Branfoot (1) has summarised the early work on pectic substances. Bonner (2), Norman (3), and Hirst and Jones (4) have reviewed later work on the structure of these substances. Pectic materials that approximate the composition and have some of the properties of pectic acid are widely distributed but in small amounts in mature hardwoods. In 1925 O’Dwyer (5) isolated such a material from beechwood...

Pectin methylesterase was extracted from potato tubers and partially purified in a single chromatographic step at large industrial scale. The preparation obtained in this way matched the temperature and pH profile of the species reported earlier by Puri et al. (Food Chemistry 8:203-213, 1982) and was enriched 23 times relative to the original potato tubers on a dry matter basis. Potato PME indu...

The ability of the hyperthermophilic bacterium Thermotoga maritima to grow on pectin as a sole carbon source coincides with the secretion of a pectate lyase A (PelA) in the extracellular medium. The pel A gene of T. maritima was functionally expressed in Escherichia coli as the first heterologously produced thermophilic pectinase, and purified to homogeneity. Gel filtration indicated that the n...

Sodium montmorillonite (Na-MMT) clay was modified with three different unnatural amino acids in order to design intercalated clay structures that may be used for bone biomaterials applications. Prior work on polymer-clay nanocomposites (PCNs) has indicated the effect of the appropriate choice of modifiers on enhancing properties of PCNs. Our X-ray diffraction results indicate an increase in the...

A polygalacturonase (PGase) was purified from Trichoderma harzianum , grown on citrus peel, by anion exchange and size exclusion chromatographies. The enzyme had molecular mass of 29 kDa. The extent of hydrolysis by PGase was decreased with increasing of pectin esterification degree. m m ax K and V , using polygalacturonic acid as substrate, were 1.42 mg and 0.66 ìmol reducing sugar, respective...

The rough lemon (Citrus jambhiri) gene encoding polygalacturonase-inhibiting protein (RlemPGIPA) was overexpressed in the pathogenic fungus Alternaria citri. The overexpression mutant AcOPI6 retained the ability to utilize pectin as a sole carbon source, and the overexpression of polygalacturonase-inhibiting protein did not have any effect on the growth of AcOPI6 in potato dextrose and pectin m...

Polygalacturonase is a valuable biocatalyst for several industrial applications. Production of polygalacturonase using the Aureobasidium pullulans stain isolated from Saharan soil of Algeria was investigated. Its capacity to produce polygalacturonase was assessed under submerged culture using tomato pomace as an abundant agro-industrial substrate. Optimization of the medium components, which en...

Fusarium oxysporum f. sp. vasinfectum penetration hyphae infect living cells in the meristematic zone of cotton (Gossypium barbadense L.) roots. We characterized wall modifications induced by the fungus during infection of the protodermis using antibodies against callose, arabinogalactan-proteins, xyloglucan, pectin, polygalacturonic acid and rhamnogalacturonan I in high-pressure frozen, freeze...

Mucor circinelloides produced an extracellular polygalacturonase enzyme, the production of which was enhanced when various production parameters were optimized. Maximum polygalacturonase (PGase) activity was obtained in 48 h at 30°C and pH 4.0 with pectin methyl ester (1% w/v) as carbon source and a combination of casein hydrolysate (0.1% w/v) and yeast extract (0.1% w/v) as nitrogen source. Th...