Claim Missing Document
Check
Articles

Found 2 Documents
Search

Study of Congo Red Adsorption by Chitosan-Graphene Oxide (Chitosan-GO) Composite Synthesize with Hydrothermal Synthetic Method: Optimization and Determination Condition Desnelli Desnelli; Siska Safitri; Eva Musifa; Afreni Hamidah; Suheryanto Suheryanto; Ady Mara; Muhammad Said
IJFAC (Indonesian Journal of Fundamental and Applied Chemistry) Vol 10, No 2 (2025): June 2025
Publisher : IJFAC (Indonesian Journal of Fundamental and Applied Chemistry)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24845/ijfac.v10.i2.101

Abstract

This research aims to synthesize chitosan-graphene oxide (chitosan-GO) material using the hydrothermal method at varying material ratios and adsorption studies on Congo red. Chitosan-GO composites were synthesized with mass ratios of (1:1), (1:3) and (1:5). The synthesized chitosan-GO composite was applied to absorb Congo red dye. The adsorption process is carried out by varying pH, contact time, concentration and temperature. The chitosan-GO composite was characterized using XRD, BET and SEM-EDS. The results of XRD characterization of the chitosan-GO composite with a ratio of 1:1 showed a diffractogram of 2θ = 22.3°, at a ratio of 1:3 the diffractogram angle was 2θ = 22.1°, while the ratio (1:5) of the diffractogram peak obtained was 2θ = 22.8°. The surface area obtained in chitosan-GO composite was 11.60 m2/g. The morphology of the chitosan-GO composite (1:5) is in the form of crystalline lumps with the constituent elements C (65.98%), O (32.68%), Na (0.22%) and S (0.09%). Adsorption of Congo red dye using chitosan-GO composite obtained optimum conditions at pH 7, contact time 50 minutes, Congo red concentration 45 mg/L and temperature 50°C. The adsorption isotherm is in accordance with the Langmuir isotherm model and the maximum adsorption capacity (Qm) is 10.245 mg/g.
The Effect of Oxidative Stress on Growth and Antioxidant Activity of Microalgae Oocystis sp Eva Musifa; Mega Warni; Ramanisa Muliani Talib; Abdi Dharma; Elida Mardiah; Yuniar Harvianti; Indah Indah; Alinda Tania
IJFAC (Indonesian Journal of Fundamental and Applied Chemistry) Vol 10, No 1 (2025): February 2025
Publisher : IJFAC (Indonesian Journal of Fundamental and Applied Chemistry)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24845/ijfac.v10.i1.30

Abstract

This study was conducted to see the effect of growth and antioxidant activity of microalgae Oocystis sp before and after adding NaOCl to Growmore medium combined with urea. Antioxidant activity test was conducted by calculating IC50 spectrophotometrically with the 1,1-diphenyl-2-picrylhydrazyl (DPPH) method. Oocystis sp extract was obtained by sonication and maceration process with methanol solvent. The results showed the best growth curve for the growth of microalgae Oocystis sp in a mixture of Growmore medium 0.02% b/v and Urea 0.002% b/v. These results also showed a decrease in Oocystis sp growth in a mixture of Growmore medium 0.02% b/v and Urea 0.002% b/v with the lowest growth decrease in the addition of NaOCl with a concentration of 0.01%. The IC50 value of Oocystis sp extract in methanol solvent has high antioxidant activity in Growmore 0.02% b/v + Urea 0.002% b/v medium, which is 55.5862 mg/L. It can be concluded that NaOCl affects the growth and antioxidant activity of microalgae Oocystis sp, but at certain concentrations NaOCl experienced a negative effect.Keywords: Microalgae, Oocytis sp, Oxidative Stress, Growth, Antioxidant