Xanthosoma sagittifolium and Laportea aestuans: Species used to prevent osteoporosis in Brazilian traditional medicine

Abstract

Context: Xanthosoma sagittifolium Schott. (Araceae) and Laportea aestuans (L.) Chew (Urticaceae) are two medicinal species used as food and to prevent and treat bone diseases, such as osteoporosis, in traditional Brazilian medicine. Objective: To investigate the free calcium concentration and further support the traditional use of these species as medicine. Materials and methods: L. aestuans and X. sagittifolium leaves were dehydrated and cooked to evaluate the presence of free calcium. The total oxalate content was determined by heat digestion in H2SO4, oxalate precipitation with CaCl2 and permanganate titration. Results: The calcium content found in L. aestuans was quite significant (638.00 mg/100 g), whereas the fresh and cooked leaves of X. sagittifolium demonstrated a low content of calcium, at 273.17 and 369.81 mg/100 g, respectively. Discussion and conclusion: The use of this species for the prevention and treatment of bone diseases is in agreement with the results of the free calcium (Ca++) analyses. Our data show that each species may be used as a health supplement in poor communities, provided that studies validate their safe use. © 2012 Informa Healthcare USA, Inc.