Judul: Biologi Reproduksi Ikan Tongkol (Euthynnus affinis Cantor, 1849) di Perairan Selat Sunda
Abstrak: Ikan tongkol (Euthynnus affinis) atau yang dikenal dengan nama ikan tongkol kurik atau ikan tongkol komo merupakan salah satu ikan pelagis yang termasuk dalam family Scombridae. Ikan ini merupakan salah satu potensi sumberdaya ekonomis di Perairan Selat Sunda. Penelitian ini bertujuan untuk menganalisis aspek biologi reproduksi ikan tongkol (Euthynnus affinis) di perairan Selat Sunda. Pengambilan ikan contoh dilakukan pada bulan Mei-September 2016 di PPP Labuan, Banten, dan Juli-Agustus 2016 di PPP Lempasing, Lampung. Metode yang digunakan dalam pengambilan ikan contoh adalah penarikan contoh acak berlapis (PCAB). Rasio kelamin ikan tongkol jantan dan betina berdasarkan uji Chi square di PPP Labuan adalah 1,59 sedangkan di PPP Lempasing 1,40. Ikan tongkol di Selat Sunda menunjukkan pola pertumbuhan isometrik. Puncak pemijahan ikan tongkol diduga pada bulan Agustus dengan tipe pemijahan total spawaner. Fekunditas ikan tongkol berkisar 8 000-1 781 450 butir telur.
Keyword: Biologi reproduksi, ikan tongkol (Euthynnus affinis), Perairan Selat Sunda

Judul: Biologi Reproduksi Ikan Tongkol (Euthynnus Affinis Cantor, 1849) Di Perairan Selat Sunda
Abstrak: Ikan tongkol (Euthynnus affinis) merupakan salah satu potensi sumberdaya ikan ekonomis yang ada di perairan Selat Sunda. Penelitian ini dilakukan dari bulan April sampai Agustus 2015 di PPP Labuan, Banten. Ikan tongkol yang diukur selama penelitian berjumlah 746 ekor. Hubungan panjang bobot ikan tongkol diperoleh dengan persamaan W= 0,0038L3,2131 serta menunjukkan nilai R2 sebesar 97%. Pola pertumbuhan adalah allometrik positif, artinya pertumbuhan bobot lebih dominan dibandingkan pertumbuhan panjang. Rata-rata faktor kondisi ikan tongkol betina yaitu 1,0972 sedangkan ikan tongkol jantan yaitu 1,1203. Hal tersebut menunjukkan bahwa badan ikan tersebut berbentuk kurang pipih. Jumlah telur berkisar dari 17815 sampai 560793 butir telur. Ukuran pertama kali matang gonad sebesar 205-210 mm (betina) dan 403-410 mm (jantan). Periode pemijahan terjadi pada bulan Juli sampai Agustus dengan tipe pemijahan total spawner.
Keyword: biologi reproduksi, ikan tongkol (Euthynnus affinis), selat sunda

Judul: Glucose biosensor using a glucose dehydrogenase flavin adenine dinucleotide electrochemically immobilized on zeolite nanoparticles
Abstrak: A glucose biosensor was developed to measure blood glucose levels. The performance of these new glucose biosensors was continuously improved, producing better performance and stability. The technique selection and immobilization matrix are key factors for biosensor development, so that the prospecting of materials that can be used as a matrix for supporting enzyme, continue to be explore. The purpose of this study was to determine the activity and stability of the enzyme glucose dehydrogenase (GDH) that were immobilized on zeolite nanoparticles (NPZ) and determine the kinetic parameters and analytical performance by electrochemical methods. The resulting enzyme electrode with NPZ and enzyme electrode with zeolite A showed a high activity against the enzyme electrode glucose than without NPZ. The reaction kinetics of third electrodes of enzyme followed the Dixon equation. The 𝐼����𝑚����𝑎����𝑥����𝑎����𝑝����𝑝���� values for enzyme electrode without NPZ, with NPZ, and with zeolite A were 27.25 μA, 77.52 μA, and 48.54 μA, respectively. The 𝐾����𝑀����𝑎����𝑝����𝑝���� values for GDH enzyme that immobilized on the NPZ were 1.16 mM, 12.30 mM for GDH enzyme that immobilized on zeolite A and 0.95 mM for GDH enzyme immobilization without NPZ. The enzyme electrode without NPZ, with NPZ, and with zeolite A also showed a high sensitivity with value for the sensitivity were 0.58 μA mM-1, 0.81 μA mM-1, and 2.51 μA mM-1, respectively. The third enzyme electrodes showed different linear area with range for the enzyme electrode without NPZ, with NPZ and with zeolite A were 1.00-15.00 mM, 2.00-20.00 mM, and 0.06-10.00 mM, respectively. The blood glucose level of normal person ranged from 4 to 6 mM, so that the enzyme electrode with NPZ and without NPZ are suitable for use in the determination of the concentration of blood glucose. While the enzyme electrode with zeolite A has a smaller range so it is more suitable to use in the determination of glucose concentration in the foods or beverages. The enzyme electrode with NPZ and the enzyme electrode with zeolite A showed a good accuracy with relative error values were 3.84% and3.48%, respectively. Repeatability measurements also showed a good precission results with relative standard deviation values (%RSD) for the enzyme electrode with NPZ and enzyme electrode with zeolite A were 3.83% and 3.16%, respectively. By combining two immobilization techniques, physical adsorption on zeolite and entrapment on carbon paste, high enzymatic activity, good accuracy, and repeatability was attained. The enzyme electrode with NPZ and the enzyme electrode with zeolite A demonstrated a good electrochemical response toward glucose, allowing it to detect blood glucose levels and glucose levels in foods and beverages.
Keyword: glucose biosensor, immobilization, zeolite