Judul: IPB (Bogor Agricultural University)
Abstrak: Sea cucumber is one of marine species which has high economic values. So far, sea cucumber muscles have been consumed as a high protein source, whereas visceral organs still become wastes. Some researchers have found bioactive compounds in sea cucumber which are potential e.g. antibacterial, antifungal and high steroid hormone substance. Besides as approdisiach, steroid hormone can be used for hormonal sex reversal in aquaculture. This research was conducted to utilize steroid extract from sea cucumber visceral organs for sex reversal in the Guppy and find effective doses. Extraction of steroid from sea cucumber visceral organs was done by percolation technique. The existence of steroid was identified by Lieberman Burchard reagent while it’s concentration is analyzed by HPLC. Steroid extract for sex reversal was assayed to mature brood female Guppy in two techniques; orally technique which doses were 0, 200, 400 and 600 mg/kg feed and dipping technique which doses were 0, 1, 2 and 4 mg/l. Both of them were compared with synthetic hormone as positive control. Data were then analyzed by ANOVA and T test. Crude extract obtained from extraction was 86.384 g from 2.5 kg raw material, steroid extract was 0.762 g, and testosterone concentration was 0.527 μg/mg extract. In orally technique, the highest result was showed by treatment with dose 600 mg/kg where percentage of male was 61.11±9.62%, the number of offspring was 40±28, and survival rate was 99.05±1.65%. In dipping technique, the highest number of offspring was 37±16, showed by treatment with dose 1 mg/l. Treatment with 17 - methyltestosterone concludes that percentage of male was higher than treatment with natural steroid hormone. But, on the other hand, this synthetic hormone can have negative effects by causing fish embryo and fry died so that the number of offspring will be dropped off.
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Judul: Isolation, Characterisation and Biological Activity Test of Sea Cucumber Steroid Compound as Natural Aphrodisiac
Abstrak: Sea cucumber (Holothurian) is one of fisheries commodities which has a high economic value. Generally sea cucumber is traded in the dried form (bechede- mer). Bioactive of sea cucumber, commonly known as holothurin, has drawn attention because of its wide spectrum of biological effects namely antibacterial, antifungal, cytotoxic, haemolytic and anti-inflammation. One of holothurins, steroid compounds, as natural aphrodisiac have not been observed yet. Therefore, the aims of this study were (1) to isolate steroid compounds of sea cucumber and their contents, (2) to characterise the compounds, (3) to know biological activity of the compounds as aphrodisiac, and (4) to do experiment of nanofiltration membrane for initial purification of steroid compounds. Steroid compounds of Holothuria scabra have been originally isolated from Holothurian of Lampung waters using acetone as a solvent. Six steroid fractions were found through thin layer chromatography (TLC) and two fractions have been identified as cholesterol and testosterone with Rf 0.96 and 0.91, respectively. Initial purification used ceramic membrane with MWCO 1000 dalton for filtration process. To better understand biological activity of the steroid, day old chicken (DOC) was used as a test organism. Parameters observed were N absorption, body weight and cap, testes, cholesterol and testosterone concentrations of blood serum. The results clearly demonstrated that sea cucumber Holothuria scabra could be used as a source of aphrodisiac.
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Judul: Kombinasi algoritma sha 1 dan algoritma rsa untuk membentuk tanda tangan digital
Abstrak: Tanda tangan digital termasuk ke dalam teknik kriptografi yang memanfaatkan teknologi kunci publik (enkripsi asimetris). Tanda tangan digital dapat dibuat dengan mengkombinasikan teknik hashing (untuk membentuk message digest dari pesan asli) dan enkripsi asimetris (untuk membentuk kunci publik dan kunci privat). Teknik hashing yang digunakan adalah teknik rashing satu arah dengan menggunakan algoritma SHA 1, sedangkan algoritma RSA digunakan untuk enkripsi asimetris Tulisan ini bertujuan untuk mempelajari, menganalisis, dan mengimplementasikan pembentukan dan verifikasi tanda tangan digital menggunakan dua metode, yaitu dengan mengkombinasikan algoritma SHA 1 dan algoritma RSA dan dengan menggunakan algoritma RSA saja. Analisis yang dilakukan pada kedua algoritma ini meliputi analisis algoritma, dan analisis hasil implementasi. Analisis terhadap algoritma SHA | menunjukkan bahwa algoritma ini memiliki kompleksitas O(n) untuk kasus terburuk. Sedangkan untuk pembentukan kunci publik dan kunci privat dengan algoritma RSA diperlukan beberapa algoritma pendukung, yaitu algoritma Miller Rabin, Witness, Euclid, dan Extended Euclid. Semua algoritma pendukung tersebut memiliki kompleksitas waktu yang sama, yaitu O(k), dengan adalah panjang representasi bit bilangan bulat. Kompleksitas waktu yang didapatkan untuk proses pembentukan tanda tangan digital dengan kedua metode ini adalah sama yaitu O(nk). Untuk proses verifikasi, kompleksitas waktu yang didapatkan dengan menggunakan kombinasi dua algoritma adalah O(1 + k) dan untuk algoritma RSA adalah O(n + k). Pada proses pembentukan tanda tangan digital menggunakan kombinasi dua algoritma yang ditandatangani adalah message digest yang dihasilkan oleh algoritma SHA 1, sedangkan pada algoritma RSA yang ditandatangani adalah pesan itu sendiri. Dari hasil implementasi didapatkan untuk proses pembentukan tanda tangan digital menggunakan kombinasi dua algoritma lebih cepat dibandingkan dengan menggunakan algoritma RSA saja untuk file-file yang berukuran besar, dst
Keyword: Tnda Tangan Digital, Teknik Kriptografi, Enskripsi Asimetris