Pectin, a natural polysaccharide, has gained increasing attention due to not only its biomaterial properties but also its biomedical activities. One of the abundant sources of pectin is mangosteen ( Garcinia mangostana L.) rind. In this study, we characterized the pectin from Indonesian mangosteen rind extract and evaluated its antioxidant activity. Pectin was extracted in acid condition and evaluated its physicochemical properties by fourier transform infrared (FTIR), powder X-ray diffractometer (PXRD), water content, ash content, equivalent weight, methoxyl level and of galacturonic acid content. Furthermore, the antioxidant activity of pectin was also observed by 2,2-diphenyl-1-picrylhydrazyl (DPPH) method. Pectin was successfully extracted from dry weight of Indonesian mangosten rind with yield about 1,16 ± 0,17%, fine powder, brownish and odorless. FTIR and PXRD results showed that pectin from mangosteen rind extract was amorphous and similar characteristic with a commercial pectin. The chemical properties of pectin such as water content, ash content, equivalent weight, methoxyl level and of galacturonic acid level were 9.85 ± 0.12%, 3.91 ± 0.17%, 6330.76 ± 220.43 g/mol, 2.86 ± 0.05% and 75.98 ± 0.88%, respectively. In addition, pectin showed an antioxidant activity with the IC 50 about 161.94 ± 31.57 ppm. These results suggest that pectin from Indonesian mangosteen rind has the potential properties as biopolymers for biomedical applications with a low-methylated pectin and a moderate antioxidant activity.

Atenolol (ATE) is a cardio-selective β-blocker that is used in the treatment of hypertension over extended periods. However, ATE, like propranolol, has major potential for misuse as a performance-enhancing drug in several sports. Therefore, an efficient and selective separation method is required to detect and monitor the level of ATE in the body. This paper presents a molecularly imprinted polymer with specific and selective binding to ATE using precipitation polymerization. We show that when employed in an optimized molecular imprinted solid phase extraction (MI-SPE) protocol, recoveries of 93.65 ± 1.29% from spiked blood serum with excellent discrimination from other β-blocker drugs is possible. The methodology used in this study includes molecular modeling interaction between ATE and itaconic acid (ITA) as functional monomer, followed by determination of binding constants with spectrophotometry, synthesis of the polymer using precipitation polymerization and ending with characterization and application of polymers to extract ATE in serum. Docking analysis revealed a binding affinity between ATE and ITA of −2.0 kcal/mol with the formation of hydrogen bonding. The association constant between ATE and ITA was studied by UV titration in two different solvents, with evidence of an association constant 6.277 × 10 2 M −1 measured in acetonitrile: methanol (1:1). An optimized MI-SPE protocol was developed for the extraction of ATE from spiked blood serum, obtaining recoveries of 93.65% with excellent selectivity toward other β-blocker drugs.

MPT64 is a specific protein that is secreted by Mycobacterium tuberculosis complex (MTBC). The objective of this study was to obtain optimum culture conditions for MPT64 synthetic gene expression in Escherichia coli BL21 (DE3) by response surface methodology (RSM). The RSM was undertaken to optimize the culture conditions under different cultivation conditions (medium concentration, induction time and inducer concentration), designed by the factorial Box-Bhenken using Minitab 17 statistical software. From the randomized combination, 15 treatments and three center point repetitions were obtained. Furthermore, expression methods were carried out in the flask scale fermentation in accordance with the predetermined design. Then, the MPT64 protein in the cytoplasm of E. coli cell was isolated and characterized using sodium dodecyl sulfate polyacrilamide electrophoresis (SDS-PAGE) then quantified using the ImageJ program. The optimum conditions were two-fold medium concentration (tryptone 20 mg/mL, yeast extract 10 mg/mL, and sodium chloride 20 mg/mL), 5 h of induction time and 4 mM rhamnose. The average concentration of recombinant MPT64 at optimum conditions was 0.0392 mg/mL, higher than the predicted concentration of 0.0311 mg/mL. In conclusion, the relationship between the selected optimization parameters strongly influenced the level of MPT64 gene expression in E. coli BL21 (DE3).

Abstrak Antibacterial Activity Of Five Plant Ethanol Extract Against Staphylococcus Epidermidis Bacteria With Microdilution M7 -A6CLSI Method AbstractThe antibacterial activity of Leucaena leucocephala, Camellia sinensis, Psidium guajava L, Anredera cordifolia (Ten.) Steenis and Solanum nigrum L. leafs ethanol extract against Staphylococcus epidermidis using microdillution method has been studied. Using microdillution method with tetracycline, chloramfenicol and amoxicillin as antibiotic reference. Leucaena leucocephala, Camellia sinensis and Psidium guajava L. leafs ethanol extract had activity to inhibit bacteria. And the other leafs ethanol extract had unsignificant activity againts bacteria. The Minimum Inhibitory Concentration (MIC) of Leucaena leucocephala leafs ethanol extract againts Staphylococcus epidermidis were 62,5 µg/ml. The Minimum Bactericidal Concentration (MBC) of Camellia sinensis and Psidium guajava L were 125 µg/ ml.

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