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All Journal Jurnal Presipitasi : Media Komunikasi dan Pengembangan Teknik Lingkungan Indonesia Chimica Acta
Hardimas Prayudi
School of Metallurgy and Environment
Agriculture, Biological Sciences & Forestry Chemical Engineering, Chemistry & Bioengineering Earth & Planetary Sciences

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Performance Analysis of biosorption of Heavy Metal and Biodegradation PAH of Isolates Marine Sponges Symbiont Bacteria Ismail Marzuki; Andi Muhammad Asdar Marzuki; Hardimas Hardimas
Jurnal Akta Kimia Indonesia (Indonesia Chimica Acta) Volume 14, No 2: December 2021
Publisher : Hasanuddin University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20956/ica.v14i3.18333

Abstract

Heavy metal pollutants and polycyclic aromatic hydrocarbon contaminants, also known as PAHs, need attention from related parties, considering that their use is very wide, as well as their relatively high natural releases. Careless and uncontrolled handling has the potential to cause problems for creatures, especially in marine ecosystems. The aim of the study was to determine the performance of marine sponge microsymbiont isolates in heavy metal biosorption and PAH biodegradation. The method applied, pure isolates of marine sponge symbionts were cultured on NA media. The suspension of isolates was made using physiological 0.9 % NaCl solution. Suspension adapted 24 hours. The isolate suspension was interacted with heavy metals Cd2+ and As3+, each with a concentration of 100 ppm and naphthalene and anthracene with a concentration of 1000 ppm. Interaction time of 5, 10, 15, and 20 days. Results of the analysis showed the biosorption capacity of the bacterial isolate Sp6.B2 to Cd2+ = 83.190 %, while Sp8.B1 = 82.240 %. Biosorption performance of Sp6.B2 isolates against As3+ = 99.890 %, while Sp8.B1 = 99.894 %. The biodegradation performance of Sp6.B2 isolates had a higher aggressiveness towards naphthalene and anthracene test contaminants than Sp8.B1 isolates. These results indicate that the biosorption performance of Sp6.B2 ˃ Sp8.B1 isolates against Cd2+ contaminants and vice versa Sp6.B2 ˂ Sp8.B1 against As3+ biosorption, while the biodegradation performance of Sp6.B2 ˃ Sp8.B1 isolates both against naphthalene and anthracene test contaminants
Linking Degree of Deacetylation to Coagulation Efficiency of Crustacean Waste Chitosan in Water Treatment Sinardi Sinardi; Ismail Marzuki; Asriadi Asriadi; Andi Sry Iryani; Faisal Riza Basalamah; Andi Irsyam Mansyur; Hardimas Prayudi
Jurnal Presipitasi : Media Komunikasi dan Pengembangan Teknik Lingkungan Vol 23, No 2 (2026): July 2026
Publisher : Universitas Diponegoro

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14710/presipitasi.v23i2.533-542

Abstract

Turbidity removal remains challenging because stable colloids resist sedimentation, motivating the use of biodegradable coagulants such as chitosan derived from crustacean waste. However, an integrated quantitative linkage between the degree of deacetylation (DD), zeta potential evolution, and dose-dependent turbidity removal across pH is still limited for shell waste-derived chitosan. This study aimed to relate DD to the zeta potential behavior and coagulation efficiency of chitosan derived from green mussel, crab, and shrimp shells at pH 5, 7, and 9. At pH 7, shrimp-shell chitosan (DD 89.05%) achieved 98.38% turbidity removal at 190 mg/L, crab-shell chitosan (DD 87.64%) achieved 96.72% at 320 mg/L, and green mussel chitosan (DD 77.80%) achieved 95.08% at 300 mg/L [mean±SD, n=3].  The zeta potential shifted from −0.81 mV (untreated synthetic water) to +1.43 to +2.80 mV after dosing, indicating dominant charge neutralization with partial overcompensation. Overall, DD provides a practical screening descriptor for selecting locally sourced chitosan and optimizing the dose for sustainable turbidity control. Valorizing shell waste into effective coagulants may reduce the reliance on inorganic coagulants and support environmentally responsible water treatment practices. This study established an integrated DD zeta potential dose relationship across pH to explain and compare the coagulation performance of locally sourced shell-waste chitosan for turbidity removal. 
Co-Authors Andi Irsyam Mansyur Andi Muhammad Asdar Marzuki Andi Sry Iryani Asriadi Asriadi Faisal Riza Basalamah Ismail Marzuki Ismail Marzuki Sinardi