One of the solutions is the supplying of calcium effervescent powder as a source of calcium. The source of calcium that has not been processed maximally is the clam shell. Calcium from the clam shells will be extracted by calcination method at 900 °C for 4hours. The extracted clam shells powder are tested using XRD and analyzed using the Rietveld method. The particle sizes of calcium are determined by the Scherer equation. The best calcium is formulated into 3 formulations with several variations in composition. Evaluation of calcium effervescent powder includes organoleptic test, water content and dispersion time. The extracted calcium crystal diffractogram shows the CaO compound with cubic structure and space group FM3M. The particle sizes of CaO nanoparticles from green shells and batik were 88.7597nm and 96.66566nm, respectively. The best CaO based on χ2 values ​​and particle sizes are CaO from green clamshells. The organoleptic test of the three formulations produced the same data as yellow, granular shape, and citrus aroma. Formulation three is the best formulation based on the low water content and short dispersion time.

Ceftriaxone is a third generation of cephalosporin antibiotics that commonly used in patients with ulcers. Ceftriaxone residues in the environment are degraded using Titanium dioxide (TiO2) nanoparticles. Degradation of ceftriaxone using TiO2 nanoparticles was influenced by environmental conditions, such as light sources, pH of the solution, the mass of TiO2 nanoparticles, and the length of radiation. The remained ceftriaxone was analyzed by using a spectrophotometer UV-visible. The toxicity of the solution after the degradation process was tested on Escherichia coli and the type of products resulted was analyzed using Liquid Chromatography-Mass Spectrophotometry (LC-MS). The optimum conditions in degrading 50 mL 250 ppm ceftriaxone was radiation under a mercury UV lamp (white), pH 8, and 100 mg of TiO2 nanoparticles for 9 hours. The degradation degree of ceftriaxone obtained was 96.52%, producing simpler compounds that not toxic to E. Coli.

Photoactivity of titanium dioxide (TiO2) can be improved by transformation to nanoparticles. Synthesis of TiO2 nanoparticles can be accomplished by a hydrothermal method and the product of this method is affected by types of

The popular use of ciprofloxacin is often irrational, so it causes environmental pollution such as resistance. The solution to overcome environmental pollution due to ciprofloxacin is degradation by using TiO2 nanoparticles. TiO2 nanoparticles performance is influenced by environment such as light source, pH solvent, duration of lighting and TiO2 nanoparticles mass. The residual levels determination of ciprofloxacin was carried out by using a UV-Vis spectrophotometer. Toxicity test of ciprofloxacin degradation products with TiO2 nanoparticles used Escherichia coli bacteria. Liquid Chromatography Mass Spectrometry (LCMS) was used to determine the type of ciprofloxacin degradation product with TiO2 nanoparticles. The optimum condition for the ciprofloxacin degradation with TiO2 nanoparticles is lighting for 5 hours by using a white mercury UV lamp and 50 mg TiO2 nanoparticles with pH solvent of 5.5. The toxicity of ciprofloxacin degradation product with TiO2 nanoparticles was low. The smallest degradation product identified with m/z was p-fluoraniline (m/z 111). Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

Antioxidant pentapeptides are pentapeptide compounds that have antioxidant activity. One of the pentapeptide compounds that have antioxidant activity is FWKVV. FWKVV is a linear pentapeptide with the amino acid sequence phenylalanine-tryptophan-lysine-valine-valine, which was first isolated to hydrolyzate the muscle protein of Miiuy croaker (Miichthysmiiuy). In addition to isolation, FWKVV compounds can be produced by the peptide synthesis method because this method requires a shorter time than the isolation method from natural materials. Synthesis methods commonly used are solution-phase peptide synthesis and solid-phase peptide synthesis (SPPS). However, the SPSS method is more efficient because it does not require purification in every process. The purpose of this study was to synthesize FWKVV compounds using the SPPS method and test their antioxidant activity. FWKVV has been synthesized using the SPPS method with HBTU/HOBt coupling reagent and Fmoc protective group. The FWKVV crud produced was 148.8 mg and had antioxidant activity against DPPH radicals with an IC50 value of 4.2 mg/mL.