Background. Nelumbo nucifera Gaertn. and Nymphaea lotus L. var. pubescens (Willd.) are both aquatic rhizomatous perennial plants mostly found in the tropical region of Nepal, India, Bangladesh, China, and Eastern Asia. Nymphaea pubescens and Nelumbo nucifera plants are famous for their different biological activities such as antidiabetic, antioxidant, hepatoprotective, antidiarrheal, and anti-inflammatory properties. Objective. The present study majorly focused on the determination of in vitro antioxidant and antidiabetic properties of Nelumbo nucifera and Nymphaea pubescens. Methods. In vitro α-glucosidase inhibition was performed using PNPG as a substrate. Antioxidant property of the plant extract was determined by DPPH free radical scavenging assay. The aluminium trichloride method was done for the estimation of total flavonoid content. Likewise, Folin–Ciocalteu reagent was used for determining total phenolic content. Results. The total phenolic content of N. nucifera and N. pubescens was found to be 172.827 ± 0.41 and 194.87 ± 0.93 mg GAE/g, respectively, while the total flavonoid content was reported 17.12 ± 1.04 and 34.59 ± 1.73 mg QE/g, respectively. The IC50 values of the crude extract and its fractions of N. nucifera against the DPPH free radical ranged from 33.46 ± 0.6 to 3.52 ± 0.09 μg/mL, while that of the N. pubescens ranged from 14.30 ± 0.43 to 1.43 ± 0.08 μg/mL. Similarly, for the in vitro α-glucosidase inhibition activity, the IC50 of the crude extract and its fractions of N. nucifera varied from 349.86 ± 2.91 to 29.06 ± 0.24 μg/mL and that of N. pubescens ranged from 224.4 ± 6.85 to 5.29 ± 0.39 μg/mL. Conclusion. Both aquatic plants N. nucifera and N. pubescens show antioxidant properties and can inhibit α-glucosidase in in vitro. Further research is required to identify the inhibiting compounds.

Background: Diabetes has become a considerably more frequent condition and has increased alarmingly in recent years, possibly due to the adoption of modern lifestyle and food habits. The two prominent features of diabetes mellitus are high blood glucose and insulin deficiency, leading to severe consequences. Developing next-generation anti-diabetic medicines with fewer side effects has been a major focus in this situation. Objective: This research aimed to investigate the total phenolic and flavonoid content, antioxidant, antibacterial, α-amylase, and α-glucosidase inhibition activity, as well as in silico analysis of Mimosa pudica L. Methods: The inhibitory activity against α-amylase and α-glucosidase was performed using CNPG3 and PNPG, respectively. Antioxidant activity was estimated using DPPH free radical scavenging assay. The well diffusion method was used for the antibacterial. Using folin- ciocalteu’s reagent, the total phenolic content was determined. The total flavonoid content was determined using the aluminium trichloride method. In addition, molecular docking was performed using autodock vina. Results: Inhibition of α-glucosidase (IC50 = 1.059±0.14μg/mL) was found to be more significant than α-amylase (IC50 = 164.9±0.95μg/mL). The plant was also found to have antioxidant activity (IC50 = 8.207±0.23µg/mL), as well as antibacterial activity against Staphylococcus aureus (ZOI = 13mm) and Bacillus subtilis (ZOI = 10mm). Similarly, the total phenolic and flavonoid content was found to be 177.93±1.8 mg GAE/g, and 19.747±6.11 mg QE/g, respectively. In addition, compounds (stigmasterol, quercetin, and avicularin) isolated from M. pudica showed perfect binding to the enzyme’s active site. Conclusion: Mimosa pudica of Nepalese origin possess potent inhibition against digestive enzymes. Therefore, M. pudica can be used as an alternative therapeutic source to combat the global threat of diabetes.

Background: Rhus chinensis Mill, indigenous wild fruit primarily found in the hilly region of Nepal. The ripe fruit is very sour and considered medicinal as a remedy for colic pain. In addition, their astringent and styptic qualities are used internally to treat illnesses such as diarrhea and hemorrhage. Also, they are used as a common component of polyherbal medications for diabetic mellitus. Objectives: This work aimed to determine the total phenolic and flavonoid content, antioxidant, antibacterial, α-glucosidase, and α-amylase inhibition activity of the crude extract and fractions of Rhus chinensis Mill. Additionally, molecular docking of compounds from Rhus chinensis was performed. Methods: Folin Ciocalteu’s (FC) reagent was used for the estimation of total phenolic content. Likewise, the aluminium trichloride method was applied for the determination of total flavonoid content. For the antioxidant activity, a 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay was performed. Furthermore, the substrate-based enzyme inhibition assay was carried out for α-glucosidase and α-amylase inhibition activity of R. chinensis. P-nitrophenyl-α-D-glucopyranoside (PNPG) and 2-Chloro-4-Nitrophenyl-α-D-Maltotrioside (CNPG3) were used as substrates for α-glucosidase and α-amylase inhibition assay, respectively. Similarly, the well-diffusion method was used for the antibacterial activity. Autodock vina was used to perform the molecular docking. Results: The total phenolic and flavonoid content of R. chinensis fruit were found 117.092±1.1 mg GAE/g and 62.41±1.23 mg QE/g, respectively. The IC50 value for antioxidant activity of the crude extract and its fractions ranged from 3.12±1.15μg/mL to 50.85±2.10μg/mL. Similarly, the IC50 for α-glucosidase inhibition ranged from2.33±1.01µg/mL to 28.34±2.79μg/mL. Likewise, The IC50 of R. chinensis crude methanolic extract against α-amylase was 120.3±1.382µg/mL. The antibacterial activity of R. chinensis was effective against gram-positive bacteria; Staphylococcus aureus (ZOI=11.0) and Bacillus subtilis (ZOI=9.0). Quercetin-3-O-rhamnoside and Myricetin 3-O-rhamnoside showed excellent binding to the active site of protein with binding energy -9.4kcal/mol and -9.6kcal/mol, respectively. Conclusion: Rhus chinensis Mill is a potent antioxidant and inhibits enzymes; α-glucosidase and α-amylase. In addition, the methanolic extract of this plant shows antibacterial activity. However, further research is required to determine the inhibiting compounds.

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Background: Diabetes has become a major health problem due to its high prevalence, morbidity, and mortality rate. Reducing postprandial hyperglycemia has become the main target in the treatment of diabetes mellitus. So, developing new drugs with fewer side effects has been a major priority. Objective: The main objective of this study is to investigate total phenolic and flavonoid content, antioxidant activity, α-glucosidase, and α-amylase inhibition activity of Persea Americana Mill (avocado) pulp and seed. Methods: The α-glucosidase and α-amylase inhibition activity were performed using substrates PNPG and CNPG3, respectively. DPPH free radical scavenging assay was used to perform the antioxidant activity. The total phenolic content was estimated using folin-ciocalu’s reagent. Likewise, aluminium trichloride method was applied to find out the total flavonoid content. Results: The crude methanolic extract of avocado seed revealed potent α-glucosidase inhibition activity with an IC50 1.959±0.93µg/mL followed by the avocado pulp 308±2.36µg/mL. Similarly, the IC50 for the α-amylase inhibition activity of avocado seed was found to be 120.3±1.382µg/mL. In addition, the avocado pulp and seed revealed a significant antioxidant activity with IC50 value 75.01±0.72µg/mL, and 6.445±0.62µg/mL, respectively compared to the standard quercetin 1.525±0.5µg/mL. The total phenolic content of avocado pulp and the seed was reported 7.031±2.87 mg of GAE/g, and 142.96±1.589 mg of GAE/g, respectively. Similarly, the total flavonoid content of avocado pulp and the seed was found to be 6.313±1.301 mg of QE/g and 48.696±0.110 mg/GAE/g, respectively. Conclusions: The avocado seed of Nepali origin was found to inhibit the digestive enzyme significantly. These findings indicate that avocado fruit of Nepali origin has the potential to develop as an alternative food therapy for diabetic patients. Further research is required to find out the inhibitor compounds.

Background: Essential oils (EOs) are a mixture of volatile compounds of plant origin, which possess substantial biological activities such as antioxidant, antimicrobial, and antifungal activity. Objective: This study aimed to determine the chemical composition, antioxidant, and antibacterial activity of essential oil isolated from Cymbopogon winterianusJowitt. Methods:: The hydro-distillation method was used for the isolation of essential oil. The chemical composition of the isolated essential oil was analyzed using the gas chromatography/mass spectrometry (GC-MS) technique. Antioxidant activity was determined using2,2-Diphenyl-1-picrylhydrazyl(DPPH) free radical scavenging assay, and the IC50 value was calculated. The well-diffusion method was applied for the antibacterial activity, and the zone of inhibition (ZOI) was measured. Results: The essential oil from Cymbopogon winterianusJowitt was isolated with a 0.5% yield. Gas Chromatography-Mass Spectrometry(GC-MS) analysis reported 19 different compounds, out of which, Geraniol (28.87%), Citronellal (11.85%), Citronellol (10.88%), Geranial (9.19%), trans-Geranyl acetate (9.11%), and Neral (8.02%) were found to be the major constituents. The essential oil was a promising antioxidant with an IC50 value of 0.458±0.39µg/mL compared to the standard Quercetin 1.187±0.22µg/mL.In addition, the isolated essential oil revealed antibacterial activity against Staphylococcus aureus (ZOI=13.2mm), Bacillus subtilis (ZOI=9.9mm), and Enterococcus faecalis (ZOI=8.4mm). Conclusions: The essential oil isolated from Cymbopogon winterianusJowittexhibits antioxidant and antibacterial activity, implying that it could find use in modern medicine.

Background: Diabetes mellitus is a metabolic disorder that has become a major health issue in the modern era due to long-term health consequences. α-amylase and α-glucosidase are the key enzymes involved in the digestion of starchy foods, and the inhibition of these enzymes is regarded as a postprandial hyperglycemia control strategy. Objective: The primary goal of this work is to examine the antioxidant activity as well as α- glucosidase inhibitory activity of Polygonatum verticillatum rhizomes via in vitro test. Method: The in vitro α-glucosidase inhibition activity was performed using p-nitrophenyl-α- Dglucopyranoside (PNPG) substrate. 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay was performed to estimate the antioxidant activity. Results: The in vitro α-glucosidase inhibitory activity of Polygonatum verticillatum was investigated for the very first time. Of the three fractions and a crude extract, the ethyl acetate (EA) fraction disclosed potent inhibition activity against α-glucosidase enzyme with an IC50 value of 22.3 ± 0.1 μg/mL. Likewise, the IC50 values for dichloromethane (DCM) fraction and the crude extract against α- glucosidase were reported at 34 ± 0.1 μg/mL and 402.2 ± 0.2 μg/mL, respectively. Similarly, the EA fraction, crude extract, and DCM fraction disclosed promising antioxidant activity with IC50 = 55 ± 0.3 μg/mL, 171.5 ± 0.6 μg/mL, and 164.1 ± 3.4 μg/mL, respectively. Conclusion: These findings concluded that among the crude extract and fractions of Polygonatum verticillatum of Nepalese origin, the EA fraction constituted a potent α-glucosidase inhibiting and antioxidant agent. Further research is required to expose the inhibiting compounds.