differ with plant species. One characteristic of anther development is the accumulation of nutrients, generally polysaccharides or neutral lipids, in the pollen pool to fuel the subsequent pollen ontogeny, germination on the stigma surface, and growth of
than 190 compounds have been isolated from D. officinale ( Tang et al., 2017 ), of which polysaccharide is one of the major active constituents, exhibiting immunomodulatory and cardioprotective activities ( Dou et al ., 2016 ; He et al., 2016
industries ( Gu, 2019 ; Zhang, 2020 ). The root tubers of P. heterophylla contain pharmacological ingredients such as saponins, polysaccharides, amino acids, and cyclopeptides ( Ma et al., 2017a ). Modern medical research shows that the polysaccharides in
histochemical changes associated with the various developmental stages of anthers were investigated, with a focus on changes of polysaccharides and lipids, which are nutritional materials. Study on the synthesis and distribution of nutritional constituents in
Abstract
Three tomato (Lycopersicon esculentum Mill.) lines with divergent viscosities and their F1, BCP1, BCP2, and F2 progeny were analyzed for serum viscosity, gross viscosity, and five alcohol insoluble solids (AIS) components. The components were water soluble polysaccharides and polygalacturonides, water-insoluble polysaccharides and polygalacturonides, and acid-hydrolyzed polysaccharides. Stepwise regression analysis of data from parents and progeny was used to establish the relationships between a change in composition and a change in viscosity. The polygalacturonides accounted for most of the variation in gross viscosity among the parental lines. The data indicate that water-insoluble, pectinol-solubilized polysaccharides have the potential for making a large contribution to viscosity at higher concn. The water-soluble polysaccharides and complex polysaccharides (solublized in H2SO4) contributed little to gross viscosity. The sugars identified in the AIS were arabinose, ribose, xylose, mannose, galactose, and glucose. Galacturonic acid was the only organic acid detected. Concentration of the compounds varied among the fractions and among the parental lines.
Abstract
The ultrastructural localization of polysaccarides in Malus domestica Borkh. leaf cuticles was investigated by electron microscopy staining. The cuticle/cell wall interface was not stained by ruthenium red or hydroxylamine-ferric chloride, indicating the lack of a distinct pectin layer. The inner region of the cuticle was intensely and uniformly stained by phosphotungstic acid (PTA) and was lightly stained by silver proteinate, indicating the presence of polysaccharides, which in part may be pectin as indicated by staining with ruthenium red. Fibrils in the inner region of the cuticle were not stained by ruthenium red, hydroxylamine-ferric chloride or silver proteinate, but appeared lightly stained by PTA; this suggests by deduction that the fibrils may consist of cutinized cellulose. The outer region of the cuticle was not stained by any of the staining procedures, indicating the lack of polysaccharides.
Softening and liquefaction of `Solar Set' locules was studied by examining cell wall polysaccharides during fruit developmental stages (FDS) of immature green, mature green and breaker. Ethanol insoluble solids (EIS) were sequentially extracted by H2O, CDTA, and Na2CO3 solutions. The chromatograms of gel filtration among the same-solution extracts of EISs from three FDS were similar. Gradient DEAE also yielded similar patterns among FDS in each extraction solvent, even though the patterns of Na2CO3 extracts differed from those of H2O and CDTA extracts. The mole ratio of total polyuronides decreased for Gal, Ara, and Xyl at later FDS in both EIS and in all extracted polymers. Gal had the highest mole percentage of total neutral sugars, followed by Ara, Xyl, and Rha. While the mole percentage of neutral sugars for Gal, Rha, Ara, and Xyl were relatively similar among FDS in H2O extracts, those in CDTA and Na2CO3 extracts either increased or decreased, depending on individual neutral sugar. SDS-PAGE showed increased density in locule-tissue proteins, especially one with a molecular weight of less than 20 kDa, during later FDS. Results indicate that pectin depolymerization was limited and major neutral sugars commonly composing side chains showed a net decrease.
A rapid and simple procedure is described for efficiently extracting intact RNA from mango (Mangifera indica L. cv. Manila) mesocarp, a tissue rich in polysaccharides. The RNA can be used for in vitro translation, northern blots, and cDNA synthesis. This method is applicable to other fleshy fruits rich in polysaccharides.
Abstract
Suspension-cultured pear (Pyrus communis ‘Bartlett’) cells cold-acclimated during exposure to 2°C. Cold acclimation was accompanied by changes in soluble extracellular polysaccharides and in the deposition of callose in the cell wall. Release of a relatively small neutral polysaccharide into culture medium was increased at 2°. However, low temperature decreased the extracellular accumulation of a larger molecular weight (M r) pectic polysaccharide. The reduced amount of pectic polysaccharide may have been the result of both a low-temperature-enhanced degradation of existing polysaccharide and an inhibition of new synthesis or secretion. The effect of low temperature on callose deposition was observed using an aniline blue fluorescent staining procedure. Pear cells held at 2° showed far more intense staining than those at 22°, indicating increased deposition of callose or other β-1,3-glucans at the cell surface during cold acclimation.
Various species and cultivars of citrus were studied to determine the relationship between texture and cell wall polysaccharide content of fruit flesh. Among those tested cultivars, navel orange (Citrus sinensis Osbeck) and hassaku (C. hassaku Hort. ex Tanaka) were firmest, `Fukuhara orange' (C. sinensis Osbeck) was intermediate, and satsuma mandarin (C. unshiu Marc.) was softest. There was a 3-fold difference in firmness among the 12 citrus cultigens measured. Cohesiveness values ranged from 0.30 to 0.49 and were not correlated with fruit firmness. Sugar content in each cell wall fraction was highest in the water and EDTA fractions, followed by the hemicellulose fraction, and was lowest in the cellulose fraction. Correlation coefficients between firmness and sugar content ranged from 0.69 to 0.88 and were highest in the cellulose fraction. This study suggests that firmness of fruit flesh among the cultigens is influenced by cell wall polysaccharide composition. Chemical name used: ethylenediaminetetraacetic acid (EDTA).