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Domestication of Wheat

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Another crop of the utmost importance, for the present and the future population, is wheat (Triticum spp.). There are two main types of ancient domesticated wheat: the Einkorn (Triticum monococcum ssp. monococcum) and the Emmer (T. turgidum ssp. dicoccum L). They got replaced by a tetraploid free-threshing wheat (Durum Wheat) that evolved from the Emmer Wheat, that throuhout time give place to the common wheat (Triticum aestivum) we know today (Faris, 2014). There are 3 main genes involved in this crop domestication: Br (Brittle rachis), Q (free-threshing), and Tg (Tenacious glume) (Figure 1). In natural conditions, the seed dispersal is crucial for the dissemination of the species, a characteristic defined by brittle rachis (Br), but, for human use is not an advantageous strategy, because it difficult the harvesting process. This phenotype is controlled by a gene present in the 2A or 3A and 3B (depending on the species) chromosome, so a mutation must have occurred there to give ri...

Why is it important to study the metabolic pathways of plants ?

Knowledge of metabolic pathways and the analysis of differences between plants can be a great help in obtaining several products very useful for several areas related to the vegetal component of biology as is the case of Agriculture. One such case is the use of herbicides that block the synthesis of lipids at the level of ACCase (enzyme acetyl-CoA carboxylase) in grasses. This type of herbicide allows the absence of competition in the production of dicotyledons and some monocotyledons since these are not as affected as grasses. ACCase catalyzes the passage of acetyl-CoA to malonyl-CoA in the lipid synthesis pathway. And this selectivity is due to the fact that there are two types of ACCase enzymes. The eukaryotic ACCase, present in the cytoplasm, and the prokaryotic ACCase, present in the chloroplast. Since the synthesis of fatty acids in dicots occurs in chloroplasts and the form that is inhibited by the herbicide is the eukaryotic form, the synthesis of lipids in the dicotyledon...

Secondary metabolites of Plants

Secondary metabolites are chemical compounds produced only by certain organisms (mostly plant) and in certain circumstances (each species / genus produces a set of metabolites of its own). Having a very important role in the well-being of the organism that produces it, for example, the level of biotic stresses for protection against herbivores and the abiotic level in response to environmental changes. Among the various types of secondary metabolites are, for example, those containing nitrogen in the ring, such as Alkaloids; those composed mainly of carbon and hydrogen, such as terpenoids; and the phenolic compounds, which contain at least one aromatic ring and a hydroxyl group.  Alkaloids  can be derived from a variety of sources, such as lysine, ornithine, tyrosine, and tryptophan. Depending on the origin, several types of alkaloids are formed: Quinoleic alkaloids such as quinine, Pyridine alkaloids like nicotine, and isoquinoleic alkaloids such as morphine. ...

How can the secondary metabolites help the plant that produce them ?

Plants face huge daily risks to their existence. These range from large animals and herbivorous insects to fungi and microbes; and abiotically can be debated with drought and excess solar radiation for example. The secondary metabolites may exert several roles in the host plant, the defense metabolism being unquestionable. The defense metabolites may be stored in the plant in their inactive form (phytoerycipins) or, they are only produced when the plant is attacked (phytoalexins). Among the 3 main categories of secondary metabolites are highlighted some compounds and their function. From the Terpenos family, Monoterpenoids and Sesquiterpenoids are the main constituents of essential oils that can be toxic to insects and also serve as protection against fungal and bacterial attacks. For example, pine trees have alpha and beta pinellas that function as insect repellents; also Chrysanthemum Pyrethrins work with insect neurotoxins. Tannins and Anthocyanins are examples of Phenolic Compo...

Pharmacological effects of ginseng in the immune system

The pharmacological effects of ginseng  are mostly used therapeutically, ie, metabolites (such as ginsenosides) that affect a living system in order to treat a certain condition. There are several applications of ginsenosides in treatments of diseases and human conditions. Among them are anticancer effects, antidiabetics, antioxidants, among many others.  Here are some areas where ginseng exerts its positive effects: Immunity system Also certain activities of the immune system benefit from the presence of pharmacological compounds of ginseng (Kim et al ., 2013), such as phagocytic, antibacterial and antiviral. Macrophages increase phagocytic activity and nitric oxide production (NO), produced to destroy phagocytized organisms / compounds, in the presence of ginseng extracts (Shin et al ., 2002). Some Ginseng polysaccharides, such as PG-F2 and PG-HMV, are able to prevent the infectious process by microbes by disrupting their cell adhesion process (Lee et al...

Pharmacological effects of ginseng on Cancer

The pharmacological effects of ginseng  are mostly used therapeutically, ie, metabolites (such as ginsenosides) that affect a living system in order to treat a certain condition. There are several applications of ginsenosides in treatments of diseases and human conditions. Among them are anticancer effects, antidiabetics, antioxidants, among many others.  Here are some areas where ginseng exerts its positive effects: Cancer There are 3 basic advantages inherent in ginseng regarding cancer and its treatment. Ginseng helps prevent cancer, the growth of cancer cells, inhibits the creation of metastases and reduces the side effects of chemotherapy. Prevention of Cancer and Inhibition of Growth of Cancer Cells - It has been found that ginsenosides Rg3 and Rg5 demonstrate the greatest preventative ability relative to cancer cells. One explanation for this is that attenuation of lipid peroxidation and the ability to scavenge super oxide. It has also been sho...

Pharmacological effects of Ginseng in the Liver and Diabetes

The pharmacological effects of ginseng are mostly used therapeutically, ie, metabolites (such as ginsenosides) that affect a living system in order to treat a certain condition. There are several applications of ginsenosides in treatments of diseases and human conditions. Among them are anticancer effects, antidiabetics, antioxidants, among many others.  Here are some areas where ginseng exerts its positive effects: Liver In this organ ginseng has impacts in the fight against diseases caused by hepatotoxic agents and hepatitis. In the first case, the simple use of ginseng extracts with dietary honey can exert a synergetic effect to combat this type of diseases. The use of high doses of Paracetamol can lead to liver damage due to the effect of cytochrome P450 2E1 on acetaminophen (paracetamol), which converts it to N-acetyl-p-benzoquinone (hepatotoxin). Ginseng exerts a hepatoprotective effect due to Rg3 that inhibits the cytochrome in question (El Denshary et ...