Satar Tursynbolat,Yrysgul Bakytkarim,Jianzhi Huang,Lishi Wang
The simultaneous electrochemical determination of myricetin and rutin remains a challenge due to their indistinguishable potentials. To solve this problem, we constructed a ternary platinum nanoparticle, reduced graphene oxide, multi-walled carbon nanotubes (Pt@r-GO@MWCNTs) nanocomposite via a facile one-pot synthetic method. Under the optimized conditions, the ternary Pt@r-GO@MWCNTs nanocomposite exhibited good electrocatalytic activity toward myricetin and rutin via solid phase extraction and excellent performance for the simultaneous determination of myricetin and rutin. The oxidation peak current of myricetin was proportional to its concentrations in the range of 0.05–50 μM with a detection limit of 0.01 μM (S/N = 3). The linear range for rutin was 0.05–50 μM with a detection limit of 0.005 μM (S/N = 3). The ternary nanocomposite sensor also exhibited good reproducibility and stability, and was successfully used for the simultaneous determination of myricetin and rutin in real orange juice samples with recoveries ranging between 100.57% and 108.46%.
Lian Yu,Yao Meng,Ze-Lin Wang,Liu Cao,Chang Liu,Ming-Zhu Gao,Chun-Jian Zhao,Yu-Jie Fu
Nowadays, developed an efficient and sustainable method to extract bioactive compounds from plants biomass has gained more and more attention. As surfactant aqueous possesses an obviously advantage of highly extraction efficiency from the raw plants, it is naturally to emerge as an alternative to traditional extractant. In order to obtain the maximum yield in the shortest time, the surfactant-based microwave-assisted extraction was applied to extract five target bioactive compounds from fig ( Ficus carica L.) leaves. Under optimal conditions, the extraction yields of caffeoylmalic acid, psoralic acid-glucoside, rutin , psoralen and bergapten reached 9.72 mg/g, 5.95 mg/g, 4.77 mg/g, 15.65 mg/g and 3.49 mg/g, respectively. These results showed that the final extraction yields were much higher than those by traditional methods. The present study indicated that the surfactant (PEG8000)-based microwave-assisted extraction method was extremely sustainable and efficient for extraction of active ingredient from fig leaves.
Huang Shuai,Wang Qiang,Wang Yaosong,Ying Ruifeng,Fan Gongjian,Huang Meigui,Agyemang Mary
This study characterized the quality, composition and antioxidant activities of olive oil from four olive varieties grown in Chongqing, southwest of China. With the fruit skin turned from green to semi black, the percentage of oleic acid decreased while the percentage of linoleic acid increased. The highest concentrations of total phenolic content, total flavonoid content and total antioxidant activity were found in the Coratina olive oils, in which the lowest content of oleuropein was also observed. Significant differences of fatty acid composition at sn-2 position were observed among the varieties, with the percentage of oleic acid at sn-2 position in Picual olive oils were significantly higher than that of other varieties ( p < 0.05). In addition, the different varieties of olive oil samples were divided into three categories by principal component analysis (PCA), and the quality of Coratina olive oils were greatly affected by fruit ripening stage. With the fruit ripening, the levels of hydroxytyrosol, rutin, total phenolics, total flavonoids and antioxidant activities in Coratina olive oil all declined. This work can provide guidance for the harvesting time and processing of olives in Chongqing.
危险品化学品经营许可证（带存储）