Oranges - Research:
Citrus fruits, including C. sinensis, have been investigated as a delivery system for vaccines; the fruits were injected with the vaccine and then eaten.9 Most modern research, however, is focused on new efficient ways to grow, protect and harvest oranges.
Almost 80% of oranges are used for orange juice. However, the juice and pulp have been used as a digestive aid, to relieve gas pains, swelling and constipation.2,5 Oranges also contain vitamins A, B-complex and C, flavonoids and antioxidants.2,6,7 The fruit also has a high folate content.8 The dried orange peel has been used to treat coughs and colds.5,7
Orange Peel: The essential oil extracted from the peel through either cold expression or steam distillation, has a sweet citrus aroma.7 The orange scent is a combination of lemon-scented citral and limonene, lavender-scented linalool and pine-scented terpineol. Topical applications of the essential oil are used to soften dull and oily complexions and soothe mouth ulcers.
References:
2 Onstad D. Whole Foods Companion: A Guide for Adventurous Cooks, Curious Shoppers & Lovers of Natural Foods. White River Junction, VT: Chelsea Green Publishing Company; 1996.
5 Wood R. The New Whole Foods Encyclopedia. New York: Penguin Books; 1999.
6 Rinzler C. The New Complete Book of Herbs, Spices, and Condiments: A Nutritional, Medical, and Culinary Guide. New York: Checkmark Books; 2001.
7 Lawless J. The Encyclopaedia of Essential Oils: The Complete Guide to the Use of Aromatics in Aromatherapy, Herbalism, Health & Well-being. Rockport, MA: Element; 1992.
8 Crowel PL, Gould MN. Chemoprevention and therapy of cander by d-limonene. Crit Rev Oncog. 1994; 5:1-22. Cited by Rakel, D. Integrative Medicine. Philadelphia: Saunders; 2003.
9 Hu R, Wei H, Chen S, et al. Construction of the plant expression vector with hepatitis a capsid protein fusion gene and genetic transformation of Citrus sinensis Osbeck[In Chinese]. Yi Chuan. July 2004; 26(4):425-31.