Judul: Isolasi dan Identifikasi Senyawa Antibakteri Minyak Atsiri Daun Zodia (Evodia sp.)
Abstrak: Sejak pertama kali ditemukan hingga akhir abad 20, kemoterapi antimikroba telah berhasil menyembuhkan berbagai jenis penyakit infeksi. Masalah muncul pada saat terjadi resistensi bakteri. Meskipun berbagai jenis antibiotik baru ditemukan, muncul masalah baru berkaitan dengan resistensi terhadap berbaai jenis antibiotik Tumbuhan memghasilkan ribuan molekul yang berfungsi bagi tumbuhan itu sendiri maupun lingkungannya. Beberapa jenis komponen minyak atsiri menghasilkan aktivitas antibakteri. Penelitian ini bertujuan untuk menentukan potensi antibakteri minyak atsiri daun zodia, mengisolasi dan mengidentifikasi senyawa aktifnya.
Keyword: Antibacterial Activity, Essential oil, Toksisitas Minyak Atsiri

Judul: Eksplorasi Minyak Atsiri Sepuluh Spesies Famili Asteraceae dan Studi Antibakteri terhadap Staphylococcus aureus dan Escherichia coli.
Abstrak: Minyak atsiri yang diproduksi oleh tumbuhan aromatik memiliki aktivitas hayati di antaranya antibakteri. Penelitian ini bertujuan mendapatkan minyak atsiri dari bagian daun 10 spesies tumbuhan famili Asteraceae, studi literatur aktivitas minyak atsiri tersebut terhadap Staphylococcus aureus dan Escherichia coli serta menduga senyawa aktif antibakteri. Kesepuluh spesies menghasilkan minyak atsiri dengan rendemen terbesar oleh Ageratum conyzoides dan rendemen terkecil oleh Tagetes minuta. Sembilan minyak atsiri aktif terhadap kedua bakteri uji dengan kekuatan yang berbeda kecuali minyak atsiri Cosmos caudatus. Senyawa monoterpena yang aktif antibakteri ialah limonena, mirsena, dihidrotageton, dan α- pinena. Senyawa seskuiterpena yang aktif antibakteri ialah germakrena D, γ- kadinena, dan (Z)-γ-bisabolena. Senyawa lain yang aktif antibakteri, yaitu prekokena I dan prekokena II. Aktivitas antibakteri senyawa seskuiterpena lebih baik dibandingkan dengan monoterpena. Senyawa minyak atsiri dipengaruhi oleh tempat tumbuh, faktor geografis, adaptasi tumbuhan terhadap habitat, dan variasi genetik.
Keyword: antibakteri, Asteraceae, Escherichia coli, minyak atsiri, Staphylococcus aureus

Judul: The Construction of Greedy SVP LLL Algorithm
Abstrak: A lattice is a set of all integer linear combination of a set of linearly independent vectors in ℝ𝑛���. The independent vectors are called bases of lattice. Any lattice can be generated from many bases, and these bases have the same cardinality. In the lattice, the most fundamental and renowned problem is the Shortest Vector Problem (SVP). SVP is a tracking problem of the shortest nonzero vector in a lattice with equivalent bases. In two dimensions, SVP problem has resolved exactly by Gauss’ algorithm. When the lattice dimension is higher than two, A.K. Lenstra, H.W. Lenstra and L. Lovasz gave a LLL algorithm to compute approximation of nonzero shortest vector in the lattice. Reduced bases solution obtained from LLL algorithm still be an approximation and has polynomial running time of arbitrary dimension which large enough. In 1994, Schnoor and Euchner modified this LLL algorithm as a new variant which later was named deep insertion LLL algorithm. This algorithm is a modified version of the LLL algorithm to the terms of the exchange step to improve the accuracy of output of LLL reduced bases and applying it to the subset sum problem. The purpose of this research are: (1) Reconstruct the LLL algorithm and deep insertion LLL algorithm using a geometric approach. (2) Construct a greedy SVP LLL algorithm. (3) Implement the three algorithms in a symbolic programming language, and evaluate them experimentally. A bases ℬ=[𝐛���1,𝐛���2,…,𝐛���𝑛���] in ℝ𝑚��� is called reduced LLL with parameter 𝛿��� if satisfies: (a) |𝜇���𝑗���𝑖���|≤12, for every integer 𝑖���,𝑗��� with 1≤𝑖���<𝑗���<𝑛���. (b)𝛿���‖𝜋���𝑗���(𝐛���𝑗���)‖2≤‖𝜋���𝑗���(𝐛���𝑗���+1)‖2, for 𝑗���=1,2,…,𝑛���−1,where 𝛿��� is a reduced parameter of real numbers with 14<𝛿���<1. The first requirement is the reduced basis 𝛿��� must “nearly orthogonal” and in its computation case, this requirement can be reached out by using the Gram-Schmidt’s orthogonalization. While the second requirement is called exchange step, or used to called as Lovasz condition. By using both of these requirements, then they establish the LLL algorithm. Then, Schnoor and Euchner modify the LLL algorithm based on the requirements of the exchange step called the deep insertion LLL algorithm, where the exchange step is based on the comparison of the projected vector in orthogonal complement [𝐛���1,𝐛���2,…,𝐛���𝑘���−1]⊥ after j-th reduction. To construct greedy SVP LLL algorithm, the requirements of the exchange step is based on purely by comparing norm of lattice 𝐛���𝑗��� with norm lattice 𝐛���𝑖��� for 𝑖���=1,2,3…,𝑗���−1. The process of insertion reduced vector after the exchange step also has done greedily. Then, we calculate the number of arithmetic operation in greedy SVP LLL algorithm for further analysis. The result of our exprimentation for three algorithms on the certain matrix size shows that the running time of the three algorithms increases propotional to the size of the matrix. The result also shows that by using 𝛿���=34 for the LLL algorithm and the deep insertion LLL algorithm, and the greedy SVP LLL algorithm which is a new variant made by using no parameter of 𝛿���, outperform of the other of two previous algorithm in terms of speed with the same output.
Keyword: LLL algorithm, LLL deep insertion algorithm, greedy SVP LLL algorithm