Plant tissue isolation

Gregorich, E. G., Monreal, C. M., Schnitzer, M., and Schulten, H.-R. (1996). Transformation of plant residues into soil organic matter chemical characterization of plant tissue, isolated soil fractions, and whole soils. Soil Sci. 161(10), 680-693. 

There are color reactions for general classes of carbohydrates (Dische, 1962), e.g., those in Table I summarize a few general-purpose tests for routine differential staining of plant-tissue isolates. 

C12H20O4. M.p. 165°C. A plant growth hormone, which is produced in damaged plant tissue, and on diffusing into adjacent intact tissue cells stimulates them to divide. Traumatic acid has been isolated from the pods of green beans. 

In addition to the isolation of steroid raw materials from whole plants, plant tissue cultures have been iavestigated as an alternative source of these steroids. Despite many advances (128), there are no iadustrial appHcatioas of plant cell cultures for the production of steroids (129,130). 

Tissue and Bacteria Electrodes The limited stability of isolated enzymes, and the fact that some enzymes are expensive or even unavailable in the pure state, has prompted the use of cellular materials (plant tissues, bacterial cells, etc.) as a source for enzymatic activity (35). For example, banana tissue (which is rich with polyphenol oxidase) can be incorporated by mixing within the carbon paste... 

Within the scope of this review, the contributions of the last decade concerning cell-wall polysaccharides isolated from woody and other plant tissues will be reviewed according to the above-proposed classification of hemicelluloses including larch arabinogalactans. The present review article updates and extends previous reviews [3-5] and will focus in particular on new investigated plant sources, isolation methods, structural features, physicochemical and various functional properties of hemicelluloses. Attention will also be paid to the modification of isolated hemicelluloses or hemicellulosic materials and the appHcation possibiUties of hemicelluloses and their derivatives, including their use for the production of composite materials and other biomaterials. 

In some cases pectinolytic enzymes have been associated with virulence and it is generally accepted that pectinolysis by these bacteria facilitates their entry and spread in plant tissue. In Rhizohium, these enzymes may play a role in the root infection process that precedes nodule formation (Hubbell et al 1978). A. irakense has never been reported to be pathogenic on plants. It can therefore be speculated that moderate and strictly regulated pectinolysis of A. irakense facilitates entry in the outer cortex of plants roots, since A. irakense has been isolated from surface-sterilized roots. It is likely that breakdown of plant polysaccharides by root colonizing bacteria can provide them with extra carbon source. 

Although both catechins and proanthocyanidins are currently found in plant tissue composition, as reported above, their isolation requires sometime time-consuming procedures and purity and reproducibility are often suspect. 

Classical approaches to plant DNA isolation aim to produce large quantities of highly purified DNA. However, smaller quantities of crudely extracted plant DNA are often acceptable for PCR analysis. Another efficient method for preparation of plant DNA for PCR is a single-step protocol that involves heating a small amount of plant tissue in a simple solution. Several factors influence nucleic acid release from tissue salt, EDTA, pH, incubation time and temperature. These factors must be optimized for different sample substrates. EDTA in the sample solution binds the Mg + cofactor required by the Taq polymerase in the PCR, so the EDTA concentration in the solution, or the Mg + concentration in the PCR, must be carefully optimized. 

Effects of Allelochemlcals on ATP Supply. Allelochemlcals might decrease the ATP content of tissue by either increasing ATP utilization or decreasing ATP production. Some allelochemlcals that inhibit mineral absorption decrease ATP content of plant tissues. Salicylic acid decreased the ATP content of oat roots in a pH dependent manner (Figure 3). This result suggested that mitochondrial production of ATP was decreased in the tissue. On the other hand, Tillberg (38) found that salicylic acid and cinnamic acid increased the ATP content of Scenedesmus. Various flavonoids inhibited ATP production by mitochondria Isolated from cucumber (Cucumls satlvus L.) hypocotyls (54). Flavones such as kaempferol were more inhibitory than the corresponding flavanones. Substituted cinnamic acids such as caffeic acid were not inhibitory. 

Considerable success has been achieved in isolating plant tissue culture enzymes responsible for specific steps in the biosynthesis of a range of indole alkaloids (187-191). While the subject of biosynthesis is beyond the scope of this review, the value of such enzymes in catalyzing biotransformation reactions... 

The ubiquity of lignin in plant tissue presents an obstacle to the removal and purification of xylan. Lignin retards or prevents the complete solution of xylan either because of mechanical obstruction or perhaps by reason of attachment through as yet unidentified covalent bonds. Furthermore, lignin is partially soluble in the various aqueous alkaline solutions used for dissolving xylan and, consequently, poses a purification problem in various subsequent steps designed to isolate the pure polysaccharide. 

Plant defensins are cystine-rich, cationic peptides ranging in size from 45 to 54 amino acids, of which eight are cysteine. They were first discovered in wheat and barley ° and were proposed to form a novel subclass of thionins, the 7-thionins. As it became clear that they closely resemble mammalian and insect defensins in primary and secondary structure, the term plant defensins was introduced to describe these peptides. It is generally assumed that all plants express plant defensins " and that they are expressed in a wide range of plant tissue, that is, leaves, floral tissue,tubers,bark, root, pods, and seeds,with seeds in particular being from where most plant defensins have been isolated. ... 

Cyclotides have been isolated from many plant tissues, including leaves, stems, flowers, roots, and Recently, the levels of the Mobius-type cyclotide kalata B1 were quantified in various plant tissues of the Rubiaceae family plant Oldenlandia affinis by Seydel and Dornenburg. They found raised levels of kalata B1 in shoot tips and leaves, while flowers and stems contained significantly lower levels of the peptide. 

ACC 71 synthase, i. e. (S)-adenosylmethionine methylthioadenosine lyase (EC 4.4.1.14), has been purified from several plant tissues [116]. Recently, ACC synthase cDNA clones have been isolated and sequenced from wounded fruit tissues of tomato, winter squash, zucchini, ripening apple and tomato fruit. Using the polymerase chain reaction (PCR), four different ACC synthase gene fragments were obtained by amplification of cDNA derived from mRNA of tomato... 

A few novel N-containing and alkaloid products have been isolated from dicot plant endophytes recently. Although not nearly as numerous as the hydrocarbon products, the implications of some of these compounds are significant. Simplest among the amino and amide compounds are 3-nitropropionic acid (NPA)(167) and indole-3-acetic acid (IAA)(168). NPA is isolated frequently from plant tissues and it has significant biological activity. Chomcheon et isolated... 

UDPG-GTases that use phenolic acids as acceptor molecules have been Isolated from several plant tissues. These include leaves of sweet clover (28), geranium (29), Oestrum euenthes (30), oak (31,... 

Since ellagic acid is probably not encountered free in large amounts in fresh plant tissues, but rather as one or more bound forms, we isolated and bioassayed geraniin. On a mmol/kg diet basis, geraniin was almost twice as active as a growth inhibitor of... 

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