Research of Nutritional Value and Safety Evaluation of Tetrastigma hemsleyanum Leaves

To scientifically evaluate the nutritional value and edible safety of Tetrastigma hemsleyanum leaves and provide a scientific basis for developing them as novel food ingredients, the nutritional composition, edible toxicity and genotoxicity were analyzed and compared with those of tea(Camellia sinensis) leaves, chrysanthemum (Chrysanthemum × morifolium), and ginkgo (Ginkgo biloba) leaves. The results showed that the ratio of free amino acid in T. hemsleyanum leaves was 4.5%, significantly higher than those in tea and ginkgo leaves (P<0.05), and approximately 6 times that of chrysanthemum. The iron content was 80.9 mg·kg⁻¹, significantly higher than those in tea and ginkgo leaves (P<0.05). The zinc content was 17.8 mg·kg⁻¹, 4～12 times higher than those in tea, chrysanthemum and ginkgo leaves. The selenium content was 0.143 mg·kg⁻¹, more than 9 times those in tea, chrysanthemum and ginkgo leaves. The contents of vitamin C and vitamin E reached mg·100 g⁻¹ and 46 mg·100 g⁻¹, respectively, both significantly higher than those in tea, chrysanthemum and ginkgo leaves. Acute oral toxicity tests indicated that T. hemsleyanum leaves were practically non-toxic. Micronucleus and chromosomal aberration tests demonstrated that T. hemsleyanum leaves exhibited no teratogenicity or genotoxicity. Bacterial reverse mutation assay showed that T. hemsleyanum leaves possessed no carcinogenicity. In conclusion, T. hemsleyanum leaves possess the safety attributes and nutritional value suitable for development as new food raw material.