Phytochemical screening, antioxidant activity and toxicity of the orchids Prosthechea cochleata and Prosthechea livida-A preliminary study

Phytochemical composition, antioxidant, and toxic effects of two orchid (Prosthechea cochleata and Prosthechea livida) were examined in their different hexane and dichloromethane/methanol extracts of leaves, pseudobulbs, rhizome and roots.  Phytochemical screening reveals the presence of alkaloids, coumarins, flavonoids, saponins, steroids and terpenes except for anthracene derivatives in P. livida and tannins in both species. Results showed exhibited significant toxicity against brine shrimp with an LC50 values ranged from 3 to 54 µg/ml in 24 h.  Finally, the results of the antioxidant test in yeast (Saccharomyces cerevisiae) showed that CH2Cl2:MeOH extract of P. cochleata root extract presented the most efficient protective antioxidant percentage (%PA), with 20 µg/mL, displaying a cell viability of 68.58%. In P. livida case, rhizome extract presented the most efficient %PA, with 1000 µg/mL, with a cell viability of 65.82%.  The results evidenced the toxicity of  Prosthechea cochleata and Prosthechea livida and reveals potential antioxidative of extracts

Report of a floral visitor of Cypripedium irapeanum (Orchidaceae) in Tepoztlán, Morelos, Mexico

The process and participating actors of pollination have fascinated many scholars since the time of Darwin. Nevertheless, for many species of orchids, the identity of the pollinator or the purpose of floral visits remains unknown. Cypripedium (Orchidaceae) is a genus of worldwide distribution that presents a broad range of colors and sizes. Three species are reported in Mexico: C. dickinsonianum, C. irapeanum and C. molle. However, there is very little information regarding the ecological interactions of these species. Firstly, a preliminary bibliographic review was conducted in order to compile information pertaining to the pollinators and floral visitors of the genus Cypripedium. Secondly, a population of C. irapeanum was monitored in a pine-oak forest at 1680 m.a.s.l. in the municipality of Tepoztlán, in Morelos, Mexico. The municipality of Tepoztlán in Morelos, Mexico, hosts a population of approximately 250 individuals of the species C. irapeanum. During a visit to this site in July 2015, two specimens of bees, belonging to the genus Lasioglossum subgenus Eickwortia, were found exiting from the apertures of the rear part of the C. irapeanum labellum. This event was photographed and one bee specimen was collected and identified to species, thus contributing to the first record of a floral visitor to this species of orchid. Lasioglossum nyctere is a floral visitor and possibly a pollinator of C. irapeanum. Future studies should confirm whether or not this bee is indeed a pollinator of the orchid

Potential distribution of six endemic species of Stanhopea (Orchidaceae) genus in Mexico

Stanhopea is an orchid’s genus that includes 55 species distributed from Mexico to Argentina. However, due to its horticultural potential, a decrease in wild populations has been generated by the effect of over-collecting, further aggravated by the effect of habitat destruction, placing some species of Stanhopea from Mexico in some risk categories. In this work, the potential distribution areas of six endemic Stanhopea species in Mexico and in some Federal Natural Protected Area (ANP) were modeled with the use of the MaxEnt software. The potential distribution of the six endemic species in Mexico was obtained, in addition to the fact that it is possible to find one or more species within 74 ANPs