Fermentation properties of oligosaccharides derived from orange peel pectin were assessed in mixed fecal bacterial culture. The orange peel oligosaccharide fraction contained glucose in addition to rhamnogalacturonan and xylogalacturonan pectic oligosaccharides. Twenty-four-hour, temperature- and pH-controlled, stirred anaerobic fecal batch cultures were used to determine the effects that oligo...

The primary cell-wall matrix of most higher plants is composed of large amounts of uronic acids, primarily D-galacturonic acid residues in the backbone of pectic polysaccharides. Uridine diphosphate (UDP)-glucose dehydrogenase is a key enzyme in the biosynthesis of uronic acids. We produced transgenic alfalfa (Medicago sativa) plants expressing a soybean UDP-glucose dehydrogenase cDNA under the...

Direct aqueous photolysis of cis-pinonic acid (PA; 2-(3-acetyl-2,2-dimethylcyclobutyl)acetic acid; CAS Registry No. 473-72-3) by 280-400 nm radiation was investigated. The photolysis resulted in Norrish type II isomerization of PA leading to 3-isopropenyl-6-oxoheptanoic acid (CAS Registry No. 4436-82-2), also known as limononic acid, as the major product, confirmed by (1)H and (13)C NMR analysi...

The polysaccharides of cell walls isolated from the fleshy, edible part of the fruit of the monocotyledon pineapple [Ananas comosus (L.) Merr.] (family Bromeliaceae) were analyzed chemically. These cell walls were derived mostly from parenchyma cells and were shown histochemically to be unlignified, but they contained ester-linked ferulic acid. The analyses indicated that the noncellulosic poly...

Previous methods of extracting pectin from sugar-beet have used pulp as the starting material. As the temperature and pressure of the pulping process may modify the architecture of the cell wall, we have adapted a relatively non-disruptive method to characterise cell wall material (CWM) isolated directly from the sugar-beet. Cell walls from mature sugar-beets (Beta vulgaris L Aztec) were sequen...

Nearly all polysaccharides in plant cell walls are O-acetylated, including the various pectic polysaccharides and the hemicelluloses xylan, mannan, and xyloglucan. However, the enzymes involved in the polysaccharide acetylation have not been identified. While the role of polysaccharide acetylation in vivo is unclear, it is known to reduce biofuel yield from lignocellulosic biomass by the inhibi...

Cell walls were isolated from the mesocarp of grape (Vitis vinifera L.) berries at developmental stages from before veraison through to the final ripe berry. Fluorescence and light microscopy of intact berries revealed no measurable change in cell wall thickness as the mesocarp cells expanded in the ripening fruit. Isolated walls were analyzed for their protein contents and amino acid compositi...

In this study, the influence of primer contamination on enamel bonding was analyzed. Adper Scotchbond Multi-Purpose (SMP), CLEARFIL SE Bond 2 (SE2), Universal (SBU) Adhesive, and Etchant (35% phosphoric acid; PA) were used. Ground bovine enamels divided into eight groups based protocols. The interfaces after an acid-base challenge observed via scanning electron microscopy to determine resistant...

Rhamnogalacturonan I (RGI) is a pectic polysaccharide composed of a backbone of alternating rhamnose and galacturonic acid residues with side chains containing galactose and/or arabinose residues. The structure of these side chains and the degree of substitution of rhamnose residues are extremely variable and depend on species, organs, cell types and developmental stages. Deciphering RGI functi...