Effects Of Different Harvest Time And Shading On Medicinal Quality Of Pyrrosia Petiolosa

Pyrrosia Petiolosa is a plant belonging to the family Polypodiaceae Pyrrosia.It is used as medicine with dried leaves.It has the functions of diuresis,leaching,clearing the lungs and relieving cough.It is the main raw material of Chinese patent medicines such as"Jieshitong Tablets"and"Compound Pyrrosia Tablets".The main active ingredients are phenols and flavonoids.The preliminary investigations have shown that the harvest period and light are important factors affecting the quality of medicinal materials,but there are few studies related to them.This article takes P.petiolosa as the research object,to compare and analyze the content of total flavonoids,total phenols,chlorogenic acid,neochlorogenic acid and antioxidant activity in different months.Simultaneously,different shading was carried out to simulate its habitat,and the effects of shading on the growth and quality of P.petiolosa were studied.The results provided a basis for artificial cultivation,rational utilization and quality stability of P.petiolosa.The main research results are as follows:(1)The content of active ingredients and antioxidant activity of P.petiolosa showed obvious seasonal changes.Studies have shown that the contents of total flavonoids,total phenols and chlorogenic acid all increased from December in winter to the highest value from March to April in spring of the following year,and slowly decreased from July in summer to November in autumn.The content of active ingredient in this month is the lowest.the content of total flavonoids in March was the highest,as high as 161.78 mg/g.The content of total phenols in April was the highest,which was 61.31 mg/g.The content of chlorogenic acid in April was higher,as high as 14.99 mg/g.The content of neochlorogenic acid in July was higher,which was 4.79 mg/g.The content of active ingredients in the leaves harvested in spring was highest.Spring is the period of vigorous sprouting of the leaves,while the content of active ingredients and antioxidant capacity of the leaves harvested in summer is higher than that in autumn and winter.Therefore,considering the output and quality,it is recommended that summer is the best harvesting season.(2)There are significant differences in the content of active ingredients and antioxidant activity in different parts of P.petiolosa.In this study,the content of active ingredients in trophophylls and sporophylls was much higher than that of petiole.The content of chlorogenic acid and neochlorogenic acid in trophophylls was the highest,followed by sporophylls,and petiole was the lowest.In the same month,the highest difference of chlorogenic acid content between trophophylls and sporophylls was 2.82 mg/g,and the antioxidant capacity of ethanol extracts from trophophylls is stronger.So it is suggested to use trophophylls as the main harvesting part.(3)P.petiolosa has a strong ability to adapt to weak light,but suitable strong light can promote leaf growth.Studies have shown that the F_v/F_m value has little change under different shading,and there is no significant difference in chlorophyll content and net photosynthetic rate,indicating that P.petiolosa is adapted to a wider range of light.Light shading(50%light transmittance)environment is more suitable for leaf growth than heavy shading(10%light transmission).The number of leaves,growth rate,leaf length,leaf width,and leaf area of the light shading treatment were significantly higher than those of the heavy shading.When the plant moved from the heavy shading environment to the light shading,plant growth indicators have increased.When the plant moves from light shade to heavy shade,leaf growth is inhibited.(4)Light shading is conducive to the accumulation of total flavonoids content of P.petiolosa,which affects its antioxidant activity.The content of total flavonoids in light shading was significantly higher than that of the heavy shading,and the results of antioxidant activity analysis were consistent with that of total flavonoids.When the plant is transferred from light shaded environment to heavy shaded environment,the total flavonoids content is reduced,and the antioxidant activity is weakened.When the plants were transferred from heavy shaded environment to light shaded environment,the total flavonoids content is increased.Therefore,it is recommended to choose light shaded environment to cultivate P.petiolosa.