Objective: One appealing strategy to overcome and prevent resistant problem is the use of combined two or more antibacterial substances. Lawsone methyl ether (LME) is the naphthoquinone found in the leaves of Impatiens balsamina. The objective of this study is to determine the interaction of LME with some antibiotics (ampicillin, tetracycline, norfloxacin, and clotrimazole) and a natural compound, artocarpin against methicillin-resistant Staphylococcus aureus (MRSA), Candida albicans, and Trychophyton rubrum. Methods: A broth microdilution method was used to determine the minimum inhibition concentration (MIC). Synergistic effects were evaluated at their own MIC using the checkerboard method and time-kill assay. Results: LME showed moderate antibacterial activity against MRSA with MIC value of 15.6 µg/mL, and exhibited strong antifungal activities against T. rubrum and C. albicans with MIC values of 7.8 and 3.9 µg/mL, respectively. The interaction of LME with the natural compound artocarpin against MRSA produced a synergy with fractional inhibitory concentration index (FICI) value of 0.31, while the combination of LME and clotrimazole exhibited synergy against C. albicans and T. rubrum with FICI values of 0.38 and 0.24, respectively. The time-kill assays confirmed that the compounds in combination enhanced their antimicrobial activities against the resistant microorganisms with different degrees. Conclusion: LME in combination with clotrimazole exhibited synergy effect against C. albicans and T. rubrum. In combination with artocarpin, it showed synergy effect against MRSA.

An antibacterial benzoquinone, 2,6-dimethoxy-1,4-benzoquinone, isolated from Ficus foveolata stems was used as a standard marker for establishment of quantitative HPLC analysis for the stem extracts of F. foveolata . The method utilized a TSK-gel ODS-80Ts column (5 microm, 4.6 x 250 mm) with the mixture of methanol and 5% acetic acid in water (24:76, v/v) as the mobile phase at a flow rate of 1 mL/min, and quantitative detection at 289 nm. The parameters i.e. linearity, intraday and interday precision, accuracy, specificity and sensitivity of the method were evaluated for method validation. The recoveries of the method were 99.5 - 103.6% and good linearity (R2 > or = 0.9999) was obtained. A high degree of specificity, sensitivity as well as repeatability and reproducibility (RSD less than 2 and 5%, respectively) were also achieved. Chloroform was served as the most suitable solvent for extraction of 2,6-dimethoxy-1,4-benzoquinone. The optimised sample preparation and HPLC method can be practically used in the routine quality control process of F. foveolata stem extracts.
Acetic Acid ; Chloroform ; Chromatography, High Pressure Liquid* ; Ficus* ; Methanol ; Quality Control ; Sensitivity and Specificity ; Water

A reversed-phase high-performance liquid chromatographic method is described for the simultaneous determination of three antibacterial flavonoids, artocarpanone, artocarpin, and cycloartocarpin in ethyl acetate extracts from Artocarpus heterophyllus heartwoods. Separation was achieved using a TSK-gel ODS-80Tm column (5 µm, 4.6 × 150 mm) at 25℃ with a gradient elution system of methanol and water as follows: 0-8 min, 60:40; 8-27 min, 80:20; 27-35 min, 60:40, v/v, at a flow rate of 1 mL/min, and a quantitative UV detection at 285 nm. The method was validated by measuring the key parameters, including specificity, linearity, sensitivity, accuracy, repeatability and reproducibility. A high degree of specificity and sensitivity was achieved. The calibration curves for all three flavonoids showed good linearity with a coefficient of determinations (R²) of ≥ 0.9995. The recoveries of the method were from 98-104%, with good reproducibility and repeatability (RSD values of less than 2%) were also achieved. Ethyl acetate was the best solvent for extraction of these three flavonoids using the heat reflux conditions for 1 h. This optimized sample preparation and HPLC method can be practically used for a routine standardization process of the extracts from the A. heterophyllus heartwoods.
Artocarpus* ; Calibration ; Chromatography, High Pressure Liquid* ; Flavonoids* ; Hot Temperature ; Methanol ; Methods ; Sensitivity and Specificity ; Water

Pentacyclic triterpenes, mainly, asiatic acid, madecassic acid, asiaticoside, and madecassoside are the active constituents of Centella asiatica. A pentacyclic triterpene enriched C. asiatica extract (PRE) was prepared and standardized to contain a total pentacyclic triterpenes not less than 65% w/w. This work was focused on determination of antiinflammatory, antioxidant, and tyrosinase inhibitory activities of PRE and its stability. The PRE exhibited a satisfactory nitric oxide inhibitory effect, with an IC50 value of 64.6 µg/mL. In addition, the PRE inhibited tyrosinase enzyme activity with an IC50 value of 104.8 µg/mL. In contrast, the PRE possessed only weak antioxidant activity. The PRE was stable over a period of four months when stored as a dried powder but only in a well-closed container protected from light at 4 °C. An aqueous alcoholic solution of the PRE was stable at pH values of 5.8 and 7.0, but was not stable at a pH of 8.2. Preparations of the PRE in an aqueous solution should be performed in acidic or neutral conditions.
Alcoholics ; Centella* ; Humans ; Hydrogen-Ion Concentration ; Inhibitory Concentration 50 ; Monophenol Monooxygenase ; Nitric Oxide ; Pentacyclic Triterpenes

Objective: The present study aimed to evaluate the effect of a high water-soluble curcuminoids-rich extract (CRE) in a solid dispersion form (CRE-SD) using polyvinylpyrrolidone K30 on osteogenic induction of MC3T3-E1 cells. Methods: CRE was pre-purified using a microwave assisted extraction couple with a Diaion® HP-20 column chromatography. The osteoblastic cell proliferation and differentiation potentials of CRE-SD in MC3T3-E1 cells were tested by cell viability, alkaline phosphatase (ALP) activity, and Alizarin red S activity assays. The mRNA expressions of osteoblast-specific genes and underline mechanisms were assessed by a real time PCR and western blot analysis. Results: CRE-SD 50 µg/mL increased alkaline phosphatase (ALP) activity, an early differentiation marker of osteoblasts in both MC3T3-E1 cells and non-osteogenic mouse pluripotent cell line, C3H10T1/2, indicating the action of CRE-SD was not cell-type specific. Alizarin red S activity showed a significant amount of calcium deposition in cells treated with CRE-SD. CRE-SD also upregulated the mRNA expression levels of transcription factors that favor osteoblast differentiation including Bmp-2, Runx2 and Collagen 1a, in a dose dependent manner. Western blot analysis revealed that noggin attenuated CRE-SD-promoted expressions of Bmp-2 and Runx2 proteins. siRNA mediated blocking of Wnt/β-catenin signaling pathway also annulled the influence of CRE-SD, indicating Wnt/β-catenin dependent activity. Inhibition of the different signaling pathways abolished the influence of CRE-SD on ALP activity, confirming that CRE-SD induced MC3T3-E1 cells into osteoblasts through Wnt/β-catenin and BMP signaling pathway. Conclusion: These results collectively demonstrate that CRE-SD may be a potential therapeutic agent for the treatment of osteoporosis.

Objective: To evaluate the immunosuppressive effect on human phagocytes and antibacterial activity of dihydromorin and norartocarpetin isolated from Artocarpus heterophyllus heartwoods. Methods: Dihydromorin and norartocarpetin were isolated from Artocarpus heterophyllus heartwoods. A modified Boyden chamber was used to determine the chemotactic activity of human phagocyte. The respiratory burst was evaluated by chemiluminescence assay. Myeloperoxidase (MPO) activity was quantified using a colorimetric assay. The broth microdilution method was performed to assess their antibacterial activity. Results: Dihydromorin exhibited potent inhibitory effect on the chemotactic activity of polymorphonuclear neutrophils (PMNs) with an IC50 value of 5.03 μg/mL. Dihydromorin also inhibited reactive oxygen species production of whole blood cells, PMNs, and monocytes with IC50 values of 7.88, 7.59 and 7.24 μg/mL, respectively. Interestingly, dihydromorin also strongly inhibited the MPO activity of PMNs with an IC50 value of 5.24 μg/mL, which was lower than indomethacin (24.6 μg/mL). Molecular docking of dihydromorin and crystal structure of MPO showed that dihydromorin had close interaction with key amino acid residues such as Arg239 and Gln91. Antibacterial activity assay showed that only dihydromorin had a strong effect against Streptococcus pyogenes with MIC and MBC values of 15.62 and 31.25 μg/mL, respectively. Conclusions: The results suggest that dihydromorin could be developed as an anti-inflammatory and antibacterial agent.