Nutritional and Phytochemical Properties of Aqueous Leaf Extract of Mistletoe (Tapinanthus Bangwensis) Grown on Orange Tree

Abstract

Background: African mistletoe (Tapinanthus bagwensis) is a parasitic plant commonly used in folk medicine. The bioconstituents and thus its nutritional and ethnomedicinal uses may be greatly affected by ecological interactions between the plant and host. Objectives: This study investigated the proximate and phytochemical compositions of aqueous leaf extract of Tapinanthus bangwensis grown on orange tree. Methods: Standard methods of the Association of Official Analytical Chemists (AOAC) was used to evaluate the proximate and mineral elements compositions of Tapinanthus bangwensis aqueous leaf extract. Vitamins content and presence of lectin was quantified using high performance liquid chromatography and via hemagglutinating activity respectively. Phytochemicals were determined using spot test and spectrophotometrically. Results: The proximate analysis revealed that T. bangwensis aqueous leaf extract contained total carbohydrate (12.72 ± 0.1 %), crude fat (9.65±0.3%), protein (6.8 ± 0.4%), ash (3.5 ± 0.1%), moisture (0.13 ± 0.2%) and crude fibre (67.2 ± 0.1%). The minerals (mg/ 100 g dry weight) present were K (147.3 ± 0.01) > Ca (90.70 ± 0.025) > P (62.9 ± 0.025) > Na (54.6 ± 0.03) > Mg (43.05 ± 0.02) > Mn (34.00 ± 0.01) > Zn (24.90 ± 0.015) > Iodine (2.05 ± 0.01). Vitamins A, D, B2, E, K, B12 and Folic acid were relatively abundant compared to other vitamins. The extract possessed lectin depicted by hemagglutination activity on different animal species’ blood samples. The phytochemicals (mg/100 g) concentration was tannin (108.65 ± 0.04), phenol (66.7 ± 0.01), flavonoid (44.58 ± 0.03), cyanogenic glycoside (24.53 ± 0.02) and saponin (2.40 ± 0.02). Conclusion: Given these nutritional, phytochemical constituents and their concentrations, T. bangwensis aqueous leaf extract could be a good nutrient source for consumers and might be beneficial in maintaining good health.