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Propolis is a natural substance produced by the bees to protect their hive. The present work reports the utilization of chemical profiling and fingerprinting combined with multivariate analysis for discrimination of the geographical origin of Malaysian stingless bee propolis. High Performance Thin Layer Chromatography (HPTLC) has been performed to profile the chemical composition of Geniotrigona thoracica propolis from different localities in East Coast of Peninsular Malaysia namely Besut, Terengganu (BST), Dungun, Terengganu (DGN), Lundang, Kelantan (LDG), Tanah Merah, Kelantan (TM) and Gua Musang, Kelantan (GM). The obtained HPTLC profiles showed the presence of flavonoids, phenolics and terpenoids in propolis. The chemical fingerprinting was obtained through Fourier Transform Infrared (FTIR) spectroscopy. Chemometric analysis on FTIR dataset using principal component analysis (PCA) and hierarchical cluster analysis (HCA) have classified the propolis into three major groups according to their sampling locations. Chemical fingerprinting analysis on the functional group via FTIR and chemometric revealed that the locations of propolis have direct correlation with the chemical composition, thus affecting the biological activities of propolis. Both chemical marker and chemical fingerprinting analysis are important tools in propolis standardization.

Euphorbiaceae plants had been traditionally used in healing various diseases. This study was designed to determine the secondary metabolites that exist in Malaysian Euphorbia milii (Euphorbiaceae) and it’s potential in antioxidant activities. Dried leaves and flowers of E. milii were extracted using hexane, ethyl acetate, and methanol. The qualitative and quantitative phytochemical analysis was performed toward the crude extracts. The outcomes showed that alkaloids, flavonoids, quinones, carbohydrates, and reducing sugar were mainly present in all of the samples extracted by the three solvents. For quantitative analysis, methanolic leaves extract contained the highest amount of flavonoids, given as 0.0867 ± 0.005 mg QE/g of the sample compared to other extracts. Meanwhile, the determination of antioxidant activities of each extract showed that methanol leaves extract consists of the highest antioxidant activity due to the presence of phytochemical compounds. This significant data provides preliminary findings that may lead to further development as a potential source of herbal medicine.

International audience; A phytochemical investigation of the methanolic extract of Endiandra kingiana (bark) led to the isolation of four major compounds which are kingianic acid A (1), tsangibeilin B (2), kingianin A (3) and kingianin F (4). The structures were determined by 1D- and 2D-NMR analysis in combination with HRMS experiments. The compounds were screened for their in vitro α-glucosidase inhibition activity. Among them, compounds 3-4 showed potent α-glucosidase inhibition activity with IC50 value at 11.9 ± 2.0 µM and 19.7 ± 1.5 µM, respectively. The molecular docking study found that both compounds were bound into the active site of the N-terminal of MGAM, and thus agreed with the in vitro α-glucosidase enzyme inhibition activity results.

A phytochemical investigation of the stem barks of the Malaysian Croton oblongus Burm.f. (Syn. Croton laevifolius Blume) (Euphorbiaceae) yielded seven previously undescribed ent-neo-clerodane diterpenoids, laevifins A - G (1, 2, 4-8) and the known crovatin (3). Structures were established by a combination of spectroscopic methods including HRESIMS, NMR spectroscopy and X-ray crystallography. The absolute configuration of crovatin and laevifins A-G was established by comparison of experimental ECD and theoretical TDDFT ECD calculated spectra. This is the first report on the occurrence of the sesquiterpenoid cryptomeridiol in a Croton species. In vitro cytotoxicity assays on laevifins A (1), B (2) and G (8) showed moderate activities against the MCF-7 cancer cell line (IC50 102, 115 and 106 μM, respectively) while β-amyrin and acetyl aleuritolic acid showed good anti-inflammatory activity on the LPS-induced NF-κB translocation inhibition in RAW 264.7 cells assay with IC50 values of 23.5 and 35.4 μg/mL, respectively.

Ethnopharmacological relevance The rhizome of Alpinia conchigerahas been used as a condiment in the northern states of Peninsular Malaysia and occasionally in folk medicine in the east coast to treat fungal infections. In some states of Peninsular Malaysia, the rhizomes are consumed as a post-partum medicine and the young shoots are prepared into a vegetable dish. This study aimed to investigate the chemical constituents of the pseudostems and rhizomes of Malaysian Alpinia conchigera and to evaluate the antimicrobial activity of the dichloromethane (DCM) extracts of the pseudostems, rhizomes and the isolated compounds against three selected fungi and five strains of Staphylococcus aureus. Materials and methods The dried and ground pseudostems (0.8 kg) and rhizomes (1.0 kg) were successively extracted in Soxhlet extractor using n-hexane, dichloromethane (DCM) and methanol. The n-hexane and DCM extracts of the pseudostem and rhizome were subjected to isolation and purification using column chromatography on silica gel using a stepwise gradient system (n-hexane to methanol). Briefly, a serial two fold dilutions of the test materials dissolved in DMSO were prepared prior to addition of 100 μl overnight microbial suspension (108 cfu/ml) followed by incubation at 37 °C (bacteria) or 26 °C (dermatophytes and candida) for 24 h. The highest concentration of DMSO remaining after dilution (5%, v/v) caused no inhibition to bacterial/candida/dermatophytes’ growth. Antibiotic cycloheximide was used as reference for anticandidal and antidermatophyte comparison while oxacilin was used as reference for antibacterial testing. DMSO served as negative control. Turbidity was taken as indication of growth, thus the lowest concentration which remains clear after macroscopic evaluation was taken as the minimum inhibitory concentration (MIC). Results The isolation of n-hexane and DCM extracts of the rhizomes and pseudostems of Alpinia conchigera via column chromatography yielded two triterpenes isolated as a mixture of stigmasterol and β-sitosterol: caryophyllene oxide, chavicol acetate 1, p-hydroxy cinnamaldehyde 2, 1′S-1′-acetoxychavicol acetate 3, trans-p-coumaryl diacetate 4, 1′S-1′-acetoxyeugenol acetate 5, 1′-hydroxychavicol acetate 6, p-hydroxycinnamyl acetate 7 and 4-hydroxybenzaldehyde. The DCM extract of the rhizome of Alpinia conchigera indicated potent antifungal activity against Candida albicans, Microsporum canis and Trycophyton rubrum with MIC values of 625 μg/ml, 156 μg/ml and 156 μg/ml, respectively. It also showed significant inhibitory activity with MIC values between 17.88 and 35.75 μg/ml against the mutant Staphylococci isolates MSSA, MRSA and Sa7. Amongst the isolated compounds, the lowest inhibition observed were of 1′S-1′-acetoxyeugenol against the dermatophytes (MIC 313 μg/ml) followed by trans-p-coumaryl diacetate against both dermatophytes and candida (MIC 625 μg/ml). The compound p-hydroxycinnamyl acetate strongly inhibited Staphylococcus aureus strain VISA (MIC 39 μg/ml) followed by trans-p-coumaryl diacetate and 1′-hydroxychavicol acetate with MIC value of 156 μg/ml. Conclusion In conclusion, the observed antibacterial, anticandidal and antidermatophyte activity of the extracts and compounds obtained from the rhizome confirm the traditional use of Alpinia cochigera rhizome in the treatment of skin infection.

Medicinal plants containing active natural compounds have been used as an alternative treatment for cancer patients in many parts of the world especially in Asia (Itharat et al. 2004). In this report, we describe the cytotoxic and apoptotic properties of 1'S-1'-acetoxyeugenol acetate (AEA), an analogue of 1'S-1'-acetoxychavicol acetate (ACA), isolated from the Malaysian ethno-medicinal plant Alpinia conchigera Griff (Zingiberaceae) on human breast cancer cells. Data from MTT cell viability assays indicated that AEA induced both time- and dose-dependent cytotoxicity with an IC(50) value of 14.0 μM within 36 h of treatment on MCF-7 cells, but not in HMEC normal control cells. Both annexin V-FITC/PI flow cytometric analysis and DNA fragmentation assays confirmed that AEA induced cell death via apoptosis. AEA was also found to induce cell cycle arrest in MCF-7 cells at the G(0)/G(1) phase with no adverse cell cycle arrest effects on HMEC normal control cells. It was concluded that AEA isolated from the Malaysian tropical ginger represents a potential chemotherapeutic agent against human breast cancer cells with higher cytotoxicity potency than its analogue, ACA.

International audience; The stem bark of Phoebe grandis afforded one new oxoproaporphine; (-)-grandine A (1), along with six known isoquinoline alkaloids: (-)-8,9-dihydrolinearisine (2), boldine, norboldine, lauformine, scortechiniine A and scortechiniine B. In addition to that of the new compound, complete 1H- and 13C-NMR data of the tetrahydroproaporphine (-)-8,9-dihydrolinearisine (2) is also reported. The alkaloids' structures were elucidated primarily by means of high field 1D- and 2D-NMR and HRMS spectral data.

Schiff bases of 3,4-dimethoxybenzenamine 1–25 were synthesized and evaluated for their antioxidant activity. All the synthesized compounds were characterized by various spectroscopic techniques. In addition, the characterizations of compounds 13, 15 and 16 were supported by crystal X-ray determinations and their geometrical parameters were compared with theoretical DFT calculations at the B3LYP level of theory. Furthermore, the X-ray crystal data of two non-crystalline compounds 8 and 18 were theoretically calculated and compared with the practical values of compounds 13, 15, 16 and found a good agreement. The compounds showed good DPPH scavenging activity ranging from 10.12 to 84.34 μM where compounds 1–4 and 6 showed stronger activity than the standard n-propyl gallate. For the superoxide anion radical assay, compounds 1–3 showed better activity than the standard.

The essential oils of leaves and rhizomes (fresh and dried) of Elettariopsis curtisii collected from Jeli, Kelantan were isolated by hydrodistillation and were analyzed using capillary GC and GC/MS. The most abundant components in both leaf and rhizome oils were (E)-2-octenal (1.0–19.3%), (E)-2-decenal (17.4–69.4%) and (E)-2-decenoic acid (7.4–57.2%). None of the oils exhibited remarkable inhibition potential against the microbes Microsporum canis, Trichophyton mentagrophytes, Trichophyton rubrum, Pseudomonas aeruginosa, Pseudomonas cepacia, Staphylococcus aureus and Staphylococcus epidermidis except for the fresh rhizome oil which showed an MIC value of 0.938 μg/μL against T. mentagrophytes.

The essential oils from the dried leaves, pseudostems and rhizomes of Alpinia conchigera Griff. (KL 5049), collected from Jeli province of Kelantan, east coast of Peninsular Malaysia, were isolated by hydrodistillation. The collected oils were analyzed by capillary GC and GC–MS. Forty one compounds were identified, among which 13 have not been detected previously. The leaf, pseudostem and rhizome oils afforded 40, 33 and 39 constituents, respectively. The most abundant components in the leaf oil included β-bisabolene (15.3%), β-pinene (8.2%), β-sesquiphellandrene (7.6%), chavicol (7.5%) and β-elemene (6.0%), while β-bisabolene (19.9%), β-sesquiphellandrene (11.3%), β-caryophyllene (8.8%) and β-elemene (4.7%) were the main components in the pseudostem. In the rhizome, 1,8-cineole (17.9%), β-bisabolene (13.9%), β-sesquiphellandrene (6.8%) and β-elemene (4.0%) were the major components. The essential oils were also subjected to antifungal and antibacterial tests, using the minimum inhibitory concentration (MIC) method. Results revealed weak inhibitions against the microorganisms tested.

In the title compound, C16H16N2O3·H2O, the dihedral angle between the benzene rings is 30.27 (7)°. In the crystal, the components are linked by N—H⋯O, O—H⋯O and C—H⋯O inter­actions into a three-dimensional network.

1'-(S)-1'-Acetoxychavicol acetate (ACA) isolated from the Malaysian ethno-medicinal plant Alpinia conchigera Griff. was investigated for its potential as an anticancer drug. In this communication, we describe the cytotoxic and apoptotic properties of ACA on five human tumour cell lines. Data from MTT cell viability assays indicated that ACA induced both time- and dose-dependent cytotoxicity on all tumour cell lines tested and had no adverse cytotoxic effects on normal cells. Total mortality of the entire tumour cell population was achieved within 30 hrs when treated with ACA at 40.0 µM concentration. Flow cytometric analysis for annexin-V and PI dual staining demonstrated that cell death occurred via apoptosis, followed by secondary necrosis. The apoptotic effects of ACA were confirmed via the DNA fragmentation assay, in which consistent laddering of genomic DNA was observed for all tumour cell lines after a 24 hrs post-treatment period at the IC(50) concentration of ACA. A cell cycle analysis using PI staining also demonstrated that ACA induced cell cycle arrest at the G(0)/G(1) phase, corresponding to oral tumour cell lines. In conclusion, ACA exhibits enormous potential for future development as a chemotherapeutic drug against various malignancies.