Mariani Rajin

Effect of various formulation on viscosity and melting point of natural ingredient based lipstick

Lipstick is one of the decorative cosmetic products that command a unique market. Advanced technology has been used to manufacture modem lipsticks with vast functionality. In the last quarter of twentieth century, cosmetic industries exist with technology of their own. Every year, users were introduced with various new cosmetics products of the latest trend. The quality of lipstick is directly linked to the basic material used in the formulation. Varying the ratio of the ingredient used determines the final product characteristic. A common problem in pre-formulation of the cosmetic product is the optimisation of the mixture composition aimed to obtain a product with the required characteristic. In this work, various compositions of natural waxes, oils, and colorant were used to prepare the lipstick formulations. Mixture design was performed to obtain the optimum formulation. Twenty-five combination components were selected according to the D-optimal criterion. The viscosity and melting point of the lipsticks were studied. Contour graphics were formed to assess the change in the response surface in order to understand the effect of the mixture composition on lipstick characteristics.

Variation of reaction stages and mole composition effect on melamine-urea-formaldehyde (MUF) resin properties

MUF resin is widely used as an adhesive in wood industries, coating technology, paper industries and a main material in kitchenware production. In various applications, different resin properties are needed to suit its application. Important resin properties are for example higher resin solubility, low curing period with lower temperature and catalyst amount, good stability for longer shelf life, and lower free )brmaldehyde emission, as formaldehyde is very toxic, and can cause cancer. One of the factors that affecting the MUF resin properties is the mole composition. The mole composition is a ratio of/brmaldehyde to amino compound i.e. melamine or urea, in each reaction stages. Besides that addition of other chemical such as sorbitol, may be added to enhance the resin properties. In Turin (1998)and Gapud et al. (1999) researches, addition of sorbitol has improve the resin stability and solubility in water and also cured resin flexibility. Using experimental design such as Surface Response Method optimises the product formulation. This method is more satisfactory and effective than other methods such as classical one-at-a-time or mathematical methods because it can study many variables simultaneously with a low number of observations, saving time and costs. Hence in this research, statistical experimental design or mixture design is used in this work in order to optimise the MUF resin formulation.

Effect of temperature on Candida antartica lipase B activity in the kinetic resolution of acebutolol

Thermodynamic studies of free Candida antartica lipase B in kinetic resolution of acebutolol have been carried out to characterize the temperature effects towards enzyme stability and activity. A decreased in reaction rate was observed in temperature above 40oC. Thermodynamic studies on lipase deactivation exhibited a first-order kinetic pattern. The activation and deactivation energies were 39.63 kJ/mol and 54.90 kJ/mol, respectively. The enthalpy and entropy of the lipase deactivation were found to be 52.12 kJ/mol and -0.18 kJ/mol, respectively.

A Current Review on the Application of Enzymes in Anaerobic Digestion

Although the anaerobic digestion process is widely applied in waste management, it is recognised that the hydrolysis step in the treatment is a bottleneck that can restrict the rate that methane is produced. Enzyme addition during hydrolysis of a substrate has been reported as a promising alternative to overcome this limitation. This chapter presents a review of the supplementation of enzymes to facilitate the hydrolysis process of various types of substrates in the anaerobic digestion system.