Qingke(highland barley)Baijiu is a special Chinese Baijiu which is mainly produced from Qinghai-Tibet Plateau.Since the pine board is used as the bottom of the fermentation pit,we deduced that the terpenoids and noris...Qingke(highland barley)Baijiu is a special Chinese Baijiu which is mainly produced from Qinghai-Tibet Plateau.Since the pine board is used as the bottom of the fermentation pit,we deduced that the terpenoids and norisoprenoids in pine board might be introduced into Qingke Baijiu.Thus,the terpenoids and norisoprenoids in Qingke Baijiu were investigated by headspace solid phase microextraction(HS-SPME)combined with comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometry(GC×GC-TOFMS).The results showed thatγ-terpinene(0.70-530.72μg/L),α-phellandrene(0.34-256.66μg/L),longicyclene(0-38.55μg/L),α-pinene(1.21-35.54μg/L)and limonene(0.93-23.69μg/L)were the top 5 terpenoids/norisoprenoids in Qingke Baijiu.Pulegone was detected and reported for the first time in Baijiu,and the concentrations in Qingke Baijiu were 0.78μg/L(fresh)and 3.90μg/L(7 years old).According to the principal component analysis(PCA)plot,young,aged,and retail Qingke Baijiu could be differentiated clearly.Fold change(FC)and t-tests analysis indicated thatβ-pinene,γ-terpinene,andα-selinene were the most different terpenoids/norisoprenoids between young and aged Qingke Baijiu,and longifolene was the most different terpenoids/norisoprenoids between base and retail Qingke Baijiu.The terpenoids and norisoprenoids,such as(E)-β-ionone,isoborneol andβ-cyclocitral,could be potential markers indicating the ageing process of Qingke Baijiu.展开更多
Lannea kerstingii is known for its multiple therapeutic and biological activities. Despite of many traditional uses of this plant, scientific research on the content of its chemical compounds is still limited. This st...Lannea kerstingii is known for its multiple therapeutic and biological activities. Despite of many traditional uses of this plant, scientific research on the content of its chemical compounds is still limited. This study aims to isolate the chemical compounds contained in the n-butanol fraction of Lannea kerstingii leaves. The chemical investigation of the leaves of Lannea kerstingii led to isolation of three undescribed C-13 norisoprenoids, lankerstinol A-C (1-3), together with six (4-9) known flavonoid glycosides. The structures of these compounds were established by spectroscopic analyses.展开更多
Two new norisoprenoid derivatives have been isolated from the red alga Gymnogongrus flabelliformis. Their structures were elucidated as （3R, 6R, 7E）-（＋）-3-O-phenylacetyl-4,7-megas- tigmadiene-9-one and （3R,TE）-...Two new norisoprenoid derivatives have been isolated from the red alga Gymnogongrus flabelliformis. Their structures were elucidated as （3R, 6R, 7E）-（＋）-3-O-phenylacetyl-4,7-megas- tigmadiene-9-one and （3R,TE）-（-）-3-O-phenylacetyl-5,7-megastigmadiene-9-one, respectively, by spectroscopic methods including HRMS, 1D and 2D NMR techniques.展开更多
基金financially supported by the National Key R&D Program of China (2016YFD0400500)
文摘Qingke(highland barley)Baijiu is a special Chinese Baijiu which is mainly produced from Qinghai-Tibet Plateau.Since the pine board is used as the bottom of the fermentation pit,we deduced that the terpenoids and norisoprenoids in pine board might be introduced into Qingke Baijiu.Thus,the terpenoids and norisoprenoids in Qingke Baijiu were investigated by headspace solid phase microextraction(HS-SPME)combined with comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometry(GC×GC-TOFMS).The results showed thatγ-terpinene(0.70-530.72μg/L),α-phellandrene(0.34-256.66μg/L),longicyclene(0-38.55μg/L),α-pinene(1.21-35.54μg/L)and limonene(0.93-23.69μg/L)were the top 5 terpenoids/norisoprenoids in Qingke Baijiu.Pulegone was detected and reported for the first time in Baijiu,and the concentrations in Qingke Baijiu were 0.78μg/L(fresh)and 3.90μg/L(7 years old).According to the principal component analysis(PCA)plot,young,aged,and retail Qingke Baijiu could be differentiated clearly.Fold change(FC)and t-tests analysis indicated thatβ-pinene,γ-terpinene,andα-selinene were the most different terpenoids/norisoprenoids between young and aged Qingke Baijiu,and longifolene was the most different terpenoids/norisoprenoids between base and retail Qingke Baijiu.The terpenoids and norisoprenoids,such as(E)-β-ionone,isoborneol andβ-cyclocitral,could be potential markers indicating the ageing process of Qingke Baijiu.
文摘Lannea kerstingii is known for its multiple therapeutic and biological activities. Despite of many traditional uses of this plant, scientific research on the content of its chemical compounds is still limited. This study aims to isolate the chemical compounds contained in the n-butanol fraction of Lannea kerstingii leaves. The chemical investigation of the leaves of Lannea kerstingii led to isolation of three undescribed C-13 norisoprenoids, lankerstinol A-C (1-3), together with six (4-9) known flavonoid glycosides. The structures of these compounds were established by spectroscopic analyses.
文摘Two new norisoprenoid derivatives have been isolated from the red alga Gymnogongrus flabelliformis. Their structures were elucidated as （3R, 6R, 7E）-（＋）-3-O-phenylacetyl-4,7-megas- tigmadiene-9-one and （3R,TE）-（-）-3-O-phenylacetyl-5,7-megastigmadiene-9-one, respectively, by spectroscopic methods including HRMS, 1D and 2D NMR techniques.
