Martim Silvia Aparecida
Departamento de Ciencias Fisiologicas, Instituto de Biologia, Universidade Federal Rural do Rio de Janeiro, BR 467 km 7, 23890-000, Seropedica, Rio de Janeiro, Brazil.
Recent Pat Biotechnol. 2014;8(1):36-46. doi: 10.2174/1872208307666131218125553.
The use of plants for healing diseases is one of the oldest medical practices and there are several studies showing that botany and medicine are related. Recent researches have shown that around 25% of new chemical entities and 42% of anticancer drugs marketed worldwide from 1981 to 2006 are obtained from natural products and their derivatives. One-third of the botanical biodiversity of the planet is in South American tropical ecosystems (Neotropical). Over the centuries, plants have been used by indigenous people for curing diseases. This strong tradition has been a great challenge for the scientific community in order to validate the folkloric medicinal use of herbs. In this way, a very few Neotropical pharmaceutical products have reached the market in industrialized countries, even though they have a considerable plant diversity. Plants synthesize several organic compounds which are not related to their growth and development and are called secondary metabolites or natural products that are derived from central or primary metabolism. Because plants are sessile organisms, they have to respond quickly to environmental changes in order to escape and survive under unfavorable conditions. Drought is one of the most worldwide serious impediments for crop yields producing adverse negative effects on plant growth, by impacting leaves and roots growth, stomatal conductance, photosynthetic rate and biomass gain. The three major classes of secondary metabolites are produced from pathways of different primary metabolites, including glycolysis, tricarboxilic acid cycle, aliphatic amino acids, pentose phosphate pathway, shikimate pathway and aromatic amino acids. This review compiles the metabolic changes occurring at primary metabolite level and total biosynthesis of natural products with potential for the development of new drugs in response to drought.
利用植物治疗疾病是最古老的医疗实践之一，有多项研究表明植物学与医学相关。最近的研究表明，1981年至2006年全球上市的新化学实体中约25%以及抗癌药物中42%都源自天然产物及其衍生物。地球上三分之一的植物生物多样性存在于南美热带生态系统（新热带地区）。几个世纪以来，当地居民一直使用植物来治疗疾病。为了验证草药在民间医学中的用途，这一悠久传统给科学界带来了巨大挑战。因此，尽管新热带地区有丰富的植物多样性，但在工业化国家只有极少数该地区的医药产品进入市场。植物合成多种与其生长发育无关的有机化合物，这些化合物被称为次生代谢产物或天然产物，它们源自中心代谢或初级代谢。由于植物是固着生物，它们必须迅速应对环境变化，以便在不利条件下逃避和生存。干旱是全球范围内对作物产量最严重的阻碍之一，它通过影响叶片和根系生长、气孔导度、光合速率和生物量积累，对植物生长产生不利的负面影响。三大类次生代谢产物由不同初级代谢产物的途径产生，包括糖酵解、三羧酸循环、脂肪族氨基酸、磷酸戊糖途径、莽草酸途径和芳香族氨基酸。本综述汇编了在初级代谢产物水平发生的代谢变化以及天然产物的总生物合成情况，这些天然产物具有开发应对干旱的新药的潜力。
