ANTIOXIDANT POTENTIAL AND MINERAL COMPOSITION OF TWO TEA INFUSIONS (Moringa oleifeira AND Glycyrrhiza glabra) AND THEIR BIOCHEMICAL EFFECT IN MALE ALBINO RATS

Abstract

Herbal formulations have been in use for many years globally as an excellent source of nutrients and antioxidant components. The use of various synthetic drugs revealed serious side effects, and a better strategy will be to look at natural substances with good pharmacological activity and less cytotoxicity. Moringa (Moringa oleifera) and Licorice (Glycyrrhza glabra) herb teas have been widely harnessed as folk medicine as anti-stress, anti-mutagenic, anti-diabetic and antibacterial. This research was carried out to characterize the phenolic composition of Moringa oleifera (M), Glycyrrhiza glabra (LR) and Moringa oleifera-Glycyrrhiza glabra (M+LR) hot water infusions, evaluate their antioxidant activities, mineral contents, neuro-protective potential, effects on liver markers and also conduct histological studies on specific tissues of the male rats after pre-treatment with the tea samples. Phytochemical screening revealed the presence of some phytochemicals such as saponins, flavonoids, tannin, terpenoids and alkaloids in both tea infusions. High performance liquid chromatography with diode array detector (HPLC-DAD) characterization of the tea samples revealed the presence of flavonoids (catechin, epicatechin, quercitrin, kaempferol, rutin and quercetin) in both samples, with caffeic acid, glycyrrhenitic acid and luteolin present only in Licorice, while chlorogenic acid, gallic acid and ellagic acid is present only in Moringa oleifera. Both tea infusions showed relatively good antioxidant activities with M+LR having the highest total phenol and total flavonoid content (97.87mg/g and 82.47mg/g) respectively. Moringa oleifera has the highest reducing power and hydroxyl radical scavenging activity (34.79mg/g and 61.55mg/g) respectively. Conversely, Licorice recorded the highest 2,2-diphenyl-1-picrylhydrzyl (DPPH) radical scavenging activity (44%), 2,2-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid (ABTS) radical scavenging activity (33937.5 μmol TE/g), and nitric oxide (NO) radical scavenging activity (49.51%). The tea infusions reduced lipid peroxidation with M+ LR demonstrating the highest inhibitory action in the brain (53.62%) and Moringa (72.72%) in the liver. The result of the neuroprotective assays revealed that M+LR possessed the highest acetylcholinesterase and butyrylcholinesterase inhibitory activity (77.57% and 45.89%) respectively while Moringa possessed the highest superoxide inhibitory activity (51.12%). The result of mineral analysis revealed that potassium is the most abundant mineral in the tea samples; composition of nickel was below the critical dose, while chromium and cadmium were totally absent. The result also revealed that zinc and calcium were bioavailable in the two studied tea infusions. The result of the effect of the tea infusions on liver markers such as alanine transaminase (ALT), aspartate transaminase (AST), lactate dehydrogenase (LDH), gamma glutamyltransferase (GGT), alkaline phosphatase (ALP), total protein (TP), albumin (ALB), total bilirubin (T.BIL) and glucose (GLU) revealed that the tea samples do not have any damaging effect on the liver, with the exception of licorice whose value was above the normal range for AST (60.67U/L), LDH (524.13U/L) and T.BIL (1.32mg/dl). Histology studies carried out on the liver revealed that the infusions do not have any damaging effects on the liver, with the exception of M+LR at 50mg/ml and Licorice at 50mg/ml that showed a damaging effect to the hepatocytes. The result also revealed Moringa as the best candidate from nutraceutical point of view, followed by M+LR. Therefore the two tea varieties are safe for consumption when consumed at regulated doses and could be useful in managing stress and stress-related diseases.