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.
Keyword: 

Judul: Evaluation of Pine Pollen Extract Dietary Supplementation on Masculinization and Reproduction Performance of Guppy (Poecilia reticulata)
Abstrak: Freshwater ornamental fish potential in Indonesia continues to increase, mainly male guppy (Poecilia reticulata) due to more beautiful color than female fish and more expensive price, which needs an effort to increase male percentage. Masculinization using androgenic synthetic hormone such as 17α-methyltestosterone is the most common way to increase total male fish produced. However, this hormone has several problems, namely high-cost import material and is thought to have a negative impact for the environment. Pine pollen (PP) is a highly potential material for organic androgenic source containing phytohormone or phytoandrogenic hormone. The aim of this study was to evaluate dietary supplementation of pine pollen extract fed during pregnant broodstock, larvae, and broodstock candidate phase on masculinization and reproduction performance of guppy fish. This study contained three steps, namely SSP extract dietary supplementation during pregnant broodtsock, larvae, and broodstock candidate phases. First step study was performed by evaluating the PP extract dietary supplementation in pregnant broodstock on the breed male sex ratio produced. This study used 5 treatments and 3 replications as each treatment unit was filled with 1 pregnant broodstock at 0.8-1 g broodstock-1 weight and 3.5-4.5 cm length. Treatments used were control (K), 1 mg kg-1 feed 17α-methyltestosterone (MT), 10 mg kg-1 feed SSP extract (SSP10), 50 mg kg-1 feed PP extract (SSP50), and 250 mg kg-1 feed SSP extract (SSP250). The feed available for pregnant broodstock was fed 3 times a day for 15 days at satiation. Parameters identified in this study were first- (B1) and second-born (B2) male sex ratios, B1 and B2 survival rates, broodstock testosterone hormone concentration on B1, broodstock estradiol level on B1, gonadosomatic index (GSI) on B1, hepatosomatic index (HSI) on B1, B1 and B2 birth difference, number of larvae produced by each broodstock, and testis and ovarium histology on B1 and B2. In the B1, the study results showed that the SSP250 treatment produced the highest male sex ratio at 66.40%, and had insignificant difference on survival rate (P>0.05). In the B2, the male sex ratio in control and PP treatments was insignificantly different. In the B1 and B2, the MT treatment obtained the highest male sex ratio compared to other treatments (P<0.05). The 17α-methyltestosterone residue still likely remained on 1-month after treatments were terminated. This condition induced the ongoing masculinization in the B2. The supplementation of SSP extract and MT certainly improve the plasma testosterone content either in broodstock or larvae. The first study step concludes that the dietary supplementation of SSP extract can increase the male sex ratio of guppy fish at 32.6% with 50 mg kg-1 feed as the optimal dose. The second study step was performed to evaluate the dietary supplementation of SSP extract in larvae on male sex ratio. This study contained 5 treatments and 3 replications filled with 20 0-3 days after birth larvae. Treatments applied were similar to the first study step. Feeding was performed at satiation 3 times a day for 15 days. Parameters identified were male sex ratio, survival rate, GSI, HSI, and testis and ovarium histology. The study results showed that SSP extract supplementation
Keyword: masculinization, pine pollen, Poecilia reticulata, reproduction performance, 17α-methyltestosterone

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