No abstract

Plants Zingiber officinale (ginger) and Zingiber zerumbet (lempoyang) of Zingiberaceae family have been traditionally used as treatment for stomach problems, nausea, vomiting, epilepsy, sore throat, muscular pains and several other disorders. In this study, essential oils from both plants were investigated for their efficacy on antibacterial activity against two Gram positive (Staphylococcus aureus, and Bacillus cereus) and two Gram negative (Pseudomonas aeruginosa and Escherichia coli) bacteria species using the disc diffusion assay. A zone of inhibition was compared with the standard antibiotic chloramphenicol, whilst a blank disc impregnated with the methanol was used as negative control. At concentration 20 mL/disc, Z. officinale essential oil produced zone of inhibition ranging from 16 to 36 mm, while Z. zerumbet essential oil produced zone inhibition ranging from 11 to 14 mm. These findings showed Z. officinale essential oil inhibited the growth of all tested bacteria with large zone of inhibition. The most susceptible bacteria was B. cereus while the lowest was P. aeruginosa. It can be concluded that, Z. officinale and Z. zerumbet essential oils might provide potential therapeutic agents against bacterial infection.

Response surface methodology (RSM) was employed to optimize the extraction of herbal plant of Annona muricata L. using Box-Behnken Design (BBD). The Box-Behnken Design (BBD) with three factors and two responses (yield and total solid content) was implemented. The processing parameters of A. muricata leaves by soxhlet extraction were solvent to raw material ratio, ethanol concentration, and duration of extraction using soxhlet extractor. The presence of acetogenins compounds was screened by High Performance Liquid Chromatography. Optimum condition with the solvent to raw material ratio (1:5.92), ethanol concentration (1.67 %), and duration of extraction (6.84 hours) was obtained and further analyzed with antioxidant tests. Analyses showed the A. muricata leaves contained high total phenolic and flavonoid contents which corresponding to the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity test. The DPPH result showed that the extract has the highest percentage of scavenging activity with the inhibitory concentration (IC50) value of leaves is 0.243 mg/mL + 0.001 nearly comparable to butylated hydroxyanisole (BHA) and ascorbic acid (Vit. C), which indicated that the leaves also have higher free radical scavenging activity compared to these commercial standards. Besides, the presence of primary; polysacharide (21.85 % + 0.001), protein (19.59 % + 0.000), glycosaponin (18.87 % + 0.001) and secondary; phenolic (47.26 mg GAE/1g + 0.001), flavonoid (22.12 mg CE/1g + 0.001) metabolites in A. muricata leaves suggested that the leaves contained strong antioxidant properties that are believed can act as anticancer agent for the body.

Ergosterol, a component of fungal cell membrane, has been frequently detected as an indicator of fungal presence and mass in environmental samples like soil. However, its detection in major pathogenic fungal species has not been investigated. In this study, the ergosterol contents of ten pathogenic fungal species were determined. Liquid chromatography was used for the detection and quantification of ergosterol extracted from fungal broth cultures. Results showed that ergosterol eluted as a single, well resolved peak in the chromatogram profiles of all tested fungi. Based upon relative amounts of ergosterol produced per fungal mycelial dry weight, three groups of fungal pathogens were identified, namely low ergosterol (Aspergillus niger, Candida albicans and Cryptococcus neoformans at 4.62, 6.29 and 7.08 µg/mg, respectively), medium ergosterol (Fusarium solani, Aspergillus fumigatus, Mucor sp., Penicillium sp., Cryptococcus gattii and Rhizopus sp. at 9.40, 10.79, 10.82, 11.38, 12.60 and 13.40 µg/mg, respectively), and high ergosterol (Candida tropicalis at 22.84 µg/ mg), producers. Ergosterol was not detectable in bacterial samples, which were included as controls. This first report on ergosterol detection in major pathogenic fungal species indicates that ergosterol may be used as a biomarker to diagnose invasive fungal infections in clinical samples. ABSTRAK Ergosterol, yang merupakan komponen membran sel fungus, seringkali dikesan sebagai petunjuk kehadiran dan jumlah fungus dalam sampel daripada persekitaran. Walau bagaimanapun, pengesanan ergosterol dalam fungus patogen utama belum dikaji. Dalam kajian ini, kandungan ergosterol dalam sepuluh spesies fungus patogen telah ditentukan. Kaedah kromatografi cecair digunakan untuk mengesan kehadiran dan penentuan kuantiti ergosterol yang diekstrak daripada kultur kaldu fungus. Berdasarkan kuantiti relatif ergosterol yang terhasil pada miselia fungus (berat kering), tiga kumpulan dikenal pasti iaitu mengandungi, ergosterol rendah (Aspergillus niger, Candida albicans dan Cryptococcus neoformans pada 4.62, 6.29 dan 7.08 µg/mg masing-masing), ergosterol sederhana (Fusarium solani, Aspergillus fumigatus, Mucor sp., Penicillium sp., Cryptococcus gattii dan Rhizopus sp. pada 9.40, 10.79, 10.82, 11.38, dan ergosterol tinggi (Candida tropicalis pada 22.84 µg/mg). Ergosterol tidak dapat dikesan pada sampel bakteria yang digunakan sebagai kawalan. Laporan pertama pengesanan ergosterol pada fungus patogen utama ini, menunjukkan bahawa ergosterol mungkin boleh digunakan sebagai biomarker untuk pendiagnosan jangkitan fungus invasif dalam sampel klinikal. Kata kunci: HPLC; ergosterol; biomarker; patogenik; fungus JSKM16(2) 3.indd 15

Chitin is a polysaccharide component of the inner cell wall of fungi that has been used to estimate fungal invasion in plant products. However, its detection in major pathogenic fungal species has not been investigated. The present study aimed to determine the chitin contents of pathogenic fungal species in order to evaluate its diagnostic potential as a biomarker for fungal infections. High performance liquid chromatography (HPLC) was used to measure chitin content. Pure chitin was acid hydrolyzed and the fluorescence of 9-fluorenylmethylchloroformate (FMOC-CI) derivatives of glucosamine produced were measured. The chitin contents of ten pathogenic fungal isolates were determined per mycelial dry weight. They varied from 18.61 (± 0.09) to 47.12 (± 0.50) μg/mg dry mycelial weight. Candida albicans and Cryptococcus neoformans exhibited the highest and lowest levels of chitin, respectively. Based upon relative amounts of chitin produced, three groups namely: high (Candida albicans, Cryptococcus gattii, Aspergillus niger and Penicilliumat 47.12, 46.98, 46.05, and 44.15 μg/mg respectively), medium (Rhizopus, Aspergillus fumigatus, Fusarium solani, andMucor at 36.61, 36.30, 35.03, and 34.84 μg/mg, respectively), and low (Candida tropicalis and Cryptococcus neoformans at 20.78 and 18.61 μg/mg, respectively), were identified. Chitin was not detectable in bacterial isolates used as controls. The chitin detection method offers a sensitive and specific tool for the quantification of chitin in pathogenic fungal isolates. The detection of chitin may be a useful assay for the diagnosis of fungal infections in clinical samples.