Naresh Chandra

Free radicals, antioxidants and functional foods: Impact on human health

In recent years, there has been a great deal of attention toward the field of free radical chemistry. Free radicals reactive oxygen species and reactive nitrogen species are generated by our body by various endogenous systems, exposure to different physiochemical conditions or pathological states. A balance between free radicals and antioxidants is necessary for proper physiological function. If free radicals overwhelm the bodys ability to regulate them, a condition known as oxidative stress ensues. Free radicals thus adversely alter lipids, proteins, and DNA and trigger a number of human diseases. Hence application of external source of antioxidants can assist in coping this oxidative stress. Synthetic antioxidants such as butylated hydroxytoluene and butylated hydroxyanisole have recently been reported to be dangerous for human health. Thus, the search for effective, nontoxic natural compounds with antioxidative activity has been intensified in recent years. The present review provides a brief overview on oxidative stress mediated cellular damages and role of dietary antioxidants as functional foods in the management of human diseases.

Gastroprotective effect of aqueous extract and mucilage from Bryophyllum pinnatum (Lam.) Kurz.

Context: Bryophyllum pinnatum is used as traditional medicine in India, Africa, Tropical America and China for treatment of various diseases. B. pinnatum contains different groups of phytoconstituents viz., flavonoid, terpenoids, alkaloid, phenolic compounds. Aim: The present study was carried out to evaluate the gastroprotective activity of B. pinnatum whole plant aqueous extract, and mucilage (MUC) isolated from the whole plant against ethanol induced gastric ulcer. Materials and Methods: Pretreatment of rats with aqueous extract at dose level of 500 and 750 mg/kg b.w., MUC at 500 mg/kg dose level and standard drug Rabeprazole at dose level of 20 mg/kg b.w. where given for 7 days. Results: The aqueous whole plant extract of B. pinnatum at dose of 750 mg/kg p.o. and MUC at dose of 500 mg/kg p.o. markedly decrease the incidence of ulcers in ethanol induced ulcer rats. In ethanol induced ulcer rats, there was a decrease in the gastric volume, free and total acidity and ulcerative index as compared to the control group. Total carbohydrate content was found to be an increase as compare to control the group. The aqueous whole plant extract of B. pinnatum at dose of 750 mg/kg showed a significant reduction in the above parameters which was comparable to the standard drug rabeprazole (20 mg/kg). B. pinnatum extract and MUC showed protection index 72.69 and 69.65% respectively, whereas standard drug rabeprazole showed protection index 75.49%. Conclusions: Whole plant extracts of B. pinnatum and MUC has potent gastroprotective effect which can be further clinically studied for new drug development.

Acute toxicity studies of Some Indian Medicinal plants

Abstract It is presumed that ayurvedic drugs have lesser side effects as compared to allopathic drugs. For the safety to use these plants and preparations (gel and powder forms), the medicinal plants need to be evaluated for their toxicity. The aim of this study was to test the acute toxicity of three medicinal plants, Terminalia bellerica (Gertn.) Roxb. fruits, Moringa pterigosperma (Gaertn) leaves, Cassia tora Linn. leaves. The acute toxicity study was studied on Swiss mice with a dose of 3 and 5 g/Kg body weight orally. The single administration exposure of the whole plant powder in the form of aqueous slurry on Swiss mice was carried out and the exposure route was oral with water as a vehicle. The observations of changes in body weight, food and water intake as well as cage side observations were reported. The plants were found to be nontoxic

Antioxidant Availabiltiy of Beheda (Terminalia bellerica (Roxb.)) in Relation to its Medicinal Uses

Abstract Oxidative stress arises from an imbalance in the generation and metabolisms of ROS, with more of ROS being produced, than that is metabolized. Oxidative stress plays a significant pathological role in human diseases. However, the antioxidant supplements may be used to help the human body to reduce oxidative damage. Therefore the present study evaluated the antioxidant activity of Terminalia bellerica (Gertn.) Roxb. fruits. The study was designed to evaluate and compare the antioxidant activity, total phenolics, flavonoids content of aqueous (AETB) and ethanolic (EETB) extracts of fruits. The antioxidant activity was assessed by DPPH (1,1-diphenyl-1,2-picryl hydrazyl), ABTS (2,2-Azino-bis 3-ethyl benothiazoline-6-sulfonic acid diammonium salt), nitric oxide, superoxide and hydroxyl radical scavenging assay, FRAP (Ferric Reducing Antioxidant Power), reducing power and TAC (Total antioxidant capacity). AETB has shown higher antioxidant activity (% inhibition) as compared to EETB in nitric oxide, superoxide, ABTS(2,2-Azino-bis 3-ethyl benothiazoline-6-sulfonic acid diammonium salt) radical scavenging assay with IC50 values 41.42±1.23, 892.85±2.73, 23.74±2.0 in AETB and 93.16±1.93, 3496.50±5.21, 55.89±2.21 in EETB respectively. Like antioxidant activity the reducing power increases in a dose dependent manner showing higher absorbance at 700 nm for AETB i.e. 0.95±0.03 as compared to EETB i.e. 0.43±0.01 at 500μg/ml. The FRAP values were found for AETB 1.68±0.07, EETB 1.06±0.03 and TAC values were found for AETB 2.53±0.07 and EETB 2.90±0.01. The amounts of total phenolic (TPC) and flavonoid content (TFC) were also determined. The results suggest that TPC and TFC contribute significantly to the antioxidant activity of the Terminalia bellerica (Gertn.) Roxb. Fruits.