Study On The Change Law Of Secondary Substances Of Meliosma Cuneifolia

Meliosma cuneifolia Franch（M.cuneifolia）belongs to the Meliosma of Sabiaceae,deciduous shrubs or macrophanerophytes.It is a precious tree species in China,which is suitable to live in moist and fertile sandy soil with good drainage effect,and likes warm-humid climate.M.cuneifolia has a good application value.It has beautiful flowers and leaves,which is suitable for isolated or group planting in parks and green spaces.Its leaves can be used in cosmetics,which have good sun-proof,whitening and moisturizing effects on the skin.Its barks can be peeled for fiber,which can also be used as medicine.Its woods are reddish brown with fine structure and light weight,which is one of the excellent materials for building and furniture.However,the research on M.cuneifoklia is very few,and the development and utilization of its high value-added products is insufficient,which is not conducive to the sustainable protection and utilization of M.cuneifolia resources.Therefore,TD-GC/MS,TG-FTIR,QTOF-LC/MS and other modern analysis methods were used in this study to explore the change rules of secondary biomass in the parts of M.cuneifolia,and reveal the anticancer rules of secondary biomass,provide theoretical basis for the development of anticancer drugs and technical support for the protection and sustainable high-value utilization of M.cuneifolia resources.The results are as follows:（1）Study on the variation of volatile secondary substances of M.cuneifolia:TG、TG-FTIR and TD-GC/MS were used to study the variation of volatile secondary substances in different parts（barks,woods,roots,and root barks）of M.cuneifolia.TGA results show that the pyrolysis process of the powders can be divided into three stages,in which the initial stage is mainly the evaporation of liquid water molecules;the second stage is an important stage of the pyrolysis process,in which the weight loss rate changes greatly and a lot of substances are precipitated;in the third stage,slight pyrolysis occurs,mainly some high temperature resistant substances are precipitated.Below 200℃ is the initial stage of the pyrolysis process and the mass loss accounts for 15%of the total weight loss,which is mainly due to the volatilization of water molecules and some small molecular substances in different parts of M.cuneifolia.With the increase of temperature,volatile compounds and mass loss increased gradually.TG-FTIR detection is based on the TG detection,and the pyrolysis experiment was carried out at the heating rate of 25℃/min.It can also be divided into different stages.The preheating stage is at 200℃.In this stage,the mass loss of the sample is less,and the stretching vibration trend of the peak in the infrared spectrum is relatively slow.With the increase of temperature,the pyrolysis process and the change trend of infrared spectrum become more complex.TD-GC/MS results showed that 90 compounds were identified in the barks,100 compounds in the woods,102 compounds in the roots,79 compounds in the root barks and there are 21 kinds of the same active components in the four parts.（2）Study on the change law of soluble secondary substances of M.cuneifolia:FT-IR,GC-MS and QTOF-LC/MS were used to detect the components and structures of three dissolved secondary substances（ethanol,benzyl alcohol and methanol）in different parts of M.cuneifolia.The results of FT-IR showed that the absorption peaks of dissolved secondary substances in different parts of M.cuneifolia were mainly concentrated in the range of 3400-3250 cm^-1,3000-2850 cm^-1,1650-1000 cm^-1.The results showed that there were hydrocarbons（saturated and unsaturated hydrocarbons）,phenols,aldehydes and ketones.The results of GC-MS showed that for barks,28,23 and 25 chemical components were identified for ethanol,benzyl alcohol and methanol;In woods,18,16 and 21 chemical components were identified for ethanol,benzyl alcohol and methanol;In roots,26,33 and 22 chemical components were identified for ethanol,benzyl alcohol and methanol;In root barks,16,22 and 20 chemical components were identified from ethanol,benzyl alcohol and methanol,and some of them were relatively high in different extracts of different parts.The results of QTOF-LC/MS showed that 143 and 157 chemical components were identified in the ethanol and methanol soluble secondary metabolites of barks,103 and 136 chemical components were identified in the ethanol and methanol soluble secondary metabolites of woods,122 and 113 chemical components were identified in the ethanol and methanol soluble secondary metabolites of roots,121 and 153 chemical components were identified in the ethanol and methanol soluble secondary metabolites of root barks.In particular,the soluble secondary substances in different parts of M.cuneifolia have a large content of active components such as aesculin,phytolac saponin A,Picroside IB and deoxycholic acid,which have good application prospects in the field of medicine.（3）Study on cytotoxicity of secondary substances of M.cuneifolia:The results of MTT showed that the soluble secondary substances from different parts of M.cuneifolia（barks,woods,roots and root barks）had cytotoxicity on HepG2,K562 and SGC-7901 cancer cells,and the secondary substances from barks and woods extracts had the highest lethal rate on HepG2 cells,which were 82.209%and 91.865%,respectively.The lethality rate of the secondary substance of roots extracts on K562 cells was the highest,49.060%.The lethality rate of the secondary substance of root barks for SGC-7901 cells was 63.805%.The cytotoxicity of different parts of M.cuneifolia is:Woods>barks>root barks>roots,and the cytotoxicity of barks and woods of M.cuneifolia is much higher than that of roots and root barks,which provides a theoretical basis for the research and developent of new anticancer drugs of M.cuneifolia.