Inhibitory potential against methicillin-resistant staphylococcus aureus (MRSA) of Dolichandrone spathacea, a mangrove tree species of Malaysia

In this study, methanol extracts from the leaf and stem of Dolichandrone spathacea (L.f) K. Schum., a lesser-known local mangrove tree species, was evaluated using disc diffusion and minimum inhibitory concentration (MIC) value determination assays against six strains of local MRSA clinical isolates and one ATCC MRSA reference strain. The stem extract exhibited a higher zone of inhibition as compared with the leaf extract against the tested isolates. Further qualitative evaluation of the stem extract showed MIC values between 1.25 to 1.88 mg/ml against three selected MRSA clinical isolates. Phytochemical screening revealed that the triterpene and saponin compounds might be responsible for the better inhibitory activity from the stem extract as compared to the leaf extract. This study is the first report of the phytochemical screening and the inhibitory activity of D. spathacea leaves and stems methanolic extracts against MRSA clinical isolates.Colegio de Farmacéuticos de la Provincia de Buenos Aire

Inhibitory potential against methicillin-resistant staphylococcus aureus (MRSA) of Dolichandrone spathacea, a mangrove tree species of Malaysia

In this study, methanol extracts from the leaf and stem of Dolichandrone spathacea (L.f) K. Schum., a lesser-known local mangrove tree species, was evaluated using disc diffusion and minimum inhibitory concentration (MIC) value determination assays against six strains of local MRSA clinical isolates and one ATCC MRSA reference strain. The stem extract exhibited a higher zone of inhibition as compared with the leaf extract against the tested isolates. Further qualitative evaluation of the stem extract showed MIC values between 1.25 to 1.88 mg/ml against three selected MRSA clinical isolates. Phytochemical screening revealed that the triterpene and saponin compounds might be responsible for the better inhibitory activity from the stem extract as compared to the leaf extract. This study is the first report of the phytochemical screening and the inhibitory activity of D. spathacea leaves and stems methanolic extracts against MRSA clinical isolates.Colegio de Farmacéuticos de la Provincia de Buenos Aire

Inhibitory potential against methicillin-resistant staphylococcus aureus (MRSA) of Dolichandrone spathacea, a mangrove tree species of Malaysia

In this study, methanol extracts from the leaf and stem of Dolichandrone spathacea (L.f) K. Schum., a lesser-known local mangrove tree species, was evaluated using disc diffusion and minimum inhibitory concentration (MIC) value determination assays against six strains of local MRSA clinical isolates and one ATCC MRSA reference strain. The stem extract exhibited a higher zone of inhibition as compared with the leaf extract against the tested isolates. Further qualitative evaluation of the stem extract showed MIC values between 1.25 to 1.88 mg/ml against three selected MRSA clinical isolates. Phytochemical screening revealed that the triterpene and saponin compounds might be responsible for the better inhibitory activity from the stem extract as compared to the leaf extract. This study is the first report of the phytochemical screening and the inhibitory activity of D. spathacea leaves and stems methanolic extracts against MRSA clinical isolates.Colegio de Farmacéuticos de la Provincia de Buenos Aire

Inhibitory and resistance-modifying potential of plant-based alkaloids against methicillin-resistant staphylococcus aureus (MRSA)

Increased prevalence of methicillin-resistant Staphylococcus aureus (MRSA) has become a major threat to the health sector worldwide due to their virulence, limited therapeutic options and their distribution in both hospital and community settings. Discovery and development of new anti-MRSA agents as alternatives to the very few antibiotics left in the armamentarium are, thus, urgently required. Recently, an efflux mechanism in MRSA has been identified as one of the main contributors of resistance towards various structurally unrelated antibiotics. The potential of reserpine (a phytoalkaloid) as efflux pump inhibitor (EPI) against various microbes remains limited as the concentration needed for inhibition is toxic to humans. This study therefore aimed to evaluate 13 alkaloid compounds as potential inhibitory agents and/or potential EPIs against a panel of three MRSA isolates which not only differ in their susceptibility to vancomycin (amongst the last drugs available to treat serious MRSA infection), but also exhibited active efflux activity. Results indicated berberine's moderate inhibitiory activity against two MRSA isolates scoring a minimum inhibitory concentration (MIC) value of 125 microg/ml. Notable efflux inhibitory activity (ranging from two- to eightfold Ethidium Bromide MIC reduction) meanwhile was detected from quinine, piperine and harmaline using reserpine as the positive control. Findings from this study support the opinion that a vast number of potential phytocompounds with pharmacological potential await discovery. Therapeutic application of these compounds, however, warrants further investigation to ascertain their pharmacodynamics and safety aspects

Chemical compositions and antimicrobial activity of twig essential oils from three Xylopia (Annonaceae) species

The chemical composition of twig essential oils of Xylopia malayana, Xylopia elliptica and Xylopia fusca were analyzed using GC and GCMS. Both X. malayana (12.9%) and X. fusca (11.8%) twig oils contained spathulenol as the major constituent while X. elliptica twig oil was found to be rich in terpinen-4-ol (11.9%). The antimicrobial activities of the essential oils were evaluated against six gram positive bacteria, two gram negative bacteria and yeast by using the broth microdilution method. The twig oil of X. elliptica at a concentration ranging from 156 to 625 μg/ml was found to be active against all bacterial and yeast strains tested. Both X. malayana and X. fusca twig oils demonstrated weak activity toward all microorganisms tested with the MIC value of 5000 μg/ml. Gram negative bacteria’s, Pseudomonas aeruginosa and Escherichia coli seemed to be resistant to the essential oils tested. α-Pinene showed moderate to strong inhibitory effect against all the microorganism strains tested with the MIC value ranging from 325 to 2500 μg/ml, as compared to the other standard compounds which showed weak inhibitory even at the highest concentrations used. This finding demonstrated that the twig oil of X.elliptica possesses antimicrobial activity which may be useful and potential ingredient in the production of health care products.Key words: Xylopia twigs, essential oils, GC & GCMS analysis, antimicrobial activity

Antimicrobial Activities of curcumin Extracted from Selected Zingiberaceae species as potential halal active pharmaceutical ingredient

The ginger family (Zingiberaceae) includes plants with a distinct smell and taste that are commonly used as spices in the kitchen, but also in a variety of industries (pharmaceutical, medical, and cosmetic) due to their demonstrated biological activity. This study describes the antibacterial activity of curcumin extracts from selected species of Zingiberaceae family namely “temu emas” (Curcuma zeodoria). “temu kunci” (Curcuma manga), “temu pauh” (Curcuma amada), “lempoyang” (Zingiber zerumbit) and “cekur” (Kaempferia galangal). Extracts of these compounds were studied on Staphylococcus aureus (ATCC 25923), Escherichia coli (ATCC 35218), Salmonella typhimurium (ATCC 14028), Candida albicans (ATCC 10231) and Aspergilus brasiliensis (ATCC 16404). Turbidity is taken as an indication of growth, thus the lowest concentration, which remains clear after macroscopic evaluation is taken as the minimum inhibitory concentration (MIC). In conclusion, amongst the studied members of Zingiberaceae, temu emas curcumin natural pigment extracts showed the best antibacterial activities against E. coli ATCC 35218 (2 µg / µL), S. typhimurium ATCC 14028 (2 µg / µL), C. albicans ATCC 10231 (2 µg / µL), A. brasiliensis ATCC 16404 (2 µg / µL) and S. aureus ATCC 25923 (3 µg / µL). The outcome of this research will contributing towards new natural carotenoid pigment sources as potential active pharmaceutical ingredients which can be beneficial to halal health-promoting products industry

Diversity of endophytic fungi isolated from different plant parts of Acacia mangium, and antagonistic activity against Ceratocystis fimbriata, a causal agent of Ceratocystis wilt disease of A. mangium in Malaysia

Acacia mangium is an important wood for commercial products especially pulp and medium-density fibreboard. However, it is susceptible to Ceratocystis fimbriata infection, leading to Ceratocystis wilt. Therefore, the present work aimed to (i) establish the diversity of endophytic fungi in different plant parts of A. mangium,and (ii) evaluate the antifungal potentials of the isolated and identified endophytic fungi against C. fimbriata. Endophytic fungal identification was conducted by PCR amplification and sequencing of the internal transcribed spacer 1 (ITS1) and ITS4 regions of nuclear ribosomal DNA. A total of 66 endophytic fungi were successfully isolated from different parts of A. mangium; leaf (21), stem (13), petiole (12), root (9), flower (6), and fruit (5). The endophytic fungal isolates belonged to Ascomycota (95.5%) and Zygomycota (4.5%). For Ascomycota 13 genera were identified: Trichoderma (28.6%), Nigrospora (28.6%), Pestalotiopsis (12.7%), Lasiodiplodia (9.5%), Aspergillus (6.3%), Sordariomycetes (3%), and Neopestalotiopsis, Pseudopestalotiopsis, Eutiarosporella, Curvularia, Fusarium, Penicillium, and Hypoxylon each with a single isolate. For Zygomycota, only Blakeslea sp. (5%) was isolated. Against C. fimbriata, Trichoderma koningiopsis (AC 1S) from stem, Nigrospora oryzae (AC 7L) from leaf, Nigrospora sphaerica (AC 3F) from the flower, Lasiodiplodia sp. (AC 2 U) from fruit, Nigrospora sphaerica (AC 4P) from petiole, and Trichoderma sp. (AC 9R) from root exhibited strong inhibition for C. fimbriata between 58.33 to 69.23%. Thus, it can be concluded that certain endophytic fungi of A. mangium have the potential to be harnessed as anti-Ceratocystis agent in future biotechnological applications

Efflux genes and active efflux activity detection in of methicillin-resistant Staphylococcus aureus (MRSA).

Efflux-mediated resistance has been recognized as an important contributor of antibiotic resistance in bacteria, especially in methicillin-resistant Staphylococcus aureus (MRSA) isolates. This study was carried out to detect and analyze efflux genes (norA and mdeA) and active efflux activity in a collection of Malaysian MRSA and methicillin-sensitive S. aureus (MSSA) clinical isolates. Nineteen isolates including three ATCC S. aureus reference strains were subjected to PCR detection and DNA sequence analysis for norA and mdeA and active efflux detection using modified minimum inhibitory concentration (MIC) assay. From the 19 isolates, 18 isolates harboured the mdeA gene while 16 isolates contained norA gene. DNA sequence analysis reveals 98–100% correlation between the PCR product and the published DNA sequences in GenBank. In addition, 16 isolates exhibited active efflux activity using the ethidium bromide (EtBr)- reserpine combination MIC assay. To our knowledge, this is the first report on the detection of efflux genes and active efflux activity amongst Malaysian clinical isolates of MRSA/MSSA. Detection of active efflux activity may explain the previous report on efflux-mediated drug resistance profile amongst the local clinical isolates

Cytotoxic Activity of MFM 501, a Novel Codonopsinine Derivative, against Methicillin-Resistant Staphylococcus aureus Clinical Isolates

28 new pyrrolidine types of compounds as analogues for natural polyhydroxy alkaloids of codonopsinine were evaluated for their anti-MRSA activity using MIC and MBC value determination assay against a panel of S. aureus isolates. One pyrrolidine compound, MFM 501, exhibited good inhibitory activity with MIC value of 15.6 to 31.3 g/mL against 55 S. aureus isolates (43 MRSA and 12 MSSA isolates). The active compound also displayed MBC values between 250 and 500 g/mL against 58 S. aureus isolates (45 MRSA and 13 MSSA isolates) implying that MFM 501 has a bacteriostatic rather than bactericidal effect against both MRSA and MSSA isolates. In addition, MFM 501 showed no apparent cytotoxicity activity towards three normal cell lines (WRL-68, Vero, and 3T3) with IC 50 values of >625 g/mL. Selectivity index (SI) of MFM 501 gave a value of >10 suggesting that MFM 501 is significant and suitable for further in vivo investigations. These results suggested that synthetically derived intermediate compounds based on natural products may play an important role in the discovery of new anti-infective agents against MRSA

In Vitro Inhibitory and Cytotoxic Activity of MFM 501, a Novel Codonopsinine Derivative, against Methicillin-Resistant Staphylococcus aureus Clinical Isolates

28 new pyrrolidine types of compounds as analogues for natural polyhydroxy alkaloids of codonopsinine were evaluated for their anti-MRSA activity using MIC and MBC value determination assay against a panel of S. aureus isolates. One pyrrolidine compound, MFM 501, exhibited good inhibitory activity with MIC value of 15.6 to 31.3 μg/mL against 55 S. aureus isolates (43 MRSA and 12 MSSA isolates). The active compound also displayed MBC values between 250 and 500 μg/mL against 58 S. aureus isolates (45 MRSA and 13 MSSA isolates) implying that MFM 501 has a bacteriostatic rather than bactericidal effect against both MRSA and MSSA isolates. In addition, MFM 501 showed no apparent cytotoxicity activity towards three normal cell lines (WRL-68, Vero, and 3T3) with IC50 values of >625 µg/mL. Selectivity index (SI) of MFM 501 gave a value of >10 suggesting that MFM 501 is significant and suitable for further in vivo investigations. These results suggested that synthetically derived intermediate compounds based on natural products may play an important role in the discovery of new anti-infective agents against MRSA