Sempervirenic acid,a diterpene acid from Solidago sempervirens

Sempervirenic acid, a new diterpene has been isolated from Solidago sempervirens and its structure determined by spectroscopic methods and chemical conversions to be 3β-acetoxy-labda-7,13-diene-15-oic acid.     

Preparation and purification of pteroic acid from folic acid

Crude pteroic acid, obtained by microbiological degradation of folic acid, has been purified by column chromatography on cellulose CF11, eluting with 0.1 M glycine buffer of pH 10.0, containing 0.15% w/v ascorbic acid and saturated with isoamyl alcohol.     

Formation of 6,13-dihydroxyoctadecatrienoic acid isomers from gamma-linolenic acid

Incubation of gamma-linolenic acid with soybean lipoxygenase initially at pH 9.3 and subsequently at pH 7.9 gave rise to the conjugated triene dioxygenation product (lambda max = 267 nm, greater than 50% yield), which was reduced to form 9-cis isomer of 6,13-dihydroxyoctadecatrienoic acid (6,13-diHOT) accompanied by minor isomers. Meanwhile, hemoglobin converted 13-hydroperoxyoctadecatrienoic acid into two major 9-trans isomers of 6,13-diHOT and two 9-cis isomers as minor products. The four isomers of 6,13-diHOT methyl ester were separated from each other on SP-HPLC, and characterized by chromatographic, spectrometric and cis----trans isomerization analyses.     

Ribonucleic acid from coffee beans

A method of extraction of RNA from coffee based on phenol treatment is described. Effectsf of various agents and pH of the extracting buffer on the efficiency of extraction were studied. The best extracting solution is 0·2 M Tris-HCl buffer at pH 7·4 with 1% sodium dodecyl sulphate and 0·05% EDTA. RNA (5–6%) is lost in the tissue residue and 4·6% in the interphase layer. No significant deviation of the spectral characteristics of the RNA solutions obtained from three samples of coffee from that for purified yeast RNA is observed. The purine-pyrimidine ratio for the RNA has been found to be in the range of 1·25–1·38.     

Heteropolysaccharides from lactic acid bacteria

Microbial exopolysaccharides are biothickeners that can be added to a wide variety of food products, where they serve as viscosifying, stabilizing, emulsifying or gelling agents. Numerous exopolysaccharides with different composition, size and structure are synthesized by lactic acid bacteria. The heteropolysaccharides from both mesophilic and thermophilic lactic acid bacteria have received renewed interest recently. Structural analysis combined with rheological studies revealed that there is considerable variation among the different exopolysaccharides; some of them exhibit remarkable thickening and shear-thinning properties and display high intrinsic viscosities. Hence, several slime-producing lactic acid bacterium strains and their biopolymers have interesting functional and technological properties, which may be exploited towards different products, in particular, natural fermented milks. However, information on the biosynthesis, molecular organization and fermentation conditions is rather scarce, and the kinetics of exopolysaccharide formation are poorly described. Moreover, the production of exopolysaccharides is low and often unstable, and their downstream processing is difficult. This review particularly deals with microbiological, biochemical and technological aspects of heteropolysaccharides from, and their production by, lactic acid bacteria. The chemical composition and structure, the biosynthesis, genetics and molecular organization, the nutritional and physiological aspects, the process technology, and both food additive and in situ applications (in particular in yogurt) of heterotype exopolysaccharides from lactic acid bacteria are described. Where appropriate, suggestions are made for strain improvement, enhanced productivities and advanced modification and production processes (involving enzyme and/or fermentation technology) that may contribute to the economic soundness of applications with this promising group of biomolecules.     

Epi-Ililic acid from Alcantara Ekmaniana

The aerial parts of Alcantara ekmaniana afforded, in addition to known compounds, epi-ilicic acid. The furanogermacranolides isolated indicate a close relationship between this genus and other members of the same tribe.     

Dihydrodendroidinic acid from Pleurocoronis pluriseta

The diterpenic acid, dihydrodendroidinic acid, was characterized from the aerial parts of Pleurocoronis pluriseta.