In vitro propagation of two antidiabetic species known as guarumbo: Cecropia obtusifolia and Cecropia peltata

Two Cecropia species (Cecropia obtusifolia and C. peltata), known as guarumbo, are employed in Mexican traditional medicine to treat diabetes mellitus; the leaves of both species contain phenolic bioactive compounds such as chlorogenic acid (CA) and isoorientine (ISO), which have been attributed with hypoglycemic, hypolipidemic, and antioxidant properties. An in vitro propagation protocol was developed from existing apical bud meristem from C. obtusifolia seedlings; the shoot generation was induced on Murashige and Skoog (MS) medium supplemented with varying concentrations of 6-benzylaminopurine and kinetin (Kn) combined with either alpha-naphtalene acetic acid (NAA) or indole-3-acetic acid (IAA) auxins. Best morphogenetic response was developed with Kn 26.64 mu M combined with either NAA or IAA 0.57 mu M, respectively; likewise, C. peltata-seedling apical buds were subjected to these best selected treatments. Cecropia obtusifolia and C. peltata shoots were rooted in growth regulator-free half-strength MS medium, and regenerated whole plants were adapted successfully under greenhouse conditions and field. Leaves from both Cecropia-micropropagated plants produced the phenolic compounds CA and ISO, with highest concentrations in leaves from 18-month C. obtusifolia (12.28 +/- A 7.06 mg g(-1) dry leaves of CA and 8.30 +/- A 2.70 mg g(-1) dry leaves of ISO) growth in the field. Our results offer a protocol of apical-bud use for multiplication and curative-property conservation of the two previously mentioned important Mexican medicinal plants.