The role of anthocyanins in senescing leaves of red-osier dogwood.
Adenosine triphosphate: Energy, in photosynthesis ATP is synthesized from the thylakoid membrane (sites of the photochemical reactions of photosynthesis), in Respiration ATP Respiration is the physical and chemical processes by which an organism supplies its cells and tissues with the oxygen needed for metabolism and relieves them of the carbon dioxide formed in energy-producing reactions.
01/06/2000 · Functional role of anthocyanins in ..
Bioactive principles of medicinal and toxicological significance: Bioactive principles, also referred as plant secondary metabolites, are derived from the products of plant primary metabolites, which are associated with the process of photosynthesis viz.; carbohydrates, s and simple lipids ().
Anthocyanins: The anthocyanins are the most important and widespread group of colouring matters in plants. These intensely coloured water soluble pigments are responsible for almost all the colours of petals, leaves and fruits of plants. Anthocyanins are basically composed of the aromatic rings of the cyanidin, from which several derivatives are generated by divergent insertions and positioning of substituents such as hydroxyl, methyl or glycosyl groups (-). Also, the molecular features of anthocyanins such as position, number and type of substitutions on the cyaniding backbone dictates the level to which anthocyanins exert their bioactive properties as well as the intracellular localization of the pigments (; ).
Anthocyanins have an antioxidant role ..
Selection of plant species: A review of literatures involving research on s suggests that scientist follow more or less the same general strategy to investigate plant materials for their pharmacological properties (; ). Plant species and plant part collected randomly are investigated using available phytochemical methods. However, a more targeted approach is often preferred to random selection (; ; ). Plant materials to be investigated are selected on the basis of some specific traditional uses; the so-called ethno-botanical bio-prospecting approach. s used for traditional remedies for certain diseases are more likely to contain biologically active principles of medicinal interest (; ; ). Alternatively, the plant can be selected based on chemo-taxonomical data. In the chemo-taxonomical approach, pre-knowledge that a particular group of plants contain certain classes of natural products may be used to predict that taxonomically related plant may contain structurally similar biomolecules (). Plant species may be selected based on field observations. For instance, plant species that thrive in hostile environment replete with bacteria, fungi or virus synthesize defensive natural products against these pathogens, which may also exhibit bactericidal, fungicidal or virucidal activity in human system.
What is the role of carotene and xanthophyll in photosynthesis
The renewed interest in natural products research, in recent years, has led to the development of new drugs, such as the anti-cancer chemotherapies- paclitaxel (Taxol) from the Pacific Northwest, Nutt. and the analogue, docetaxel, Vinca alkaloids vinblastine and vincristine, isolated from the Madagascar periwinkle, (L.) G. Don., etoposide and teniposide, isolated from roots of species; in addition to other drugs derived from natural products, which account for over 40% of new registered drugs (; ; ). Furthermore, earlier survey showed that about 70-80% of Asian and African populations rely on herbal remedies for their primary health care needs (; ); gave mankind artemisinin; the current WHO recommended anti-malarial agent (). The earliest anti-malarial agent-quinine was obtained from bark that dates back to 1638 (; ). Aside the therapeutic usefulness of bioactive principles, plants extracts are used as agrochemicals, flavor and fragrance ingredients, food additives and pesticides (; ). Many databases are available to describe the complete pharmacophore analysis of active principles possessing anti-diabetic, anti-microbial, anti-cancerous and anti-oxidant properties from s (). The present review highlighted the chemical diversity and medicinal potentials of bioactive principles as well inherent toxicity concerns associated with the use of these plant products, which are of relevance to the clinician, pharmacist or toxicologist.
Why Leaves Turn Red in Autumn. The Role of Anthocyanins …
During the fall, deciduous plants will decrease their levels of photosynthesis in response to reduced hours of sunlight per day and the amount of chlorophyll present will decline.