为探究不同等级双井绿茶香气物质组成特征,利用顶空固相微萃取-气相色谱-质谱联用技术(Headspace solid-phase micro extraction and gas chromatography mass spectrometry,HS-SPME-GC/MS)对修水县双井银毫、双井绿茶特级、双井绿茶一...为探究不同等级双井绿茶香气物质组成特征,利用顶空固相微萃取-气相色谱-质谱联用技术(Headspace solid-phase micro extraction and gas chromatography mass spectrometry,HS-SPME-GC/MS)对修水县双井银毫、双井绿茶特级、双井绿茶一级和双井绿茶二级四个不同等级的双井绿茶的香气物质进行了检测分析。结果表明,从四个不同等级的双井绿茶中共鉴定出70种香气物质,主要包括醇类、烯烃类、烷烃类、酯类等化合物。不同等级的双井绿茶中香气物质组成及相对含量均有差异,通过主成分分析(Principal component analysis,PCA)和偏最小二乘法-判别分析(Partial least squares-discriminant analysis,PLS-DA),可以有效区分不同等级的双井绿茶。不同等级双井绿茶香气差异主要由反式-β-金合欢烯、香叶醇、水杨酸甲酯、茉莉酮、苯乙醇等14种关键化合物差异引起。在不同等级双井绿茶中关键香气物质表现出不同的分布规律,随着芽叶开展,α-椰油烯、石竹烯及己酸乙酯含量降低,而顺式-3-己烯醇、香叶醇及水杨酸甲酯含量呈增加趋势,芳樟醇、茉莉酮、反式-橙花叔醇含量从低到高,随后含量又迅速下降。本文研究了不同等级双井绿茶中香气物质的组成特征及关键香气物质的分布规律,为今后双井绿茶生产提供了理论依据。展开更多
Lawsonia inermis is a hairless plant growing in various regions of North Africa, the Indian subcontinent, and the Middle East. It possesses many medicinal attributes, including curative properties against infectious d...Lawsonia inermis is a hairless plant growing in various regions of North Africa, the Indian subcontinent, and the Middle East. It possesses many medicinal attributes, including curative properties against infectious dermatoses. This study was carried out to evaluate the phytochemical profile of the crude ethanolic extract of the plant leaves and its fractions as well as their antimicrobial activities. The phytochemical profile was performed using high-performance thin-layer chromatography (HPTLC), gas chromatography-mass spectrometry (GC-MS), and high-performance liquid chromatography (HPLC). Additionally, the phenolic and flavonoid contents were determined using the Folin-Ciocalteu spectrophotometric and the aluminum trichloride methods. Antimicrobial activity was tested using disc diffusion and microdilution methods. The presence of flavonoids, tannins, sterols, and triterpenes was revealed. GC-MS detected twelve compounds main compounds consisting of saturated and unsaturated fatty acids and phenolic and terpenoid compounds among twenty-seven components. HPLC also detected high contents of phenolic acids and flavonoids. The most abundant triterpene and sterols were ursolic acid (around 43.14 g/100g DW, 13.9 g/100g dry weight (DW), and 0.68 g/100g DW) in the crude ethanolic extract of leaves (FeLi), hexane fraction (FHLi) and dichloromethane fraction (FDLi), respectively and, β-sitosterol in FeLi (56.7 mg/100g DW), FHLi (10.55 g/100g DW), FDLi (106.1 mg/100g DW) and butanol fraction (FBLi) (357.4 mg/100g DW). Among the flavonoids, rutin = 3.24 g/100g and quercetin = 0.63 g/100g in the ethanolic extract, rutin = 15.73 g/100g in the dichloromethane fraction, and rutin = 0.23 g/100g) in the aqueous fraction;and among phenolic compounds, caffeic acid (37.65 g/100g DW) and vanillic acid (22.70 g/100g DW) were the most important in the ethyl acetate fraction (FAeLi). All organic fractions exhibited interesting antibacterial and antifungal activities against the tested strains, with the best activity recorded with the dichloromethane and ethyl acetate fractions. The leaf extracts’ phytochemical profile and antimicrobial activity support the use of Lawsonia inermis against infectious skin diseases.展开更多
文摘为探究不同等级双井绿茶香气物质组成特征,利用顶空固相微萃取-气相色谱-质谱联用技术(Headspace solid-phase micro extraction and gas chromatography mass spectrometry,HS-SPME-GC/MS)对修水县双井银毫、双井绿茶特级、双井绿茶一级和双井绿茶二级四个不同等级的双井绿茶的香气物质进行了检测分析。结果表明,从四个不同等级的双井绿茶中共鉴定出70种香气物质,主要包括醇类、烯烃类、烷烃类、酯类等化合物。不同等级的双井绿茶中香气物质组成及相对含量均有差异,通过主成分分析(Principal component analysis,PCA)和偏最小二乘法-判别分析(Partial least squares-discriminant analysis,PLS-DA),可以有效区分不同等级的双井绿茶。不同等级双井绿茶香气差异主要由反式-β-金合欢烯、香叶醇、水杨酸甲酯、茉莉酮、苯乙醇等14种关键化合物差异引起。在不同等级双井绿茶中关键香气物质表现出不同的分布规律,随着芽叶开展,α-椰油烯、石竹烯及己酸乙酯含量降低,而顺式-3-己烯醇、香叶醇及水杨酸甲酯含量呈增加趋势,芳樟醇、茉莉酮、反式-橙花叔醇含量从低到高,随后含量又迅速下降。本文研究了不同等级双井绿茶中香气物质的组成特征及关键香气物质的分布规律,为今后双井绿茶生产提供了理论依据。
文摘Lawsonia inermis is a hairless plant growing in various regions of North Africa, the Indian subcontinent, and the Middle East. It possesses many medicinal attributes, including curative properties against infectious dermatoses. This study was carried out to evaluate the phytochemical profile of the crude ethanolic extract of the plant leaves and its fractions as well as their antimicrobial activities. The phytochemical profile was performed using high-performance thin-layer chromatography (HPTLC), gas chromatography-mass spectrometry (GC-MS), and high-performance liquid chromatography (HPLC). Additionally, the phenolic and flavonoid contents were determined using the Folin-Ciocalteu spectrophotometric and the aluminum trichloride methods. Antimicrobial activity was tested using disc diffusion and microdilution methods. The presence of flavonoids, tannins, sterols, and triterpenes was revealed. GC-MS detected twelve compounds main compounds consisting of saturated and unsaturated fatty acids and phenolic and terpenoid compounds among twenty-seven components. HPLC also detected high contents of phenolic acids and flavonoids. The most abundant triterpene and sterols were ursolic acid (around 43.14 g/100g DW, 13.9 g/100g dry weight (DW), and 0.68 g/100g DW) in the crude ethanolic extract of leaves (FeLi), hexane fraction (FHLi) and dichloromethane fraction (FDLi), respectively and, β-sitosterol in FeLi (56.7 mg/100g DW), FHLi (10.55 g/100g DW), FDLi (106.1 mg/100g DW) and butanol fraction (FBLi) (357.4 mg/100g DW). Among the flavonoids, rutin = 3.24 g/100g and quercetin = 0.63 g/100g in the ethanolic extract, rutin = 15.73 g/100g in the dichloromethane fraction, and rutin = 0.23 g/100g) in the aqueous fraction;and among phenolic compounds, caffeic acid (37.65 g/100g DW) and vanillic acid (22.70 g/100g DW) were the most important in the ethyl acetate fraction (FAeLi). All organic fractions exhibited interesting antibacterial and antifungal activities against the tested strains, with the best activity recorded with the dichloromethane and ethyl acetate fractions. The leaf extracts’ phytochemical profile and antimicrobial activity support the use of Lawsonia inermis against infectious skin diseases.