Study On Qualities And Antioxidant Activities Of Lotus Seed And Lotus Leaf In Bai-yang Lake

Lotus is one of the most important ornamental and edible plants in Bai-yang Lake.Withered lotus canopy and lotus leaf are liable to pollute the river course and affect the water quality,which not only wastes lotus resources,but also causes serious damage to the ecological environment of Bai-yang Lake.Taking lotus seed and lotus leaf from Baiyang Lake as experimental materials,the paper mainly studied::(1)qualities and antioxidant activities of different parts of lotus seed;(2)correlation between individual size and physiological characteristics and quality of lotus seed and lotus leaf curl;(3)qualities and antioxidant activities of lotus leaf wax layer treatment and lotus petioles;(4)the effects of drying methods on lotus leaf quality and antioxidant ability;(5)the differences in physiological characteristics,qualities and antioxidant activities of lotus leaf in different regions;(6)effects of picking periods on qualities and antioxidant activities of lotus leaf.The purpose of this study was to improve the medicinal and edible value of lotus seed and lotus leaf.The specific results were as follows:1.Qualities and antioxidant activities of different parts of lotus seed.The experiment mainly assessed qualities and antioxidant activities in different parts of lotus seed(cotyledon,plumule,seed skin and seed epicarp).Cotyledon and plumules contained the higher contents of alkaloids,amino acids,soluble sugar and protein,and the higher activities in superoxide radical scavenging.Seed skin and epicarp had the higher contents of flavone,soluble sugar(except for epicarp)and vitamin C,and the higher activity in DPPH radical scavenging.These results indicated that every part of the lotus seed had different nutritional value and different antioxidant potential,so should be fully exploited and utilized.2.Study on the correlation between individual size and physiological characteristics and quality of lotus seed and leaf roll.Lotus Seed(LS)were graded into three different size groups according to the diameter(0.8-1.0 cm,10.-1.2 cm,1.2-1.4 cm),and lotus leaf curl(LLC)were graded into four different size groups according to the length(10-15 cm,15-20 cm,20-25 cm,25-30 cm),respectively.Comprehensive analysis revealed that:(1)LS1 contained the higher alkaloid,flavone,amino acids,soluble sugar content;(2)LLC4 contained the higher flavone,soluble sugar and protein content;(3)Flavone and alkaloid content in LLC were the higher than that in LS.However,soluble sugar,amino acid,and protein content in LS were the higher than that in LLC.Therefore,when lotus seed and lotus leaf were used for food or medical purposes,their specific size should be considered.3.Study on the physiological characteristics,qualities and antioxidant activities of lotus leavf wax layer treatment and lotus petioles.Blade were used to remove the wax layer on the surface of the lotus leaf.The results showed that: the active and nutritional ingredients(except for vitamin C content)of the unpolished lotus leaf were significantly higher than that of the polished lotus leaf.The antioxidant activities of the polished lotus leaf were significantly higher than that of the unpolished lotus leaf.Lotus petioles showed high alkaloid content.Therefore,lotus petioles are extremely valuable and to-be-developed.4.The effects of drying methods on the quality and antioxidant activity of lotus leaf.The drying methods used in the experiment were microwave drying,Oven drying and steam kill-enzyme torrefaction.The results indicated that:(1)alkaloids and amino acids content in lotus leaf acquired the maximum value when the oven drying temperature was about 55–65°C;(2)The higher contents of protein,soluble sugar and vitamin C in lotus leaf were retained by microwave treatments,and the optimal microwave power and microwave time were about 650-850W(W2-W3)and 3-6min,respectively;(3)The optimal time of steam kill-enzyme was about 3–5min,which retained the higher contents of flavone;(4)The color of lotus leaf treated with microwave treatments was more bright green than that treated with the other two methods;(5)The DPPH radical and the superoxide radical scavenging activity in lotus leaf were the highest by steam kill-enzyme torrefaction,respectively.Thence,the specific conditions of each drying mean should be considered when selecting the drying means.5.The differences in physiological characteristics,quality and antioxidant activities of lotus leaf in different regions.Seven representative sampling areas were selected in the experiment.Different areas significantly affect the quality and antioxidant activities of the lotus leaf.The comprehensive analysis showed that the lotus leaf in Shaochedian area contained the higher contents of active and nutrients ingredients.The lotus leaf in the area of the Datianzhuang had the higher antioxidant activities.The research had practical application value and provided a new basis and reference for the best pick area of the lotus leaf in Baiyang Lake.6.Qualities and antioxidant activities of lotus leaf affected by picking period.The picking period of this test was from June to October.The growth period of lotus leaf significantly affected the quality and antioxidant ability of lotus leaf.The results showed that the contents of alkaloids and flavonoids and antioxidant activities in lotus leaf picked in August were higher.The lotus leaves have high levels of nutrients contents in September and October.The research had practical application value and provided a new basis and reference for when to pick the lotus leaf.The study further broadens the research field of lotus seed and lotus leaf and improves the utilization value of lotus canopy and lotus leaf.This study will promote the sustainable and healthy development of lotus seed and lotus leaf,help the protection of Bai-yang Lake ecological environment and improve the construction of Xiongan New Area.