Judul: Aktivitas Antioksidan dan Pemurnian Ekstrak Metanol Buah Ceremai (Phyllanthus acidus (L.) Skeel).
Abstrak: Stres oksidatif akibat radikal bebas merupakan penyebab banyak penyakit yang terjadi saat ini seperti inflamasi, penyakit kardiovaskular, kanker, dan penyakit gangguan syaraf. Buah ceremai (Phyllanthus acidus (L.) Skeel) merupakan salah satu buah yang memiliki potensi sebagai bahan antioksidan, sehingga perlu diuji aktivitasnya. Ekstrak metanol buah ceremai dimurnikan dengan menggunakan pelarut n-heksana, diklorometana, etil asetat, dan air lalu diuji aktivitas antioksidannya dengan metode DPPH. Kemurnian fraksi antioksidan potensial diuji dengan KCKT. Fraksi diklorometana memiliki aktivitas antioksidan paling kuat dengan nilai IC50 sebesar 85.548 μg/mL. Secara statistik, aktivitas antioksidan ekstrak metanol dan fraksi etil asetat tidak berbeda nyata dengan fraksi diklorometana dengan nilai IC50 sebesar 106.908 μg/mL dan 102.450 μg/mL (p<0.05). Kromatogram hasil analisis KCKT menunjukkan fraksi diklorometana masih merupakan campuran dari beberapa senyawa.
Keyword: buah ceremai, fraksinasi, antioksidan, DPPH, KCKT

Judul: Potensi Antioksidan dan Sitotoksisitas Ekstrak Buah Ceremai (Phyllanthus acidus L.)
Abstrak: Ceremai is an indigenous plant from India, belongs to Euphorbiaceae family. Ceremai plnat not only be used as an ornamental plant but can also be used as a herbal supplement. Ceremai Plants reported to have efficacy as a hepatoprotective, antibacterial, antifungal, antioxidant potency is not known yet. The purpose of this study to prove the antioxidant activity and cytotoxicity of fruit Ceremai. Ceremai was extracted by maceration using 70% ethanol, 30% ethanol, and water as solvents. Results were determined by antioxidant activity using of 2,2-diphenyl-1-pikrilhidrazil (DPPH) and its cytotoxicity (biological potency) was determined by Brine Shrimp Lethality Test (BSLT) method. IC50 values were 26.06 ppm, 72.39 ppm, and 62, 17 ppm for water, 30% ethanol and 70% ethanol exstract respectively. LC50 values were produced from three extracts water, ethanol 30%, and 70% ethanol, they were 473.26 ppm, 486.78 ppm, 618.55 ppm. Water extract is the best antioxidant activity compared with 30% ethanol extract and 70% ethanol. However, ceremai fresh fruit extracts are not good for human consumption herbal supplements because it is toxic.
Keyword: 

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