Judul: Modifikasi Pati Sagu Sebagai Bahan Baku Perekat Bubuk
Abstrak: Adhesive products used nowadays are mostly produced from synthetic materials that can pose adverse health effect to human. Natural materials like sago starch are predicted to have adhesion strength, therefore they might be potential to substitute synthetic materials. This research was intended to develop adhesive powder using dextrin derived from modified sago starch as a raw material. The expected outputs of this research were information about the characteristic of adhesive solution, application of the adhesive powder, and comparison of adhesion power of various adhesive strength. Three dextrin products (white, yellow and British Gum dextrin) utilized as raw materials for adhesive are chemically modified through dry heating at 90 ⁰C with the addition of HCl 0.1 N as the catalyst. The dextrins were analyzed for their characteristics, processed into solution and then the quality of the solution was evaluated. Furthermore, the dextrin solution was dried into powder and formulated so that in this application stage, the best adhesive powder, determined by its adhesion strength were obtained. The findings suggested that characteristics of the dextrin and quality of the adhesive reached the established tolerance limit. The best adhesive solution was derived from white dextrin rested for 10 minutes with adhesion strength of 10.58 kg/cm2. In the application stage, the best result for adhesive powder with the previously set formula, which was soaking method with powder to water ratio of 50:50, was obtained from white dextrin with adhesion strength of 10.50 kg/cm2.
Keyword: Bogor Agricultural University (IPB), adhesion strength, adhesive powder, adhesive, dextrin, sago starch

Judul: Produksi Pati Asetat dengan Menggunakan Pati Sagu Nanokristalin
Abstrak: Native sago starch has limited application when it is used as an active ingredient or drug carrier matrix because it is not acid resistance, high digestibility, and low solubility. It inhibits its function as a protector so that the active ingredient does not reach its target. Acetylated nanocrystallinestarch is a modified starch that can improve the characteristic of starch produced through a lintnerized process, precipitation with ethanol, and substituted with acetate anhydride. This study aims to improve the starch and modified starch performance as a drug carrier matrix in the form of acetylated starch. Three types of sago starch used are native starch, crystalline starch, and nanocrystalline-starch acetylated by using acetate anhydride with 3 and 6% concentration. In general, native sago starch is easier to be acetylated compared to crystalline starch and nanocrystalline starch. The result shows that the effect of acetylation increases the solubility and swelling power, but decreasing the water absorption, oil absorption, and starch digestibility. The concentration of acetate anhydride affects the solubility, % acetyl, and substitution degree. The increasing of acetate hydride concentration from 3% to 6% causes the increasing of % acetyl from 0.05-0.53%, substitution degree from 0.01-0.02 point, and product solubility up to 7%.
Keyword: Bogor Agricultural University (IPB), nanocrystalline starch, crystalline starch, sago starch, acetylation

Judul: Cycle Hamilton pada Graf Lengkap, Graf Regular, dan Graf 2-Connected 4-Regular Berorder Kurang dari Sepuluh
Abstrak: Suatu graf disebut graf Hamilton apabila graf tersebut memuat cycle Hamilton, yaitu cycle yang melewati setiap vertex tepat satu kali. Menentukan keberadaan cycle Hamilton pada suatu graf dapat menggunakan syarat cukup yang berupa teorema-teorema yang telah diperkenalkan sejak tahun 1950-an. Beberapa syarat cukup yang dibahas dalam karya ilmiah ini adalah syarat cukup yang berhubungan dengan graf lengkap dan graf regular. Suatu graf lengkap berorder 𝑛������ ≥ 3 dan graf r-regular berorder 𝑛������ ≤ 2𝑟������ + 1 merupakan graf Hamilton, Karena kedua graf tersebut memuat cycle Hamilton. Selanjutnya, syarat cukup tersebut digunakan untuk menentukan keberadaan cycle Hamilton pada graf 2-connected 4- regular berorder kurang dari 10.
Keyword: graf Hamilton, graf regular, graf lengkap, graf 2-connected 4-regular