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Artocarpin-rich extract (ARE) was prepared using a green technology and standardized to contain 49·6% w/w artocarpin, while lawsone methyl ether was prepared using a green semi-synthesis. ARE, LME and ampicillin exhibited weak anti-MRSA activity with the MICs of 31·2-62·5 µg/ml. Based on the checkerboard assay, the synergistic interaction between ARE (0·03 µg/ml) and LME (0·49 µg/ml) against four MRSA isolates were observed with the fractional inhibitory concentration index (FICI) value of 0·008, while those of ARE (1·95-7·81 µg/ml) and ampicillin (0·49 µg/ml) as well as LME (0·49-1·95 µg/ml) and ampicillin (0·49 µg/ml) were 0·016-0·257. The time kill confirmed the synergistic interactions against MRSA with different degrees. The combination of ARE and LME as well as its combinations with ampicillin altered the membrane permeability of MRSA, which led to release of the intracellular materials. In addition, each compound inhibited the biofilm formation of standard MRSA (DMST 20654) and the clinical isolate (MRSA 1096). These findings suggested that cocktails containing ARE and LME might be used to overcome problems associated with MRSA. Additionally, the results implied that combination of either ARE or LME with available conventional antibiotic agents might be effective in countering these perilous pathogens., (© 2022 The Society for Applied Microbiology.)

α-Mangostin-rich extract (AME) exhibited satisfactory inhibitory activities against all tested MRSA strains, with minimum inhibitory concentrations (MICs) of 7·8-31·25 µg ml -1 , whereas lawsone methyl ether (LME) and ampicillin revealed weak antibacterial activity with MICs of 62·5-125 µg ml -1 . However, the combination of AME and LME showed synergistic effects against all tested MRSA strains with fractional inhibitory concentration index (FICI) values of 0·008-0·009, while the combination of AME and ampicillin, as well as LME and ampicillin produced synergistic effects with FICIs of 0·016-0·257. A time-kill assay against MRSA (DMST 20654 strain) revealed a 6-log reduction in CFU per ml, which completely inhibited bacterial growth for the combinations of AME and LME, AME and ampicillin, and LME and ampicillin at a 8-h incubation, while those against MRSA (2468 strain) were at 10-h incubation. The combination of α-mangostin and LME as well as the combinations of each compound with ampicillin synergized the alteration of membrane permeability. In addition, α-mangostin, LME and ampicillin inhibited the biofilm formation of MRSA. These findings indicated that the combinations of AME and LME or each of them in combination with ampicillin had enhanced antibacterial activity against MRSA. Therefore, these compounds might be used as the antibacterial cocktails for treatment of MRSA., (© 2020 The Society for Applied Microbiology.)

Objectives: To examine the effects of chamuangone on human cancer cell proliferation, migration and apoptosis., Methods: An MTT assay was used to study the effect of chamuangone on human cervical carcinoma cell growth. An in-vitro scratch migration assay was used to investigate the activity of cell motility after chamuangone treatment. Chamuangone-induced cell apoptosis in HeLa cells was determined using the apoptotic assay kit. The inhibitory activities of chamuangone were examined by ADP-Glo™ kinase assay. The GOLD docking algorithm was used to demonstrate the mechanism against tyrosine kinase of EGFR., Key Findings: Chamuangone showed a strong inhibitory cell proliferation of HeLa cells with IC 50 values of 3.59 µm and effectively inhibited HeLa cell migration. In addition, chamuangone exhibited the apoptotic cell death induction in a time and dose-dependent manner. Finally, chamuangone also was tested for EGFR-TK inhibition activity. The IC 50 value of chamuangone was 2.85 nm, whereas the IC 50 value of gefitinib was 15.10 nm., Conclusions: The above results confirm the inhibitory effects of chamuangone on HeLa cell proliferation and cell migration. In addition, chamuangone also induces cell apoptosis in HeLa cells. These findings indicate that chamuangone is a compound that is a potential chemotherapeutic agent., (© 2019 Royal Pharmaceutical Society.)

Objectives: To investigate the effects of flavonoids isolated from Artocarpus heterophyllus. heartwood on chemotaxis, phagocytosis, reactive oxygen species (ROS) production and myeloperoxidase (MPO) activity of human phagocytes., Methods: Chemotaxis was evaluated using a modified Boyden chamber and phagocytosis was determined by flowcytometer. Respiratory burst was investigated by luminol-based chemiluminescence assay while MPO activity was determined by colorimetric assay., Key Findings: Artocarpanone and artocarpin strongly inhibited all steps of phagocytosis. Artocarpanone and artocarpin showed strong chemotactic activity with IC 50 values of 6.96 and 6.10 μm, respectively, which were lower than that of ibuprofen (7.37 μm). Artocarpanone was the most potent compound in inhibiting ROS production of polymorphonuclear leucocytes and monocytes with IC 50 values comparable to those of aspirin. Artocarpin at 100 μg/ml inhibited phagocytosis of opsonized bacteria (28.3%). It also strongly inhibited MPO release with an IC 50 value (23.3 μm) lower than that of indomethacin (69 μm). Structure-activity analysis indicated that the number of hydroxyl group, the presence of prenyl group and variation of C-2 and C-3 bonds might contribute towards their phagocytosis., Conclusions: Artocarpanone and artocarpin were able to suppress strongly the phagocytosis of human phagocytes at different steps and have potential to be developed into potent anti-inflammatory agents., (© 2018 Royal Pharmaceutical Society.)

A reversed-phase high-performance liquid chromatographic method is described for the simultaneous determination of rhinacanthin-C, rhinacanthin-D, and rhinacanthin-N in Rhinacanthus nasutus leaves. The method involved the use of a TSK-gel ODS-80Ts column (5 microm, 4.6 x 150 mm i.d.) with the mixture of methanol and 5% aqueous acetic acid (80:20, v/v) as the mobile phase. The parameters of linearity, repeatability, accuracy, and specificity of the method were evaluated. The recovery of the method was 94.3-100.9%, and good linearity (r(2) > or = 0.9999) was obtained for all rhinacanthins. A high degree of specificity as well as repeatability and reproducibility (relative standard deviation values less than 5%) were also achieved. The limit of detection and quantification of all rhinacanthins were 0.75 and 3.0 microg/mL, respectively. The solvents for extraction of rhinacanthins from R. nasutus leaves were examined in order to obtain the leaf extract with high rhinacanthin content. It was found that ethyl acetate was an appropriate solvent for rhinacanthin extraction. Fractionation of the ethyl acetate extract using a basic anion exchange resin (Amberlite IRA-67) eluted with 10% acetic acid in methanol afforded a rhinacanthin-rich extract (HRn). The total content of rhinacanthins was increased from 37.4% w/w to 77.5% w/w. The antifungal activities of HRn against Trichophyton rubrum, T. mentagrophytes, and Microsporum gypseum were also improved.

A reversed-phase high-performance liquid chromatographic method is described for the simultaneous determination of four anthraquinones: rhein, aloe-emodin, emodin, and chrysophanol in Senna alata leaves. The method involves the use of a TSK-gel ODS-80Tm column (5 microm, 4.6 x 150 mm) at 25 degrees C with the mixture of methanol and 2% aqueous acetic acid (70:30, v/v) as the mobile phase and detection at 254 nm. The parameters of linearity, precision, accuracy, and specificity of the method were evaluated. The recovery of the method is 100.3-100.5%, and linearity (r(2) > 0.9998) was obtained for all anthraquinones. A high degree of specificity as well as repeatability and reproducibility (relative standard deviation values less than 5%) were also achieved. The solvent for extraction of anthraquinones from S. alata leaves was examined in order to increase the anthraquinone content of the leaf extract. It was found that a solution of 5% hydrochloric acid (v/v), 5% ferric chloride (w/v), and 15% water in methanol (v/v) was capable of increasing the anthraquinone content in the leaf extract up to 1.67% (w/w).