In Vitro Biosynthesis of Polyphenols in the Presence of Elicitors and Upregulation of Genes of the Phenylpropanoid Pathway in Plantago ovata
01 Jan 2019-Vol. 60, pp 299-344
TL;DR: In this paper, a review of the properties of polyphenols in callus culture of Plantago ovata is presented, which is an important medicinal plant and a rich source of secondary metabolites including polyphenolic compounds.
Abstract: Plantago ovata is an important medicinal plant and a rich source of secondary metabolites including polyphenolic compounds. In vitro callus culture of this plant opens up the possibility of photochemical prospecting with enhanced production of some polyphenols using elicitors. Utilizing the callus is advantageous as the whole plant need not be sacrificed. Subculturing results in an increase of callus biomass along with the most prized phytochemicals. The reservoir of polyphenolic compounds has been studied by various authors from time to time to extract polyphenols in general and some others that are unique to Plantago by HPLC analysis, such as trans-cinnamic acid, gallic acid, rutin, quercetin, catechin, luteolin-7-O-β- d glucoside, coumaric acid, vanillic acid, chlorogenic acid, trans-ferulic acid, and caffeic acid. Organic plant additives, such as casein hydrolysate, coconut water, and even plant growth regulators in different concentrations and combinations, have resulted in enhancing polyphenol and flavonoid biosynthesis during in vitro callus culture of this plant. Polyphenols, being natural products, result in higher antioxidant activity in subcultured calli. Epidemiological studies have shown that a human diet rich in polyphenols gives protection against several metabolic disorders, such as diabetes, cancer, and cardiovascular diseases. Polyphenols are intermediate products of the phenylpropanoid pathway and their production is regulated by differential expression of the genes of this pathway, such as phenylalanine ammonia lyase (PAL), chalcone synthase (CHS), and dihydroflavonol-4-reductase (DFR). Another important gene is polyphenol oxidase (PPO), which causes enzymatic browning by oxidation of phenolic compounds to O-quinone and polymerizes polyphenolic compounds. It is regarded as an antioxidative defense enzyme of plants. Critical quantitation of the organic chemicals that enhance the production of polyphenols will be dealt with in this review chapter in relation to PAL, CHS, DFR, and PPO. This will clarify biochemical regulation by using molecular biological techniques like reverse transcription and real-time PCR. Bioinformatic details on the structure prediction of these genes will also throw light on the upregulation of gene expression in relation to increased polyphenol biosynthesis.
TL;DR: In this article , the authors used Kundu phytohormones to regulate secondary metabolites synthesis in plant cells, and they used Murashige Skoog and Anderson agar media to find the optimal nutrient medium in order to obtain the maximum increase in polyphenolic compounds.
Abstract: One of the ways to design polyfunctional ingredients that determine the functional properties of food products are complex food additives consisting of valuable plant raw materials. The additives quality depends on the used raw materials adequacy, time and collection place, and the plant cultivation conditions. The traditional plantation method requires significant costs to obtain secondary metabolites determining physiological plant materials value. The research aim is to obtain polyphenolic compounds from phyto-raw materials by microclonal cell propagation under sterile laboratory conditions. The leaves and berries cells of cowberries and cranberries containing a significant number of polyphenols are the research objects. For example, cranberries growing in the south of the Tyumen region contain anthocyanins 97.8 mg/100 g and leukoanthocyanins 459.6 mg/100 g, and berries growing in the Arctic territories of the Yamalo-Nenets Autonomous Okrug contain 224.7 and 480.2 mg/100 g, respectively. At the initial stage, the researchers sterilized objects, instruments, and equipment. They determined the sterilization duration experimentally. The study revealed that with a longer sterilization duration, there was a change in color and an increase in cell toxicity, with a minimum duration, pathogenic microorganisms remained in the medium. After sterilization, a man cultured the cells in the light under fluorescent lamps with illumination of 100 mmol quanta/m²; photoperiod of 20 h per day; in nutrient media with an acidity of pH 5.2–5.4; 25 ml in volume; enriched with the auxins and cytokinins hormones. The researchers used Kundu phytohormones to regulate the secondary metabolites synthesis. They utilized Murashige Skoog and Anderson agar media to find the optimal nutrient medium in order to obtain the maximum increase in polyphenolic compounds in plant cells. A man developed the third agar media independently, considering the prospects of an individual approach to the more efficient producers growth.
TL;DR: A new criterion for triggering the extension of word hits, combined with a new heuristic for generating gapped alignments, yields a gapped BLAST program that runs at approximately three times the speed of the original.
Abstract: The BLAST programs are widely used tools for searching protein and DNA databases for sequence similarities. For protein comparisons, a variety of definitional, algorithmic and statistical refinements described here permits the execution time of the BLAST programs to be decreased substantially while enhancing their sensitivity to weak similarities. A new criterion for triggering the extension of word hits, combined with a new heuristic for generating gapped alignments, yields a gapped BLAST program that runs at approximately three times the speed of the original. In addition, a method is introduced for automatically combining statistically significant alignments produced by BLAST into a position-specific score matrix, and searching the database using this matrix. The resulting Position-Specific Iterated BLAST (PSIBLAST) program runs at approximately the same speed per iteration as gapped BLAST, but in many cases is much more sensitive to weak but biologically relevant sequence similarities. PSI-BLAST is used to uncover several new and interesting members of the BRCT superfamily.
TL;DR: In vivo redox biosensing resolves the spatiotemporal dynamics of compartmental responses to local ROS generation and provide a basis for understanding how compartment-specific redox dynamics may operate in retrograde signaling and stress 67 acclimation in plants.
Abstract: In experiments with tobacco tissue cultured on White's modified medium (basal meditmi hi Tnhles 1 and 2) supplemenk'd with kiticthi and hidoleacctic acid, a slrikin^' fourlo (ive-told intTease iu yield was ohtaitu-d within a three to Tour week j^rowth period on addition of an aqtteotis exlrarl of tobacco leaves (Fi^'ures 1 and 2). Subse(iueutly it was found Ihiit this jnoniotiou oi' f^rowih was due mainly though nol entirely to inorj^auic rather than organic con.stitttenls in the extract. In the isolation of Rrowth factors from plant tissues and other sources inorj '̂anic salts are fre(|uently carried along with fhe organic fraclioits. When tissue cultures are used for bioassays, therefore, il is necessary lo lake into account increases in growth which may result from nutrient elements or other known constituents of the medium which may he present in the te.st materials. To minimize interference trom rontaminaitis of this type, an altempt has heen made to de\\eh)p a nieditmi with such adequate supplies of all re(iuired tnineral nutrients and cotntnott orgattic cottslitueitls that no apprecial»le change in growth rate or yield will result from the inlroduclion of additional amounts in the range ordinarily expected to be present in tnaterials to be assayed. As a point of referetice for this work some of the culture media in mc)st common current use will he cotisidered briefly. For ease of comparis4)n Iheir mineral compositions are listed in Tables 1 and 2. White's nutrient .solution, designed originally for excised root cultures, was based on Uspeuski and Uspetiskaia's medium for algae and Trelease and Trelease's micronutrieni solution. This medium also was employed successfully in the original cttltivation of callus from the tobacco Iiybrid Nicotiana gtauca x A', tanijadorffii, atitl as further modified by White in 194̂ ^ and by others it has been used for the
TL;DR: A computer program that progressively evaluates the hydrophilicity and hydrophobicity of a protein along its amino acid sequence has been devised and its simplicity and its graphic nature make it a very useful tool for the evaluation of protein structures.
TL;DR: The factors underlying the influence of the different classes of polyphenols in enhancing their resistance to oxidation are discussed and support the contention that the partition coefficients of the flavonoids as well as their rates of reaction with the relevant radicals define the antioxidant activities in the lipophilic phase.
TL;DR: SignalP 4.0 was the best signal-peptide predictor for all three organism types but was not in all cases as good as SignalP 3.0 according to cleavage-site sensitivity or signal- peptide correlation when there are no transmembrane proteins present.
Abstract: We benchmarked SignalP 4.0 against SignalP 3.0 and ten other signal peptide prediction algorithms (Fig. 1). We compared prediction performance using the Matthews correlation coefficient16, for which each sequence was counted as a true or false positive or negative. To test SignalP 4.0 performance, we did not use data that had been used in training the networks or selecting the optimal architecture, and the test data did not contain homologs to the training and optimization data (Supplementary Methods). The test set for SignalP 3.0 was also independent of the training set because we removed sequences used to construct SignalP 3.0 and their homologs from the benchmark data. For other algorithms more recent than SignalP 3.0, the benchmark data may include data used to train the methods, possibly leading to slight overestimations of their performance. Our results show that SignalP 4.0 was the best signal-peptide predictor for all three organism types (Fig. 1). This comes at a price, however, because SignalP 4.0 was not in all cases as good as SignalP 3.0 according to cleavage-site sensitivity or signal-peptide correlation when there are no transmembrane proteins present (Supplementary Results). An ideal method would have the best SignalP 4.0: discriminating signal peptides from transmembrane regions