Semarang, Friday | August, 12th 2022

The closed final exam is the end of the journey of a doctoral student at Diponegoro University. Stages in achieving a doctorate degree is indeed uneasy, it gets through various stages of attending lectures, proposal colloquium, seminar results, feasibility exams and scientific publication process with so full of struggle. On August 12, 2022, the Aquatic Resources Management doctoral study program again created the 175th new doctorate named Yeni Sulistiyani with Student Number 26010117510006.

The closed final exam takes place in a hybrid system in Building J Room 305 and virtually through Zoom Meeting at 13.00-15.30 Western Indonesian Time. The dissertation research presented entitled “Antibacterial Activity of Food Pathogens from Fukosantin Sargassum brown Algae from Lombok Waters, West Nusa Tenggara”. Stages studied by Promovenda are: 1) Sampling with nesting plot Method; 2. identification of Sargassum species molecularly; 3) Analyze fukosantin concentration by purification using column chromatography; 4) analyze the isomers of fucosantin using KCKT and 1D NOE NMR; 5) identify the activity of fucosantin against Test bacteria (B. cereus and S. flexneri) using agar diffusion method and determine KHM by microdilution broth method; and 6) examine the mechanism of inhibition of fukosantin as antibacterial by analyzing cellular leakage, metal ion leakage and morphology.

In conclusion, Promovenda dissertation writing gives a review that Fukosantin shows higher antibacterial activity against S. flexneri with a greater drag zone compared to B. cereus. The results of the Ca2+ and Mg2+ metal ion leakage test, indicate that both test bacteria metal ions are released out of the cell. S. flexneri has greater leakage of CA ions (67.66%) than B. cereus (55.64%). Whereas in MG ion leakage, ions are released in B. cereus is larger (57.68%) compared to S. flexneri (46.10%). Morphologically, exposure to fukosantin causes damage to test bacterial cells. On B. cereus, fukosantin cause elongation, surface destruction and cell lysis. As for S. flexneri, fukosantin cause lysis of bacterial cells.

Closed exam led by Agus Trianto, ST, M.Sc, Ph.D (Vice Dean for Academic and Student Affairs, FPIK), as the leader of the examination session and internal examiner, accompanied by Dr. Aninditia Sabdaningsih, S.Si., M.Si. (Head of Study Program), as the Secretary of the examination session with members of The Examiner team consisting of; Prof. Ir. Ali Munawar, M.Sc., Ph.D. (External Examiner); Prof. Dr. Ir. By Prayitno, M.Sc. (Internal Examiner); Dr. Ir. Haeruddin, M.Si (Co-promoter II); Prof. Norma Afiati, M.Sc, PhD (Co-promoter I) and Prof. Dr. Ir. Agus Sabdono, M.Sc (Promoter).

Based on the results of the assessment of the examiners team closed exam declared that Yeni Sulistiyani with student number 26010117510006, graduated with several records and became the 175th graduate of Diponegoro University, Faculty of Fisheries and Marine Sciences doctoral program in Aquatic Resources Management. Congratulations and success on your new title Dr. Yeny! Keeping up the work in the development of Science and make a real contribution to the welfare of society, maintaining the good name of the Faculty of Fisheries and Marine Sciences and the beloved alma mater of Diponegoro University.