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Antioxidant activity constituents of Lonicera japonica leave
Abstract
A wavelength conversion method was established to determine chlorogenic acid, luteolin and luteoloside in Lonicera japonica leaves. The content of chlorogenic acid in aqueous phase was 2.05%, while the content of luteolin and luteoloside in EA phase were 1.12% and 0.57%, respectively. The antioxidative activity of effective components in Lonicera japonica leaves was evaluated by DPPH·, FRAP and ORAC with Vc as reference substance. The results showed that crude extraction, crude fraction, chlorogenic acid, luteolin and luteoloside in Lonicera japonica leaves all had great antioxidative activity. The strongest antioxidant capacity substance was luteolin, its IC50 value, reducing capacity and ORAC value were 0.01764 mg/mL, 1751.8±13.9 mmol/L and 23817.44 μmol Trolox/g, respectively. The crude fraction eluted by 30% ethanol also showed high antioxidative acitivity, its IC50 value, reduction capability and ORAC value were 0.02548 mg/mL, 933.8±11.6 mmol/L, and 10557.97 μmol Trolox/g, respectively. The antioxidative activity of each constituent increased with the increase of concentration and purity of the antioxidant. Therefore, there is broad development and utilization prospect of the antioxidant activity constituents of Lonicera Japonica leaves as a new type efficient non-toxic antioxidant.
... [18][19][20][21][22] It was also reported that the extracts of leaves and stems have in vitro antimicrobial, antifungal, and antioxidant effects. [22][23][24] Accordingly, leaves and stems could be applied in the food or pharmaceutical industries as well. Most reports about leaves and stems focus on their chemical components, while only in vitro research was done on their beneficial properties. ...
... Among these identified compounds, 12 compounds (1,2,4,6,9,11,12,15,18,22,23,27) were hydroxycinnamic acids, seven compounds (19,20,21,24,25,28,30) were flavonoids, and the rest were iridoids. Most of the characteristic bioactive components in FLJ including chlorogenic acid, 3,4-dicaffeoylquinic acid, and 3,5-dicaffeoylquinic acid were also detected in LLJ and SLJ. ...
BACKGROUND
Lonicera japonica Thunb is a common herb in East Asia. The flower buds are usually regarded as the traditional medicinal part, while leaves and stems are considered less valuable and receive little attention. This study compared the chemical constituents and anti‐inflammatory effects of the different tissues in L. japonica Thunb for the first time.
RESULTS
Thirty compounds were identified by ultra‐performance liquid chromatography‐photodiode detector‐quadrupole / time of flight‐mass spectrometry (UPLC‐PDA‐Q/TOF‐MS/MS) analysis. Hydroxycinnamic acids, flavonoids, and iridoids were identified as the major components. The flower buds (FLJ), leaves (LLJ), and stems (SLJ) of L. japonica Thunb showed strong similarities in chemical components. The LLJ contained higher levels of hydroxycinnamic acids and flavonoids than the FLJ and SLJ.
Furthermore, FLJ, LLJ, and SLJ exhibited potent anti‐inflammatory activity in croton oil‐induced ear edema and carrageenan‐induced paw edema assays in mice. Moreover, FLJ, LLJ, and SLJ showed a cytoprotective effect on lipopolysaccharide‐ (LPS‐) stimulated RAW 264.7 macrophages. Lipopolysaccharide‐induced increases in nitric oxide (NO), tumor necrosis factor‐α (TNF‐α), interleukin‐1β (IL‐1β), and interleukin‐6 (IL‐6) were suppressed by treatments of FLJ, LLJ, and SLJ, respectively. The LLJ possessed a stronger anti‐inflammatory effect than the FLJ.
CONCLUSION
Leaves and stems of L. japonica Thunb have chemical components and anti‐inflammatory properties similar to flower buds, and may become alternative or supplementary sources of flower buds. © 2019 Society of Chemical Industry
The black bean was used as raw materials to study the main components and antioxidant activity of traditional fermented soybean and pure fermentation. The results showed that, after fermentation, its protein and reducing sugars had 1.9%~4.2% and 1.5%~2.1% decreased respectively. The contents of acidity, peptide, fat and melanoidin increased 1.0%~1.3%, 1.5%~1.6%, 6.2%~7.5% and 1.7%~2.0%, respectively. The antioxidant activity were investigated by DPPH· (2, 2-diphenyl-1-picrylhydrazyl) method, salicylic acid method and deoxidization Fe3+ method and compared with that of Vitamin C. The results showed that the antioxidant activity of the traditional fermented soybean was better than black beans. The pure fermented soybean showed the lowest antioxidant effect.
Due to the excellent mechanical, thermal and electrical properties, graphene/polymer composite is expected to have a variety of applications in analytical chemistry. In this study, a new poly(ethylene glycol dimethacrylate)/graphene composite was prepared by in situ polymerization. The new composite was used for the first time as the extraction coating of stir rod sorptive extraction for the preconcentration of polycyclic aromatic hydrocarbons (PAHs) from water samples. Because of the high specific surface area and π–π electrostatic stacking properties of graphene, the graphene-polymer composite showed higher extraction efficiencies towards most target PAHs from water samples than the neat polymer. Under the optimal conditions, a method for the determination of PAHs in water samples was proposed based on the combination of stir rod sorptive extraction (SRSE) and gas chromatography-mass spectrometry (GC-MS). The limit of detection (LODs) of the developed method for 16 PAHs ranged from 0.005 to 0.429 ng mL−1, depending on the compound. Good reproducibility of method was obtained as intra- and inter-day precisions, the relative standard deviations (RSDs) were less than 12.5% and 12.6%, respectively.
Natural products have been the most productive source of leads for new drugs, but they are currently out of fashion with the pharmaceutical industry. New approaches to sourcing novel compounds from untapped areas of biodiversity coupled with the technical advances in analytical techniques (such as microcoil NMR and linked LC-MS-NMR) have removed many of the difficulties in using natural products in screening campaigns. As the 'chemical space' occupied by natural products is both more varied and more drug-like than that of combinatorial chemical collections, synthetic and biosynthetic methods are being developed to produce screening libraries of natural product-like compounds. A renaissance of drug discovery inspired by natural products can be predicted.