Judul: Aspek Biologi Reproduksi Ikan Lemuru (Sardinella longiceps C.V.) di Perairan Teluk Sibolga, Sumatera- Utara
Abstrak: Ikan lemuru (Sardinella longiceps C.V.) merupakan ikan ekonomis penting Saat ini informasi biologis ikan lemuru di perairan Sibolga belum ada. Informasi tersebut dibutuhkan untuk tujuan pengelolaan kegiatan perikanan di wilayah tersebut. Penelitian bertujuan untuk mengetahui aspek biologi reproduksi ikan lemuru (Sardinella longiceps C.V.).
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Judul: Studi tentang reproduksi ikan lamuru (Sardinella lemuru Bleeker, 1853) di Perairan Selat Alas Nusa Tenggara Barat
Abstrak: Perairan Selat Alas terletak di antara Pulau Lombok dan Sumbawa, Propinsi Nusa Tenggara Barat dengan luas sekitar 20542 km². Perairan tersebut merupakan suatu bentuk perairan yang relatif sempit dan dangkal dengan kedalaman rata-rata kurang dari 100 m, produktivitasnya tinggi karena terjadi proses air naik (upwelling), diperkirakan mulai dari bulan Mei sampai Nopember. Ikan Lemuru merupakan jenis ikan yang dominan tertangkap di perairan tersebut, produksinya berkisar antara 1380.7 18053 ton per tahun. Rataan per tahunnya sebesar 6395 ton (53%) dari produksi total dalam periode tahun 1984 - 1994, sedangkan rataan setiap bulannya sebesar 900 ton dalam peri- ode 1990 - 1994, dan kisaran bulanannya antara 0.3 94 ton. Fluktuasi hasil tangkapan ikan lemuru di perairan Selat Alas bervariasi dari tahun ke tahun. Oleh karena itu dalam penelitian ini pengkajian masalah dititikberatkan pada aspek- aspek reproduksi dan lingkungan perairan yang mempengaruhi pola reproduksi ikan lemuru. Pola reproduksi adalah segala aktivitas yang berkaitan dengan fungsi perkembangbiakan..dst
Keyword: Ikan Lamuru

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