MARC 主機 00000nam  2200337   4500 
001    AAINR31045 
005    20081220111006.5 
008    081220s2007                        eng d 
020    9780494310458 
035    (UMI)AAINR31045 
040    UMI|cUMI 
100 1  Green, Richard C 
245 10 Physicochemical properties and phenolic composition of 
       selected Saskatchewan fruits: Buffaloberry, chokecherry 
       and sea buckthorn 
300    318 p 
500    Source: Dissertation Abstracts International, Volume: 68-
       09, Section: B, page: 5646 
502    Thesis (Ph.D.)--The University of Saskatchewan (Canada), 
520    There is increasing interest in the commericalization of 
       native fruits for utilization as foods and medicinal 
       extracts. This study was undertaken to determine the 
       physicochemical properties and phenolic composition of 
       selected Saskatchewan native fruits, including 
       buffaloberry (Shepherdia argentea  Nutt.), chokecherry 
       (Prunus virginiana L.) and sea buckthorn (Hippophae 
       rhamnoides L.). The physicochemical analyses included 
       carbohydrate content, CIELAB colour values, organic acid 
       composition, phenolic content, % seed, soluble solids, pH,
       total solids, total titratable acidity and proximate 
       composition. Fruit samples were collected and analyzed 
       over four crop years. The proanthocyanidin content was 
       also determined photometrically after acid 
       depolymerization in acid-butanol. Buffaloberry contained a
       proanthocyanidin concentration of 505 +/- 32 mg/100 g 
       fresh fruit and this level was 10 fold higher than that of
       chokecherry and sea buckthorn. Chokecherry was found to 
       contain an anthocyanin concentration of 255 +/- 35 mg/100 
       g fresh fruit, as determined using the pH differential 
520    Two high performance liquid chromatography (HPLC) methods 
       were developed for simultaneous determination of seven 
       phenolic classes, including anthocyanins, hydroxybenzoic 
       acids, hydroxycinnamic acids, flavanols, flavanones, 
       flavones and flavonols in aqueous methanol extracts. Based
       on the semi-quantitative analysis of the total phenolic 
       chromatographic index (TPCI), chokecherry contained the 
       highest levels of phenolic compounds with a concentration 
       of 3,327 +/- 469 mug/g fresh fruit followed by 
       buffaloberry (578 +/- 73 mug/g fresh fruit) and sea 
       buckthorn (477 +/- mug/g fresh fruit) 
520    The antioxidant activity of the fruit extracts was 
       determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 
       2,2'-azinobis-3-ethylbenzthiazoline-sulphonic acid (ABTS) 
       radical scavenging assays. Buffaloberry and chokecherry 
       produced the highest radical scavenging activity and were 
       at least five fold greater than that of sea buckthorn. The
       major radical scavenging compounds in buffaloberry were 
       ascorbic acid and proanthocyanidins. Radical scavenging 
       activity of chokecherry fruit was largely attributable to 
       its anthocyanins, flavonols and hydroxycinnamic acids. 
       Prominent antioxidants in sea buckthorn included ascorbic 
       acid, proanthocyanidins and flavonols 
520    Certain individual compounds in the phenolic extracts were
       identified by HPLC-photodiode array and HPLC-mass 
       spectrometry. Rutin was found in all of the extracts. 
       Other phenolic compounds identified included catechin in 
       sea buckthorn, and chlorogenic acid and quercetin in 
       chokecherry. The chokecherry fruit pigments were comprised
       of two major anthocyanins and these were identified as 
       cyanidin 3-glucoside and cyanidin 3-rutinoside. A 
       preparative scale purification method for these 
       anthocyanins using centrifugal partition chromatography 
       (CPC) was determined. Under the CPC conditions employed, 
       cyanidin 3-glucoside and cyanidin 3-rutinoside were 
       purified to concentrations of 84 and 90%, respectively 
590    School code: 0780 
590    DDC 
650  4 Agriculture, Food Science and Technology 
650  4 Chemistry, Agricultural 
690    0359 
690    0749 
710 20 The University of Saskatchewan (Canada) 
773 0  |tDissertation Abstracts International|g68-09B 
856 40 |u