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Background: Our previous study successfully identified that 3,3-Dimethylquercetin (DMQ) acted as a potent anticancer agent against human colon cancer cell lines RKO. Thus, this study was conducted to investigate the underlying mechanism by which DMQ displayed inhibitory activity in RKO cells. Methods: Flow cytometry was used to evaluate the effect of DMQ on the cell cycle arrest, as well as the mitochondrial membrane potential in RKO cells. DAPI staining and DNA fragmentation ladder assays were performed to assess the apoptosis inducing activity of DMQ. Furthermore, western blot analysis was conducted to examine the expression of related proteins responsible for the cell cycle arrest and apoptosis. Results: Treatment with DMQ caused a significant increase in the fraction of G2/M cells, and induced remarkable apoptosis. Furthermore, western blot analysis showed that DMQ arrested cells at G2/M checkpoint by down-regulation of cyclin B1, cdc2 and cdc25c and up-regulation of p21, and induced cell apoptosis via affecting the ratio of Bax/Bcl-2, causing loss of the mitochondrial membrane potential and enhancing the expression of cleaved caspase-9 (C-caspase-9) and cleaved caspase-3 (C-caspase-3). Conclusion: These data showed that DMQ could suppress RKO cell growth by arresting RKO cells at G2/M checkpoint and inducing mitochondria-dependent cell apoptosis. Our findings shed light on the potential use of DMQ as a chemotherapeutic agent for CRC.

A facile and palladium-free process for the electroless plating on poly(vinyl chloride) (PVC) plastic has been demonstrated. The process is based on the Cu adsorption capacity of semi-interpenetrating polymer network (semi-IPN) hydrogel chemically bonded to PVC surface via a simple and one-step approach that applying a chitosan/polyethylene glycol/glutaraldehyde system under mild stirring at room temperature. Therefore, electroless plating can be achieved in the following three steps, namely: (1) the functionalization of PVC by the semi-IPN hydrogel film (2) the adsorption and formation of the catalyst Cu0 on the PVC surface, and (3) the electroless nickel plating in plating bath. Batch adsorption experiments are conducted to determine the effects of pH, initial Cu2+ ions concentration and the dosage of crosslinking agent glutaraldehyde on copper adsorption and the surface resistance of the corresponding plated-PVC. The activated reaction progress and resulting nickel–phosphorus (Ni–P) layer were characterized by attenuated total reflection Fourier transform infrared, scanning electron microscopy, X-ray photoelectron spectroscopy, energy dispersive X-ray spectroscopy, and X-ray diffraction. The results show that the Cu nanoparticles chemisorbed on the functionalized PVC substrate, could effectively initial the subsequent electroless nickel plating; and a compact and continuous Ni–P layer with amorphous phase was successfully deposited on PVC by this process. Besides, the surface resistance of the plated-PVC as low as 0.5 Ω sq−1 showed an excellent adhesion with the PVC substrate proved by Scotch-tape test.

Research highlights ▶ 1.28 mM potassium is favourable to the growth of Houttuynia cordata Thunb. ▶ High photosynthetic rate is due to increased chlorophyll and stable chloroplast. ▶ Stomatal conductance is limited by potassium supplies. ▶ Potassium starvation and high potassium reduce water content and root growth. ▶ Potassium starvation and high potassium cause oxidative stress., Houttuynia cordata Thunb. is an edible herb with a variety of pharmacological activities, but only limited information is available about its response towards potassium supplementation. Sterile plantlets were cultured in media with different potassium levels, and parameters related to growth, foliar potassium, water and chlorophyll contents, photosynthesis, transpiration, H2O2 contents and antioxidative enzyme activities were determined after a month. Results showed that 1.28 mM potassium was the optimum for H. cordata as highest values of dry weight, shoot height, root length and number were obtained at this concentration. The optimum potassium concentration resulted in the maximum net photosynthetic rate which could be associated with the highest chlorophyll content rather than limited stomatal conductance. The supply of surplus potassium resulted in higher content of foliar potassium, but negatively correlated with the biomass. Both potassium starvation (0 mM) and high potassium (>1.28 mM) could lead to water loss through high transpiration rate and low water absorption, respectively, and resulted in H2O2 accumulation and increased activities of catalase and peroxidase, which suggested induction of oxidative stress. Moreover, H. cordata showed the minimum of H2O2 content and the maximum of superoxide dismutase activity on 1.28 mM potassium, implying its role in inducing tolerance against oxidative stress.

To develop the characteristic chromatographic profile of Sarcandra glabra by HPLC for its quality control.The HPLC analysis was performed on an Agilent Zorbax Eclipse XDB-C18 column (4. 6 mm x 250 mm, 5 microm) with column temperature at 40 degree C. The mobile phase was consisted of water containing 0. 5% formic acid and acetonitrile to methanol (1:9) in gradient mode, and the detection wavelength was set at 344 nm.A common mode of the HPLC characteristic chromatographic profile has been establised. There were 20 common peaks , seven of which were identified, and 46 samples from different habitats were classified into five groups based on principal component cluster analysis.The method was time-saving and can represent the chemical information and provide a scientific basis for quality control of S. glabra.

Houttuynia cordata is one of the most potential medicinal and edible wild herb whose resources have decreased sharply due to excessive exploitation. Besides its slow agamic propagation, problems of browning and non-dedifferentiation have prevented the application of micropropagation in H. cordata. Through 4 week pre-culture in darkness and wounding after 1 week pre-culture, the browning rate of leaf explants decreased significantly and resulted in efficient regeneration (20.64 +/- 5.94 adventitious buds per explant) on the induction medium. The protocol shall facilitate conservation and commercial cultivation of the endangered species.

Eclipta prostrata, an aromatic plant, is known in Chinese herbal medicine for the treatment of various kidney diseases. In the present study, the volatile components were isolated from the aerial parts of this plant by hydrodistillation and analysed by GC-MS. A total of 55 compounds, which were the major part (91.7%) of the volatiles, were identified by matching mass spectra with a mass spectrum library (NIST 05.L). The main components were as follows: heptadecane (14.78%), 6,10,14-trimethyl-2-pentadecanone (12.80%), n-hexadecanoic acid (8.98%), pentadecane (8.68%), eudesma-4(14),11-diene (5.86%), phytol (3.77%), octadec-9-enoic acid (3.35%), 1,2-benzenedicarboxylic acid diisooctyl ester (2.74%), (Z,Z)-9,12-octadecadienoic acid (2.36%), (Z)-7,11-dimethyl-3-methylene-1,6,10-dodecatriene (2.08%) and (Z,Z,Z)-1,5,9,9-tetramethyl-1,4,7-cycloundecatriene (2.07%). The effects of volatile components and ethanolic extract from the aerial parts of this plant on the proliferation and differentiation of primary osteoblasts were evaluated by the MTT method and measuring the activity of alkaline phosphatase (ALP activity). Both volatile components and ethanolic extract (1 microg/mL to 100 microg/mL) significantly (p < 0.01) stimulated the proliferation and increased the ALP activity of primary osteoblasts. These results propose that E. prostrata can play an important role in osteoblastic bone formation, and may possibly lead to the development of bone-forming drugs.

To promote its comprehensive utilization, the involatile constituents of Mentha haplocalyx were studied systematically.The chemical components were isolated and purified by silca gel column chromatography and recrystallization. The chemical structures were elucidated on the basis of physico-chemical properties and spectral data.Eight compounds were isolated and identified as: acacetin (I), tilianine (II), linarin (III), n-butyl-beta-D-fructopyranoside (IV), ursolic acid (V), oleanolic acid (VI), beta-sitosterol (VII), daucosterol (VIII).Compounds I approximately V were obtained from this plant for the first time.