Analysis And Evaluation Of Fruit Nutritional Quality And Study On The Characteristics Of Proanthocyanidins In Cerasus Humilis Germplasm Resources

Cerasus humilis belongs to a very low deciduous shrub belonging to the cherry family of the Rosaceae family.It is a unique wild fruit tree resource in our country.It integrates fruits,seeds and leaves into a body and has very high nutritional value,medicinal value and ecological value,with broad prospects for development.In this study,32 kinds of C.humilis germplasm resources were used as experimental materials,16quality traits of C.humilis fruit were studied,and the fruit quality traits were comprehensively evaluated through difference,correlation,principal component and cluster analysis,so as to further select the C.humilis resources with excellent nutritional quality,and provide theoretical basis for the innovative utilization of C.humilis germplasm resources in Inner Mongolia.1.The fruit sugar and acid quality,phenolic substances,antioxidant activity,calcium and each component,selenium content and flesh color variation coefficient of 32 C.humilis germplasm resources were high,and the genetic diversity was rich.Correlation analysis showed that phenolic substances were closely related to antioxidant activity and pulp color,and were the main antioxidant active substances in C.humilis fruit.Among them,proanthocyanidins were more correlated and had the most prominent antioxidant activity.2.Six principal components（F₁～F₆）were extracted from 14 nutritional indexes of C.humilis fruit by principal component analysis,and the cumulative contribution rate was85.39%.The comprehensive evaluation mathematical model was established,and the top10 C.humilis resources with comprehensive scores had excellent comprehensive nutrition quality.Using standardized quality indexes as parameters,four kinds of C.humilis resources with excellent comprehensive quality and outstanding nutritional quality were selected.3.The C.humilis resources MY11 and MY20 were selected by systematic clustering based on the content of proanthocyanidin,representing the plateau anthocyanidin resources and low proanthocyanidin resources respectively.The contents of proanthocyanidin in different parts of plateau anthocyanidin resources at different periods were higher than those of low proanthocyanidin resources under the same conditions.The procyanidin content in different parts of the fruit was in line with the rule of hard ripening stage>complete ripening stage.The highest procyanidin content was found in the skin at different ripening stages,and in the stem at hard ripening stage>in the flesh,but the opposite was true at complete ripening stage.4.The antioxidant activities of proanthocyanidin standard,C.humilis fruit proanthocyanidin standard（CFPC）,vitamin C（VC）standard and vitamin E（VE）standard were positively correlated with their own concentrations.When the concentration was above 6μg/m L,the·OH clearance rate,DPPH·clearance rate and ABTS⁺·clearance rate of CFPC were higher than those of VC and VE standard substance,and the antioxidant activity of CFPC was prominent in the free radical scavenging ability.5.The C.humilis fruits at hard ripening stage and complete ripening stage all contain PCB1,PCB2,PCB3 and PCC1,among which the content of PCB1 is the highest.Most of the four OPC contents showed that the hard ripening stage was significantly higher than the complete ripening stage.6.The content of proanthocyanidin in C.humilis fruit showed a trend of increasing gradually after harvest,and the contents of PCB1,PCB2,PCB3 and PCC1 showed a trend of increasing first and then decreasing.On the 28th day after harvest,the contents of PCB1 and PCB3 were higher than that on the 0th day,while the contents of PCB2 and PCC1 were lower than that on the 0th day.The content of proanthocyanidin in fruits treated with 2%citric acid and 2% calcium chloride was significantly higher than that of control at the 28th day after harvest,and the decline of PCB1,PCB2,PCB3 and PCC1contents was significantly delayed.