Chemical and Biological Characterization of Components from Aloe arborescens Miller with Biological Modifier Response

Abstract

The current context of research in the field of pharmacy is experiencing a shift towards natural medicine and thus to vegetal products with curative properties. The volume of scientific information in the field of phytopharmacy has doubled in the last decade, along with the improvement of the equipment and analytical methods necessary for such determination of the active principles in the plants. This ultra-fast development of investigation methods is sustained by extensive researches which seek new resources yet investigated. Although traditional medicine uses the full therapeutic potential of native plants that extremely common in the flora of our country, they are less valued at therapeutic level in the pharmaceutical industry. These species, if it is found to be rich in secondary metabolites and are widespread in indigenous flora can provide cheap alternative resources. The proposed species, A. arborescens is a plant grown and cultivated in East deserts, and its studies are extremely poor especially in our country. Where, there are no reports about either chemical characterization or biological activities. The plant is a member of the Asphodelacea family and considered as the most widely cultivated Aloe species in the world, being used in health & related products. It is native to South Africa; it has been imported from many countries in the tropics and subtropics as an ornamental and medicinal. The plant grows as a green-gray leaves, typically arranged in aesthetically pleasing rosettes, with off-white, characterized by teeth along the leaf margins. The plant flowers in the spring-summer months, putting off colorful flower spikes typically in a dark orange-to-red hue and sometimes even yellow and it typically grows into a multi-pronged shrub approximately 2-3 meters in height. In the review of current literature, it was found that studies of plant total extracts not clarify the relationship between chemical structures and reported anticancer activity. In addition, although the antitumor activity of anthraquinones from other Aloe species was investigated that of A. arborescens was not studied. Also the biological studies on main primary metabolite polysaccharides were limited. Thus it was deemed of interest to study the plant, aiming to investigate its antitumor mechanism of action taking in consideration the corresponding isolated constituents. Summary 191 Part I: Bio-guided fractionation of total extract Five different extracts separated from A. arborescens filet and exudates (NpQ, POQ, WAP, ACP, ALP) was assessed their cytotoxic effect against PC3, HepG2 and MCF-7 cell line. The results revealed that three fractions (NPQ, WAP and ALP) possessed the most cytotoxic activity on the liver carcinoma (HepG2). Also NPQ fraction showed an activity against (PC3) and (MCF-7). On the other hand, all polysaccharides fractions exhibited weak cytotoxic effect against PC3 and MCF7. Therefore; HepG2 considered as cancer cell line target for further analysis. The three bioactive extracts NPQ, WAP and ALP were selected for further analysis and identification of potential its bioactive components.