Judul: Karakterisasi dan Ekstraksi Rumput Laut Gracilaria sp. Asal Tambak Berbeda di Kabupaten Karawang
Abstrak: Gracilaria sp. merupakan salah satu jenis rumput laut merah yang banyak dibudidayakan di perairan Indonesia, terutama Kabupaten Karawang, Provinsi Jawa Barat. Gracilaria sp. diketahui memiliki senyawa bioaktif diantaranya yaitu kandungan total fenol serta fitokimia. Penelitian ini bertujuan membedakan kandungan fitokimia, total fenol dan logam berat pada rumput laut kering Gracilaria sp. berdasarkan perbedaan lokasi panen. Penelitian ini menggunakan rumput laut Gracilaria sp. di tambak yang berlokasi di Desa Sedari (A), Desa Saca (B), dan Desa Tambaksari (C). Rancangan percobaan yang digunakan dalam penelitian ini adalah Rancangan Acak Lengkap satu faktorial dan uji lanjut LSD. Kandungan logam berat Pb rumput laut kering Gracilaria sp. lokasi A dan C belum memenuhi SNI 2690 tahun 2018 tentang Rumput Laut Kering. Hasil uji ekstrak etanol kandungan aktif rumput laut Gracilaria sp. diperoleh hasil fitokimia pada seluruh lokasi cukup seragam, diantaranya terdeteksi alkaloid, fenol, flavonoid, dan saponin. Kandungan total fenol pada rumput laut berbeda nyata terhadap perbedaan lokasi panen dengan nilai total fenol sampel A, B, dan C berturut turut sebesar 610.33, 526.66, dan 657,66 mgGAE/g.
Keyword: Fitokimia, Gracilaria sp., Kandungan total fenol, Logam berat

Judul: Differences in the Characteristics of Agar Flour
Content of Gracilaria sp. from Karawang at different cultivation locations
Abstrak: Rumput laut Gracilaria sp. merupakan salah satu bahan baku yang umum digunakan dalam pembuatan agar-agar. Bentuk sediaan bahan baku yang dapat dihasilkan dari rumput laut Gracilaria sp. adalah tepung agar. Tepung agar pada penelitian ini dihasilkan melalui metode ekstraksi dari Rumput laut Gracilaria sp. hasil tambak budidaya yang berbeda didaerah Karawang, yaitu Neglasari, Tambaksari, dan Saca. Analisis tepung agar dilakukan untuk menentukan kualitas tepung dengan melihat parameter kualitas air, kualitas proksimat, kualitas agar dan Total Plate Count (TPC). Hasil parameter kualitas air antara lain nilai pH yang memiliki nilai berkisar 7,2 hingga 8,2. Salinitas yang memiliki nilai berkisar antara 17,7 - 23,7 ‰. Suhu berada pada 32,6 – 33,4 ?. Nilai kecerahan berkisar pada 26 – 54. Kadar fosfat berkisar 1,88 - 3,23 mg/L. Kadar nitrat 1,31 – 2,45 mg/L. Hasil parameter proksimat tepung agar Gracilaria sp.. antara lain kadar air berkisar 13,99 – 15,27 %. Kadar abu berkisar 3,29 – 3,68 %. Kadar protein berkisar 6,30 – 7,54 %. Kadar lemak berkisar 0,48 – 0,55. Serat kasar berkisar 4,02 - 5,95 %. Hasil parameter kualitas agar antara lain nilai rendemen berkisar 30,5 – 53,2 %. Kekuatan gel berkisar 245,4 – 328,4 g/cm2. Viskositas berkisar 13,4 – 23,5. Kadar sulfat berkisar 3,53 – 5,88 %. Analisis TPC memiliki nilai pada lokasi Neglasari sebesar 0,73 x 103 koloni/gram, lokasi tambaksari sebesar 1,10 x 103 koloni/gram, lokasi Saca sebesar 0,67 x 103 koloni/gram. Perlakuan terbaik yaitu tepung agar dari lokasi Neglasari dengan karakteristik total rendemen, kadar protein dan serat kasarnya yang paling tinggi, kadar air yang sesuai standar SNI, dan kekuatan gel yang sesuai dengan literatur., Seaweed Gracilaria sp. is one of the raw materials commonly used in making agar-agar. The dosage form of raw materials that can be produced from seaweed Gracilaria sp. is agar flour. Agar flour in this research was produced using an extraction method from Gracilaria sp. seaweed. the results of different cultivation ponds in the Karawang area, namely Neglasari, Tambaksari, and Saca. Agar flour analysis is carried out to determine the quality of the flour by looking at the parameters of water quality, proximate quality, agar quality and Total Plate Count (TPC). The results of water quality parameters included the pH value, which ranged from 7.2 to 8.2. The temperature was at 32.6 – 33.4 ?. Brightness values ranged from 26 to 54. Phosphate levels ranged from 1.88 to 3.23 mg/L. Nitrate levels ranged from 1.31 to 2.45 mg/L. Results of proximate parameters of Gracilaria sp. agar flour included water content ranging from 13.99 to 15.27%. Ash content ranged from 3.29 to 3.68%. Protein content ranged from 6.30 to 7.54%. Fat content ranged from 0.48 to 0.55%. Crude fiber ranged from 4.02 to 5.95%. The results of agar quality parameters included yield values ranging from 30.5 to 53.2%. Gel strength ranged from 245.4 to 328.4 g/cm². Viscosity ranged from 13.4 to 23.5. Sulfate levels ranged from 3.53 to 5.88%. TPC analysis had a value for the Neglasari location of 0.73 x 10³ CFU/g, the Tambaksari location of 1.10 x 10³ CFU/g, and the Saca location of 0.67 x 10³
Keyword: Ekstraksi, Kualitas, rumput laut, Agar, Gracilaria sp

Judul: A Continuous Vaccination Strategy in the SVIR Epidemic Model
Abstrak: Vaccination is conducted to minimize the spread of a disease. The vaccination is usually done several times within a fixed time interval. In the SVIR model, it is assumed that individuals do not get immediate immunity following a vaccination program. So according to process of vaccination on SVIR model, there are two strategies, i.e. the continuous vaccination strategy (CVS) and the pulse vaccination strategy (PVS). In this study, only the CVS strategy in epidemic model SVIR is considered. Results of the study indicate that dynamics of the CVS system depends on the basic reproductive number. If the basic reproductive number is less than one, then the disease-free fixed point is asymptotically stable. It means that the disease will eventually disappear from the population. Conversely, if the basic reproductive number is greater than one, then the endemic fixed point is asymptotically stable, which means that the disease will remain exist in the population. Simulation result shows that the vaccination would minimize the spread of disease by reducing the basic reproductive number. If the time for the vaccinated recipients to obtain the immunity, as well as a possibility of vaccinated recipients to be infected are neglected, then the disease will be eradicated. This condition is called an over-evaluating effect of vaccination.
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