Judul: Pemrofilan Metabolit dan Sifat Antioksidan Ekstrak Bakau (Xylocarpus granatum) Menggunakan Kromatografi Gas-Spektrometri Massa.
Abstrak: Karakteristik aktivitas hayati dari bakau Xylocarpus granatum sebagai bahan obat ditentukan oleh kandungan metabolitnya. Penelitian ini bertujuan mengidentifikasi profil metabolit dari ekstrak tumbuhan tersebut dan memprediksi metabolit yang berperan aktif sebagai antioksidan menggunakan pendekatan metabolomik berbasis GC-MS (kromatografi gas-spektrometri massa). Sampel diambil dari 6 bagian tanaman, yaitu biji, batang, kulit buah, daging buah, daun, dan ranting. Data kromatogram GC-MS diolah menggunakan MSDIAL untuk mengidentifikasi metabolit. Senyawa yang berhasil diidentifikasi dan dikonfirmasi sebanyak 153 senyawa. Dari hasil pemrofilan diperoleh sebanyak 15 senyawa yang diduga antioksidan, yang sebagian besar merupakan golongan fenolik dan polifenol. Senyawa antioksidan yang diduga potensial karena memiliki kadar terbanyak ialah, epicatechin dan epigallocatechin yang dominan terdapat pada bagian batang. Analisis komponen utama mengelompokan setiap bagian tanaman menjadi 3 kelompok berdasarkan komposisi metabolitnya: kelompok 1 (batang, kulit buah, dan ranting), kelompok 2 (biji dan daging buah), dan kelompok 3 (daun).
Keyword: antioksidan, bakau, GC-MS, metabolit, Xylocarpus granatum

Judul: Optimisasi Ekstraksi Batang Xylocarpus granatum sebagai Antioksidan dan Antiglikasi.
Abstrak: Xylocarpus granatum merupakan tumbuhan Indonesia yang mempunyai senyawa bioaktif fenolik dan aktivitas antioksidan yang tinggi pada bagian batang. Tujuan penelitian ini adalah menentukan kondisi optimum ekstraksi maserasi sebagai antioksidan dan antiglikasi batang X. granatum menggunakan metode permukaan respons. Kondisi optimum ekstraksi maserasi dipengaruhi oleh variabel ekstraksi (konsentrasi, nisbah sampel/pelarut, waktu ekstraksi) terhadap respons yang dievaluasi. Kondisi optimum ekstraksi diprediksi akan dicapai saat konsentrasi 52.25 %, waktu ekstraksi 15.92 jam, nisbah sampel/pelarut (1 g/9 mL) dengan rendemen, total fenolik, flavonoid, daya hambat pada 2,2’-diphenylpicryl hydrazyl, kapasitas pada 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid), dan daya hambat antiglikasi, masing-masing 12.81 %, 1.95 mg asam galat/g ekstrak, 62.33 μg kuersetin/g ekstrak, 44.11 %, 0.71 TEAC, dan 112.33 %. Pengoptimuman kondisi ekstraksi menunjukkan bahwa variabel ekstraksi berpengaruh signifikan terhadap respons, sehingga kondisi optimum tersebut dapat menghemat waktu ekstraksi, ekonomis, dan menghasilkan bioaktivitas tinggi.
Keyword: ABTS, antiglikasi, batang Xylocarous granatum, DPPH

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