Extraction and Isolation of ß-Glucan from Grain Sources-A Review.

A collective report on the extraction and isolation of ß-glucan from grain sources, namely, oat, barley, and wheat is presented. An analysis on the effect of medium, pH, and temperature on the purity and yield of the ß-glucan derived under acidic/alkaline/aqueous/enzymatic conditions is also made. Water extraction and alkali extraction processes are preferred as the yield and recovery of extracted ß-glucan were good. Cost-effective development of the process for deriving high molecular weight ß-glucan is the current requirement for its wide applications in food and pharmaceutical industries.

Chromatographic separation studies of penicillins, cephalosporins and carbapenems on transition-metal silicate modified silica layers.

The chromatographic behavior of penicillins, cephalosporins and carbapenems has been studied on the thin layers of transition-metal ion (viz. Ni(2+)/Zn(2+)/Cu(2+)/Co(2+)) silicate modified silica. Transition-metal silicate (3.92%) and silica (96.08%) were found to be optimum and resulted in spherical-compact spots and improved resolution of the analytes. The effect of various mobile phases was also investigated. The chromatograms were visualized as yellow spots by placing in an I(2)-chamber. The method has been found to be reproducible and convenient for routine analysis.

Chromatographic studies of some cephalosporins on thin layers of silica gel G-zinc ferrocyanide.

A simple, selective and precise thin-layer chromatographic method has been developed for the analysis of eight cephalosporin antibiotics, namely cephadroxil, cephalexin, cefixime, cefaclor, cefpodoxime proxetil, cefuroxime axetil, cefotaxime sodium and ceftriaxone sodium. The hR(F) values of these cephalosporins were investigated on silica gel G-zinc ferrocyanide layers. Mixing of zinc ferrocyanide with silica gel G resulted in a decrease in hR(F) values, removal of tailing and better resolutions. The influence of silica gel G-zinc ferrocyanide ratio and mobile phases on the chromatographic behavior of cephalosporins on thin layers was investigated. Cephalosporins were selectively separated in their binary and ternary synthetic mixtures and pharmaceutical formulations. Quantitative separations of cephalosporins from their synthetic mixtures were also achieved with good recoveries (97.8-100.3%).

Spectrophotometric determination of penicillins in pure and pharmaceutical formulations using Folin-Ciocalteu reagent.

A new combination of time, temperature, and alkali is described for the spectrophotometric determination of amoxicillin and ampicillin using Folin-Ciocalteu reagent. The method is based on the development of blue-coloured product due to the reduction of tungstate and/or molybdate in Folin-Ciocalteu reagent by amoxicillin and ampicillin in alkaline medium. The chromogenic reaction has λ(max) at 720 and 740 nm with molar absorptivity 1.6295 × 104 and 0.1085 × 104 l mol⁻¹ cm⁻¹ in the Beer's Law range 2-10 µg mL⁻¹ and 10-70 µg mL⁻¹ for amoxicillin and ampicillin, respectively. The method is reproducible, quick, inexpensive, and particularly helpful in determining the drug content in commercial dosage forms.