− Clitoria ternatea or Commonly known blue pea, is a perennial climber crop native to Asian countries. The current study was aimed to evaluate the antimicrobial activity C. ternatea extract on food borne microorganisms and its antifungal effect on Penicillium expansum. The extract showed significant antimicrobial activity against 3 Gram positive bacteria, 2 Gram negative bacteria and 1 filamentous fungus on disc diffusion assay. The extract also showed good biocidal effect on all Gram positive bacteria tested and P. expansum. However, the kill curve analysis revealed that the fungicidal activity of the extract against P. expansum conidia was depend on the concentration of the extract and the time of exposure of the conidia to the extract. The scanning electron micrograph of the extract treated P. expansum culture showed alterations in the morphology of fungal hyphae. The germination of P. expansum conidia was completely inhibited and conidial development was totally suppressed by the extract, suggesting the possible mode of action of anthocyanin. Besides, the extract also exhibited 5.0-log suppression of microbial growth relative to control in the rice model. The results indicate the potential use of the C. ternatea anthocyanin as food biopreservative.

essential oil of Homalomena pineodora inhibits diabetic pathogens; however, the activity was not sustainable when applied as wound dressing. this study aims to synthesise the essential oil nanoparticle using chitosan. The nanoparticles were synthesised with ion gelation method, confirmed by spectroscopic analysis. The spherical nanoparticles display a size of 70 nm, with strong surface charge of +24.10 mV. The nanoparticles showed an initial burst release followed by a slow release pattern for 72 h, following the first order of kinetic. the release behaviour was ideal for wound dressing. the antimicrobial activity was broad spectrum. the formation of nanoparticle enhanced the antimicrobial efficacy of the essential oil. The nanoparticle also showed a concentration-dependent killing behaviour on time-kill assay. In the 3D collagen wound models, the nanoparticles reduced the microbial growth by 60-80%. In conclusion, H. pineodora nanoparticles showed pharmaceutical potential in inhibiting microbial growth on diabetic ulcers.

An extracellular xylanase was purified from the mesophilic fungus Penicillium rolfsii c3-2(1) IBRL. After three consecutive purification steps, the extracellular cellulase-free xylanase was successfully purified to homogeneity with a recovery yield of 24%. A single protein band of 35 kDa was detected by SDS-PAGE, which had an optimum catalytic activity at pH 5.0 and 50 °C. This purified enzyme was stable at pH 5 to 7, thermostable up to 55 °C, and retained up to 83% of its activity after 4 hours of pre-incubation. A kinetic study yielded estimated Km and Vmax values of 5.73 mg/mL and 691.6 µmol/min/mg, respectively. Thin layer chromatography experiments showed that the purified xylanase was capable of hydrolyzing xylotriose, xylotetraose, xylopentaose, and xylohexaose but not xylobiose, suggesting it is an endo-xylanase. Enzymatic hydrolysis of oil palm trunk residues by commercial enzymes supplemented with the purified xylanase showed a considerable increase in total sugar conversion compared with the commercial enzymes alone, suggesting that xylanase is a key enzyme in the hydrolysis of oil palm trunk residues.

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Application of microbial enzymes for paper deinking is getting tremendous attention due to the rapidly increasing of waste paper every year. This study reports the deinking efficiency of laser-printed paper by the lignocellulolytic enzyme from Penicillium rolfsii c3-2(1) IBRL strain compared to other enzyme sources as well as commercial available enzymes. High enzymatic deinking efficiency of approximately 82 % on laser-printed paper was obtained by pulp treatment with crude enzyme from P. rolfsii c3-2(1) IBRL. However, this crude enzyme was found to reduce the paper strength properties of the pulp based on the results of tensile, tear and burst indices, most probably due to the cellulose degradation. This was further proven by the low viscosity of paper pulp obtained after enzymatic treatment and increasing of sugar production during the treatment. Balancing to this detrimental effect on paper pulp, high deinking efficiency was achieved within a short period of time, in which the enzymatic treatment was conducted for 30 min that enabled contribution to higher brightness index obtained, thus promoting savings of time and energy consumption, therefore environmental sustainability. Extensive research should be conducted to understand the nature and mechanism of enzymatic deinking process by the crude enzyme from P. rolfsii c3-2(1) IBRL in order to improve paper strength properties.