Effects of Different Steeping Temperatures on the Leaching of Aroma Components in Black Tea by SPME-GC-MS Coupled with Chemometric Method.

Background: Black tea is famous for its unique aroma. The analysis of aroma components has attracted considerable attention worldwide because of its complex chemical composition and low concentration. Objective: Steeping temperature is one of the most important factors affecting the aroma of black tea. This study aims to evaluate the effects of four steeping temperatures [60, 70, 80, and 95°C (boiling water)]. Methods: Two major factors affecting extraction performance, including the type of extraction method [direct headspace injection (HS) and solid-phase microextraction (SPME)] and extraction time (50, 60, and 70 min), were optimized to enrich and analyze the aroma components of Congou black tea by GC-MS. In addition, heuristic evolving latent projection (HELP), an effective chemometric resolution method, was employed to resolve the overlapped peaks. Results: A total of 83 aroma components were tentatively identified by GC-MS, such as alcohol (42.06-50.52%), aldehyde (12.09-15.97%), and hydrocarbon (4.79-15.32%). Linalool and its oxides (25.49-36.24%) were the most abundant aroma components, followed by geraniol (2.55-8.54%), methyl salicylate (1.84-9.50%), and nerol (1.93-4.41%). Conclusions: The black tea steeped at 95°C smelled more pleasant with mild green, roast, and fruity aroma. Moreover, at 80°C, the tea had sweeter fragrance with floral aroma, while steeping at 60 and 70°C resulted in more reinforced woody and fatty aroma. Highlights: A total of 83 aroma components of black tea were tentatively identified by SPME-GC-MS. The overlapped peaks were resolved by the HELP method. Aroma characteristics of different steeping temperatures were revealed.

Main antimicrobial components of Tinospora capillipes, and their mode of action against Staphylococcus aureus.

In this investigation, the antibacterial modes of action of Radix Tinosporae, its major single components, and nine antibiotics with different targets or modes-of-action on Staphylococcus aureus were studied. Metabolic profiles of cultures treated with different medicines were acquired by HPLC/ESI-MS. After HPLC-MS data pretreatment, those profiles acquired were reduced into several MS vectors. Then statistical processing by principal components analysis was carried out upon those vectors, two conclusions could be drawn: (1) the antibacterial mode of action of Radix Tinosporae is similar to that of rifampicin and norfloxacin, which act on nucleic acid; (2) its active components playing main antimicrobial roles on Staphylococcus aureus might be alkaloids, such as palmatine and jatrorrhizine.

Validate antibacterial mode and find main bioactive components of traditional Chinese medicine Aquilegia oxysepala.

Traditional Chinese medicines have been used for thousands of years and are still being used as one of the regular treatments for many diseases. However, their mechanisms were still unknown. In this investigation, a possible procedure combining metabonomics and principal component analysis to investigate antibacterial modes of action and find main antimicrobial component in traditional Chinese medicine, Aquilegia oxysepala, is developed. Metabolic profiles of Staphylococcus aureus treated with nine antibiotics of known modes of action and with A. oxysepala were acquired by HPLC/DAD/ESI-MS. After statistical processing by principal components analysis on metabolic profiles, two conclusions could be drawn: (1) the target of A. oxysepala may be similar to that of lincolmensin, erythromycin, chloromycetin, streptomycin, and acheomycin, whose targets are protein; (2) its bioactive component playing main antimicrobial roles on S. aureus may be maguoflorine.

[Metabonomics and the modernization of traditional Chinese medicine].

The rapid development of systems biology and especially the advances in the high-throughput and comprehensive research technologies and research idea in metabonomics provide new strategies in the analysis of active components in the formula of traditional Chinese medicine (TCM) and pharmacokinetic analysis of their metabolites in vivo. Furthermore, the initiatives of metabonomics may pave a new way to explain the action mode of TCM in the light of modern sciences, while the metabonomic research achievements may contribute to the establishment of a new technique platform for evaluating the efficacy of the formula of TCM.

Screening and analysis of the multiple absorbed bioactive components and metabolites of Dangguibuxue decoction by the metabolic fingerprinting technique and liquid chromatography/diode-array detection mass spectrometry.

Based on the metabolic fingerprinting technique and liquid chromatography/diode array detection mass spectrometry (LC/DAD-MS), a method for rapid screening and analysis of the multiple absorbed bioactive components and metabolites of an oral solution of Dangguibuxue decoction (ODD) in rabbit plasma after oral administration of ODD was developed. The results obtained from a comprehensive comparative analysis of the fingerprints of the ODD and its metabolic fingerprints in rabbit plasma indicated that 46 components in the ODD were absorbed into the rabbit's body. Of them, ten components were tentatively identified from their MS and UV spectra and retention behaviors by comparing the results with the reported literature. They were calycosin-7-O-beta-D-glycoside, (6aR,-11aR)-hydroxy-9,10-dimethoxypterocarpan-3-O-beta-D-glycoside, ononin, L-3-hydroxy-9,10-dimethoxypterocarpan, formononetin, (3R)-7,2'-dihydroxy-3',4'-dimethoxyisoflavan, sedanenolide, E-ligustilide, Z-ligustilide, and Z-butylidenephthalide. In addition, 21 components were only found in the metabolic fingerprints, which suggested that they might be metabolites of some components in the ODD. The findings demonstrated that the proposed method could be used to rapidly and simultaneously analyze and screen the multiple absorbed bioactive constituents and metabolites in a formula of traditional Chinese medicines (TCMs) by comparing and contrasting the chromatographic fingerprints with its metabolic fingerprints. This is very important not only for the pharmaceutical discovery process and the quality control of crude drugs, but also to explain the curative mechanism of TCMs.