Judul: Profil Flavonoid, Tanin, dan Alkaloid dari Ekstrak Daun Sirih Merah (Piper crocatum)
Abstrak: Piper crocatum is Indonesia’s medicinal plant that has been proven to have anti-hyperglycemic, antioxidative, and anticancer activities. Hence, the aim of this study was to determine and analyze flavonoid, tannin, and alkaloid profiles of 30 % ethanol and water extracts of Piper crocatum leaves. Flavonoid, tannin, and alkaloid profiles were measured using spectrophotometry, titrimetry, gravimetry and LC-MS techniques. Phytochemical identification proved that both of extracts contain flanovoids, tannins, and alkaloids. Measurement of flavonoids quantitatively showed that the highest value was found in ethanol 30 % extract, 6.09 ± 0.26 mg QE/g. The highest quantitative tannin and alkaloid present in the water extract with a value of 3.97 ± 0.08 mg/g and 543.75 ± 3.17 mg/g. LC-MS analyze, the highest flavonoid compounds expected in water extract. The highest tannin and alkaloid compounds were expected in ethanol 30 % extract.
Keyword: tannins., Piper crocatum, flavonoids, alkaloids

Judul: Aktivitas Antioksidan, Total Tanin Ekstrak dan Fraksi Daun Sirih Merah (Piper crocatum) dan Identifikasi dengan LC-MS.
Abstrak: Sirih merah (Piper crocatum) merupakan salah satu tanaman yang dapat dijadikan sebagai sumber antioksidan yang memiliki potensial untuk mencegah berbagai jenis penyakit. Penelitian ini bertujuan menentukan kadar total tanin dan aktivitas antioksidan tertinggi dari ekstrak dan fraksi aktif daun sirih merah serta mengidentifikasi senyawa aktif yang yang berperan sebagai antioksidan. Ekstraksi dilakukan dengan cara maserasi menggunakan etanol 70%, selanjutnya ekstrak kasar difraksinasi menggunakan tiga pelarut berdasarkan tingkat kepolarannya, yaitu n-heksana, etil asetat, dan air. Uji total tanin dilakukan menggunakan metode permanganometri. Uji antioksidan dilakukan dengan metode CUPRAC (Cupric Ion Reducing Antioxidant Capacity) dan untuk identifikasi sampel yang memiliki senyawa antioksidan teraktif menggunakan LC-MS (Liquid Chromatography Mass Spectrometry). Berdasarkan hasil penelitian, fraksi n-heksan memiliki total tanin dan aktivitas antioksidan tertinggi dengan nilai 9.8 mg/g dan 31.9 μmol troloks/g ekstrak. Hasil analisis LC-MS menunjukkan terdapat tiga belas senyawa yang teridentifikasi di dalam fraksi n-heksan daun sirih merah.
Keyword: antioksidan, CUPRAC, LC-MS, tanin, sirih merah

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