Strawberry (Fragaria x ananassa) is an important worldwide fruit and popular to the consumers due to its nutritional and flavor quality. The content of phenolic compounds in strawberry fruits is affected by various factors such as cultivar, agricultural practice, environment, and ripening stage.
First experiment''s objective is compare with content of biological active compound of ‘Seolhyang’, ‘Maehyang’ which are the most widely cultivated in Korea, and ‘Aram’, ‘Hongsil’ which are development in Gyongnam Agricultural Research cultivars affected by ripening stages (green, turning, half-red, total-red, over-ripening) extracted with 95% pretanol, 50% pretanol and water.
Content of cinchonine affected ripening stage at all cultivalrs. Especially, ''Maehyang'' is the highest content among the four varieties with 809±17 ug/g dry weight, followed by ''Seolhyang'' 727±76 ug/g dry weight, ''Aram'' 598±47 ug/g dry weight and ''Hongsil'' 493±77 ug/g dry weight at 100% ripening at optimal harvesting stage. Content of callistephin related anthocyanins compound didn''t detected at green, turning state. But the riper the fruit, the higher the callistephin content. Especially, 100% ripening at optimal harvesting stage, ''Seolhyang'' is the highest content among the four varieties with 779±25 ug/g dry weight. Followed by ''Hongsil'' 496±16 ug/g dry weight, ''Maehyang'' 469±12 ug/g dry weight and ''Aram'' 338±9 ug/g dry weight. Content of ellagic acid which the main biological compound of the strawberry fruit decrease affected ripening stage at all cultivalrs. Especially, 100% ripening at optimal harvesting stage, ''Hongsil'' is the highest content among the four varieties with 63±5 ug/g dry weight. Follwed by ''Maehyang'' 59±2 ug/g dry weight, ''Aram'' 51±8 ug/g dry weight and ''Seolhyang'' 39±8 ug/g dry weight. Content of isoquercetin increase affected ripening stage at all cultivalrs. Especially, 100% ripening at optimal harvesting stage, ''Aram'' is the highest content among the four varieties with 333±14 ug/g dry weight. Follwed by ''Maehyang'' 257±3 ug/g dry weight, ''Hongsil'' 167±2 ug/g dry weight and ''Seolhyang'' 137±2 ug/g dry weight. Content of quercetin also increase affected ripening stage similar with isoquercetin. Especially, 100% ripening at optimal harvesting stage, ''Hongsil'', ''Seolhyang'', ''Maehyang'' are similar content about 20 ug/g dry weight and ''Aram'' is 14±0 ug/g dry weight. Content of fisetin related flavonoid compound decreases until half-red stage at all cultivalrs. And after total-red stage content of fisetin increase. Especially, ''Hongsil'' is the highest content among the four varieties with 76±7 ug/g dry weight. Followed by ''Seolhyang'' 49±4 ug/g dry weight, ''Aram'' 28±0 ug/g dry weight and ''Maehyang'' 9±1 ug/g dry weight.
Most biological active compounds extracted with 95% pretanol tend to increase follow the ripeing stages. And some of the compounds (cinchonine, (+)-catechin, ellagic acid, cinnamic acid) extracted with 50% pretanol are high value at green stage and then diminish from turning stage, but total-red increase again. Most biological compounds extracted with water similar with 50% pretanol extraction. But especially, content of cinnamic acid sharply increase from total-red stage. Percent inhibition of NO production show activity only 95% pretanol extraction.
Second experiment''s objective is to screen and compare phytochemicals and genetic diversity in six cultivar and 28 breeding lines different strawberry genotypes, by measuring their phenolic, anthocyanins, flavoloids, and tannins content and their inhibition of NO production. In order to foster high-functional strawberry varieties, establish simultaneous analysis condition known as the major component of the strawberry same as first experiment. ''Seolhyang'', ''Maehyang'', ''Ssanta'', ''Arma'',
''Hongsil'' and ''Okmae'' which are six strawberry fruits accessions domestically cultivated and 28 accessions selected by Gyongnam Agricultural Research and Extension Services were evaluated.
Content of callistephin, cinchonine, ellagic acid, fisetin and quercetin have mostly cultivars and breeding lines, but content of (+)-catechin, epi-gallocatechin, isoquercetin, cinnamic acid and kaempferol didn''t appear at all at some cultivar and breeding lines. Content of cinchonine is more high amount at SB-8, SB-9, SB-10 and SB-11 than domestically cultivars. Content of ellagic acid which the main biological compound of the strawberry fruit more high amount at SB-18 breeding line than cultivars. Content of isoquercetin in SB-8, quercetin in SB-14 and SB-19 is more than cultivars. We can know content of biological compounds differs cultivars, ripening stages and extracting solvents. On the basis of these results that breeding lines used for developing the new cultivars. This information should make it possible to select strawberries with an optimal content of bioactive compounds.