Study On Volatile Components In Hainan Mallotus Oblongifolius

Mallotus oblongifolius is a tropical plant belongs to Euphorbiaceae.This plant,native to regions of Hainan Island in China,is economically important and medicinally relevant.Because of its unique aroma and medicinal properties such as anti-inflammatory,cholagogic and promote digestion,it is very popular with the local people.The aroma components of Mallotus oblongifolius may be related to the morphology,maturity,season and processing method of the collected leaves.In this study,the headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry(HS-SPME / GC-MS)technology was used to extract and identify volatile components of Mallotus oblongifolius with different leaf color types(red leaves,green leaves),different maturity(young leaves,mature leaves)and different harvest seasons(spring,summer,autumn and winter).At the same time,the differences of volatile components between Mallotus oblongifolius produced by different processing methods(Finish machining and Rough machining)and and their differences with Hainan Baisha green tea were compared.The volatile components detected are mainly olefin compounds,and the main research results are as follows:(1)In the red leaves,the volatile components of young leaves were mainlyα-Guaiene(14.34%)in spring,caryophyllene(15.60%)in summer,caryophylene(22.50%)in autumn,and(1S)-(1)-beta-Pinene(13.81%)in winter.The volatile components of mature leaves were mainly α-Copaene(6.95%)and α-Guaiene(6.84%)in spring,α-Guaiene(8.74%)and beta-Bourbonene(6.60%)in summer,δ-Cadinene(3.88%)and caryophyllene(3.82%)in autumn,γ-Muurolene(2.91%)in winter.(2)In the green leaves,the volatile components of young leaves were mainlyδ-Cadinene(9.90%)and γ-Muurolene(8.76%)in spring,mainly α-Copaene(13.97%)and α-Guaiene(11.08%)in summer,mainly α-Copaene(14.69%)and caryophyllene(14.19%)in autumn,mainly(+)-α-Pinene(8.60%)and(1S)-(1)-beta-Pinene(7.41%)in winter.The volatile components of mature leaves were mainly α-Copaene(4.52%)in spring,(1S)-(-)-α-Pinene(7.32%)in summer,caryophyllenes(10.76%)in autumn,andγ-Elemene(7.18%)in winter.(3)Total volatile compounds in red leaves and green leaves in different seasons:young leaves of red leaves and green leaves were higher than mature leaves of red leaves and green leaves,and the total volatile compounds in young red leaves in summer(91.92%in summer)was the highest.The types and relative contents of volatile components in spring and summer are much higher than that in autumn and winter.(4)In the finished tea,the volatile components of Mallotus oblongifolius are mainly alkenes,among which the total volatile components in finish machining(27.56%)are less than that in rough machining(87.59%).27 volatile components were identified by finish machining,mainly E-2-Hexenal(8.84%).29 volatile components were identified,mainly(+)-alpha-Pinene 34.35%).Fifteen volatile components were identified in baisha green tea,mainly D-limonene(9.67%).