Identification of chlorophyll molecules with peroxyl radical scavenger capacity in microalgae Phormidium autumnale using ultrasound-assisted extraction.

The identification of chlorophyll molecules with peroxyl radical scavenger capacity in microalgae Phormidium autumnale was determined. The ultrasound-assisted extraction was utilized for obtaining the chlorophyll compounds from biomass. A total of eleven molecules were separated in microalgae chlorophyll extract, with pheophytin a' (371µg·g-1) and chlorophyll a (159.3µg·g-1) as the major ones. The chlorophyll extract was shown to be a potent scavenger of peroxyl radical, being almost 200 times more potent than α-tocopherol. These facts suggest the microalgae Phormidium autumnale as potential source of bioactive tetrapyrrole compounds.

Chemical constiuents from Richardia grandiflora (Cham. & Schltdl.) Steud. (Rubiaceae) / Constituintes químicos de Richardia grandiflora (Cham. & Schltdl.) Steud. (Rubiaceae)

Amongst the different forms of therapy to prevent and cure illnesses, plants have been, undoubtedly, the most utilized ones since the beginning of mankind. Brazil has a great diversity on plants that possess non-researched medicinal potential and are promising sources of therapeutic and pharmacological innovations. The Rubiaceae family is considered the biggest one of the order Gentianales, presenting around 637 genera and 10,700 species. Richardia grandiflora (Cham. & Schltdl.) Steud., known popularly as "ervanço", "poaia" or "ipeca-mirim", has ethnopharmacological indications to use as decoction against hemorrhoids and as vermifuge. Aiming at contributing to the chemotaxonomic study of the family Rubiaceae and considering the absence of data in literature about the chemical constitution of the species Richardia grandiflora, the latter was submitted to a phytochemical study to isolate its chemical constituents, through usual chromatographic methods, and after identifying them by means of spectroscopic methods such as ÕH and 13C NMR, with the add of two-dimensional techniques, besides comparison with literature data. Five constituents were isolated through this first phytochemical study with R. grandiflora: a mixture of the steroids beta-sitosterol and stigmasterol, o-hydroxy-benzoic acid, m-methoxy-p-hydroxy-benzoic acid and phaeophitin A, all of them isolated for the first time from the genus Richardia.

Dentre as diversas formas de terapia para a prevenção e cura de doenças, as plantas foram, indubitavelmente, as mais amplamente utilizadas desde o início da humanidade. O Brasil tem grande diversidade de plantas com potenciais medicinais, ainda não pesquisados, e que são promissoras fontes de inovações terapêuticas e farmacológicas. A família Rubiaceae, considerada a maior da ordem Gentianales, possui cerca de 637 gêneros e 10.700 espécies. Richardia grandiflora (Cham. & Schltdl.) Steud., conhecida popularmente como ervanço, poaia ou ipeca-mirim, tem indicações etnofarmacológicas para uso contra hemorróidas e como vermífugo na forma de decocto. Visando a contribuir com o estudo quimiotaxonômico da família Rubiaceae e tendo em vista a ausência de dados na literatura acerca da constituição química de Richardia grandiflora, esta foi submetida a um estudo fitoquímico para o isolamento de seus constituintes químicos, através dos métodos cromatográficos usuais, e posterior identificação estrutural dos mesmos, utilizando-se os métodos espectroscópicos de RMN ÕH e 13C uni e bidimensionais, além de comparações com modelos da literatura. Deste estudo pioneiro com R. grandiflora foram isolados e identificados cinco constituintes: uma mistura dos esteróides beta-sitosterol e estigmasterol, o ácido o-hidroxibenzóico, o ácido m-metoxi-p-hidroxi-benzóico e a feofitina A, todos inéditos no gênero Richardia.