapeseed oil on α-amylase and α-glucosidase: Spectroscopy, molecular docking, and molecular dynamic simulation

Developing naturally active components to control α-amylase/α-glucosidase activity is highly desired for preventing and managing type 2 diabetes. Rapeseed oil is rich in active phenolic compounds and seed oil is a major source of liposoluble inhibitors to these enzymes. However, it remains unclear about the interaction of phenolic compounds in rapeseed oil with α-amylase/α-glucosidase. This study found that the important phenolic compounds from rapeseed oil (Sinapic acid, SA; canolol, CAO; canolol dimer, CAO dimer) possessed effective inhibition performance against α-amylase and α-glucosidase. CAO showed the lowest and highest inhibitory effect, respectively. In the kinetics studies, the inhibition mechanism of SA/CAO/CAO dimer against α-glucosidase was non-competitive, exhibiting a different way from α-amylase. Fluorescence quenching spectra implied that the static processes were responsible for the spontaneous binding between the compounds and enzymes. Fourier-transform infrared spectroscopy (FT-IR) displayed these compounds-induced conformation alterations of α-amylase/α-glucosidase. Molecular docking revealed that SA/CAO/CAO dimer decreased the catalytic efficiency of α-amylase/α-glucosidase through hydrogen bonds, hydrophobic force, or π-π interaction. Molecular dynamics matched well with the experimental and docking results regarding the inhibitory behaviors and interactions toward α-amylase/α-glucosidase. These results demonstrated the potential benefits of phenolic compounds from rapeseed oil in antidiabetic-related activities.

Glucoregulatory Properties of Fermented Soybean Products

Type 2 diabetes mellitus is a chronic metabolic disease, characterized by persistent hyperglycemia, the prevalence of which is on the rise worldwide. Fermented soybean products (FSP) are rich in diverse functional ingredients which have been shown to exhibit therapeutic properties in alleviating hyperglycemia. This review summarizes the hypoglycemic actions of FSP from the perspective of different target-related molecular signaling mechanisms in vitro, in vivo and clinical trials. FSP can ameliorate glucose metabolism disorder by functioning as carbohydrate digestive enzyme inhibitors, facilitating glucose transporter 4 translocation, accelerating muscular glucose utilization, inhibiting hepatic gluconeogenesis, ameliorating pancreatic dysfunction, relieving adipose tissue inflammation, and improving gut microbiota disorder. Sufficiently recognizing and exploiting the hypoglycemic activity of traditional fermented soybean foods could provide a new strategy in the development of the food fermentation industry.

Discovery, Validation, and Target Prediction of Antibacterial and Antidiabetic Components of Archidendron clypearia Based on a Combination of Multiple Analytical Methods

Archidendron clypearia (A. clypearia), a Fabaceae family member, is widely used as an anti-inflammatory herbal medicine; however, its antibacterial and antidiabetic properties have not been extensively investigated. This study aimed to systematically analyze the antibacterial and antidiabetic components of A. clypearia by utilizing a combination of analytical methods. First, ten different polarity extracts were analyzed through ultra-performance liquid chromatography (UPLC), and their antibacterial and antidiabetic activities were evaluated. Then the spectrum-effect relationship between the biological activity and UPLC chromatograms was analyzed by partial least squares regression and gray relational analysis, followed by corresponding validation using isolated components. Finally, network pharmacology and molecular docking were implemented to predict the main antibacterial target components of A. clypearia and the enzyme inhibition active sites of α-amylase and α-glucosidase. P15, P16, and P20 were found to be the antibacterial and antidiabetic active components. The inhibitory effect of 7-O-galloyltricetiflavan (P15) on six bacterial species may be mediated through the lipid and atherosclerosis pathway, prostate cancer, adherens junctions, and targets such as SRC, MAPK1, and AKT1. The molecular docking results revealed that 7-O-galloyltricetiflavan and 7,4'-di-O-galloyltricetiflavan (P16/P20) can bind to α-amylase and α-glucosidase pockets with binding energies lower than -6 kcal/mol. Our study provides guidance for the development of antibacterial and antidiabetic products based on A. clypearia and can be used as a reference for the evaluation of bioactivity of other herbs.

Real time monitoring and evaluation of the inhibition effect of fucoxanthin against α-amylase activity by using QCM-A

The main symptoms of diabetes are hyperglycemia and insulin resistance. The inhibition of the starch digestion enzymes could effectively regulate starch digestion and glucose absorption, thereby slowing or treating the symptoms of postprandial hyperglycemia. Herein, we used fucoxanthin isolated from Undaria pinnatifida stems, as α-amylase inhibitor, and monitored the interactions of both biomolecules by using quartz crystal microbalance-admittance (QCM-A) instrument. All the processes of α-amylase hydrolysis of starch were also dynamically tracked by using amylose-immobilized QCM technology. In our work, we found that the kinetic parameter (k _off, k _on, and k _cat) values obtained by the QCM-A analysis were relatively consistent compared to the kinetic parameter values obtained by the conventional Michaelis-Menten analysis. For the inhibitory reactions, the results showed that fucoxanthin significantly reduced the activity of α-amylase in a dose-dependent manner. The QCM-A technology shown to be an excellent approach in obtaining comprehensive and accurate kinetic parameters, thereby providing real and accurate data for kinetic studies. It is helpful to clarify the mechanism of action of fucoxanthin on α-amylase, which further proved the potential of fucoxanthin to improve and treat postprandial hyperglycemia.

Chemical Constituents, Antioxidant, and Enzyme Inhibitory Activities Supported by In-Silico Study of n-Hexane Extract and Essential Oil of Guava Leaves

Psidium guajava (Guava tree) is one of the most widely known species in the family Myrtaceae. The Guava tree has been reported for its potential antioxidant, anti-inflammatory, antimicrobial, and cytotoxic activities. In the current study, the chemical compositions of the n-hexane extract and the essential oil of P. guajava were investigated using the GC/MS analysis, along with an evaluation of their antioxidant potential, and an investigation into the enzyme inhibition of acetylcholinesterase (AChE), butyrylcholinesterase (BchE), tyrosinase, α-amylase, and α-glucosidase. Moreover, molecular docking of the major identified active sites of the target enzymes were investigated. The chemical characterization of the n-hexane extract and essential oil revealed that squalene (9.76%), α-tocopherol (8.53%), and γ-sitosterol (3.90%) are the major compounds in the n-hexane extract. In contrast, the major constituents of the essential oil are D-limonene (36.68%) and viridiflorol (9.68%). The n-hexane extract showed more antioxidant potential in the cupric reducing antioxidant capacity (CUPRAC), the ferric reducing power (FRAP), and the metal chelating ability (MCA) assays, equivalent to 70.80 ± 1.46 mg TE/g, 26.01 ± 0.97 mg TE/g, and 24.83 ± 0.35 mg EDTAE/g, respectively. In the phosphomolybdenum (PM) assay, the essential oil showed more antioxidant activity equivalent to 2.58 ± 0.14 mmol TE/g. The essential oil demonstrated a potent BChE and tyrosinase inhibitory ability at 6.85 ± 0.03 mg GALAE/g and 61.70 ± 3.21 mg KAE/g, respectively. The α-amylase, and α-glucosidase inhibitory activity of the n-hexane extract and the essential oil varied from 0.52 to 1.49 mmol ACAE/g. Additionally, the molecular docking study revealed that the major compounds achieved acceptable binding scores upon docking with the tested enzymes. Consequently, the P. guajava n-hexane extract and oil can be used as a promising candidate for the development of novel treatment strategies for oxidative stress, neurodegeneration, and diabetes mellitus diseases.

Hyphaene thebaica (Areceaeae) as a Promising Functional Food: Extraction, Analytical Techniques, Bioactivity, Food, and Industrial Applications

Hyphaene thebaica, also known as doum, is a wild plant growing in Egypt, Sudan, and other African countries. It is usually used to prepare nutritive diets, tasty beverages, and other food products. This review aimed to highlight the phytochemical composition of the doum plant using NMR, GC–MS, HPLC, and UPLC/Qtof/MS. The reported active constituents are also described, with flavonoids, phenolic acids, and saponins being the most dominant components. Extraction methods, both conventional and non-conventional, and their existing parameters were summarized. The in vitro and in vivo studies on the extracts and active constituents were also reported. We focused on different applications of doum in functional food products, animal feeding systems, and pharmaceutical applications. Doum is considered a promising dietary and therapeutic candidate to be applied on a wider scale. Proteomic analysis of doum and clinical assessment are still lacking and warrant further investigations in the future.

Effect-directed analysis in food by thin-layer chromatography assays

Thin-layer chromatography (TLC) is widely used for food analysis and quality control. As an open chromatographic system, TLC is compatible with microbial-, biochemical-, and chemical-based derivatization methods. This compatibility makes it possible to run in situ bioassays directly on the plate to obtain activity-profile chromatograms, i.e., the effect-directed analysis of the sample. Many of the properties that can be currently measured using this assay format are related to either desired or undesired features for food related products. The TLC assays can detect compounds related to the stability of foods (antioxidant, antimicrobial, antibrowning, etc.), contaminants (antibiotics, pesticides, estrogenic compounds, etc.), and compounds that affect the absorption, metabolism or excretion of nutrients and metabolites or could improve the consumers health (enzyme inhibitors). In this article, different food related TLC-assays are reviewed. The different detection systems used, the way in which they are applied as well as selected examples are discussed.

Evaluation of different agricultural wastes for the production of polysaccharides from Oudemansiella raphanipes and its antioxidant properties

Oudemansiella raphanipes (OR) is a commercial mushroom which possesses high nutritional value and excellent and unique flavors. In this study, various agricultural wastes were utilized as substitute materials in the low-cost and high-yield production of mycelia biomass and polysaccharides by liquid fermentation. The sawdust, wheat bran, apple pomace, sugarcane, and corn particles were employed to cultivate OR, using the potato dextrose broth as control. Additionally, a preliminary characterization and in vitro antioxidant activities of partial purified OR polysaccharides were investigated. The substrate of sugarcane was suitable for mycelia growth of OR, with high yield of mycelia biomass and polysaccharides content. In vitro antioxidant activity assays demonstrated that OR polysaccharides could effectively scavenge 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) and 1,1-diphenyl-2-picrylhydrazyl radicals. OR polysaccharides had configuration as revealed by Fourier transform infrared, and was mainly composed of fucose (Fuc), rhamnose (Rha), arabinose (Ara), galactose (Gal), glucose (Glc), xylose (Xyl), mannose (Man), ribose (Rib), and galacturonic acid (Gal-UA), with mass percentages of 3.29%, 0.64%, 1.09%, 16.03%, 72.69%, 0.56%, 3.18%, 0.93%, and 1.59%, respectively. This study may offer support for decreasing the cost of OR polysaccharides production and dealing with these agricultural wastes.

Evaluation of anthoxanthins and their actions on digestive enzyme inhibition when used independently and in combination

Carbohydrate digestibility is a key determinant for elevated postprandial hyperglycemia (PPHG). Apart from dietary restrictions, one of the strategies to reduce PPHG is to limit the activity of carbohydrate digestive enzymes within the gastrointestinal tract in order to reduce monosaccharide absorption rates. The present work aimed to assess the inhibitory capabilities of digestive enzymes (e.g., α-glucosidase and α-amylase) by anthoxanthins when used independently, in combination with acarbose, or with a different anthoxanthin. Our results showed that quercetin, myricetin, and luteolin presented lower IC₅₀ values than acarbose and inhibited α-glucosidase through mixed-type inhibition. On the other hand, acarbose when compared with these anthoxanthins, remained the most potent inhibitor of α-amylase. Combinatorial treatment (i) acarbose-quercetin and (ii) myricetin-luteolin showed synergistic activity (CI value less than 0.9) in α-glucosidase inhibition. An additive effect (CI value between 0.9 and 1.1) in α-glucosidase inhibition was observed when acarbose-myricetin, acarbose-luteolin or when a combination of two different anthoxanthins (quercetin-myricetin and quercetin-luteolin) was used. This study suggests the potential use of anthoxanthins as functional food ingredients to mitigate PPHG towards the management of T2DM.

Responsive Fluorescent Coumarin–Cinnamic Acid Conjugates for α-Glucosidase Detection

α-Glucosidase is a potent drug target for treating type II diabetes mellitus. A great number of α-glucosidase inhibitors have been developed based on the molecular skeletons of bioactive natural products. However, efficient fluorescent probes for α-glucosidase detection are still limited, not to mention the probes with additional inhibitory functions. In this work, aiming for the enzyme’s highly specific detection, we designed and synthesized two environmentally sensitive fluorescent probes, namely, LD01 and LD02, respectively, based on conjugates of coumarin and cinnamic acid derivatives. We found a significant responsive emission enhancement upon LD02’s binding to α-glucosidase. These newly designed probes can act as a simple but efficient tool to evaluate the binding affinity of α-glucosidase to their inhibitors.

β-Sitosterol Glucoside-Loaded Nanosystem Ameliorates Insulin Resistance and Oxidative Stress in Streptozotocin-Induced Diabetic Rats

β-Sitosterol glucoside (SG), isolated from Senecio petasitis (Family Asteraceae), was loaded in self-nanoemulsifying drug delivery systems (SEDDS) in a trial to enhance its solubility and biological effect. Various co-surfactants were tested to prepare a successful SEDDS. The selected SG-loaded SEDDS had a droplet size of 134 ± 15.2 nm with a homogenous distribution (polydispersity index 0.296 ± 0.02). It also demonstrated a significant augmentation of SG in vitro release by 4-fold compared to the free drug suspension. The in vivo insulin sensitivity and antidiabetic effect of the prepared SG-loaded SEDDS were further assessed in streptozotocin-induced hyperglycemic rats. The hypoglycemic effect of SG-loaded nanosystem was evidenced by decreased serum glucose and insulin by 63.22% and 53.11%, respectively. Homeostasis model assessment-insulin resistance (HOMA-IR) index demonstrated a significant reduction by 5.4-fold in the diabetic group treated by SG-loaded nanosystem and exhibited reduced glucagon level by 40.85%. In addition, treatment with SG-loaded nanosystem significantly decreased serum MDA (malondialdehyde) and increased catalase levels by 38.31% and 64.45%, respectively. Histopathological investigations also supported the protective effect of SG-loaded nanosystem on the pancreas. The promising ability of SG-loaded nanosystem to ameliorate insulin resistance, protect against oxidative stress, and restore pancreatic β-cell secretory function warrants its inclusion in further studies during diabetes progression.

Health Beneficial Phytochemicals in Dioscorea caucasica Lipsky Leaves and Tubers and Their Inhibitory Effects on Physiologically Important Enzymes

Dioscorea caucasica Lipsky is a tertiary relict endemic plant naturally growing in the western part of the trans-Caucasus regions; it has adapted and successfully grows in the temperate region of the Baltic countries. Information about its phytochemical composition and bioactivities is rather scarce. This study reports the results of the identification of 41 compounds in D. caucasica leaf and tuber hydroethanolic extracts using UPLC-QTOF/MS. Organic acids were found in both extracts; hydroxycinnamates and flavonoids were the main phytochemicals in the leaves, while steroidal glycosides, fatty acids (mainly hydroxylated) and carbohydrates were found in the tubers. Leaf extracts inhibited enzymes in a dose-dependent manner and were remarkably stronger inhibitors of physiologically important enzymes, namely α-amylase (48.6% at 480 µg/mL), α-glucosidase (IC50 = 41.99 and 47.95 µg/mL with and without 0.1 M Na2CO3), acetylcholinesterase (45.85% at 100 µg/mL) and angiotensin-converting enzyme (IC50 = 829.7 µg/mL), most likely due to the presence of some quantified polyphenolic antioxidants. The mode of inhibition of α-glucosidase and acetylcholinesterase was assessed via kinetic studies based on Lineweaver–Burk inhibition plots. Leaf and tuber extracts acted as mixed-type and competitive inhibitors of α-glucosidase, respectively; the leaf extract demonstrated an uncompetitive inhibition mode of acetylcholinesterase. It is expected that this new knowledge of D. caucasica will serve for its valorization in developing new health beneficial ingredients for functional foods and nutraceuticals.

Construction of fatty acid derivatives from rubber seed oil as α-glucosidase inhibitors based on rubber seed oil

Natural free fatty acids show inhibitory effects on α-glucosidase and can hence have potential applications in diabetes treatment. This study indicated that the inhibitory effect of fatty acids showed a significant negative correlation with affinity energy (- 0.87) and melting point (- 0.88). Guided by this relationship, two promotion strategies of hydration and esterification were put forward to increase the inhibitory effect of fatty acids on α-glucosidase. The hydration can import an extra hydroxy group into the C=C bond of fatty acids, that will enhance the interaction with α-glucosidase, while the esterification will lower the melting point of fatty acids, and promote the inhibitory effect. Hydroxy fatty acids and fatty acid isopropyl esters possessed higher inhibitory effects than the natural fatty acids. Then, rubber seed oil was modified into novel fatty acid derivatives with higher inhibitory effect on α-glucosidase. The inhibitory IC50 of hydroxy products and isopropanol esters was 0.42 ± 0.01 μM and 0.57 ± 0.01 μM, respectively. The result reveals a feasible route to construct fatty acid derivatives from natural oil with α-glucosidase inhibitory effect.

Inhibitory effects of a low-molecular-weight sulfated fucose-containing saccharide on α-amylase and α-glucosidase prepared from ascophyllan

To find natural and safe anti-diabetic foods or potential drugs, low-molecular-weight saccharide fragments LMWAs-H (M_w 33.48 kDa) and LMWAs-L (M_w 6.71 kDa) from the sulfated polysaccharide ascophyllan of Ascophyllum nodosum using alginate lyase (EC 4.2.2.3) were investigated. The results revealed that LMWAs-H possessed potent inhibition activity against α-glucosidase or α-amylase in a concentration-dependent manner, which were higher than native ascophyllan or LMWAs-L. LMWAs-H exhibited a stronger inhibitory activity against α-glucosidase than α-amylase because it differently affects the conformational structures of these enzymes. Structural analysis revealed LMWAs-H to be →4)-α-L-Fucp-(1 → 4)-α-L-Fucp-(1 → 3)-β-D-Xylp-(1 → 3)-α-L-Fucp4S(1→ as main chain, and T-α-D-Glcp-(1→ and →3)-β-D-ManpA_red residues were attached to the ends of main chain as non-reducing- and reducing-end residues, respectively. The 4-deoxy-L-erythro-hex-4-enuronosyluronate linked the O-4 position of →3,4)-β-D-ManpA_red residue as side branches. Our results suggest that LMWAs-H is the main active structural motif responsible for the enzymes-inhibiting activities, which is probably derived from the fucose-containing branches of ascophyllan. Our findings reveal that the strong inhibition of LMWAs-H on α-glucosidase but mild inhibition on α-amylase is highly related to its structural properties, suggesting its desirable characteristics as an anti-diabetic agent.

The regulatory effect of total flavonoids of Sedum aizoon L. on oxidative stress in type 1 diabetic mice

In this study, the optimal extraction conditions for the total flavonoids of Sedum aizoon L. (STF) were optimized by response surface methodology. Evaluation of the antioxidant in vitro of STF, and modulatory effects of glucolipid metabolism, and oxidative stress in mice with type 1 diabetes mellitus (T1DM). STF showed good antioxidant capacity in vitro. STF could improve glucolipid metabolism, organ coefficients, and antioxidant stress enzymes in T1DM mice effectively, reduce the damage to liver tissue, and regulate redox imbalance in the organism by modulating the Nrf2/Keap1/ARE signaling pathway. The results of this study could provide a theoretical reference for the application of Sedum aizoon L. in the development of auxiliary hypoglycemic functional foods and improvement of diabetes.

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Optimization of optimal extraction conditions by response surface methodology.

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Total flavonoids of Sedum aizoon L. have good antioxidant activity in vitro.

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Total flavonoids of Sedum aizoon L. have hypoglycemic effect.

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Total flavonoids of Sedum aizoon L. can improve the oxidative stress in T1DM mice.

Syringa microphylla Diels: A comprehensive review of its phytochemical, pharmacological, pharmacokinetic, and toxicological characteristics and an investigation into its potential health benefits

BACKGROUND

Syringa microphylla Diels is a plant in the family Syringa Linn. For hundreds of years, its flowers and leaves have been used as a folk medicine for the treatment of cough, inflammation, colds, sore throat, acute hepatitis, chronic hepatitis, early liver cirrhosis, fatty liver, and oesophageal cancer.

PURPOSE

For the first time, we have comprehensively reviewed information on Syringa microphylla Diels that is not included in the Pharmacopoeia, clarified the pharmacological mechanisms of Syringa microphylla Diels and its active ingredients from a molecular biology perspective, compiled in vivo and in vitro animal experimental data and clinical data, and summarized the toxicology and pharmacokinetics of Syringa microphylla Diels. The progress in toxicology research is expected to provide a theoretical basis for the development of new drugs from Syringa microphylla Diels, a natural source of compounds that are potentially beneficial to human health.

METHODS

The PubMed, Google Scholar, China National Knowledge Infrastructure, Web of Science, SciFinder Scholar and Thomson Reuters databases were utilized to conduct a comprehensive search of published literature as of July 2021 to find original literature related to Syringa microphylla Diels and its active ingredients.

RESULTS

To date, 72 compounds have been isolated and identified from Syringa microphylla Diels, and oleuropein, verbascoside, isoacteoside, echinacoside, forsythoside B, and eleutheroside B are the main active components. These compounds have antioxidant, antibacterial, anti-inflammatory, and neuroprotective effects, and their safety and effectiveness have been demonstrated in long-term traditional applications. Molecular pharmacology experiments have indicated that the active ingredients of Syringa microphylla Diels exert their pharmacological effects in various ways, primarily by reducing oxidative stress damage via Nrf2/ARE pathway regulation, regulating inflammatory factors and inducing apoptosis through the MAPK and NF-κB pathways.

CONCLUSION

This comprehensive review of Syringa microphylla Diels provides new insights into the correlations among molecular mechanisms, the importance of toxicology and pharmacokinetics, and potential ways to address the limitations of current research. As Syringa microphylla Diels is a natural low-toxicity botanical medicine, it is worthy of development and utilization and is an excellent choice for treating various diseases.

Anti-diabetics and antimicrobials: Harmony of mutual interplay

Diabetes is one of the four major non-communicable diseases, and appointed by the world health organization as the seventh leading cause of death worldwide. The scientists have turned over every rock in the corners of medical sciences in order to come up with better understanding and hence more effective treatments of diabetes. The continuous research on the subject has elucidated the role of immune disorders and inflammation as definitive factors in the trajectory of diabetes, assuring that blood glucose adjustments would result in a relief in the systemic stress leading to minimizing inflammation. On a parallel basis, microbial infections usually take advantage of immunity disorders and propagate creating a pro-inflammatory environment, all of which can be reversed by antimicrobial treatment. Standing at the crossroads between diabetes, immunity and infection, we aim in this review at projecting the interplay between immunity and diabetes, shedding the light on the overlapping playgrounds for the activity of some antimicrobial and anti-diabetic agents. Furthermore, we focused on the anti-diabetic drugs that can confer antimicrobial or anti-virulence activities.

Anethum sowa Roxb. ex fleming: A review on traditional uses, phytochemistry, pharmacological and toxicological activities

ETHNOPHARMACOLOGICAL RELEVANCE

Anethum sowa Roxb. ex Fleming (Syn. Peucedanum sowa Roxb. ex Fleming, Family: Apiaceae) is a pharmacologically important as aromatic and medicinal plant. Various parts of this plant are used in traditional medicine systems for carminative, uterine and colic pain, digestion disorder, flatulence in babies, appetite-stimulating agent and used to treat mild flue and cough. The essential oil is used for aromatherapy. It is also used as a spice for food flavouring and culinary preparations in many Asian and European countries.

AIM OF THE REVIEW

This review aims to provide a comprehensive and critical assessment from the reported traditional and pharmaceutical uses and pharmacological activities of the extracts, essential oil and phytoconstituents with emphasis on its therapeutic potential as well as toxicological evaluation of A. sowa.

MATERIALS AND METHODS

Online search engines such as SciFinder®, GoogleScholar®, ResearchGate®, Web of Science®, Scopus®, PubMed and additional data from books, proceedings and local prints were searched using relevant keywords and terminologies related to A. sowa for critical analyses.

RESULTS

The literature studies demonstrated that A. sowa possesses several ethnopharmacological activities, including pharmaceutical prescriptions, traditional applications, and spice in food preparations. The phytochemical investigation conducted on crude extracts has been characterized and identified various classes of compounds, including coumarins, anthraquinone, terpenoids, alkaloid, benzodioxoles, phenolics, polyphenols, phenolic and polyphenols, fatty acids, phthalides and carotenoids. The extracts and compounds from the different parts of A. sowa showed diverse in vitro and in vivo biological activities including antioxidant, antiviral, antibacterial, analgesic and anti-inflammatory, Alzheimer associating neuromodulatory, cytotoxic, anticancer, antidiabetes, insecticidal and larvicidal.

CONCLUSION

A. sowa is a valuable medicinal plant which is especially used in food flavouring and culinary preparations. This review summarized the pertinent information on A. sowa and its traditional and culinary uses, as well as potential pharmacological properties of essential oils, extracts and isolated compounds. The traditional uses of A. sowa are supported by in vitro/vivo pharmacological studies; however, further investigation on A. sowa should be focused on isolation and identification of more active compounds and establish the links between the traditional uses and reported pharmacological activities with active compounds, as well as structure-activity relationship and in vivo mechanistic studies before integrated into the medicine. The toxicological report confirmed its safety. Nonetheless, pharmacokinetic evaluation tests to validate its bioavailability should be encouraged.

Biological Potential of Products Obtained from Palm Trees of the Genus Syagrus

Medicinal plants have been used for centuries by communities worldwide, as they have diverse biological properties and are effective against numerous diseases. The genus Syagrus stands out for its versatility and for so many activities presented by these palm trees, mainly due to its rich chemical and fatty acid compositions. The genus has antibacterial potential, has antibiofilm, antiparasitic, antioxidant, prebiotic, antiulcerogenic, anticholinesterase, and hypoglycemic activities, and can produce biodiesel, amid others. Among all species, Syagrus coronata and Syagrus romanzoffiana stand out, presenting the greatest number of activities and applications. The secondary metabolites obtained from these palm trees present high activity even in low concentrations and can be used against infections and chronic diseases. Furthermore, these plants have been used in some communities for years and have presented healing properties, especially in inflammatory processes. Therefore, the Syagrus genus proves to be promising, which shows a lot of therapeutic potential.

Phytochemical Profiling in Conjunction with In Vitro and In Silico Studies to Identify Human α-Amylase Inhibitors in Leucaena leucocephala (Lam.) De Wit for the Treatment of Diabetes Mellitus

Bioactive constituents from natural sources are of great interest as alternatives to synthetic compounds for the treatment of various diseases, including diabetes mellitus. In the present study, phytochemicals present in Leucaena leucocephala (Lam.) De Wit leaves were identified by gas chromatography-mass spectrometry and further examined by qualitative and quantitative methods. α-Amylase enzyme activity assays were performed and revealed that L. leucocephala (Lam.) De Wit leaf extract inhibited enzyme activity in a dose-dependent manner, with efficacy similar to that of the standard α-amylase inhibitor acarbose. To determine which phytochemicals were involved in α-amylase enzyme inhibition, in silico virtual screening of the absorption, distribution, metabolism, excretion, and toxicity properties was performed and pharmacophore dynamics were assessed. We identified hexadecenoic acid and oleic acid ((Z)-octadec-9-enoic acid) as α-amylase inhibitors. The binding stability of α-amylase to those two fatty acids was confirmed in silico by molecular docking and a molecular dynamics simulation performed for 100 ns. Together, our findings indicate that L. leucocephala (Lam.) De Wit-derived hexadecanoic acid and oleic acid are natural product-based antidiabetic compounds that can potentially be used to manage diabetes mellitus.

West meets east: open up a dialogue on phytomedicine

The desire to extend the wisdom of traditional health systems has motivated the trade of many phytomedicine on a global scale for centuries, especially some dietary herbs, making a great overlap exits between western and eastern phytomedicine. Despite the communication since ancient times, a key disconnect still exists in the dialog among western and eastern herbal researchers. There is very little systematic effort to tap into the friction and fusion of eastern and western wisdom in utilizing phytomedicine. In this review, we analyzed the similarities and differences of three representative phytomedicine, namely Rhodiola, seabuckthorn, and fenugreek, aiming to open up new horizons in developing novel health products by integrating the wisdom of the east and the west.

Synthesis of novel 5-(2,5-bis(2,2,2-trifluoroethoxy)phenyl)-1,3,4-oxadiazole-2-thiol derivatives as potential glucosidase inhibitors

BACKGROUND

A hybrid molecule of different biologically active substances can improve affinity and efficiency compared to a standard drug. Hence based on this fact, we predict that a combination of fluorine, oxadiazole, sulfur, etc., may enhance α-glucosidase inhibition activity compared to a standard drug.

METHODS

A series of novel 5-(2,5-bis(2,2,2-trifluoroethoxy)phenyl)-1,3,4-oxadiazole-2-thiol derivatives (2a-2i) were synthesized and characterized using spectroscopic techniques such as ¹HNMR and LC-MS. In order to evaluate its bioactivity, in vitro α-amylase and α-glycosidase inhibitory activity were performed. In vivo study was carried using a genetic model, Drosophila melanogaster, for assessing the antihyperglycemic effects.

RESULTS

The compounds 2a-2i demonstrated α-amylase inhibitory activity in the range of IC₅₀ = 40.00-80.00 μg/ml as compare to standard acarbose (IC₅₀ = 34.71 μg/ml). Compounds 2a-2i demonstrated α-glucosidase inhibitory activity in the range of IC₅₀ = 46.01-81.65 μg/ml as compared to standard acarbose (IC₅₀ = 34.72 μg/ml). Docking studies on a target protein, N-terminal subunit of human Maltase-glucoamylase (PDB:2QMJ) was carried and the compounds were found to dock into the active site of the enzyme (Fig. 1). The predicted binding energies of the compounds were calculated. The in vitro studies indicate that compounds 2b and 2g had better activity among the synthesized compounds. Whereas in vivo study indicates that 2b, 2g, and 2i could lower glucose levels in the Drosophila, but then 17-30% reduced capacity than acarbose and may be overcome by adjusting their dosage.

CONCLUSIONS

The in vitro and in vivo studies indicate that compounds 2b and 2g had better activity among the synthesized compounds. This study has recognized that compounds like 2b, 2g, and 2i may be considered potential candidates for further developing a novel class of antidiabetic agents.