No abstract

Jackfruit (Artocarpus heterophyllus) is a popular and valuable fruit in Malaysia. The present study aims to determine the proximate composition, mineral contents and functional properties of jackfruit seed powder (JSP) of Mastura cultivar and assess the toxicity of the jackfruit seed crude extract using embryonic zebrafish model. The proximate analysis results obtained showed that the JSP had 69.39% carbohydrate, 13.67% protein, 10.78% moisture, 2.41% ash, 0.75% fat and 3.00% crude fiber. The energy value reported was 345 kcal/100 g. Most abundant mineral found in the JSP was potassium (7.69 mg/g) followed by phosphorus (1.29 mg/g), magnesium (1.03 mg/g), calcium (0.41 mg/g) and sodium (0.05 mg/g). Water absorption capacity (2.35 g/g), oil absorption capacity (1.14 g/g) and bulk density (0.67 g/cm 3) were recorded for the JSP. The values for swelling power and solubility were 4.12 and 9.98, respectively. Furthermore, the various concentrations of jackfruit seed crude extract showed lethal developmental effects against zebrafish embryos during 96 hrs of exposure duration. Increased mortality was observed in embryos after exposure to concentrations above 15.625 µg/mL in dose and time-dependent manner. Based on the results, it can be concluded that JSP has great potential to be utilized in the formulations of food and other functional products. Additionally, the presence of toxic effects in the crude extract of JSP indicates the future studies required in isolating and identifying the compounds that might be responsible for the toxicity.

No abstract

The carbon-to-nitrogen (C:N) ratio in the biomass of microfungi tends to be quite different (e.g. 10-15) compared with the C:N ratio in the red pigments (e.g. >20) of the fungus Monascus ruber. Therefore, determining an optimal C:N ratio in the culture medium for maximizing the production of the pigments is important. A culture medium composition is established for maximizing the production of the red pigment by the fungus M. ruber ICMP 15220 in submerged culture. The highest volumetric productivity of the red pigment was 0.023 AU L(-1) h(-1) in a batch culture (30 °C, initial pH of 6.5) with a defined medium of the following composition (g L(-1)): glucose (10), monosodium glutamate (MSG) (10), MgSO4·7H2O (0.5), KH2PO4 (5), K2HPO4 (5), ZnSO4·7H2O (0.01), FeSO4·7H2O (0.01), CaCl2 (0.1), MnSO4·H2O (0.03). This medium formulation had a C:N mole ratio of 9:1. Under these conditions, the specific growth rate of the fungus was 0.043 h(-1) and the peak biomass concentration was 6.7 g L(-1) in a 7-day culture. The biomass specific productivity of the red pigment was 1.06 AU g(-1) h(-1). The best nitrogen source proved to be MSG although four other inorganic nitrogen sources were evaluated.