The Influence of IAA-Producing Bacteria on the Antioxidant Activity of Chlorella vulgaris Using the DPPH Method and In Silico Studies

Department of Biology, Faculty of Mathematics and Science, Universitas Negeri Malang, Semarang Street 5, 65112, Malang City, East Java, Indonesia

^* Corresponding author: sitoresmi.prabaningtyas.fmipa@um.ac.id

Abstract

Chlorella vulgaris are one of the biological materials widely utilized due to its natural antioxidant content. One effort to optimize the antioxidant content in microalgae can be done through co-culture with bacteria. This research was conducted to determine the effect of addition bacteria, specifically IAA-producing bacteria, on the antioxidant activity of C. vulgaris using the DPPH method and to analyze the potential active compounds in C. vulgaris as antioxidants through in silico methods. The treatments provided are 0 mL, 18.75 mL, 37.5 mL, and 75 mL during co-culture. The collection of active compounds using a database to analyze the interactions between compounds and target proteins and compare them with control compounds. The results show that the addition of bacteria at a concentration of 75 mL can increase biomass and has the best IC50 value of 14.0963, classifying it as a very strong antioxidant. The 3-hydroxyflavone, flavanone, isoflavone, and isosinensetin have antioxidant potential that is not much different from the control compound butylated hydroxytoluene (BHT). 3-hydroxyflavone and flavanone dominate in their potential as antioxidants with a higher binding affinity (-7.3 kcal/mol) compared to BHT (-6.5 kcal/mol).