RESUMO
The new hexahydroazulenones hortonones A (1) to C (3) were isolated from the leaves of three representative species of the endemic Sri Lankan genus Hortonia that belongs to the family Monimiaceae. Hortonones A (1) and B (2) have the unprecedented rearranged hortonane sesquiterpenoid carbon skeleton, and hortonone C (3) has the unprecedented rearranged and degraded 13-norhortonane skeleton. Hortonone C (3) exhibited in vitro cytotoxicity against human breast cancer MCF-7 cells at 5 µg/mL.
Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Diterpenos/isolamento & purificação , Monimiaceae/química , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Neoplasias da Mama , Diterpenos/química , Diterpenos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Estrutura Molecular , Folhas de Planta/química , Sri LankaRESUMO
Temperature-induced mineral alterations are extensively used in traditional pharmaceutical industry. Studies on the traditional heating methods for enhancing pharmaceutical properties and on the toxicity of mineral-based medicines are limited. This study focuses on the effect of thermal alterations on mineralogical and chemical changes of biotite with respect to two traditional drugs (Abhrak Bhasma and Abhrak Chendhuram). Samples of the drugs and heat-treated and untreated biotite minerals were characterized using X-ray diffraction analysis, Fourier-transform infra-red spectroscopy, thermogravimetric analysis and differential scanning calorimetry. Total and water-soluble cation concentrations of drugs were measured using atomic absorption spectrometry. The study reveals that the degree of collapsing the biotite structure increased with the thermal oxidation process that produced nanoparticles of crystalline and amorphous iron oxides and secondary silicates. The thermal products of biotite had nano-crystallinity and high water solubility. The study suggests that modern pharmaceuticals can be developed from mineral-based traditional drugs.
RESUMO
ETHNOPHARMOCOLOGICAL RELEVANCE: Biotite mica enriched with Fe(2+) ions are widely used as a major mineral ingredient in traditional pharmaceutical science of alchemy (Rasashastra). Abhrak bhasma (mica ash), a pharmaceutical product containing treated mica, is utilized, for example, in Ayurvedic treatments for ailments such as gastritis, renal disease, skin disease and mainly in rejuvenation formulations. However, the untreated mica minerals may be harmful when used directly, as they carry considerably high amounts of trace-elements that can cause undesirable effects in the human body. In order to remove toxic factors and produce readily absorbable materials having high nutrient capacity, specific thermal and chemical treatments (purification, detoxification, particle size reduction and incineration) are performed during the preparation of Rasashastra. This review evaluates the chemical and pharmacological aspects of mica ash as well as the technological aspects of mica ash production. MATERIALS AND METHODS: The detailed literature review on the chemistry and scientific basis of mica ash, its preparation techniques, mica alterations and pharmaceutical applications was carried out by using published Ayurvedic text books and research articles, available from Science Direct, on mica minerals, mica ash and their physico-chemical alteration processes and pharmacological applications. RESULTS: During the purification and detoxification procedures, heating followed by quenching (in ionic medium) influences the structural distortion and the development of stress-induced cracks and spallations of the micaceous plates. Thus, the efficient diffusion of the external medium takes place at successive heating and quenching steps. Acidic organic liquids and animal byproducts can enhance the cation exchange capacity and solubility of mica. Further, these natural compounds facilitate the removal of toxic-elements in the structure. When treated-mica and paddy husks are tied up in a cloth and squeezed, particle size reduction and further detoxification takes place. Leaching out of oxidized iron coatings is accelerated when the mixtures are immersed in acidic media, by which the filtrate is enriched with oxidized iron-silicate particles. These nano-oxide particles are converted into a more favorable oxidation form for human consumption when the herbometallic mixture is incinerated in closed vessels. Recent analytical data reveals that major and minor elements in mica ash are within the limits of pharmacopoeial standards for Ayurvedic formulations. Further, recent studies show that mica ash has hypoglycemic, hepatoprotective, anthelminthic and antimicrobial properties. CONCLUSIONS: Chemical and structural modifications in mica occur during mica-based drug preparation in traditional medicine. Purification steps particularly influence the structural distortion while heating and quenching can form nano-size particles. Carboxylic acids and other organic molecules present in quenching media serve as chemical modifiers of mica. At the same time the toxic elements are leached out from mica to the quenching media through an ion exchange process. Mica ash has been successfully used for treating liver, kidney and skin related ailments in traditional medicine, and mica ash alone or its herbo-metallic formulations have different applications. Further, the recent toxicological and analytical studies validate the traditional uses of mica ash and mica ash bearing products. Further scientific studies are needed to fully establish that mica-based pharmaceuticals are safe and devoid of toxic and long term side effects.