• R M Beri

      Articles written in Proceedings – Section A

    • Nencki’s reaction with cresols

      R M Beri K L Gakhar P S Rao

      More Details Abstract Fulltext PDF

      The condensation of cresols with acetic, propionic and butyric acids was tried under conditions of Nencki’s reaction employing anhydrous zinc chloride as the condensing agent. Onlyo-cresol gave rise to both theortho- andpara-substituted derivatives, while them- and thep-cresols produced only theortho-substituted products. The yields varied with the duration of heating.

    • Analysis of sugars using paper chromatography (Horizontal migration)

      P S Rao R M Beri

      More Details Abstract Fulltext PDF

      Employing filter-paper chromatography a convenient method (Horizontal Migration Method) has been developed for the identification of reducing sugars, when present either alone or in mixtures. Since only small amounts are required for the identification, the method may be useful both to the regular student and the research worker. Under the conditions of the experiment the components of mixtures separate in 1/2 to 1 1/2 hours into circular zones, which can be easily detected by spraying with a suitable reagent like aniline hydrogen phthalate. Each sugar has its own characteristic circular RF value (the ratio between the distances through which the sugar moves on the one hand and the solvent front on the other) with a particular solvent, and its determination enables the identification of the sugar. Since some of the sugars have the same or very close RF values with a particular solvent, it is desirable to run the chromatogram with at least 2 different solvents to confirm the identification. In the case of mixtures it may be necessary to determine the RF values with 3 or more different solvents in order to definitely identify the individual components. Some of the advantages of the method are the speed and ease of manipulation, simplicity and compactness of the apparatus, and accuracy and reproducibility of the results.

    • Studies on plant mucilages - Part III. Mucilage from the tubers ofCurculigo orchioides

      P S Rao R M Beri

      More Details Abstract Fulltext PDF

      The mucilage from the tubers ofCurculigo orchioides Gaertn. is constituted from mannose, glucose and glucuronic acid in the molecular ratio of 6:9:10. It is present to an extent of 8·12 per cent.

      The results of a proximate analysis of the root powder are also given.

    • Analysis of sugars and uronic acids using paper chromatography (Horizontal Migration)

      P S Rao R M Beri P Ramachandra Rao

      More Details Abstract Fulltext PDF

      Using the horizontal migration method of filter paper chromatography, the separation and identification of glucuronic and galacturonic acids and their barium salts have been effected.

    • Tamarind seed jellose1: Fermentative degradation

      P S Rao R M Beri

      More Details Abstract Fulltext PDF

      Tamarind seed jellose undergoes fermentative degradation in aqueous solution yielding a hexasaccharide which is composed of xylose, galactose and glucose in the molecular proportion of 2:1:3. The carbohydrate, which may be named Tamarindose, decomposes at 228–30°C. and has a specific rotation of + 73·8° at 30°. Its acetate melts with decomposition at 172–74° and has a specific rotation of + 43·6° in methyl alcoholic solution at 30°.

    • Analysis of amino acids using paper chromatography (Horizontal migration)

      P S Rao R M Beri

      More Details Abstract Fulltext PDF

      Using the horizontal migration method of paper chromatography the separation and identification of naturally-occurring amino acids have been effected.

    • Resinol from the nuts ofSemecarpus travancoricus

      S V Puntambekar R M Beri

      More Details Abstract Fulltext PDF

      The resinol on treatment with formaldehyde formed thermoplastic products, shining and varying in shades from reddish brown to jet black. The lacquer forming ingredient has been isolated and identified as laccol (3-heptadecadienyl catechol), confirmed by the preparation of its hydrogenated product and its derivatives.

      The tarry residue, left after vacuum distillation, polymerises on standing to a shining friable mass, soluble in benzene, acetone and chloroform and appears to be a mixture of high molecular phenols.

    • Acetylation of tamarind seed Jellose

      P S Rao R M Beri

      More Details Abstract Fulltext PDF

      The hexa, duodeca and hexadeca acetyl derivatives of tamarind seed jellose have been prepared by treatment with acetic anhydride under different conditions. Boiling glacial acetic acid also effects partial acetylation.

      Some of the acetyl derivatives in appropriate solvents give fairly strong, flexible, glossy and transparent films, which adhere to glass, metallic and also wooden surfaces. They may also be useful as thermoplastic resins on account of their wide melting range.

  •  

© 2021-2022 Indian Academy of Sciences, Bengaluru.