TLC-Based Fingerprinting Analysis of the Geographical Variation of Melastoma malabathricum in Inland and Archipelago Regions: A Rapid and Easy-to-Use Tool for Field Metabolomics Studies.

Melastoma malabathricum is an Indo-Pacific herb that has been used traditionally to treat numerous ailments such as wounds, dysentery, diarrhea, toothache, and diabetes. The objective of this study was to evaluate the variability of the metabolic profiles of M. malabathricum across its geographic distribution. By employing thin layer chromatography (TLC), specimens collected from six terrestrial and archipelago regions of Indonesia were analyzed by densitometry for metabolomic fingerprinting analysis combined with chemometric tools: principal component analysis (PCA) and hierarchical cluster analysis (HCA). Two PCAs were identified as PC1 and PC2 with 41.90% and 20.36%, respectively. Our results indicate the importance of considering geographic distribution during field-collection efforts since they demonstrate regional metabolic variation in secondary metabolites of M. malabathricum, as illustrated by TLC and their biological activities.

Evaluation of the efficacy and toxicity of massoia oil nanoemulsion.

In order to enhance essential oil's stability and water insolubility, Massoia aromatica oil nanoemulsion was formulated and tested on the planktonic growth and biofilm formation of Pseudomonas aeruginosa, Staphylococcus aureus and Candida albicans; macrophage phagocytosis and on Vero cells viability. Oil in water nanoemulsion formula was optimized by using several solvents and co-solvents composition. The stability test of the formula was conducted by using a six cycle's freeze-thaw technique. Particle size and morphology were analyzed using a particle size analyzer and transmission electron microscopy. Microbial growth, biofilm formation inhibition, and cytotoxicity assays were performed on the optimized formula by using micro dilution methods. Mice macrophage phagocytosis activities against latex and C. albicans in the presence of samples were evaluated. Massoia nanoemulsion was obtained as a transparent yellowish emulsion having 99.6-99.9% of transmittance; physically and chemically stable; showed stronger antibacterial and antibiofilm on P. aeruginosa and S. aureus, moderate to C. albicans; no significant different on phagocytic activities. The IC50 of massoia oil nanoemulsion and massoia oil towards Vero cells were 35.9µg/mL and 107.5µg/mL respectively. Massoia oil nanoemulsion can protect the stability and decreases the hydrophobicity of the oil, conserve the antimicrobial and immunomodulatory activities, but increases its cytotoxicity.

Hydnophytum formicarum Jack ethanol extract modulates quorum sensing-controlled pathogenicity in Pseudomonas aeruginosa.

The discovery of new mechanism to control microbial pathogenicity by quorum sensing modulation has generated the search for quorum sensing inhibitor from natural resources. The objective of this research was to evaluate the ability of Hydnophytum formicarum Jack (Rubiaceae) ethanol extract to antagonize cell-to cell communication. Pulverized H. formicarum tuber was macerated in ethyl alcohol 96% and evaporated to yield ethanol extract. A dillution technique using Luria-Bertani (LB) medium was used to observe the capability of the extract to reduce the violacein production in Chromobacterium violaceum. Samples in two-fold dilution were prepared to obtain 2 - 0.0625 mg/mL concentration. The effects on swimming, swarming and twitching motility as well as the formation of biofilm towards Pseudomonas aeruginosa PAO1 were recorded over control. All experiments were done in triplicate. The architecture of Ps. aeruginosa biofilm treated with samples was examined by CLSM (Confocal Laser Scanning Microscopy) . Our results suggested that the ethanol extract of H. formicarum caused violacein production inhibition. Furthermore, inhibition of Ps. aeruginosa motility and biofilm formation were recorded to be significant over control in a concentration dependent manner. H. formicarum serves as a potential source for new QS-based antibacterial drugs towards Ps. aeruginosa.

Potency of Massoia Bark in Combating Immunosuppressed-related Infection.

BACKGROUND: As part of our search for new potential natural resources to eradicate infection, we have revealed the prominent potency of massoia bark (Massoia aromatica Becc, Lauraceae) in combating immunosuppressed-related infection. MATERIALS AND METHODS: The extract was prepared by macerating the pulverized dried bark in ethanol 95%, followed by solvent evaporation. The oil was extracted from the dried bark by steam-hydrodistillation of which preparative thin-layer chromatography was performed on the oil to isolate the active constituent, C-10 massoia lactone (ML). Anti-biofilm assay against Candida albicans was conducted on polystyrene 96 wells microtiter plates, followed by a confocal laser scanning microscope observation to get three-dimensional profiles of the affected biofilms. Effects on the hyphae development inoculated on RPMI-1640 agar plates were observed for 7 days. Influences of samples on mice macrophage phagocytosis were examined by an in vitro technique. Samples concentration tested were in the range of 2.0-0.0625 mg/mL and done in triplicate. RESULTS: Massoia bark extracts (oil and solid phase) and ML exhibited promising activities as anti-biofilm against C. albicans at IC50 0.074% v/v, 271 µg/mL and 0.026 µg/mL, respectively. The ML did not inhibit the hyphae development at the concentration tested; however, the extracts showed inhibition at 62.5 µg/mL. Macrophage phagocytosis stimulation was correlated to the ML content. CONCLUSION: Massoia bark is potential to be developed as anti-infective in immunosuppressed condition of which the C10 ML (C10H16O2) plays a major role in exerting activity. SUMMARY: Massoia bark extracts (oily and solid phase) and C-10 Massoia lactone exhibited promising activities as antibiofilm against Candida albicans at IC50 are 0.074 %v/v, 271 µg/mL and 0.026 µg/mL respectively. The major constituent, C-10 Massoia lactone (C10H16O2) plays major role in exerting anticandida activity and potentially acts as an immunomodulator as well. However extracts showed inhibition of hyphae development of C. albicans which showed no correlation to the content of the Massoia lactone. Abbreviations used: GC/MS: Gas Chromatography/Mass Spectrometry, ML: Massoia Lactone, TLC: Thin Layer Chromatography, ATCC: American Type Culture Collection, RPMI: Roswell Park Memorial Institute, PBS: Phosphate Buffer Sterile, LSM: Laser scanning microscope, DMSO: Dimethyl sulfoxide, UV: Ultra violet, SDB: Sabouraud dextrose agar, MeOH: Methanol, LB: Luria Bertani, EtOAc: Ethyl acetate, CLSM: Confocal Laser Scanning Microscope, PI: Propidium iodide.