Quality assessment of rose tea with different drying methods based on physicochemical properties, HS-SPME-GC-MS, and GC-IMS.

The purpose of this study is to compare the physicochemical properties and volatile flavor compounds of rose tea obtained by the methods of normal temperature drying, hot-air drying (HAD), and vacuum freeze-drying (VFD) and to evaluate the quality of rose tea. The physicochemical results showed that the content of ascorbic acid (VC) and the pH value was the highest in rose tea obtained by HAD. The contents of anthocyanin, proanthocyanidins, and total phenols were highest in rose tea obtained by VFD. However, there was no significant difference in total flavonoids between drying methods. The volatile organic compounds (VOCs) in rose tea with different drying methods were analyzed by headspace solid-phase microextraction-gas chromatography-mass spectroscopy (HS-SPME-GC-MS) and HS GC-ion mobility spectroscopy (HS-GC-IMS), and the flavor fingerprint of rose tea was established by principal component analysis (PCA). The concentration of VOCs in rose tea varied greatly with different drying methods. The main flavor compounds of rose tea were alcohols, esters, aldehydes, and terpenoids. HS-GC-IMS was used for the identification of volatile flavor compounds of rose tea, thereby helping to assess the quality of rose tea. In addition, the rose tea samples with different drying methods were well distinguished by PCA. This study deepens the understanding of the physicochemical properties and volatile flavor compounds of rose tea with different drying methods and provides a reference for the identification of rose tea with different drying methods. PRACTICAL APPLICATION: This study deepens the understanding of the physicochemical properties and volatile flavor compounds of rose tea with different drying methods and provides a reference for the identification of rose tea with different drying methods. It also provides an effective theoretical basis for consumers to buy rose tea.

[Genetic diversity of 6 species in Polygonatum by SSR marker].

Polygonatum is a genus of the perennial herb family Liliaceae, with great potential in food, medicine and other field. In this study, genetic diversity and cluster structure analysis of 6 species in Polygonatum were investigated the molecular marker technique of simple sequence repeat (SSR). A total of 49 SSR makers were used to study genetic diversity and population structure within 60 germplasm resources which obtained from 38 counties and cities in 14 provinces of China. A total of 211 alleles were identified and the number of alleles ranged from 2 to 10, with an average of 4.306 1 alleles per SSR. The range of polymorphism information content (PIC) varied from 0.731 8 to 0.031 7, with the average of 0.309 6. The cluster analysis classified 60 germplasm resources into four defined groups at the genetic distance value of 0.26, among which most species with relatives were clustered into the same group. Extraordinarily, there were 6 germplasm resources clustered into other species, indicating that the classification of inter-genus and geographical distribution was crossed in Polygonatum. The genetic diversity index of the 4 geographical populations from high to low was: Western region, Central China, Southern China, Eastern China. The population structure analysis, also indicating divided the entire collection into four groups, which was similar to the assignment pattern of cluster structure analysis. These results suggested that the Polygonatum germplasm resources used in this study is rich in relatively high genetic diversity with large variation range, relatively fuzzy boundaries of species. It appeared the phenomenon that there is a difference decreases between the alternate leaf system and the rotation leaf system. The genetic diversity in the western region was higher than that in other regions, and the western region may be the origin center of the genus Polygonatum.

Effects of hyperbaric oxygen on vascular endothelial function in patients with slow coronary flow.

BACKGROUND: To improve therapy for slow coronary flow (SCF), the effects of hyperbaric oxygen (HBO) therapy on vascular endothelial function in SCF patients is the focus of this investigation. METHODS: Ninety-eight patients who exhibited chest discomfort were retrospectively analyzed, and di-agnosed with SCF by coronary artery angiography at the Third Hospital of Hebei Medical University, Shijiazhuang, China from 2014 to 2016. The patients were divided into two groups according to the following treatment: HBO group (n = 48) and the control group (n = 50). Patients in the control group were administrated with conventional treatment, while those in the HBO group were administrated HBO therapy for 4 weeks in addition to conventional treatment. To evaluate the effects of HBO on vas-cular endothelial functions, plasma levels of nitric oxide (NO), calcitonin gene-related peptide (CGRP), endothelin-1 (ET-1), high sensitivity C-reactive protein (hsCRP) as well as endothelial-dependent flow-mediated vasodilation (FMD) of the brachial artery were measured in both groups before and after their respective treatments. RESULTS: There were no significant differences in plasma levels of NO, ET-1, CGRP, hsCRP nor in FMD measurements between the two groups before treatment (p > 0.05). Moreover, the levels of all the parameters measured showed no significant changes before and after treatment in the control group. However, when comparing the control group, FMD and plasma NO and CGRP levels were significantly increased in the HBO group after treatment (p < 0.01), whereas hsCRP and ET-1 levels decreased dramatically (p < 0.001). CONCLUSIONS: The HBO treatment in addition to conventional therapy may significantly improve the vascular endothelial function in SCF patients. (Cardiol J 2018; 25, 1: 106-112).