Standard Ascorbic Acid Research Articles

GC-MS and HPTLC bioautography-based phytochemical profiling and evaluation of biological activity Neptunia prostrata Linn whole plant and leaves

This work used experimental methods to evaluate the chemical composition of GC-MS, HPTLC-based bioautographaphy, antioxidant, anti-diabetic, and protein denaturation properties of the Neptunia prostrata Linn (family: Mimosaceae) whole plant and leaves. Three methods, namely DPPH, metal chelating, and reducing power assays, were used to estimate the antioxidant effects. In addition, α-amylase, a carbohydrate-hydrolyzing enzyme, was targeted to test the anti-diabetic activity. The protein denaturation assay was used to evaluate the anti-inflammatory activity of the plant. GC-MS, an important analytical tool, was performed to identify bioactive compounds of medicinal plants used in pharmaceutical industries. Biochemical derivatization HPTLC-based bioautography with DPPH was executed to identify antioxidant agents from N. prostrata. The validated HPTLC method was used to quantify identified antioxidant agents. The stability of compounds, preparation of calibration curves, linearity, range, precision, limit of detection, limit of quantification, robustness, and accuracy are examined to develop a robust method. Higher total phenolic content (TPC) content was observed in N. prostrata hydroalcoholic extract of the whole plant (81.12 ± 4.19 mg GAE/g) and methanolic extract of leaves (105.16 ± 3.11 mg GAE/g). Methanolic extract of N. prostrata leaves showed significantly high antioxidant potential for all DPPH (IC50:28.05 ± 1.78 µg/mL), metal chelating (IC50:1598 ± 23.51 µg/mL), and reducing power assay compared to standard ascorbic acid (DPPH assay: IC50:24.14 ± 2.34 µg/mL and metal chelating: IC50:1301.16 ± 6.14 µg/mL). N. prostrata aqueous extract of the whole plant (IC50:179.47 ± 10.59 µg/mL) and leaves (IC50:130.86 ± 3.58 µg/mL) showed significantly high α-amylase inhibitory activity as compared to standard acarbose (IC50:148.62 ± 7.84 µg/mL). Methanolic extract of whole plants (IC50:131.46 ± 11.81 µg/mL) and chloroform extract of leaves (IC50:122.61 ± 8.19 µg/mL) exhibited strong anti-inflammatory activity as compared to standard acetylsalicylic acid (IC50:117.77 ± 4.95 µg/mL). GC-MS analysis revealed the presence of several bioactive compounds, where 2-cyclopenten-1-one, 2-hydroxy showed the most abundant bioactive compounds in the plant with 17.01%. HPTLC-bioautography identified three phenolic acids (chlorogenic acid, gallic acid, and 4-hydroxybenzoic acid) and one flavonoid (naringenin), further quantified with the validated HPTLC method. These findings propose that N. prostrata has therapeutic potential for treating diseases related to oxidative damage, diabetes, and inflammation, which may be due to the presence of bioactive compounds.

Antioxidant and anticholinesterase properties of Echinometra mathaei and Ophiocoma erinaceus venoms from the Persian Gulf.

Introduction: The Persian Gulf is home to a diverse range of marine life, including various species of fish, crustaceans, mollusks, and echinoderms. This study investigates the potential therapeutic properties of venoms from echinoderms in the Persian Gulf, specifically their ability to inhibit cholinesterases (Acetylcholinesterase and butyrylcholinesterase) and act as antioxidants. Methods: Four venoms from two echinoderm species, including the spine, gonad, and coelomic fluids of sea urchins, as well as brittle star venoms, were analyzed using various methods, including LD50 determination, protein analysis, antioxidant assays, GC-MS for secondary metabolite identification, and molecular docking simulations. Results and discussion: The study's results revealed the LD50 of the samples as follows: 2.231 ± 0.09, 1.03 ± 0.05, 1.12 ± 0.13, and 6.04 ± 0.13mg/mL, respectively. Additionally, the protein levels were 44.037 ± 0.002, 74.223 ± 0.025, 469.97 ± 0.02, and 104.407 ± 0.025μg/mL, respectively. SDS-PAGE and total protein studies indicated that at least part of the venom was proteinaceous. Furthermore, the study found that the brittle star samples exhibited significantly higher antioxidant activity compared to other samples, including the standard ascorbic acid, at all tested concentrations. GC-MS analysis identified 12, 23, 21, and 25 compounds in the samples, respectively. These compounds had distinct chemical and bioactive structures, including alkaloids, terpenes, and steroids. Conclusion: These venoms displayed strong cholinesterase inhibitory and antioxidant activities, likely attributed to their protein content and the presence of alkaloids, terpenes, and steroids. Notably, the alkaloid compound C 7 was identified as a promising candidate for further research in Alzheimer's disease therapy. In conclusion, echinoderms in the Persian Gulf may hold significant potential for discovering novel therapeutic agents.

In Vitro Antioxidant and Antidiabetic properties of leaves aqueous extract of Sonchus maritimus

One of the most serious health issues facing worldwide today is diabetes mellitus. Although they have inevitable adverse effects, conventional antidiabetic medications are effective. However, plants might also provide an alternate source of anti-diabetic chemicals. This study was focused on determining the antioxidant activities of the leaves aqueous extract of Sonchus maritimus using 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging activity and ferric reducing ability assay power (FRAP), as well as its antidiabetic activities, which were performed using different protocols, including alpha-amylase inhibitory properties, glucose uptake by yeast cell’s ability, and glucose adsorption capacity. It was noted that S. maritimum extract exhibited moderate activities to scavenge the free radical DPPH and to reduce ferric iron to ferrous iron compared to standard (ascorbic acid). However, the aqueous extract of S. maritimus showed better alpha-amylase inhibitory activity compared to acarbose. It also showed good adsorption strength for binding to glucose molecules. Moreover, the extract showed excellent improvement in glucose uptake by yeast cells at different glucose concentrations in the medium compared to metformin. In conclusion, the aqueous extract of S. maritimus leaves is a promising source of potential antidiabetic compounds that can help prevent diabetes complications and alleviate associated oxidative stress.

Discovery of novel 1,2,4-triazole tethered β-hydroxy sulfides as bacterial tyrosinase inhibitors: synthesis and biophysical evaluation through in vitro and in silico approaches.

In this study, a series of 1,2,4-triazole-tethered β-hydroxy sulfide scaffolds 11a-h was synthesized in good to remarkable yields (69-90%) through the thiolysis of oxiranes by the thiols in aqueous basic catalytic conditions. The synthesized 1,2,4-triazole-tethered β-hydroxy sulfides were screened against bacterial tyrosinase enzyme, and Gram-positive and Gram-negative bacterial cultures i.e., (S. aureus) Staphylococcus aureus & (E. coli) Escherichia coli. Among the synthesized derivatives, the molecules 11a (IC50 = 7.67 ± 1.00 μM), 11c (IC50 = 4.52 ± 0.09 μM), 11d (IC50 = 6.60 ± 1.25 μM), and 11f (IC50 = 5.93 ± 0.50 μM) displayed the better tyrosinase inhibitory activity in comparison to reference drugs ascorbic acid (IC50 = 11.5 ± 1.00 μM) and kojic acid (IC50 = 30.34 ± 0.75 μM). The molecule benzofuran-triazol-propan-2-ol 11c proved to be the most potent bacterial tyrosinase inhibitory agent with a minimum IC50 of 4.52 ± 0.09 μM, as compared to other synthesized counterparts and both standards (kojic acid and ascorbic acid). The compound diphenyl-triazol-propan-2-ol 11a and benzofuran-triazole-propan-2-ol 11c showed comparable anti-bacterial chemotherapeutic efficacy with minimum inhibitory concentrations (MIC = 2.0 ± 2.25 mg mL-1 and 2.5 ± 0.00 mg mL-1, respectively) against S. aureus bacterial strain in comparison with standard antibiotic penicillin (MIC = 2.2 ± 1.15 mg mL-1). Furthermore, among the synthesized derivatives, only compound 11c demonstrated better anti-bacterial activity (MIC = 10 ± 0.40 mg mL-1) against E. coli, which was slightly less than the standard antibiotic i.e., penicillin (MIC = 2.4 ± 1.00 mg mL-1). The compound 11c demonstrated a better binding score (-7.08 kcal mol-1) than ascorbic acid (-5.59 kcal mol-1) and kojic acid (-5.78 kcal mol-1). Molecular docking studies also validate the in vitro anti-tyrosinase assay results; therefore, the molecule 11c can be the lead bacterial tyrosinase inhibitor as well as the antibacterial agent against both types of bacterial strains after suitable structural modifications.

Synthesis, in-vitro antioxidant and anti-inflammatory properties of novel amide derivatives of substituted 2-aminothiophenes and 3,4-dimethoxy cinnamic acid

Novel amide derivatives using substituted 2-aminothiophenes (1A–12A) were synthesized by following a suitable procedure. The synthesized compounds were characterized by physical and spectral data. The compounds were screened for in-vitro antioxidant and anti-inflammatory activities with reference to the standard drugs, Ascorbic acid and Ibuprofen respectively. The majority of the compounds showed good antioxidant activity in DPPH and hydroxyl radical scavenging assays. The synthesized compounds were also tested for in-vitro anti-inflammatory activity by protein denaturation and HRBC membrane stabilization methods. Among all, the compounds 2A and 3A showed significant in-vitro anti-inflammatory activity when compared with the standard drug Ibuprofen.

Novel chalcone-based crown ethers: synthesis, characterization, antioxidant activity, biological evaluations, and wastewater remediation.

Macrocycles play a pivotal and indispensable role within the realms of both medicine and industry. In the course of our research endeavors, we have successfully synthesized five distinct macrocyclic chalcone entities, each showcasing remarkable biological and anti-oxidative properties. Furthermore, these compounds exhibit exceptional promise as potent agents for the removal of dyes in wastewater treatment processes. The synthesis of these key constituents was achieved through the judicious application of the Robinson ether synthesis and Claisen-Schmidt condensation reactions. The structures of compounds 1a-f and 2a-e were characterized by using analytical techniques such as FTIR, 1H NMR, 13C NMR, and DEPT 13C NMR spectroscopy. These macrocycles also underwent in vitro assessments to measure their antibacterial activity using the agar well diffusion method. The results revealed that the macrocyclics were more sensitive to Gram-positive than Gram-negative bacteria. For example, compound 2d exhibited an inhibition zone of 20 mm at 150 ppm. The antioxidant activity as determined via the DPPH method established that all tested compounds showed moderate radical-scavenging ability. Specifically, compound 2e (at 1000 ppm) exhibited antioxidant activity of 79% inhibition of radicals, in comparison to 90% for the standard ascorbic acid. The latter was demonstrated by using methylene blue as an adsorbate under simulated wastewater conditions. Outstandingly, the most effective compounds were 2d and 2c, which achieved removal rates of 96.54% and 92.37%, respectively, for methylene blue dye.

Antioxidant activity of silver nanoparticles synthesized from crud methanolic extract of rumex nervosus

In the present investigation, an attempt was made to prepare nanoparticles by using a medicinal plant Rumex nervosus, because the biological synthesized nanoparticles have been widely used in the field of medicine now. Silver sulfate (Ag2SO4) was used for the synthesis of the silver nanoparticles using the root extract of Rumex nervosus. The synthesized silver nanoparticles from silver sulfate solution through the root extract were characterized using UV-vis spectrophotometry, SEM, and FT-IR methods. The SEM analysis showed the average size of 75 nm with spherical shape and it confirmed the formation of nanoparticles in the sample. Antioxidant activity of the crude extract was evaluated by employing the DPPH radical scavenging assay. The result showed moderate antioxidant activity at various concentration as compared to standard ascorbic acid solution. The synthesized nanoparticles can be used for various applications due to its eco-friendless, nontoxic and compatibility for pharmaceutical and other applications.

Antibacterial and Antioxidant Activity of Biosynthesized Silver Nanoparticle using Cassia Occidentalis

Nanotechnology is a fascinating field of research that has applications in various areas such as material science, medical science, life science, physical and chemical sciences. A study was conducted to determine the antioxidant and antimicrobial properties of silver nanoparticles. The silver nanoparticles were biosynthesized from the leaves of Cassia occidentalis. The antimicrobial effectiveness of the biosynthesized silver nanoparticles was tested against Staphylococcus aureus and Pseudomonas Stutzeri, and in vitro antioxidant activities were measured using DPPH, FRAP, and Hydrogen peroxide. The microorganisms were treated with 10 and 20 µg/mL of the silver nanoparticles and 20 µg/mL of ciprofloxacin for 72 hours. After incubation, the silver nanoparticles significantly inhibited the growth of Staphylococcus aureus (17.00 ± 2.50), which was higher than the inhibition observed with ciprofloxacin (15.00 ± 0.05). The zone of inhibition of Pseudomonas Stutzeri was 15.00 ± 3.00, which was inhibited by the silver nanoparticles compared to ciprofloxacin (22.00 ± 2.00). The silver nanoparticles also showed significant antioxidant activity compared to the standard ascorbic acid. In conclusion, the study found that the biosynthesized silver nanoparticles exhibited antimicrobial and antioxidant properties against the tested microorganisms.

Extraction and Characterization of the Essential Oil from the Leaves of Ocimum basilicum and Evaluation of its Antioxidant Properties

The essential oil was extracted from the leaves of Ocimum basilicum using a modified steam distillation method. The chemical composition and free radical inhibition property of the plant essential oil were investigated. Results from gas chromatography-mass spectrometry revealed the presence of 39 different compounds in the essential oil of Ocimum basilicum. The major components, Terpinen-4-ol (21.31%), Eucalyptol (18.97%), α-Terpineol (14.41%), γ-Terpinene (12.61%), Caryophyllene (11.90%), α-Pinene (6.11%), and β-Myrcene (5.54%), were found in high percentages. The antioxidant activity of the essential oil was evaluated using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and hydrogen peroxide free radical scavenging assays, with Ascorbic acid as a standard drug. The results showed that the essential oil extracted from Ocimum basilicum leaves exhibited positive effects at different concentrations when tested using both methods. At a concentration of 2.5 μL/mL, the Ocimum basilicum essential oil significantly scavenged 60.89% of hydrogen peroxide radicals, while the standard Ascorbic acid scavenged 79.13%. Similarly, at a concentration of 10 μL/mL, the plant’s volatile oil inhibits 87.12% of DPPH radicals, while the standard Ascorbic acid inhibits 90.40%. This study highlights the potential of the essential oil derived from Ocimum basilicum leaves as a valuable source of compounds with free radical scavenging properties, consistent with its traditional medicinal applications. Graphical Abstract showing the entire experimental process:

Evaluation of the effect of Musa paradisiaca L. rhizome on Saccharomyces glucose absorption and DPPH free radical scavenging capacity

Introduction: Musa paradisiaca is a common edible plant used in traditional medical systems for its medicinal properties. In this study, in vitro anti-hyperglycaemic potential and in vitro antioxidant activity of M. paradisiaca rhizome were investigated. Methods: Dried rhizome of M. paradisiaca was sequentially extracted to hexane and dichloromethane using cold maceration technique. Stock concentrations of hexane extract (35.35 mg/mL) and dichloromethane extract (22.14 mg/mL) were diluted to prepare different concentrations and were used to evaluate the effects of plant extracts on glucose uptake potential by yeast cells and DPPH free radical scavenging capacity compared to metformin and ascorbic acid standards respectively. Results: The extracts improved the glucose uptake through yeast plasma membrane, since a linear relationship in glucose uptake by yeast cells wasobserved with gradual increase in concentration of the plant extract. In terms of glucose adsorption capacity, dichloromethane extract of plant possessed a significant (p<0.05) activity compared to the hexane extract at higher glucose concentrations, but this activity was significantly less compared to metformin standard (p<0.05). Further, dichloromethane extract demonstrated a higher level of glucose adsorption potential than hexane extract. Same extract had the highest DPPH radical scavenging potential in antioxidant assay. However, this activity was concentration-dependent, and both extracts showed lower radical scavenging potentials compared to the ascorbic acid standard. Conclusion: Dichloromethane extract of M. paradisiaca rhizome is more biologically active compared to its hexane extract in terms of in vitro glucose adsorption potential and antioxidant properties. However, both extracts showed significantly lower activity compared to metformin in glucose uptake assay while ascorbic acid showed the highest activity in free radical scavenging.
 Keywords: DPPH, Glucose adsorption, Musa paradisiaca rhizome, Saccharomyces

Preclinical Evaluation of Nerolidol’s Hepatoprotective and Nephroprotective Potential

Background: Due to the potential negative effects of artificial food additives on health and the recent surge in consumer awareness of the issue, natural goods are becoming more and more popular in diets. Objective: The main objective of the current study is the evaluation of the protective effect and antioxidant role of Nerolidol against alloxan-induced oxidative stress, hepatotoxicity, and nephrotoxicity. Method: The present experiment was designed as Group I (control), Group II (Alloxan monohydrate, 120 mg/kg i.p), Group III (Ascorbic acid 250 mg/kg p.o), Group IV (Nerolidol 100 mg/kg p.o), Group V (Nerolidol 200 mg/kg p.o), Group VI (Nerolidol 300 mg/kg p.o). Alloxan was given to all groups excluding control group in order to induce hepatorenal toxicity. The groups III, IV, V and VI received the Standard Ascorbic acid and Nerolidol after 72 hrs. of alloxan administration for consecutive 14 days. The protective roles and antioxidant activity of Nerolidol against Alloxan induced oxidative stress and hepatorenal toxicity were evaluated by histopathological changes, measuring hepatic and renal damage biomarkers, antioxidant enzyme levels and malondialdehyde (MDA) parameters in the liver and kidney tissues of rats. Result and Conclusion: The biochemical analysis showed a decrease in serum AST, ALT, ALP, and LDH enzymes, total protein, creatinine, bilirubin, and urea in group III and test groups compared to that of group II. Nerolidol also restored the Alloxan-induced MDA and antioxidant enzyme level to control. Hepatorenal protection of Nerolidol was confirmed by almost normal histological findings in test groups.

‘Cephalandole A’ analogues as a new class of antioxidant agents: Design, microwave-assisted synthesis, bioevaluation, SAR and in silico studies

Herein, a novel series of natural product alkaloid ‘Cephalandole A’ analogues 19a-y, and 20a-d were rapidly synthesised under microwave irradiation conditions using PTSA in catalytic amount dissolved in acetonitrile at 90 °C for 15 min. The developed one-pot protocol is operationally simple, rapid (15 min) and furnished the target analogues in up to 90 % yield. All the synthesised analogues of Cephalandole A were evaluated for their in vitro antioxidant activity using DPPH free-radical scavenging and FRAP assays. The in vitro studies of DPPH radical scavenging assay provided 19a (IC50 = 11.87 ± 0.14 µg/mL), 19f (IC50 = 16.34 ± 0.27 µg/mL), 19n (IC50 = 15.37 ± 0.11 µg/mL) and 20a (IC50 = 14.54 ± 0.31 µg/mL) respectively, as the most active compounds of the series. In addition, the analogous 19d (556.3 ± 13.1 µM) and 19v (551.9 ± 14.2 µM) showed promising activity in FRAP assay. However, the standard reference drug ascorbic acid showed an IC50 value of 4.57 µg/mL in the DPPH assay, and BHT showed C0.5FRAP = 546.0 ± 13.6 μM in the FRAP assay. In silico studies were performed to validate the wet results. To the best of our knowledge, this is the first report demonstrating ‘Cephalandole A’ analogues as a new class of antioxidant agents.

Phytochemical Analysis and Biological Activities of Ficus racemosa Linn., Myrica esculenta Buch-Ham. Ex D. Don and Urtica dioica Linn.

Medicinal plants like Ficus racemosa, Myrica esculenta, and Urtica dioica were traditionally used to treat diabetes, cough, fever etc. These plants were collected from Kathmandu and Gorkha district of Nepal and subjected to various biological activities. Methanol extract of all three selected plants when subjected to phytochemical analysis showed the presence of various chemical constituents such polyphenols, flavonoids, tannins, saponins, and glycosides. The methanol extract of F. racemosa bark was found with strongest DPPH radical neutralization activity having IC50 value of 41.48 µg/mL, which was comparable with standard ascorbic acid (31.07 µg/mL). The bark of F. racemosa contained the highest level of total phenolic and total flavonoid contents with the values of 168.89 ± 1.08 mg GAE/g and 41.56 ± 1.83 mg QE/g respectively. The methanol extract of bark of F. racemosa showed high α-amylase inhibitory activity with IC50 value of 164.99 μg/mL. Brine shrimp bioassay showed that the methanol extracts of bark of F. racemosa, bark of M. esculenta, leaves of M. esculenta and U. dioica were lethal to brine shrimp nauplii with LC50 values of 70.79, 177.83, 190.54 and 269.15 µg/mL respectively. Methanol extract of leaves of U. dioica was least active in these biological activities.

Comparative evaluation of phytochemical, in vitro antioxidant activities and elemental composition of the fruit, leaves, and stem bark of Tetrapleura tetraptera

Introduction: Nowadays, medicinal plants are widely accepted as a better option than synthetic medications due to their lower cost and little to no side effects. The current study aimed to compare the elemental composition, phytochemical profile, and antioxidant efficacy of n-hexane extracts derived from Tetrapleura tetraptera fruit, stem bark, and leaves. Methods: The fresh fruits, leaves, and stem bark of the plant were collected and dried. The dried samples were pulverized and exhaustively extracted with n-hexane. The extracts were screened for both qualitative and quantitative phytochemical constituents. Antioxidant parameters such as Ferric Reducing Antioxidant Property (FRAP) and 2,2-Diphenyl-1-picryl hydroxyl radical scavenging activity (DPPH) were also carried out. The elemental analysis of the various organs was also evaluated using standard protocols. Results: The presence of alkaloids, flavonoids, tannins, saponins, terpenes, resins, and phenolswas revealed in the phytochemical data. The stem bark of T. tetraptera has higher concentrations of alkaloids and flavonoids than the leaf and fruit, according to a quantitative examination of the phytochemical elements of the plant. The stem bark had the highest Total Phenolic Content at 1000 µg/mL, whereas the leaves had the lowest TPC at 200 µg/mL.At a concentration of 1000 µg/mL, the stem bark exhibited the greatest activity of total flavonoid (TFC) in the plant extracts, followed by the fruits and leaves. At 1000 µg/mL concentration, the FRAP test revealed the maximum activity in the stem bark. Generally speaking, when concentration rises, so do the TPC, TFC, and FRAP activities. Compared to the standard ascorbic acid (2.76 µg/mL), stem bark exhibited the highest level of DPPH antioxidant activity, with an IC 50 of 13.34 µg/mL. The elemental analysis revealed that the stem bark had the highest concentrations of Ca, Mg, and Fe, followed by the fruit and leaves, in that order.Conclusion: This research result has established that the plant, T tetraptera can be standardized and offer an alternative eco-friendly drug for immunity building. The stem barks are underutilized, however, its phytochemical studies and other investigations pointed to its potential in the cosmeceutical industries and medicine. Keywords: Antioxidant activity, ethnomedicine, ferric-reducing assay, medicinal plant

Design, Development and Evaluation of Nanosponges Loaded Topical Gel for Rejuvenation of Skin

The study aimed the development of nanosponges was the choice due to the numerous advantages of this novel technology over the others. Rutin was chosen as it has excellent antioxidant potential. The compatibility study was performed using Fourier transform infrared (FTIR) and there was no interaction found. The optimization study was brought off by Design expert software (version.13). Nanosponges were prepared by emulsion solvent diffusion method. The prepared sponges were brimmed in a night gel formulation for their suitable delivery to the skin. The prepared nanosponges were evaluated for various parameters such as particle size analysis, entrapment efficiency and zeta potential which were found in the acceptable limit. In-vitro permeation study was carried out using Franz-diffusion cell and the cumulative percent drug permeation was found to be 69 to 84.5% in 30 hours. A gel formulation was prepared using rutin-loaded nanosponges and studied for various parameters such as pH, viscosity, and extrudability for various combinations using NS-4. Ex-vivo drug diffusion study reveals that the night gel took 300 minutes for 78.26 to 94.16% permeation. The IC50 values of the flavonoid combination, NS-4 was found to be 54.70, 52.76, and 51.65 μg/mL in the different in-vitro models viz. DPPH, when compared to that of the standard ascorbic acid. Conclusively, the objective of delivery of rutin using nanosponges as carriers for the target delivery was achieved by NS-4 formulation and successfully delivered as night gel for skin rejuvenation.

Tandem aqueous extract of onion catalyzed Knoevenagel condensation-Michael addition-cyclization: A green synthesis of 2-amino- 3-cyano-4H-pyran derivatives and their anti-oxidant and molecular docking studies

Aqueous extract of onion catalyzed tandem process incorporating Knoevenagel condensation followed by Michael addition-cyclization is revealed using aldehyde 1, malononitrile 2a and an active methylene compound 3. This method caused diverse 2-amino- 3-cyano-4H-pyran annulated heterocyclic scaffolds in excellent yields (up to 98 %). The synthesized compounds 4ah were also analyzed by single-crystal X-ray diffraction. The reactivity of the active methylene compounds and reasonable mechanism for sequential tandem reactions have been described. Also, this methodology has a simple, easy workup, short reaction time, without column chromatography and eco-friendly reaction conditions. Seventeen out of forty-five synthesized pyran derivatives were screened for their in vitro antioxidant studies. Among the compounds 4ai, 4aj, 4al, 4cd, 4ca, 4cb, 4cc, 4cd have shown excellent and 4aa, 4ac, 4ae, 4ah have exhibited comparable antioxidant activity with ascorbic acid standard. Compounds 4ch-4ck exhibited excellent antioxidant activity than standard. Moreover, mushroom tyrosinase (mh-Tyr) has performed molecular docking properties.

Isolation and characterization of undescribed flavonoid from Abrus precatorius L. based on HPTLC-DPPH bioautography and its cytotoxicity evaluation

BackgroundNaturally derived compounds play a tremendous role as a drug as well as lead structure for the development of APIs. Therefore, isolation and characterization of compounds from nature are needed to alleviate life-threatening diseases. A. precatorius L. belongs to the family Leguminosae and is valued for its medicinal properties. Therefore, in this study, efforts are being made to isolate bioactive entity based on HPTLC-DPPH bioautography from APHA extract. Among all the separated compounds on TLC plate, the one (APSP-3) at Rf = 0.67 showed significant antioxidant activity, and hence, APSP-3 was further subjected to isolation, purification, and structural characterization using diverse analytical modus operandi such as 1D and 2D NMR, FTIR, HPLC–MS/MS, and elemental analysis. In addition, antioxidant and cytotoxicity evaluation of APHA extract and APSP-3 was pursued by standard DPPH and colorimetric MTT assays, respectively.ResultsAntioxidative isolated compound APSP-3 was scrutinized based on HPTLC-DPPH bioautography. The APSP-3 was found novel and spectroscopic data revealed the plausible structure; 7-hydroxy-3,5-dimethoxy-2-(4-((3,4,5-trihydroxy-6-(hydroxymethyl) tetrahydro-2H-pyran-2-yl)oxy) phenyl)-4H-chromen-4-one. Moreover, APSP-3 ascribed higher free radical scavenging activity with IC50 = 38.70 ± 3.5 µg/mL than standard ascorbic acid (75.19 ± 1.5 µg/mL). Cytotoxicity evaluation of APHA extract exhibited IC50 value 122.09 µg/mL for HepG2, 122.61 µg/mL for MCF-7, and 48.08 µg/mL for HCT116 cell lines, while APSP-3 displayed IC50 values 96.75 for HepG2, 61.67 for MCF-7, and 47.61 µg/mL for HCT116 cell lines.ConclusionsIn a nutshell, HPTLC-directed bioautography leads to the capturing of new flavonoid entity having antioxidant potency from APHA extract. The IC50 values obtained from cytotoxicity establish a dose–response relationship helping to determine the concentration at which a substance begins to exhibit toxic effects. This fundamental information is crucial for establishing safe dosage level in medical and pharmaceutical applications. Further, research engrossed in assessing other bioactivities involving in silico and in vivo studies obliged to offer a promising and secure portrayal for clinical implications.Graphical abstract

Evaluation of Antioxidant Capacity of Methanol Extracts of Leaf and Stem Bark of Tinospora Cordifolia

Conventionally used herbs are the major sources of biologically active phytoconstituents that are extensively used for the management of several health complications particularly in developing countries. Tinospora cordifolia, locally known as Gurjo, is one of the most widely utilized medicinal plants in Nepal. This study was carried out on quantifying the total phenolic and flavonoid contents, and evaluating antioxidant potential of the methanolic extracts of stem barks and leaf of a wild plant collected from Rupa Village of Kaski District of Nepal. The Folin-Ciocalteu reagent (FCR) method showed a total phenolic content of 50.84 ± 0.38 and 41.39 ± 0.44 mg GAE/g in the extracts of stem barks and leaves respectively. The AlCl3-based colorimetric method showed the total flavonoid contents of 27.44 ± 0.68 mg QE/g in stem barks and 18.44 ± 0.25 mg QE/g in the leaves extract. Besides, the antioxidant activity was evaluated by 2, 2-diphenyl-1-picrylhydrazyl (DPPH) method. The stem bark exhibited higher antioxidant activity (IC50 = 36.50 ± 0.79 µg/mL) than that of the leaf extract (IC50 = 50.77 ± 1.29 µg/mL), as compared to the standard ascorbic acid (IC50 = 10.82 ± 0.04 µg/mL). These findings validate the traditional practice of using the plant, underscore the existence of a diverse range of bioactive compounds, and highlight the necessity for further investigations into its potential health benefits.

GC-FID spectroscopic analysis and antioxidant activities of methanolic fraction of Cassia tora leaves

IntroductionFrom time immemorial, different parts of Cassia tora (Jue ming zi) have found application in Chinese medicine. There is a reputation for the therapeutic properties of the plant's leaves, seeds, and roots. The objective of this study is to ascertain the antioxidant properties and bioactive compounds found in Cassia tora leaf. Materials and methodPhytochemical and antioxidant studies were carried out using standard analytical techniques. Bioactive compounds were analysed using GC FID. ResultsResults of the quantitative phytochemical analysis of the methanolic fraction of Cassia tora leaves indicated the presence of saponins (71,760±943.2µg/ml), terpenoids (47,466.70±46.2µg/ml), tannins (21,253.30±46.2µg/ml), flavonoids (14,682.70±40.3µg/ml), phenols (30,986.70±46.2µg/ml), steroids (13,557.30±24.4µg/ml), alkaloids (9770.67±9.2µg/ml), glycosides (5434.67±139.8µg/ml). Using ferric reducing antioxidant power (FRAP), 2,2-diphenyl-1-picrylhydrazyl (DPPH), and total antioxidant capacity (TAC) to analyze the antioxidant properties of the methanolic fraction of Cassia tora leaves, it was discovered that the higher the scavenging power of the fraction, the lower the concentration of the standard (ascorbic acid). In comparison to the standard (ascorbic acid), the fraction had the maximum antioxidant capacity at 6.86mg/ml. Total antioxidant power in the fraction ranged from 1.78mg/ml to 16mg/ml. Twenty (20) bioactive chemicals were found in the methanol fraction of Cassia tora leaves, according to the results of the gas chromatography flame ionization detector (GC-FID) investigation. ConclusionThe findings of this current study demonstrate that the leaves of Cassia tora are rich in numerous bioactive compounds and are natural sources of antioxidants.

FREE RADICAL SCAVENGING ACTIVITY OF PLEUROTUS OSTREATUS AGAINST CCL4-INDUCED HEPATIC DAMAGE IN WISTER RATS

Objective: The present study was aimed to evaluate the anti-oxidant effect of Pleurotus ostreatus using in vitro and in vivo methodology. Methods: Methanolic extract of Pleurotus ostreatus (MEPO) was prepared by cold maceration technique. Rats weighing 150-200 g were divided into 6 groups of six each (n=6). Group I served as control (0.9% Nacl), group II was considered as the positive control, administered with CCl4 dissolved in olive oil (intraperitoneal injection at 0.5 mg/kg body weight), group III was given with CCl4+standard drug sylimarin (100 mg/kg body weight, p. o.), group IV, V and VI were administered with CCl4+MEPO at 200, 400 and 800 mg/kg orally for a period of 21 d. The liver injury was induced by the administration of CCl4 intraperitoneally with a single dose of CCl4 (0.5 mg/kg body weight) as a 1:1 (v/v) solution in olive oil. Results: In the Hydroxyl free radical scavenging assay, the IC50 values of the test extract was found to be 72.1±1.68 as compared with the standard drug (IC50-66.3±1.02), which was considered as significant (***p<0.001). In the reducing power assay, all the absorbance values were comparable to standard ascorbic acid and showed maximum reducing ability at the concentration of 500 µg/ml. In the in vivo anti-oxidant study, administration of MEPO to injury-induced rats at the dose of 400 and 800 mg/kg, significantly increased (**p<0.001) the levels of SOD and CAT, with a significant reduction in the MDA levels. Conclusion: The current study explored a potential source for anti-oxidants in the methanolic extract of Pleurotus ostreatus, thus seems to be protective to liver in CCl4-induced hepatic injury.