Acid In Plant Extracts Research Articles

Qualitative and quantitative analysis of common and uncommon amino acids in plant extracts

A method is described for the automatic qualitative and quantitative analysis of free amino acids, common and uncommon, present in plant extracts. An automatic amino acid analyser has been modified to allow the absorption of ninhydrin colours to be measured at various wavelengths and at different stages of colour development, permitting the identification of amino acids by ninhydrin colour as well as by elution time. Data are processed using a programmable calculator, and the complete spectrum of the amino acids from each plant species is stored in a coded form on magnetic tape. Comparisons of different spectra can be made rapidly either by simultaneous visual display on an oscilloscope or by direct computer correlation.

High-performance liquid chromatographic analysis of abscisic acid in plant extracts

A HPLC assay for ABA and bound ABA is described. The method uses conventional acid-base ether extractions for partial cleanup of the plant extracts followed by Sephadex G-25 column fractionation. The ABA is separated and detected by HPLC on a 3 m × 2.1 mm i.d. column of SCX-Zipax with a uv detector. The method is sensitive to less than 10 ng of ABA. HPLC analyses of ABA have been performed on extracts of leaves, stems, and roots of soybeans, pinto beans, cotton, apple seedlings, and the albedo and flavedo sections of orange peels.

Kinetic study of possible intermediates in the biosynthesis of chlorogenic acid in Cestrum poeppigii

p-Coumaric and 3- O-p-coumarylquinic acid seem to be important precursors of chlorogenic acid in the leaves of Cestrum poeppigii. 3- O-Cinnamylquinic acid, which has a very small metabolic activity, is of little importance in this respect. The kinetics of incorporation of radioactivity from t-cinnamic acid-3-[ 14C] into p-coumaric, 3- O-p-coumarylquinic, chlorogenic and 3- O-cinnamylquinic acid showed that the biosynthetic rates for these products decrease in the order shown. For p-coumaric acid, which has a markedly high metabolic activity, a turnover rate of 28 μg/hr and per gram fresh plant leaf, was calculated. Some trapping experiments with caffeic acid, and the acids mentioned above and using either t-cinnamic acid-3-[ 14C] or p-coumaric acid-2-[ 14C] as precursor, are discussed. A HPLC method for the rapid determination of phenolic acids in plant extracts, is described.

Détermination quantitative des acides organiques dans les extraits végétaux : Amélioration de la technique d'analyse par chromatographie de partage sur colonne de gel de silice

Quantitative determination of organic acids in plant extracts. Improvement in the analysis by partition chromatography on a silica gel column The organic acids extracted from plant tissue are separated in two groups by passage over an anionic resin column, Amberlite IRA-400. The first group, eluted by means of a 0.9% aqueous solution of ammonium carbonate, includes the monocarboxylic acids pyrrolidonecarboxylic, glycolic, and glyceric; the second, eluted by means of a 6% aqueous solution of ammonium carbonate, comprises the dicarboxylic acids mesaconic, fumaric, succinic, malonic, oxalic, malic, and tartaric and the tricarboxylic acids cis- and trans-aconitic, citric and isocitric. The organic acids of each group are then automatically separated by partition chromatography on a silica gel column using as eluant for the first group a solvent containing chloroform and for the second a solvent containing chloroform and cyclohexane. The organic acids once eluted are determined by spectrophotometry in the presence of o-nitrophenol sodium salt.

The identification and quantitative analysis of abscisic acid in plant extracts by gas-liquid chromatography

New techniques are described which permit the quantitative analysis of microgram quantities of abscisic acid in plant extracts by gas chromatography. Presumptive methyl abscisate peaks on gas chromatograms are positively identified by photosensitised isomerisation to methyl 2-trans-abscisate. Losses of abscisic acid during pre-purification are corrected by using 2-trans-abscisic acid as an internal standard.

A column and paper chromatographic method for separation of N-dimethylamino-succinamic acid in plant extracts

A column and paper chromatographic method for separation of N-dimethylamino-succinamic acid in plant extracts

Analysis of iron chelates in plant extracts. II.—ferric ethylenediaminebis‐(o‐hydroxyphenylacetic acid)

AbstractThe behaviour of ethylenediaminebis‐(o‐hydroxyphenylacetic acid) (EDHPA, Chel 138) and its ferric iron chelate (Fe‐EDHPA) with activated charcoal and a cation‐exchange resin is described and procedures are proposed for the recovery of this chelating agent from plant extracts. Fe‐EDHPA in aqueous solution is adsorbed by activated charcoal and eluted by ethanolic ammonia. EDHPA in neutral or acid solution is adsorbed on the H+ form of the cation‐exchange resin Zeocarb‐225 and is completely eluted by ethanolic ammonia. Fe‐EDHPA is held on this resin by working with solutions initially at pH I. The Fe‐EDHPA can be identified by paper chromatography.In addition, a modification is given for the previously‐proposed procedure for the detection of ethylenediaminetetra‐acetic acid in plant extracts.

Indirect method for determination of phytic acid in plant extracts containing reducing substances

Indirect method for determination of phytic acid in plant extracts containing reducing substances

The detection of aromatic acids in plant extracts by the ultraviolet absorption spectra of their ions

Summary In alcoholic solution the wavelength of maximum absorption of those acids which contain a carboxyl group attached to, or conjugated with, an aromatic nucleus is shifted toward the shorter wavelengths in the presence of sodium acetate. This shift provides an easy method for distinguishing aromatic acids from their esters and other phenolic compounds in plant extracts. Esters and simple phenols do not show such a shift. Addition of sodium ethylate to an alcoholic solution of an acid or ester results in a bathochromic shift. The shift is considerably greater with esters than with the corresponding acids.

Chromatographic and Spectroscopic Properties of Ellagic Acid, and its Occurrence in Dicotyledonous Plants

CHROMATOGRAPHIC and spectrophotometric properties of ellagic acid have now been investigated in order to facilitate the identification of this acid in plant extracts and hydrolysates. In early studies, ellagic acid has not always been adequately characterized; but the present work has confirmed the occurrence of this substance in a wide range of dicotyledonous plants1. Ellagic acid has also been identified in Terminalia arjuna, bellirica, citrina, pallida and travencoriensis for the first time.

The reduction of dehydroascorbic acid in plant extracts

The reduction of dehydroascorbic acid in plant extracts