Study On The Changes Of Flavonoids In Different Leaves Of Zanthoxylum Bungeanum

Zanthoxylum bungeanum is an important economic tree of the genus Zanthoxylum.As early as in ancient China,the Zanthoxylum bungeanum peel was widely used as a flavoring.As a wide-ranging deep processing resource,Zanthoxylum bungeanum is still playing an important application value in the food industry.The leaves of Zanthoxylum bungeanum is a by-product of Zanthoxylum bungeanum,which can be used as seasoning or Zanthoxylum bungeanum tea,which has the functions of driving wind,sweating,bacteriostatic and insecticidal.According to records,in Shaanxi and Guizhou provinces,the residents of the area have long been accustomed to eating spicy foods,so the Zanthoxylum bungeanum leaves as a new type of fresh food has been widely loved.Flavonoids are widely found in nature and are important components of many Chinese herbal medicines and medicinal plants.They have anti-oxidation,anti-cancer,anti-tumor,anti-inflammatory,anti-cardio-cerebral vascular diseases,immune regulation,antibacterial and antiviral,hypoglycemic Lowering blood lipids and other pharmacological effects.Studies have shown that the seeds,stems,peels and leaves of Zanthoxylum bungeanum are rich in flavonoids,and there are relatively few studies on the leaves of Zanthoxylum bungeanum.Therefore,the types and physiological functions of the flavonoids contained in the Zanthoxylum bungeanum need to be further explored.In order to compare the differences between the flavonoids of different varieties and seasons of Zanthoxylum bungeanum,three different varieties of Zanthoxylum bungeanum leaves in the same growing region and year were selected as the research objects,and the flavonoids content of Zanthoxylum bungeanum leaves and its climatic factors affecting growth were studied.The research and the determination of the main flavonoids in the leaves of Zanthoxylum bungeanum were determined by high-performance liquid-mass spectrometry.The purpose of this study was to understand the difference and seasonal variation of flavonoids in different varieties of Zanthoxylum bungeanum leaces under the same growth conditions,which is more rational and effectivet to give a theoretical datebases for the growing and application of Zanthoxylum bungeanum resources.The main findings are as follows:(1)The flavonoids in the leaves of Zanthoxylum bungeanum were extracted by ultrasonic extraction.The analysis conditions were as follows: the ratio of solid to liquid was1:30,the extraction solvent was 80% methanol,the extraction temperature was 50 °C,and the extraction time was 40 min.Under this extraction conditions,the average yield of totalflavonoids in the leaves of Zanthoxylum bungeanum was up to 1.56%,indicating that the extraction method is simple,rapid and the extraction effect is good.(2)The content of total flavonoids in different varieties of Zanthoxylum bungeanum leaves showed significant seasonal changes,and its content fluctuated greatly in different months or at different times in the same month,showing the trend of “rapid rise-rapid decline-slow rise-rapid decline”.In 2017,the total flavonoids content of Zanthoxylum bungeanum leaves reached the maximum in mid-June.At this time,the total flavonoids content of Meifengjiao,Qinan Yihao and Shizitou respectively reached 13.74mg/g,14.01mg/g and 14.77mg/gmg/g.In 2018,the total flavonoids content of Zanthoxylum bungeanum leaves reached the maximum in mid-July.At this time,the total flavonoids content of Meifengjiao,Qinan Yihao and Shizitou respectively reached 22.123mg/g,12.16mg/g and 25.15mg/g.Considering the leaf yield and total flavonoid content,it is recommended that the suitable harvesting period of the leaves is 6 and 8 months.(3)The content of flavonoids in Zanthoxylum bungeanum leaves is closely related to meteorological factors.When the average temperature reaches 10-14 ?,it shows a good growth,and it is more suitable for the growth of Zanthoxylum bungeanum.Under the condition that the annual precipitation is more than 500 mm and the geographical distribution is relatively uniform,it can meet its growth and development.Especially from April to May,it is very sensitive to moisture requirements,and the precipitation is between 80-150 mm,which is suitable for the water demand of the Zanthoxylum bungeanum flowering to the fruiting stage.In the same year,the sunshine hours reached 1800-2000 h,the sunshine duration in the growing season reached 1200 h or more,and the sunshine percentage was50%-60%,which was most suitable for Zanthoxylum bungeanum growth.Especially in July and August,the adequacy of light is a critical period to improve the quality of pepper and increase production.In the coloring mature period,the relative humidity of the air reaches65% to 70%,which is beneficial to the accumulation of biologically active ingredients,and is not volatile,so the quality is the best.(4)There are also significant differences in the content of flavonoids in different varieties of Zanthoxylum bungeanum leaves.By analyzing the content of seven flavonoids in the leaves of Zanthoxylum bungeanum,quercetin,hyperoside and quercetin-3-O-glucoside were the main detective components of these seven flavonoids,followed by Afudou Glycosides,catechins,and the detection levels of epicatechin and rutin are relatively low.It is speculated that quercetin,hyperoside,and quercetin-3-O-glucoside may be the main flavonoids components in the leaves of Zanthoxylum bungeanum,which can be used as anew way to obtain quercetin,quercetin-3-O-glucoside,and hyperoside.