Chemical profiling and multicomponents quantitative analysis of Panzerina lanata by ultra-fast liquid chromatography with tandem mass spectrometry.

Panzerina lanata is a Chinese medicine with the bioactivity of detumescence and detoxification. In this study, novel qualitative and quantitative methods were established by ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry and ultra-high-performance liquid chromatography-triple quadrupole linear ion trap mass spectrometry, respectively. As a result, 20 compounds were identified or tentatively characterized including flavonoids, organic acids, alkaloids, and lignans, five of which were identified for the first time based on the reference standards. The quantitative approach exhibited good linearity (R2  > 0.995), precision (RSDs < 4.97%), stability (RSDs < 4.77%), and recovery (96.04-104.14%). Afterward, this method was implemented to determine 11 flavonoids in four batches of P. lanata. Among them, seven compounds were quantified for the first time. Narcissin was abundant in each batch of P. lanata (average of 10.890-14.230 mg/g) with the highest quantities. The results provide valuable information for quality evaluation.

Directional screening and identification of potential cytotoxic components from Achnatherum inebrians by a combination of surface palsmon resonance and chromatography.

Objective: To establish a method for directional screening of the cytotoxic components from the medicinal herb of Achnatherum inebrians by a combination of surface plasmon resonance (SPR) biosensor and chromatographic isolation technology. Methods: Under the guidance of bioactive assessment based on binding abilities between objects and the α-Mannosidase (α-Man) target, the active components from different solvents extracts, different polar extraction parts and fractions were screened orderly and directionally using SPR. Components with a high binding ability to α-Man can be precisely oriented in a narrower fractions range and are easy to isolate. Three human cancer cells were used to evaluate the cytotoxic activity of component with the highest affinity to α-Man. Results: Eight compounds were isolated and identificated from A. inebrians for the first time. Deoxyvasicinone possessed the highest affinity to α-Man among them. Moreover, deoxyvasicinone showed good effects on inhibited proliferation of human hepatoma cells HepG2 (IC50 = 5.7 µmol/L), human breast cancer cells MCF7 (IC50 = 7.21 µmol/L) and human lung cancer cells HCC827 (IC50 = 0.75 µmol/L), respectively. In particular, its inhibitory effect on HCC827 was stronger than the positive drug gefitinib (IC50 = 1.65 µmol/L). Conclusion: A comprehensive strategy of directional screening potential cytotoxic components from herb based on biomolecular interaction and chromatography was established. Deoxyvasicinone as an effective anti-cancer component was initially isolated from A. inebrians. It is expected that this screening strategy could provide new perspectives for rapid screening and identification of active components from natural plants with the complex matrix.

Comparative analysis of type 2 diabetes-associated gut microbiota between Han and Mongolian people.

Due to the different rates of diabetes in different ethnic groups and the structural differences in intestinal microbiota, this study evaluated the changes in diabetes-related intestinal microbiota in two ethnic groups. Fifty-six stool samples were collected from subjects from the Han and Mongolian ethnic groups in China, including participants without diabetes (non-diabetic, ND) and with type 2 diabetes (T2D). The 16S rDNA gene V3 + V4 area was extracted from microbiota, amplified by PCR, and used to perform high-throughput sequencing and screen differential microbiota associated with ethnicity. The results showed that there were 44 T2D-related bacterial markers in the Han subjects, of which Flavonifractor, Alistipes, Prevotella, Oscillibacter, Clostridium XlVa, and Lachnospiracea_incertae_sedis were most closely related to diabetes. There were 20 T2D-related bacterial markers in the Mongolian subjects, of which Fastidiosipila and Barnesiella were most closely related to diabetes. The common markers of T2D bacteria in the two ethnic groups were Papillibacter and Bifidobacterium. There were 17 metabolic pathways with significant differences between the ND and T2D groups in the Han group, and 29 metabolic pathways in the Mongolian group. The glutamatergic metabolic pathway was the only common metabolic pathway in two ethnic groups. The composition and function of diabetes-related bacteria were significantly different among the different ethnic groups, which suggested that the influence of ethnic differences should be fully considered when studying the association between diabetes and bacteria. In addition, the common bacterial markers found in diabetic patients of different ethnic groups in this study can be used as potential targets to study the pathogenesis and treatment of diabetes.

Capillary GC using pyridyl beta-cyclodextrin stationary phase.

A new beta-CD derivative, heptakis [2,6-di-O-pentyl-3-O-(4'-chloro-5'-pyridylmethyl)]-beta-CD, was synthesized by the selective introduction of a pyridyl group on the 3-positions of beta-CD. The chromatographic properties of the pyridyl beta-CD derivative were studied by using it as the stationary phase in capillary GC. The polarity of the prepared stationary phase was moderate, and the separation results demonstrated that the prepared stationary phase possessed excellent separation ability and chiral recognition for a wide range of analytes. Not only the aromatic positional isomers, such as o-, m-, p-xylene and alpha-, beta-naphthol isomers, but also some compounds with multi-stereogenic centers, such as n-(1-methylpropyl)-3-(2,2-dichloroethenyl)-2,2-dimethylcyclopropanecarboxamide and n-(1-methylpropyl)-3-(2-chloro-3,3,3-trifluoropropenyl)-2,2-dimethylcyclopropanecarboxamide with three stereogenic centers including eight configurational isomers, were successfully separated. The results also indicated that the polarity of the beta-CD derivative, and the hydrogen bonding between the beta-CD derivative, and the analytes had a very important effect on separation.

[Application of fluorescence microscopic imaging technique with self-ordered ring to residues detection of antibiotics].

Fluorescence microscopic self-ordered ring (SOR) technique with microwave heating is proposed for minocycline based on the capillary flow of solvent on the surface of hydrophobic glass slide and applied to residues detection of the antibiotics in milks of Inner Mongolia. In the reaction medium of hexahydropyridine containing polyvinyl alcohol-124 (PVA-124), a SOR of minocycline with the outer diameter of 1.54 mm and the ring belt width of 22.6 microm can be formed. When a 0.30 microL droplet of minocycline mixture was spotted on the solid surface, minocycline in the range of 4.2 x 10(-2)-1.8 x 10(-11) mol x ring(-1) (1.4 x 10(-6)-0.60 x 10(-5) mol x L(-1)) can be detected, the maximum fluorescence intensity was found to be proportional to the minocycline concentration, and the limit of detection can reach 4.2 x 10(-13) mol x ring(-1) (1.4 x 10(-7) mol x L(-1)) with three times of signal to noise ratio. With the present method, the contents of minocycline in milk samples of Inner Mongolia and minocycline hydrochloride capsule sample were satisfactorily determined with recoveries of 97.2%-103% and 99.4%-102%, respectively, and RSD lower than 1.2%, correspondingly. Therefore, a highly sensitive and selective analysis method for detecting content of trace drug contaminations was established. The method provided theory basis to quantificational analysis of the residues of the antibiotics in milks which was Inner Mongolia' preponderant resource products. It has important realistic meaning and broad application prospect.

Correlations between dechlorane plus concentrations in paired hair and indoor dust samples and differences between dechlorane plus isomer concentrations in hair from males and females.

Dechlorane plus (DP) is found widely in environmental media. Determining DP concentrations in dust and hair and identifying relationships between the concentrations in dust and hair could improve our understanding of the effects of DP in humans. DP concentrations in 48 hair samples from male and female students and in 30 indoor dust samples from dormitories and classrooms used by the students were determined. The objective was to determine the difference of DP concentration between indoor dust and hair, and to explore the effect of DP in dust on DP in hair of male and female students. The mean DP concentration was significantly higher in male dormitory dust than female dormitory dust, and the estimated DP dose through exposure to dust was also significantly higher for males than females. However, the mean DP concentration was significantly higher for hair from females than from males. The median DP fanti was significantly lower for hair than dust, indicating DP may be stereoselectively metabolized by humans. The median DP fanti was significantly higher for hair from females than from males, indicating DP may be metabolized differently by males and females. Human serum albumin preferred combination with anti-DP, rather than syn-DP. DP in indoor dust was not a major direct source of the DP in the hair, meaning DP in hair mainly came from within the body. There may be significant differences in DP, particularly anti-DP, metabolism in males and females.

Determination of chromium(VI) by surface plasmon field-enhanced resonance light scattering.

A surface plasmon-enhanced resonance light scattering method has been developed. The method features strong light scattering but very weak background, and after incorporating with selective sample extraction and ion-association complexation using rhodamine B and KI as reactants, it could selectively determine Cr(VI) in both of standard and real samples, reaching a limit of detection down to 20 nM which is about 40-fold as sensitive as flame atomic absorption spectrometry and 140-fold as sensitive as fluorescent spectroscopy. Its linear working range was found in between 40 and 320 nM, with a relative standard deviation of peak height at <3% (n = 5) and recovery between 94.8-104.9%. In theory, the method is applicable to the analysis of all substances able to produce or destroy I2.