Muhammad Nor Omar

The essential oil of greater galanga (Alpinia galanga) from Malaysia

Abstract The essential oil of A. galanga, a common spice in Malaysia, was prepared from fresh and dried rhizomes and analysed by means of capillary GC and GC/MS. Forty components were identified (only three of which were previously reported), accounting for 83–93% of the oil, depending on its method of preparation. Apart from monoterpenes, monoterpene alcohols and esters, and sesquiterpenes, also methyleugenol, eugenol acetate, chavicol (4-allylphenol) and chavicol acetate were present. This is the first time the latter substance has been reported in nature. Standardization of GC is proposed and tentatively applied towards a more systematic use of the Kovats indices as an aid in the identification of the constituents of essential oils.

Antifungal activity of Andrographis paniculata extracts and active principles against skin pathogenic fungal strains in vitro

Context: Andrographis paniculata Nees. (Acanthaceae) is an annual herbaceous plant widely cultivated in southern Asia, China, and Europe. It is used in the treatment of skin infections in India, China, and Malaysia by folk medicine practitioners. Objective: Antifungal activity of the whole plant extracts and isolation of active principles from A. paniculata were investigated. Materials and methods: Dichloromethane (DCM) and methanol (MEOH) extracts of A. paniculata whole plant were screened for their antifungal potential using broth microdilution method in vitro against seven pathogenic fungal species responsible for skin infections. Active principles were detected through bioguided assays and isolated using chromatography techniques. Structures of compounds were elucidated through spectroscopy techniques and comparisons were made with previously reported data for similar compounds. Results: DCM extract revealed lowest minimum inhibitory concentration (MIC) value (100 μg/mL) against Microsporum canis, Candida albicans, and Candida tropicalis, whereas MEOH extract revealed lowest MIC (150 µg/mL) against C. tropicalis and Aspergillus niger. DCM extract showed lowest minimum fungicidal concentration (MFC) value (250 µg/mL) against M. canis, C. albicans, C. tropicalis and A. niger, whereas MEOH extract showed lowest MFC (250 µg/mL) against Trichophyton mentagrophytes, Trichophyton rubrum, M. canis, C. albicans, C. tropicalis and A. niger. Bioassay guided isolation from DCM and MEOH extract afforded 3-O-β-d-glucosyl-14-deoxyandrographiside, 14-deoxyandrographolide, and 14-deoxy-11,12-didehydroandrographolide as antifungal compounds. The lowest MIC (50 µg/mL) and MFC (50 µg/mL) was exerted by 14-deoxyandrographolide on M. canis. Discussion and conclusion: This is first report on the isolation of antifungal substances through bioassay-guided assay from A. paniculata. Our finding justifies the use of A. paniculata in folk medicines for the treatment of fungal skin infections.

Laccase enzymes: purification, structure to catalysis and tailoring.

Laccases belong to the multicopper binding protein family that catalysis the reduction of oxygen molecule to produce water. These enzymes are glycosylated proteins and have been isolated and purified from fungi, bacteria, plant, insects and lichens. The variety of commercial and industrial application of laccases has attracted much attention towards the research addressing different aspects of the protein characterization, production and fit for purpose molecule. Here we briefly discuss the purification, catalytic mechanism in light of available understanding of structure-function relationship and the tailoring side of the protein, which has been the subject of recent research. Purification strategy of laccases is a method of choice and is facilitated by increased production of the enzyme. The structure-function relationship has given insights to unfold the catalytic mechanism. Site directed mutagenesis and other modification at C-terminal end or surrounding environment of copper centres have shown promising results to fit for purpose aspect, with a lot remains to be explored in glycosylation status and its alteration.

Physicochemical and antioxidant characteristics of Baccaurea angulata fruit juice extract

The purpose of this study was to explore the physicochemical and antioxidant characteristics of Baccaurea angulata fruit juice extract. Freeze-dried whole fruit (FDWF), freeze-dried berry (FDB), and freeze-dried skin (FDS) of B. angulata were analyzed for total phenolic, total flavonoid, total anthocyanin, and antioxidant activities. FDS recorded the highest moisture and ash content, protein, total fat, and water activity, compared to FDWF and FDB. FDS also contained the highest total phenolic, total flavonoid, and total anthocyanin, while FDWF recorded the highest in scavenging xanthine oxidase (35.9%) and ferric reducing activity (44.9 μM TE/g). FDS, however, showed the highest DPPH (102.66 mg AA/100 g) and TEAC (847.46 mg TE/100 g) values. DPPH, TEAC and FRAP were strongly correlated with total phenol (r = 0.979; 0.948; 0.997) and total flavonoid (r = 0.987; 0.960; 0.992). Total anthocyanin had no correlation with DPPH and TEAC, but moderately with FRAP (r = 0.734). Physicochemical and antioxidant characteristics of B. angulata may indicate that this fruit may impart health benefits when consumed and can be suggested as a good source for nutraceutical beverages. Keywords: Antioxidant properties, Baccaurea angulata , freeze-dried fruit, nutritional composition, physicochemical. African Journal of Biotechnology Vol. 12(34), pp. 5333-5338

Microbial Transformation of Natural Products

This article revises the current state of microbial transformation use in natural products. It represents the results of the most recent reports. Due to the importance of this transformation, there is still a strong need to intensify the direction of microbial transformation of the natural product compounds, besides exploiting more microorganisms that might be the used biocatalysts in producing the novel materials for pharmaceutical purposes.

Investigation of antioxidant activity and phytochemical constituents of Artocarpus altilis

The phytochemical screening study and the antioxidant activity test of the twigs of Artocarpus altilis has been done for the first time. The Artocarpus genus is known to produce a large number of secondary metabolites, and is specifically rich in phenylpropanoids such as flavonoids and flavones. Results of this study indicated that A. altilis (twigs) contain terpenoids, saponins, phenolic group, flavonoids, glycoside, steroids and tannins, while alkaloid test yielded negative result. Investigation on these chemical compounds was done using the standard technique for assay of phytochemical constituents, with modification. The dried plant was extracted by using soxhlet apparatus using three solvents namely hexane, dichloromethane (DCM) and methanol, and it was observed that the plant has a characteristic of antioxidant using DPPH assay. DCM extract of Artocarpus altilis has a remarkable antioxidant activity with an IC50 value of 0.015 mg/ml compared with the standard butylated hydroxytoluene (BHT). This finding supports the possibility of using this plant for medicinal treatments.

Effects of bioactive constituents extracted from Musa x paradisiaca flower on milk production in Vivo

Many plants are reputed to possess galactagogue activity that can be consumed to increase milk production for the need of the young. These plants should have contained possible substances that interact and affect lactation in mothers. In this research, two compounds (C1 and C2) were extracted from Musa x paradisiaca flower to determine its effect on milk production. 30 lactating rats of Spraque Dowley strain were daily administered with samples started from Day 5 through Day 15 of lactation using feeding tubes. The performance of milk production were measured a day after, started from Day 6 through Day 16 by means of weight-suckle-weight method after a 6 hr separation of litters from their dams. Results of the studied compounds were statistically analyzed and compared to the aqueous crude extract, metachlopromide and control groups using SPSS by means of ANOVA at 0.01 level of significant. Milk production of C1 and aqueous crude extract groups were significantly higher compared to C2, metachlopromide, and control groups. C1 was identified to increase milk production by 28.03%, while aqueous crude extract by 24.87%. The mean of milk yield within the given suckling period in gram of crude extract, C1, metachlopromide, C2, and control group were 4.86, 4.65, 3.76, 3.68 and 3.63, respectively. The peak lactation time of the experimental groups was either at Day 13 or Day 14 of lactation period. It was concluded that the bioactive compound (C1) exist in the flower could be the possible compound which affected milk production. The extract from Musa x paradisiaca flower could be utilised to increase milk yield, thus its function as lactogenic food is recommended for mothers of inadequate milk production.