Antiglycation Activity Research Articles

Attenuation of methylglyoxal-induced glycation and cellular dysfunction in wound healing by Centella cordifolia.

Current pre-clinical evidences of Centella focus on its pharmacological effects on normal wound healing but there are limited studies on the bioactivity of Centella in cellular dysfunction associated with diabetic wounds. Hence we planned to examine the potential of Centella cordifolia in inhibiting methylglyoxal (MGO)-induced extracellular matrix (ECM) glycation and promoting the related cellular functions. A Cell-ECM adhesion assay examined the ECM glycation induced by MGO. Different cell types that contribute to the healing process (fibroblasts, keratinocytes and endothelial cells) were evaluated for their ability to adhere to the glycated ECM. Methanolic extract of Centella species was prepared and partitioned to yield different solvent fractions which were further analysed by high performance liquid chromatography equipped with photodiode array detector (HPLC-PDA) method. Based on the antioxidant [2,2-diphenyl-1-picrylhydrazyl (DPPH) assay] screening, anti-glycation activity and total phenolic content (TPC) of the different Centella species and fractions, the ethyl acetate fraction of C. cordifolia was selected for further investigating its ability to inhibit MGO-induced ECM glycation and promote cellular distribution and adhesion. Out of the three Centella species (C. asiatica, C. cordifolia and C. erecta), the methanolic extract of C. cordifolia showed maximum inhibition of Advanced glycation end products (AGE) fluorescence (20.20 ± 4.69 %, 25.00 ± 3.58 % and 16.18 ± 1.40 %, respectively). Its ethyl acetate fraction was enriched with phenolic compounds (3.91 ± 0.12 mg CAE/μg fraction) and showed strong antioxidant (59.95 ± 7.18 μM TE/μg fraction) and antiglycation activities. Improvement of cells spreading and adhesion of endothelial cells, fibroblasts and keratinocytes was observed for ethyl acetate treated MGO-glycated extracellular matrix. Significant reduction in attachment capacity of EA.hy926 cells seeded on MGO-glycated fibronectin (41.2%) and attachment reduction of NIH3t3 and HaCaT cells seeded on MGO-glycated collagen (33.7% and 24.1%, respectively) were observed. Our findings demonstrate that ethyl acetate fraction of C. cordifolia was effective in attenuating MGO-induced glycation and cellular dysfunction in the in-vitro wound healing models suggesting that C. cordifolia could be a potential candidate for diabetic wound healing. It could be subjected for further isolation of new phytoconstituents having potential diabetic wound healing properties.

Polysaccharides from dandelion (Taraxacum mongolicum) leaves: Insights into innovative drying techniques on their structural characteristics and biological activities

The aim of this study was to well understand the impacts of innovative drying techniques (radio frequency drying and microwave drying) and traditional drying techniques (vacuum drying, freezing drying, and hot air drying) on the structural characteristics and bioactivities of polysaccharides from dandelion leaves (DLPs). Five different DLPs were obtained from dandelion leaves dried by abovementioned drying techniques. Results showed that the structural characteristics and bioactivities of DLPs varied with different drying techniques. The molecular weights, apparent viscosities, molar ratios of constituent monosaccharide, contents of uronic acids, and contents of bonded polyphenolics in DLPs obtained by different drying techniques had noticeable variations, while the types of constituent monosaccharides and the major glycosidic linkages in DLPs were similar. In addition, results showed that DLPs, especially DLP-RF obtained by the radio frequency drying, exhibited remarkable antioxidant activities (ABTS, DPPH, and NO radical scavenging activities), excellent in vitro antiglycation activity, and obvious in vitro inhibitory activity on α-glucosidase. Results from this study suggest that the radio frequency drying can be used as a potential drying technique before extracting DLPs for applications in the functional food and medicine industries.

Isolation of new secondary metabolites from the liana Landolphia lucida K. Schum. (Apocynaceae)

Abstract A new pentacyclic triterpene 3-O-β-(E)-(4-O-acetylferuloyl)-lupeol (1) possessing an unusual (E)-acetylferuloyl moiety at C-3 and a new bicoumarin 7,7′-dimethoxy-6,6′-dicoumarinyl ether (2) were isolated from the liana Landolphia lucida K. Schum, along with fourteen previously known compounds 3-16, where methandriol dipropionate (3) and 2,3-bis-(4-hydroxy-3-methoxy-benzyl)-dimethyl- succinate (5) were obtained for the first time from natural sources. The structures of the new compounds were established on the basis of extensive 1D and 2D NMR spectroscopy, and HRMS data analyses. The absolute configuration of 1 was determined by circular dichroism (CD) spectroscopy. Furthermore, compounds 1 and 2 had exhibited a significant antibacterial activity against Escherichia coli (ATCC 25922) with MIC values of 2.3 μM and 4.6 μM, respectively; while compounds 4 and 5 showed antiglycation and α-glucosidase inhibitory activities.

Prediction of Antiglycation Activity by Calculating the Energies of Frontier Molecular Orbitals for New 4-Hydroxy-1,4-Dihydroazolo[5,1-c]-1,2,4-Triazines Used as an Example

Protein glycation and the formation of advanced glycation end products (AGEs) play an important role in the pathogenesis of diabetes mellitus (DM) complications, neurodegenerations, and age-related diseases. A model to predict antiglycation activity can reduce the costs and increase the productivity and quality of preclinical screening studies of new compounds. Azolo[5,1-c][1,2,4]triazines and azolo[1,5-a]pyrimidines are well known as biologically active compounds, which additionally have antiglycation properties. A number of 4-hydroxy-4H-azolo-1,4-dihydro[5.1-c]-1,2,4-triazines were selected for designing a prediction model. Azolotriazine derivatives were found to exert an antiglycation effect, inhibiting glycation of bovine serum albumin (BSA) with glucose and specific END fluorescence with equal or greater efficiency as compared with aminoguanidine. The activity range at 1000 μM was estimated at 23.0–71.6% for variously substituted derivatives (30.3 ± 1.2% for aminoguanidine). The highest activity was observed for 4-hydroxy-3-cyano-1,4-dihydro-1,2,4-triazolo[5.1-c]1,2,4-triazine. In all but one compound (aminoguanidine), antiglycation activity correlated with the energy difference ∆(HOMO – LUMO) between the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO); the difference was established by a PM3 semiempirical method. Artificial neural network modeling was used to develop a mathematical model that describes the dependence of antiglycation activity on the calculated energies. The ELUMO and ∆(HOMO – LUMO) energies were found to make the largest contribution to the activity. The model can be used to predict antiglycation activity.

Synthesis, structural, spectral and biological evaluation of metals endowed 1,2,4-triazole

Biologically active triazole Schiff base ligand 2,4-dichloro-6-[(1H-1,2,4-triazol-3-ylimino)methyl]phenol (A) has been synthesized by the condensation reaction of an equimolar amount of 1H-1,2,4-triazole-3-amine and 3,5-dichlorosalicylaldehyde and then it coordinated with salts of metals [VO(IV), Fe(II), Co(II), Ni(II), Cu(II) and Zn(II)] in 2:1 molar ratio to derive a series of transition metal chelates (1)-(6). All the compounds were characterized by various physical, spectral, analytical techniques and elemental analysis. Spectral characterization and magnetic moment data of complexes revealed square pyramidal geometry for vanadium complex and octahedral for remaining (2)-(6) complexes. Quantum chemical calculation has been carried out to explore optimized geometry and electronic structure of the ligand. Density functional theory (DFT) with B3LYP/6-311+g(d,p) method was performed to determine vibrational bands, frontier molecular orbitals (FMOs) and natural bond analysis (NBO) of the ligand. NBO analysis showed that the ligand bears higher molecular stability because of hyper conjugate interactions. Computational study results revealed that there was a close interaction of theoretical and experimental spectroscopic data. Global reactivity descriptors calculated by the energies of FMOs, indicated ligand to be bioactive. The synthesized compounds were studied for antibacterial, antifungal, antioxidant and antiglycation activity and the results revealed that ligand has remarkable activity which considerably increased upon chelation.
 
 KEY WORDS: Triazole ligand, Transition metal chelates, Antibacterial, Antifungal, Antioxidant, Computational study
 
 Bull. Chem. Soc. Ethiop. 2020, 34(2), 335-351
 DOI: https://dx.doi.org/10.4314/bcse.v34i2.11

Comparative evaluation of chemical composition and biological activities of tropical fruits consumed in Manaus, central Amazonia, Brazil

Fruits are widely recognized as sources of biologically active metabolites, such as antioxidant compounds. In this context, fruits commonly consumed in the central Amazonia, especially in its biggest metropolis (Manaus – AM/Brazil), are attractive as potential sources of antioxidant compounds related to biological activities. Most of such fruits are still poorly studied and/or remain unknown outside the Amazon region. Therefore, this study aims to investigate nine fruits (abiu, cubiu, biribá, breadfruit, genipap, peach palm, murici, soursop, and umari) regarding their chemical composition (fixed and volatile), reducing capacity, antioxidant activity, enzyme inhibition, and cytotoxicity. Determination of small organic acids, hydroxycinnamic acids, flavan-3-ols and flavonoid aglycones was done by HPLC-MS/MS, whereas determination of volatile organic compounds (VOCs) was done by HS-SPME/GC–MS. Reducing capacity was determined by the Folin–Ciocalteu method, and antioxidant activities were evaluated by DPPH, ABTS, and H-ORACFL assays. In vitro activities regarding inhibition of enzymes were tested for α-glucosidase, lipase, and α-amylase, and anti-glycation activities were evaluated for methylglyoxal and fructose. Cytotoxicity of fruit extracts was evaluated by cell viability of human fibroblast cell line (MRC-5). A total of 16 antioxidant compounds and 139 VOCs were determined, whose profiles were unique for each studied fruit. Total phenolic contents as well as antioxidant activities found herein were similar or even higher than those reported for several traditional fruits. Some of fruit extracts were able to inhibit α-glucosidase and glycation in methylglyoxal and fructose models, whereas none of them was active for lipase and α-amylase. All of the fruit extracts showed to be non-cytotoxic to MRC-5 cell line.

Development and validation of HPTLC method for identification and quantification of sterols from leaves of Erythroxylum monogynum Roxb. and in vitro evaluation of anti-oxidant and anti-glycation activities

The petroleum ether extract from leaves of Erythroxylum monogynum when subjected to phytochemical analysis and chromatographic purification, resulted in the isolation of two new sterols namely 4-methyl ergosta-7, 23‑dien‑3β-ol and 4-methyl ergosta-7, 24 (28)‑dien‑3β-ol. Their structure was elucidated by NMR and Mass Spectrometry. The two sterols were separated on a silica gel 60F254 HPTLC plates impregnated with AgNO3 using dichloromethane: methanol (9:1 v/v) as a mobile phase. Upon densitometric scanning at 254 nm in a reflectance mode, the two sterols separated as sharp and compact bands with Rf of 0.47±0.02 and 0.52±0.01 respectively for 4-methyl ergosta-7, 23‑dien‑3β-ol and 4-methyl ergosta-7, 24 (28)‑dien‑3β-ol. Linear regression and calibration plots constructed (n = 6) showed excellent linearity at 100–500 ng per spot with a correlation coefficient, r = 0.9979±0.0004 and 0.9974±0.0007 for 4-methyl ergosta-7,23‑dien‑3β-ol and 4-methyl ergosta-7,24 (28)‑dien‑3β-ol, respectively. The Limits of detection and quantification were found to be 21.07 ng and 57.23 ng/band for 4-methyl ergosta-7,23‑dien‑3β-ol and 25.18 ng and 63.86 ng/band for 4-methyl ergosta-7,24 (28)‑dien‑3β-ol, respectively. Both the sterols demonstrated good anti-oxidant and anti-glycation activities where, the IC50 values obtained were comparable with the positive control compounds, ascorbic acid and aminoguanidine. The 4-methyl ergosta-7,23‑dien‑3β-ol displayed 100% anti-oxidant activity at 100 µg/ml for both DPPH and H2O2 scavenging assays. In addition, both the sterols presented more than 90% inhibition of Advanced Glycation End products at 100 µg/ml concentration. The results obtained are remarkable indicating that these plant extracts could serve as a natural alternative to the conventional oral hypoglycemic molecules.

Ultrafiltration isolation, physicochemical characterization, and antidiabetic activities analysis of polysaccharides from green tea, oolong tea, and black tea.

Both fermentation degree and preparation method of polysaccharides could influence the bioactivity of tea polysaccharides. The aim of this study was to compare the physicochemical characterization and biological activities of the polysaccharides isolated by ultrafiltration method from three kinds of tea (green tea, oolong tea, and black tea). The bioactivities of tea polysaccharide fractions were compared from four aspects, including antioxidant activities, antiglycation activities, α-glucosidase inhibitory capability, and hypoglycemic effects on L6 myotubes. Results showed that six polysaccharides (GTPS1, GTPS2, OTPS1, OTPS2, BTPS1, and BTPS2) had different contents of neutral sugar and uronic acid, and they showed different morphologies. Six polysaccharides were composed of the seven monosaccharides with different molar ratios. BTPS1 exhibited the highest DPPH scavenging activity and hydroxyl radical scavenging activity (P < 0.05), and BTPS1 also showed the strongest antiglycation inhibitory effects (P < 0.05). BTPS1 and BTPS2 showed strong inhibitory capacity on α-glucosidase and hypoglycemic effects in L6 skeletal muscle cells. The result suggested that the degree of fermentation of tea could improve their bioactivities (BTPS > OTPS >GTPS), and TPS1 with smaller molecular weight distribution showed higher bioactivities than TPS2. This study can provide a scientific foundation for the application of tea polysaccharides and related functional products.

Identification, protein antiglycation, antioxidant, antiproliferative, and molecular docking of novel bioactive peptides produced from hydrolysis of Lens culinaris.

Bioactive peptides produced from natural sources are considered as strategic target for drug discovery. Hyperglycemia caused protein glycation alters the structure of many tissues that impairs their functions and lead complications diseases in human body. This study investigated the bioactive peptides produced from red and brown Lens culinaris that might inhibit protein glycation to prevent diabetic complications. In this study, red and brown Lens culinaris protein hydrolysates were prepared by tryptic digestion, using an enzyme/substrate ratio of 1:20 (g/g), at 37°C, 12hr then peptide fractions <3kDa were filtered by using ultrafiltration membranes. Protective ability against protein glycation, DPPH radical scavenging, and anti-proliferative activities (on HepG2, MCF-7, and PC3 cell lines) of peptide fractions were assayed in vitro. Results showed that glycation was inhibited by peptides from 28.1% to 68.3% in different test model. PC3 cell line was more sensitive to the peptides which showed strong anticancer activity with lower IC50 (0.96mg/ml). Peptide fractions were sequenced by HPLC-MS-MS. Twenty eight novel peptides sequences was identified. In silico study, two peptides could be developed as a potential bioactive peptides exhibited antiglycation, antioxidant, and antiproliferative activities. PRACTICAL APPLICATIONS: Peptides are becoming an emerging source of medications with the development of new technologies. We have selected Lens Culinaris as one of the rich sources of proteins to explore novel bioactive peptides encapsulated in its seeds. Peptides fractions demonstrated protective ability against protein glycation, strong antioxidant potential, and promising antiproliferative activity. We have identified 28 novel peptides and molecular docking study revealed that some peptides showed strong binding potential to insulin receptor and ACE. Thus, these peptides might be used to manage diabetes complication as well as COVID-19 disease due to their interaction with ACE. However, those peptides needs to be further studied as a potential new drug.

Adsorption and desorption characteristics of a phenolic compound from Ecklonia cava on macroporous resin

This study aimed to develop efficient adsorption and desorption processes to purify phenolic compounds from Ecklonia cava. We compared the adsorption and desorption properties of five resins. HP2MG showed the highest adsorption and desorption capacities and adsorption rate; hence, it was selected for phenolic compound purification. Adsorption isotherm parameters indicated favorable adsorption between HP2MG and phenolic compounds. Thermodynamic parameters showed that the absorption process physically proceeded. In the dynamic adsorption process, adsorption property was assessed based on bed length (4–10 cm) and flow rate (1.64–3.27 mL/min). The breakthrough point increased with increased bed length and decreased adsorption flow rate. However, the high desorption flow rate shortened the processing time. The phenolic contents, anti-glycation activity and antioxidant activity of the extract were measured before and after purification. The dieckol and phlorofucofuroeckol-A increased three times after purification. The purified extract showed higher anti-glycation and antioxidant activities than the extract.

A New Insight into Meloxicam: Assessment of Antioxidant and Anti-Glycating Activity in In Vitro Studies.

Meloxicam is a non-steroidal anti-inflammatory drug, which has a preferential inhibitory effect to cyclooxyganase-2 (COX-2). Although the drug inhibits prostaglandin synthesis, the exact mechanism of meloxicam is still unknown. This is the first study to assess the effect of meloxicam on protein glyco-oxidation as well as antioxidant activity. For this purpose, we used an in vitro model of oxidized bovine serum albumin (BSA). Glucose, fructose, ribose, glyoxal and methylglyoxal were used as glycating agents, while chloramine T was used as an oxidant. We evaluated the antioxidant properties of albumin (2,2-di-phenyl-1-picrylhydrazyl radical scavenging capacity, total antioxidant capacity and ferric reducing antioxidant power), the intensity of protein glycation (Amadori products, advanced glycation end products) and glyco-oxidation (dityrosine, kynurenine, N-formylkynurenine, tryptophan and amyloid-β) as well as the content of protein oxidation products (advanced oxidation protein products, carbonyl groups and thiol groups). We have demonstrated that meloxicam enhances the antioxidant properties of albumin and prevents the protein oxidation and glycation under the influence of various factors such as sugars, aldehydes and oxidants. Importantly, the antioxidant and anti-glycating activity is similar to that of routinely used antioxidants such as captopril, Trolox, reduced glutathione and lipoic acid as well as protein glycation inhibitors (aminoguanidine). Pleiotropic action of meloxicam may increase the effectiveness of anti-inflammatory treatment in diseases with oxidative stress etiology.

2-Mercapto Benzothiazole Derivatives: As Potential Leads for the Diabetic Management.

Results of our previous studies on antiglycation activity, and the noncytotoxicity of 2-mercapto benzothiazoles, encouraged us to further widen our investigation towards the identification of leads against diabetes mellitus. 33 derivatives of 2-mercapto benzothiazoles 1-33 were evaluated for in vitro α- glucosidase inhibitory activity. Mode of inhibition was deduced by kinetic studies. To predict the interactions of 2-mercapto benzothiazole derivatives 1-33 with the binding pocket of α-glucosidase enzyme, molecular docking studies were performed on the selected inhibitors. Compounds 2-4, 6-7, 9-26, 28 and 30 showed many folds potent α-glucosidase inhibitory activity in the range of IC50 = 31.21-208.63 μM, as compared to the standard drug acarbose (IC50 = 875.75 ± 2.08 μM). It was important to note that except derivative 28, all other derivatives were also found previously to have antiglycating potential in the range of IC50 = 187.12-707.21 μM. A number of compounds were identified as dual nature as antiglycating agent and α- glucosidase inhibitors. These compounds may serve as potential lead candidates for the management of diabetes mellitus.

Pharmaceutical Potential and Phenolics Profiling of Leaves and Bark of Calotropis Procera in Relation to Extraction Solvents

This study appraises pharmaceutical potential and phenolics profiling of various solvent extracts gained from bark and leaves of Calotropis procera plant. The extracts were obtained using various solvents including CH3OH, C4H8O2, CHCl3 (50 and 100% for each) and H2O. The extracts were evaluated for antioxidant potential, antibacterial, antianti-glycation and anti-inflammatory activities. The yield of extracts ranged from 5.61 to 48.16% of dry weight (DW) for different extraction solvents. The highest percentage extract yield was obtained with 100% CH3OH from leaves. Various solvent extracts from C. procera leaves and bark exhibited considerable total phenolic content (20.41 to 100.18 GAE mg/g DW and total flavonoid content (IC50 18.33 to 92.92 CE mg/g DW), radical scavenging activity (1.03 to 7.42 mg/mL) and reducing power (EC50 525.65 to 1157.74 mg/mL). The tested extracts showed notable antibacterial potential against bacterial strains such as Klebsiella pneumonia, Pseudomonas aeruginosa, Bacillus subtilis, and Escherichia coli. The maximum antioxidant and antibacterial activities were exhibited by methanol extracts from both tested parts of C. procera plant. However, the anti-inflammatory activity (45.45% inhibition) was observed to be higher for 50% chloroform extract from the leaves. HPLC analysis established that the leaves and bark of C. procera contained considerable amounts of natural antioxidants such as sinapic acid (17.3 ± 2.11 to 9586.44 ± 0.78 mg kg-1), vanillic acid (9.43 ± 0.21 to 5051.7 ± 18.47 mg kg-1) and protocatechuic acid (2.46 ± 0.40 to 139.05 ± 1.37 mg kg-1). All extracts from the tested materials did not exhibit significant anti-glycation activity. Generally, the extracts from leaves of C. procera offered higher levels of phenolic acids and biological activities than the bark extracts.

Antioxidative and Antiglycative Properties of Mycosporine-Like Amino Acids-Containing Aqueous Extracts Derived from Edible Terrestrial Cyanobacteria.

The terrestrial filamentous cyanobacterium, Nostoc commune, has been used as a food source in many countries, especially countries in Asia. In this study, N. commune-derived aqueous extracts were evaluated with regard to their antioxidative and antiglycative properties. The antioxidative activity was significantly higher in N. commune colonies isolated from the field than in extracts from colonies cultured in the laboratory. The antioxidative compound content of extracts, including phenolic compounds and phycobiliproteins, was correlated with their antioxidative power. In addition, two mycosporine-like amino acids (MAAs), specifically detected in colonies isolated from the field, were purified. In addition to assessing their antioxidative properties, the antiglycative activity of these MAAs was also assessed. Their inhibitory effects on glycation-dependent protein cross-linking might contribute to the antiglycative power of the extract prepared from field colonies. Taken together, the results from this study revealed that N. commune may have beneficial properties for functional food applications, both by preventing oxidative stress and suppressing the formation of advanced glycation end-products.

The effects of fermentation with lactic acid bacteria on the antioxidant and anti-glycation properties of edible cyanobacteria and microalgae

Cyanobacteria and microalgae-derived food supplements have gained attention in recent times, owing to their antioxidant, hypolipidemic, and anti-obesity effects. In the present study, we analysed the antioxidant and anti-glycation activities of 12 aqueous extract solutions (AESs) of 10 species of cyanobacteria and microalgae. The AESs of the microalgae Dunaliella tertiolecta and Pleurochrysis carterae showed strong ferric-reducing powers, superoxide anion (O2−) radical scavenging capacity, and anti-glycation activity in a bovine serum albumin (BSA)-fructose model. Wild Nostoc commune (cyanobacteria) and sake lees cultured Euglena sp. (microalga) could be fermented by Lactococcus lactis subsp. lactis Uruma-SU1, whereas normal cultured N. commune and Euglena could not. The O2− radical-scavenging capacity and anti-glycation activity in the BSA-methylglyoxal model of the fermented wild N. commune and sake lees cultured Euglena samples were higher than those of the other samples. As advanced glycation end products and reactive oxygen species induce age-related diseases, our study illustrates the health-promoting properties of D. tertiolecta and P. carterae and lactic acid bacteria-fermented wild N. commune and sake lees cultured Euglena sp.; moreover, it communicates their importance as nutritional food materials.

The Effect of UV Irradiation on Vitamin D2 Content and Antioxidant and Antiglycation Activities of Mushrooms.

Mushroom irradiation has been considered a sustainable process to generate high amounts of vitamin D2 due to the role of this vitamin for human health and of the global concerns regarding its deficient or inadequate intake. Mushrooms are also receiving increasing interest due to their nutritional and medicinal properties. However, there is still a knowledge gap regarding the effect of UV irradiation on mushroom bioactive compounds. In this study, two of the most cultivated mushroom species worldwide, Agaricus bisporus and Pleurotus ostreatus, were irradiated with UV-B, and the effect of processing was investigated on the contents of vitamin D2 as well as on antioxidant and antiglycation activities. UV irradiation increased vitamin D2 up to 57 µg/g d.w, which is an adequate level for the fortification of a number of target foods. UV irradiation decreased the antioxidant activity when measured by the Folin–Ciocalteu reagent, the 2,2-diphenyl-1-(2,4,6 trinitrophenyl) hydrazyl radical assay and the ferric ion-reducing antioxidant power assay, but did not decrease the mushroom’s ability to inhibit glycation of a target protein. These results open up a new area of investigation aimed at selecting mushroom species with high nutraceutical benefits for irradiation in order to maintain their potential properties to inhibit oxidative and glycation processes responsible for human diseases.

Caracterización biofuncional de extractos de raíz de ginseng rojo, blanco y negro (Panax ginseng Meyer)

An organized biofunctional characterization of red, black, and white ginseng root extracts and fractions was performed. To assess antioxidant, antiglycation, enzyme inhibitory, antiamnestic, cytotoxic, thrombolytic, antibiofilm potentials in roots of three Panax ginseng preparations (red, black, white), powdered material was extracted and fractionated into different solvents. Antioxidant activity, phenolic and flavonoids contents were assessed by using free radical scavenging, Folin–Ciocalteu reagent and aluminum chloride colorimetric assays. Antiglycation and enzyme (alpha amylase, alpha glucosidase and acetylcholinesterse) inhibition activities were tested by prescribed methods along with cytotoxic (antihemolytic profile), thrombolytic activity, and biofilm growth inhibition assays. Red and black ginseng indicated maximum phenolic contents (37.26 ± 1.563 g GAE) and flavonoid contents (149.4 ± 2.032 g CE) respectively. The DPPH scavenging ability (62.84%) of red ginseng was higher than black and white ginseng. Significant antidiabetic activities were exhibited by black and white ginseng. The highest antihemolytic (71.2%) and thrombolytic (87%) actions were shown by black and red ginseng respectively. Red and white ginseng maximally inhibited the growth of Pasteurella multocida while in the case of Staphylococcus aureus, red ginseng showed optimum antibiofilm activity. The present study demonstrates that all three preparations of P. ginseng have effective yet variable functional characteristics that warrant further exploration.

Isolation of Antidiabetic Withanolides from Withania coagulans Dunal and Their In Vitro and In Silico Validation.

Withania coagulans (W. coagulans) is well-known in herbal medicinal systems for its high biological potential. Different parts of the plant are used against insomnia, liver complications, asthma, and biliousness, as well as it is reported to be sedative, emetic, diuretic, antidiabetic antimicrobial, anti-inflammatory, antitumor, hepatoprotective, antihyperglycemic, cardiovascular, immuno-suppressive and central nervous system depressant. Withanolides present in W. coagulans have attracted an immense interest in the scientific field due to their diverse therapeutic applications. The current study deals with chemical and biological evaluation of chloroform, and n-butanol fractions of W. coagulans. The activity-guided fractionation of both extracts via multiple chromatographic steps and structure elucidation of pure isolates using spectroscopies (NMR, mass spectrometry, FTIR and UV-Vis) led to the identification of a new withanolide glycoside, withacogulanoside-B (1) from n-butanol extract and five known withanolides from chloroform extract [withanolid J (2), coagulin E (3), withaperuvin C (4), 27-hydroxywithanolide I (5), and ajugin E (6)]. Among the tested compounds, compound 5 was the most potent α-glucosidase inhibitor with IC50 = 66.7 ± 3.6 µM, followed by compound 4 (IC50: 407 ± 4.5 µM) and compound 2 (IC50: 683 ± 0.94 µM), while no antiglycation activity was observed with the six isolated compounds. Molecular docking was used to predict the binding potential and binding site interactions of these compounds as α-glucosidase inhibitors. Consequently, this study provides basis to discover specific antidiabetic compounds from W. coagulans.

Review of Chemical, Pharmacological, Biological Activities of Isatin and Its Derivatives – Part-2 (2002 To 2020)

: Isatin is a naturally occurring substance identified in humans, animals, plants and coal tar. Isatin derivatives are reported to possess a wide range of activites. This review is in continuation of “Part-1 (1877-2002)” review published by our team. This review encompasses the most signigicant reports published during 2002 to 2020 on the biological &amp; pharmacological activites of isatin and its derivatives. The review includes the various synthetic reactions of isatin and activites reported. The pharmacological and biological activites reported were antimicrobial, antineoplastic &amp; related activities; analgesic, anti-inflammatory, anticonvulsant, antioxidant, activity against veterinary pathogen, effects on cardiac &amp; vascular smooth muscles; transthyretin fibrillogenesis inhibitor and antiglycation activity of isatin compounds.

Flavonoids Identification and Pancreatic Beta-Cell Protective Effect of Lotus Seedpod.

Oxidative stress is highly associated with the development of diabetes mellitus (DM), especially pancreatic beta-cell injury. Flavonoids derived from plants have caused important attention in the prevention or treatment of DM. Lotus seedpod belongs to a traditional Chinese herbal medicine and has been indicated to possess antioxidant, anti-age, anti-glycative, and hepatoprotective activities. The purpose of this study was to demonstrate the pancreatic beta-cell protective effects of lotus seedpod aqueous extracts (LSE) against oxidative injury. According to HPLC/ESI-MS-MS method, LSE was confirmed to have flavonoids derivatives, especially quercetin-3-glucuronide (Q3G). In vitro, LSE dose-dependently improved the survival and function of rat pancreatic beta-cells (RIN-m5F) from hydrogen peroxide (H2O2)-mediated loss of cell viability, impairment of insulin secretion, and promotion of oxidative stress. LSE showed potential in decreasing the H2O2-induced occurrence of apoptosis. In addition, H2O2-triggered acidic vesicular organelle formation and microtubule-associated protein light chain 3 (LC3)-II upregulation, markers of autophagy, were increased by LSE. Molecular data explored that antiapoptotic and autophagic effects of LSE, comparable to that of Q3G, might receptively be mediated via phospho-Bcl-2-associated death promoter (p-Bad)/B-cell lymphoma 2 (Bcl-2) and class III phosphatidylinositol-3 kinase (PI3K)/LC3-II signal pathway. In vivo, LSE improved the DM symptoms and pancreatic cell injury better than metformin, a drug that is routinely prescribed to treat DM. These data implied that LSE induces the autophagic signaling, leading to protect beta-cells from oxidative stress-related apoptosis and injury.