Carbohydrates of the fruit ofRosa canina

Abstract

It is known that rose fruit contains biologically active compounds (vitamins B 2, C, K, and P, carotene, organic adds, flavonoids, and tannin substances), which are responsible for healing properties [1---6], but there is no information on their carbohydrate content. We have investigated the carbohydrate composition of the fi'uit of Rosa canina. A comparative study was made of the carbohydrate compositions of the fruit (FR), of an aqueous extract (AER), and of the pulp remaining after the production of the preparation Kholam~ (PR). As a result we found the compositions of the alcohol-soluble fraction (ASF), of the water-soluble polysaccharides (WSPSs), and of the pectin substances (PSs) (Table 1). The commintlted air--dry raw material (FR and PR) was treated with 82% alcohol (1:2) twice for 1 h each time at the boil, and the combined extracts were concentrated, giving the total ASF (Table 1). By paper chromatography of the ASF of the FR (system 1, butan-l-olmpyridine---water (6:4:3), Ffltrak FN-11 paper) we detected glucose and sucrose. The WSPSs were extracted with water at 20~ twice for 2 h each. The extracts were evaporated under vacuum and were precipitated with isopropyl alcohol (1:2) (see Table 1). The precipitate of WSPSs formed a light cream-colored water-soluble powder giving a negative reaction for starch with iodine. The aqueous extract from the rose was precipitated with alcohol. The supernatant liquid was evaporated, the yield of ASF was determined (9.1%), and this was separated preparatively by PC for the quantitative determination of glucose (63.1% ) and fructose (35.2%). The precipitate obtained was treated with water at 20~ for 2 h, giving the WSPSs (1.69% on the raw material). The insoluble part consisted of the pectin substances (0.47% on the raw material). In the products of complete acid hydrolysis ( 1 N H2SO 4, 36 h) of the FR and AER we detected (PC, system 1) glucose and fructose in mounts of 2.1, 97.8 and 3.7, 96.2%, respectively.