Judul: Aktivitas Antioksidan Dan Potensi Hayati Dari Kombinasi Ekstrak Empat Jenis Tanaman Obat Indonesia
Abstrak: The crude ethanol extracts combination of four Indonesia medicinal plants namely Curcuma xanthorriza, Phyllanthus niruri, Andrographis paniculata, and Curcuma aeruginosa were examined for their antioxidant (radical scavenging) activity using 2,2-diphenyl-1-picrylhidrazyl (DPPH) free radical and biological activities or cytotoxicity using brine shrimp lethality test (BSLT). IC50 values for DPPH radical scavengeing activity ranged from 1.923 to 211.127 ppm, with extract combination of Curcuma xanthorriza and Curcuma aeruginosa (1:0:0:1) having the lowest value and therefore the most potent, and extract combination of Phyllanthus niruri, Andrographis paniculata, and Curcuma aeruginosa (0:1:1:1) having the highest value. LC50 values for BSLT ranged from 31.796 to 620.165 ppm, with extract combination of Curcuma xanthorriza, Phyllanthus niruri, Andrographis paniculata, and Curcuma aeruginosa (1:1:1:1) having lowest value and therefore the most potent, and extract of Curcuma aeruginosa (0:0:0:1) having the highest value. A positive correlation between antioxidant and biological activities of extract combination was obtained from combination (1:1:1:1), with antioxidant and biological or cytotoxicity values were 41.87 and 31.79 ppm, respectively.
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Judul: Pengukuran Aktivitas Antioksidan dengan Metode Cuprac, DPPH, dan Frap serta Korelasinya dengan Fenol dan Flavonoid pada Enam Tanaman
Abstrak: Oxidative stress is the imbalance condition between free radical and antioxidants that can cause oxidative damage in cell, tissues, organ, accelerates the aging process, and emergence of diseases. This study aims to determine the antioxidant capacity of 6 herbs, and the relationship between phenol and flavonoids content with their antioxidant activity and relationship between phenol and flavonoids content in the ethanol extract of some Indonesian herb, there are Orthosiphon stamineus, Sonchus avensis, Sida rhombifolia, Guazuma umifolia, Andrographis paniculata, and Parkia biglobosa. The measurement of antioxidant activity use 3 methods, that are CUPRAC (cupric ion reducing antioxidant capacity), DPPH (2,2-diphenyl-1-pickrylhidrazyl), and FRAP (ferric reducing antioxidant power). The research of the six herbs showed antioxidant activity. Statistic test from three method antioxidant showed that measurement antioxidant activity with CUPRAC, DPPH, and FRAP gave a significantly different result, but CUPRAC and FRAP give the same response of the six herbs. The phenol has no correlation with flavonoids content but have highly correlation with their antioxidant activity. Flavonoids have no correlation with antioxidant activity.
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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