Production of Phenylpyruvic Acid by Engineered L-Amino Acid Deaminase from Proteus Mirabilis

Objectives This study aimed to develop an efficient enzymatic strategy for the industrial production of phenylpyruvate (PPA) from L-phenylpyruvic acid (L-Phe). Results L-amino acid deaminase from Proteus mirabilis (L-pmAAD) was expressed in E. coli BL21(DE3) and modified to release product inhibition by employing conformational dynamics engineering. Based on structural analysis, two residues (E145A/L341A) were identified for reducing interactions between the product and enzyme and increasing flexibility of the protein, thereby facilitating the product release. The mutant M2E145A/E341A exhibited a 3.84-fold reduction in product inhibition and a 1.35-fold increase in catalytic efficiency in comparison to the wild type. Finally, 81.2 g/L PPA production with a conversion of 99.6% was obtained in a 5-L bioreactor. Conclusion The engineered catalyst can significantly reduce product inhibition and facilitate the effective industrial synthesis of PPA.

Retrospective, Perspective and Prospective of B-Complex Vitamins: Encapsulation of Vitamins and Release from Vitamin-Loaded Polymers

Vitamins are regarded as vital nutrients because, when combined, they performed hundreds of functions in the body. They strengthen bones, heal wounds, and boost your immune system. In addition, they transform food into energy and heal cellular damage. In this regard, B-complex vitamins, such as thiamine, riboflavin, and niacin are soluble vitamins that serve as coenzymes in energy metabolism enzymatic activities which building blocks of a healthy body. However, B-complex vitamins are sensitive to light, pH conditions, and temperature. Consequently, they must be encapsulated before they may be used in pharmaceuticals. Recently, it is mainly focused on reducing drug degradation or loss, increase drug bioavailability, limit adverse effects, and improve drug accumulation in the targeted location. To maintain optimum bioavailability during a defined term of therapy, the fraction of drug dosage released from a controlled release product must be significant enough to adjust for the quantity of active drug metabolized and/or eliminated from the body over the same period. Drug release systems also aim to increase the effectiveness of the drug and treat the damaged area. In this chapter, it is aimed to study the production of the vitamin-loaded polymer systems in various forms, such as micro/nanoparticles, micelle, hydrogel, liposome, and nanofiber, as well as release studies in pharmaceutical and biomedical applications.

PENGEMBANGAN MODUL DIGITAL BERBASIS SCL UNTUK MATA KULIAH MATEMATIKA TERAPAN JURUSAN NAUTIKA

This study aims to make the development product in the form of an applied mathematics digital module that is used as teaching material for cadets at the Nautics Department at the Surabaya Shipping Polytechnic. This development product includes teaching material and simulations that can be executed through the links available in teaching materials to facilitate understanding the material. The research method uses the waterfall development model with 5 (five) stages, namely needs analysis, design and implementation, testing, product release, product maintenance. Development products are tested to content, media experts, and development design experts to obtain product feasibility. The development products were then tested in small groups (6 cadets) and large groups (26 cadets) and allied teacher assessments. The average results of the feasibility assessment by experts amounted to 79.2% or very well qualified. The product feasibility assessment from the small group test was 83.6%, while the product feasibility assessment from the large group test was 85.7%. The scores of allied lecturers were 93.3%. The digital module of applied mathematics is effective to be used in learning. The addition of illustration/figure and simulation really helps the cadets in understanding the material. The digital form facilities the cadets to open and read the materials whenever and wherever using handphone or laptop. As a product dissemination, an applied digital math module can be downloaded with simulations of each topic via the internet.

Comparison of different slow-release nutrient composites produced to stimulate microorganisms

Concern for environmental quality has increased in society because industrial and technological development has released high levels of contaminants into the environment, such as hydrocarbons. A technique widely used for bioremediation is biostimulation, which may be enhanced by microencapsulation. This research formulated slow-release nitrogen and phosphorus compounds using different polymer (Alginate/Capsul®, carboxymethyl cellulose) matrices and compared them with the agricultural product Osmocote® and mineral medium Bushnell-Haas as hydrocarbonoclastics biostimulation agents in the environment for pollutant bioremediation. N (nitrogen) and P (phosphorus) were immobilized using lyophilization and ionic gelation techniques. Experiments were conducted using encapsulated material and evaluated for biomass production, glucose consumption as organic carbon source and N and P supply. The immobilized carboxymethyl cellulose compound showed the best results of glycosidic degradation (66.7%) and microbial biostimulation (350 mg L-1 protein) compared to systems containing free nutrients (11.3% and 150 mg L-1 degradation glycosidic and microbial biostimulation, respectively). Thus, this compound is a potential slow release product for bioremediation processes.