Aim
To establish a fast, sensitive and accurate high‐performance liquid chromatography‐tandem mass spectrometry (HPLC‐MS/MS) method for determining the monosaccharide content of Qingzhuan Dark Tea polysaccharides in different years (2 years, 5 years and 11 years).
Methods
The optimised chromatographic conditions were achieved on a C18 column (5.0 μm, 250 mm × 4.6 mm inner diameter). The mobile phase flow rate was 0.9 mL/min and the column temperature was set to 27°C. The aqueous phase A (5 mM aqueous ammonium acetate) and organic phase B (acetonitrile) were used to elute the target analyses isocratically (0–60 min: 18% B). The mass spectrometer detector was equipped with an electron spray ionisation (ESI)source, and multiple reaction monitoring (MRM) mode was used for the determination of 1‐phenyl‐3‐methyl‐5‐pyrazolone (PMP) derived monosaccharides.
Results
We carried out a comprehensive methodological validation of PMP derived monosaccharides, including linearity, precision, stability and repeatability. Nine monosaccharides (rhamnose, mannose, ribose, glucose, galacturonic acid, xylose, galactose, fucose and arabinose) of Qingzhuan Dark Tea polysaccharides were identified, in which ribose and fucose were reported for the first time. The results showed the contents of these nine monosaccharides differed significantly among different years.
Conclusions
The validated method is reliable, accurate, repeatable and can be applied to quality assessment of these monosaccharides.
The physiological health and chronic diseases of humans can be monitored by linking up health management and monitoring (HMM) system with the Internet of things (IoT), which transcends the restrictions of time and space. However, the IoT network faces several resource constraints, such as limited storage and initial energy of nodes, long delay of response to system transmission, and low rate of successful payments. To solve these problems, this paper explores the IoT-based implementation of universal HMM system in resource-constrained environment. Firstly, the forwarding utility of the communication between adjacent IoT nodes was estimated, and an incentive strategy was prepared for the IoT nodes in the resourceconstrained environment. Next, a universal HMM system was designed, and the scheme for denoising, baseline drift filtering, and feature point detection was introduced step by step. After that, the authors presented the design process of the communication protocol, and the workflow of the cloud server. Through experiments, the measurements of the detection modules in the proposed universal HMM system were proved effective, and our algorithm was confirmed superior in the success rate of message delivery, the mean residual energy of nodes, and the delay of system response.INDEX TERMS Internet of things (IoT) network, universal health management and monitoring (HMM) system, resource-constrained environment
Tea polysaccharides was one of the active ingredients of Qingzhuan dark tea, which had antioxidant, anti-tumor, and immuneenhancing effects. The complexation of metal ions of tea polysaccharides was one of the current research hotspots. It can combine the advantages of tea polysaccharides and their complexed trace metal elements, and had great potential development. In this study, the trace element-copper required by the human body was used for complexation with Qingzhuan dark tea polysaccharides, and the structure was characterized by various chemical methods. The copper complexes of Qingzhuan dark tea polysaccharides were characterized by UV spectroscopy, FT-IR, thermogravimetric analysis, X-ray diffraction (XRD), SEM, AFM and X-ray photoelectron spectroscopy (XPS). The tests results show that it was successfully complexed with tea polysaccharides. Meanwhile, the Qingzhuan dark tea polysaccharides copper complex compound (termed TPS-Cu) showed higher scavenging activity of hydroxyl radical and ABTS free radical than the tea polysaccharides (termed TPS). Therefore, TPS-Cu can be used as a potentially effective and stable copper supplement and preventive agent.
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