EVALUATION OF PHYTOCHEMICALS, REDUCING POWER, ANTIOXIDANT ACTIVITY AND IN-VITRO LIPID PEROXIDATION ACTIVITY OF WHEAT GRASS JUICE

HTML Full Text

EVALUATION OF PHYTOCHEMICALS, REDUCING POWER, ANTIOXIDANT ACTIVITY AND IN-VITRO LIPID PEROXIDATION ACTIVITY OF WHEAT GRASS JUICE

N. Jangle and P. Padmanabhan^*

Department of Biochemistry, Rural Medical College, Pravara Institute of Medical Sciences (DU), Loni - 413736, Ahmednagar, Maharashtra, India

ABSTRACT: Oxidative stress is a condition due to excessive production of free radicals than the ability of the antioxidant system to counteract them. Antioxidants scavenge and suppress the deleterious effects of free radicals. Both exogenous and endogenous sources of antioxidants are important in pathological conditions. Exogenous antioxidants include dietary sources and even include medicinal plants. These medicinal plants contain phytochemicals which contribute to the beneficial antioxidant activity. Wheat germinated over a period of 9-10 days is generally called wheat grass. The purpose of this work is to determine the phenolic, flavonoids, flavonols and total alkaloids from wheat grass juice. Free radical scavenging activity of wheat grass juice was evaluated by using DPPH , nitric oxide, hydroxyl radical and total antioxidant power by FRAP assay and antilipidperoxidation activity by using mice liver and brain. Wheat grass juice is found to have good antioxidant action in various models due to its polyphenols and phytochemicals.

Keywords:

Wheat Grass Juice,

Phytochemicals, Free Radicals, Antioxidant, Antilipidperoxidation

INTRODUCTION: Oxidative stress in human beings is a condition when the sensitive homeostasis between free radicals and antioxidants is disturbed. This is due to excessive production of free radicals than the capacity of antioxidants to counteract on them ¹.

The radicals are capable of damaging macromolecules and cause various human diseases such as neurodegenerative disorders, cardiovascular diseases, diabetes mellitus and different forms of cancer.

Antioxidants scavenge and suppress the deleterious effects of free radicals. Under normal conditions the endogenous antioxidants in human body are active defense against free radicals. But, in pathological conditions, the additional antioxidants from diet as well as natural sources such as from medicinal plants are necessary for the recovery to normalcy ².

These medicinal plants contain phytochemicals such as total phenolic compounds, flavonoids, flavonols, tannins, nitrogen compounds such as alkaloids, amines, vitamins, terpenoids which contribute to the beneficial antioxidant activity ³.

The consumption of wheat grass in the Western world started in 1930s, as a result of experiments by Charles F. Schnabel in his attempts to popularize the medicinal plant. The usage of wheat grass juice for therapeutic purpose was developed and popularized by Dr. Ann Wigmore (1909 – 1996) U.S.A, founder- director of Hippocrates Health Institute, Boston, U.S.A. It is reported to be safe and effective for the treatment of cancer, rheumatoid arthritis, ulcers, diabetes, gastritis, fatigue, anemia, asthma, eczema, hemorrhoids, skin problems, body odour, constipation and even high blood pressure ^{4, 5}. Wheat (Triticum aestivum L.) belongs to family Gramineae. It is considered as important component of human diet, particularly in developing countries. Wheat germinated over a period of 9-10 days is generally called wheat grass. Thus, wheat grass refers to the young grass of common wheat plant. It is rich in chlorophyll, amino acids, minerals, vitamins and enzymes ⁶.

The aim of the present study is to evaluate the phytochemicals, reducing power, antioxidant activity and in – vitro lipid peroxidative capacity of wheat grass juice.

MATERIALS AND METHODS:

Preparation of wheat grass juice:

25grams of wheat grains were allowed to germinate for a period of 9 days in soil, under normal conditions. On 10^th day the green leaves obtained were collected. The wheat grass juice was obtained by crushing the green leaves in 100 ml of double distilled water and subjected to double filtration in order to collect the fresh filtrate for use and remove uncrushed insoluble matter. The fresh filtrate was further diluted with distilled water so as to obtain a concentration of 250 μg/ml and the various aliquots were used for the further experiments as wheat grass juice.

Phytochemical analysis:

The wheat grass juice was subjected to preliminary phytochemical analysis of total phenolic compounds, flavonoids, flavonols by methods described earlier by the authors Padmanabhan and Jangle; 2012 ^{7 “a”} . The DPPH ,nitric oxide and hydroxyl radical scavenging activity The total antioxidant activity by FRAP assay, reducing property was determined, by the methods described by authors Padmanabhan and Jangle; 2012 ^{7 “b”}. The anti lipid peroxidation of wheat grass juice was carried out in mouse liver as well as in brain homogenate of D-galactosamine induced hepatic damage (Padmanabhan and Jangle ;2014) ⁸ The 10% liver homogenate was centrifuged at 3000 rpm for 10 minutes and the supernatant obtained was used. 0.5 ml of the supernatant obtained from liver homogenate was added to 0.5 ml saline in a series of test tubes to which wheat grass juice was added in concentration ranging from 50μg/ml to 250μg/ml. The mixture was incubated for 15 minutes at 37°C. 10% trichloroacetic acid was added to stop the reaction.

The tubes were centrifuged at 3000 rpm for 20 minutes and the entire supernatant obtained was treated with 0.25 ml 1% thiobarbituric acid in 0.2 N NaOH. Further, the tubes were subjected to boiling for one hour at 95˚C. Thereafter the tubes were cooled to room temperature. The absorbances were measured on spectrophotometer at 532 nm. TBARS were estimated by the method of Fraga et al (1984)⁹. The 10% brain homogenate in phosphate buffer pH 7.4 was centrifuged at 3000 rpm for 10 minutes and the supernatant was used. 0.25 ml of supernatant of brain homogenate was taken in a series of test tube to which wheat grass juice was added in a concentration range of 50μg/ml to 250μg/ml. Further 0.05 ml of 15mM ferrous ammonium sulphate was added to enhance lipid peroxidation. All the test tubes were incubated for 30 minutes at 37˚C in a water bath.1 ml of 10% trichloroacetic acid was added and centrifuged for 20 minutes at 3000rpm. The entire supernatant obtained in each test tubes were treated with 1 ml of 0.8g/dl thiobarbituric acid and kept at 100˚ C for 20 minutes. The test tubes were allowed to cooled and thereafter centrifuged and the absorbances of the supernatants were measured on spectrophotometer at 530 nm.

RESULTS:

TABLE 1: PHYTOCHEMICAL ANALYSIS

Sr.no	Phytochemical	Mean ± SD
1.	Total phenolic compounds μM of gallic acid equivalent /g of wheat grass	301.74 ± 13.76
2.	Flavonoids mg rutin equivalent /g of wheat grass	10.29 ± 4.57
3.	Flavonols mg rutin equivalent /g of wheat grass	0.44 ± 0.08