Plants flavonoid-deficient

The first nucleotide sequence for CHS was determined from cultured parsley cells [53]. Since then, its expression and regulation have been extensively studied in numerous plant systems in relation to a myriad of different conditions and stimuli [e.g., 21 and ref therein]. Due to its key role in flavonoid biosynthesis, CHS has been a popular target for various gene-silencing techniques in attempts to generate flavonoid-deficient plants [16, 54 and ref therein]. 

M., AUSUBEL, F.M., GOODMAN, H., Analysis of Arabidopsis mutants deficient in flavonoid biosynthesis, Plant J., 1995, 8, 659-671. 

Ormrod, D.P., Landry, L.G., and Conklin, P.L., Short-term UV-B radiation and ozone exposure effects on aromatic secondary metabolite accumulation and shoot growth of flavonoid-deficient Arabidopsis mutants, Physiol Plant., 93, 602, 1995. 

In this review, the phytochemical studies found in the scientific literature for the plants included in Table 2, with possible hypnotic effects, also showed a prevalence of the flavonoid and essential oil, as shown in plants in Table 1, with possible anxiolytic effects, as can be seen in Fig. (4). These results emphasize the importance of these constituents in the treatment of diseases related to some deficiencies of the CNS, once more followed by the phenolic acids and alkaloids as shown in Fig. (4). These substances may act producing two effects, both as anxiolytics and as hypnotics, the difference being only in the dosage of the drug, as formerly cited. 

Most flavone and flavonol glycosides are not particularly toxic to man or other higher animals (McClure, 1975). One compound of this type, rutin (35), was once considered to be a vitamin, but is generally not at present (Harbome, 1991). Compounds of this general structure may be required in the human diet, but it is difficult to imagine anyone suffering from such a deficiency, as flavonoids are found in most of the plant materials that we eat. 

Lau, T.S.L., Eno, E., Goldstein, G., Smith, C. Christopher, D.A. (2006). Ambient levels of UV-B in Hawaii combined with nutrient deficiency decrease photosynthesis in near-isogenic maize lines varying in leaf flavonoids flavonoids decrease photoinhibition in plants exposed to UV-B. Photosynthetica, 44, 394-403. 

Phenolic compounds present in natural products include simple phenols, phenolic acids, tocopherols, stilbenes, coumarins, flavonoids (flavonol, flavones, flavanols, antho-cyanidins, proanthocyanidins), tannins, lignans, and lignins (Naczk and Shahidi, 2006 Folmer et ah, 2014). Phenolic compounds are secondary plant metabolites that are synthesized in response to stress conditions, such as UV irradiation, nutrient deficiencies, infection, and wounding (Naczk and Shahidi, 2006 Ramakrishna and Ravishankar, 2011). 

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