The fresh leaves and oven dried leaves from three varieties of black currant (Brodtrop,liangye,Risager)were analysed for the total contents of flavonoids by spectrophotometric methods in terms of rutin equivalent.In ...The fresh leaves and oven dried leaves from three varieties of black currant (Brodtrop,liangye,Risager)were analysed for the total contents of flavonoids by spectrophotometric methods in terms of rutin equivalent.In addition,antioxidant activities of different addition amounts of extracts of black currant (Brodtrop)leaves in lard were measured by the Oven-Storage Test,and compared with the synthetic antioxidants.The results showed the contents of the flavonoids were very rich in the leaves of three varieties from black currant.Among them the leaves of Brodtrop had the highest contents of flavonoids followed by liangye and Risager.The total contents of flavonoids in fresh leaves reach 231 70 mg/100 g,170 01 mg/100 g and 78 07 mg/100 g respectively.In the same circumstance the oven dried leaves were 397 82 mg/100 g,275 89 mg/100 g and 169 73 mg/100 g.The extracts of the leaves from Brodtrop exhibited strong antioxidant activities on lard,which increased with the addition amount of the flavonoid extracts.The antioxidant activities decreased in the order of 0 02% quercetin >0 02% BHT(butylated hydroxy toluene)>0 40% extracts>0 20% extracts>0 10% extracts>0 05% extracts>0 02% extracts>control.展开更多
Many photosynthetic characteristics of three plum varieties were studied with a infrared CO2 analyzer. Results showed that plums belong to light - loving species, having a relative high light compensation point (75-80...Many photosynthetic characteristics of three plum varieties were studied with a infrared CO2 analyzer. Results showed that plums belong to light - loving species, having a relative high light compensation point (75-80μmol· m-2·s-1). In natural light range from none to 1400μmol·m-2s-1PAR,the light response curve of plum as a hyperbo and the net photosynthetic rate(Pn) in leavs increased with PA elevation. Pn of plum tree was 20 to 22.50mg CO2·dm-1·h-1 at 1380μpol. m-2·s-1 PAN,indicating that plum was typi- cal C3-type fruit tree. Diurnal change in Pn was a bimoal curve with the highest photosynthetic rate arising at about 10:00 a. m. indicated the clear 'none - rest 'characteristic in plum leaves. Among three varieties. SuiLi3 had the shortest 'none - rest' time followed by JiLin6 and NuXinLi. Seasonal change in Pn was a bi- modal curve with the first period of high Pn in late June and the second in late August. Pn in leaves decreased visibly in period of drought in Spring and Summer.展开更多
文摘The fresh leaves and oven dried leaves from three varieties of black currant (Brodtrop,liangye,Risager)were analysed for the total contents of flavonoids by spectrophotometric methods in terms of rutin equivalent.In addition,antioxidant activities of different addition amounts of extracts of black currant (Brodtrop)leaves in lard were measured by the Oven-Storage Test,and compared with the synthetic antioxidants.The results showed the contents of the flavonoids were very rich in the leaves of three varieties from black currant.Among them the leaves of Brodtrop had the highest contents of flavonoids followed by liangye and Risager.The total contents of flavonoids in fresh leaves reach 231 70 mg/100 g,170 01 mg/100 g and 78 07 mg/100 g respectively.In the same circumstance the oven dried leaves were 397 82 mg/100 g,275 89 mg/100 g and 169 73 mg/100 g.The extracts of the leaves from Brodtrop exhibited strong antioxidant activities on lard,which increased with the addition amount of the flavonoid extracts.The antioxidant activities decreased in the order of 0 02% quercetin >0 02% BHT(butylated hydroxy toluene)>0 40% extracts>0 20% extracts>0 10% extracts>0 05% extracts>0 02% extracts>control.
文摘Many photosynthetic characteristics of three plum varieties were studied with a infrared CO2 analyzer. Results showed that plums belong to light - loving species, having a relative high light compensation point (75-80μmol· m-2·s-1). In natural light range from none to 1400μmol·m-2s-1PAR,the light response curve of plum as a hyperbo and the net photosynthetic rate(Pn) in leavs increased with PA elevation. Pn of plum tree was 20 to 22.50mg CO2·dm-1·h-1 at 1380μpol. m-2·s-1 PAN,indicating that plum was typi- cal C3-type fruit tree. Diurnal change in Pn was a bimoal curve with the highest photosynthetic rate arising at about 10:00 a. m. indicated the clear 'none - rest 'characteristic in plum leaves. Among three varieties. SuiLi3 had the shortest 'none - rest' time followed by JiLin6 and NuXinLi. Seasonal change in Pn was a bi- modal curve with the first period of high Pn in late June and the second in late August. Pn in leaves decreased visibly in period of drought in Spring and Summer.
