Judul: Kandungan Fenolik dan Aktivitas Antioksidan Ekstrak Daun Gandarusa Hasil Optimasi Pelarut dengan Metode Sonikasi
Abstrak: Gandarusa (Justicia gendarussa Burm. f.) merupakan tanaman obat yang memiliki senyawa antioksidan untuk menangkal radikal bebas karena adanya kandungan metabolit sekunder seperti senyawa fenolik. Kandungan fenolik yang terekstrak serta nilai aktivitas antioksidan dapat dipengaruhi oleh pemakaian pelarut ekstraksi. Penelitian ini bertujuan menentukan pelarut terbaik antara air, etanol, dan asam asetat serta kombinasi ketiganya untuk ekstraksi daun tanaman gandarusa menggunakan metode sonikasi terhadap kadar total fenolik serta aktivitas antioksidan (metode DPPH dan FRAP) secara in vitro. Hasil penelitian menunjukkan bahwa nilai verifikasi yang diperoleh terhadap kadar total fenolik dan aktivitas antioksidan tidak berbeda jauh dengan nilai prediksinya dari software Design-Expert metode simplex lattice design (SLD), yaitu sebesar 3,257 mg GAE/g bobot kering pada kadar total fenolik, 0,182 µmol TE/g bobot kering pada aktivitas antioksidan metode DPPH, dan 8,117 µmol TE/g bobot kering pada aktivitas antioksidan metode FRAP dengan nilai desirability sebesar 0,621. Hal ini dilihat dari nilai signifikansi (p-value) pada kadar total fenolik dan aktivitas antioksidan yang menunjukkan lebih besar dari 0,05., Gendarussa (Justicia gendarussa Burm. f.) is a medicinal plant that has antioxidant compounds to counteract free radicals due to the content of secondary metabolites such as phenolic compounds. The extracted phenolic content and antioxidant activity value can be affected by the use of extraction solvent. This study aimed to determine the best solvent between water, ethanol, and acetic acid and their combination for extracting the leaves of the gendarussa plant using the sonication method on total phenolic content and antioxidant activity (DPPH and FRAP methods) in vitro. The results showed that the verification value obtained for total phenolic content and antioxidant activity did not differ much from the predicted values from Design-Expert software simplex lattice design (SLD) method, which was 3.257 mg GAE/g dry weight on total phenolic content, 0.182 µmol TE/g dry weight on antioxidant activity of DPPH method, and 8.117 µmol TE/g dry weight on antioxidant activity of FRAP method with a desirability value of 0.621. This can be seen from the significance value (p-value) on total phenolic content and antioxidant activity which showed greater than 0.05.
Keyword: antioxidant activity, DPPH, FRAP, gendarussa, phenolic

Judul: Variasi Aksesi terhadap Total Fenolik, Flavonoid serta Aktivitas Antioksidan Daun Gandarusa Asal Indonesia
Abstrak: Gandarusa (Justicia gendarussa Burm. f.) merupakan tanaman obat yang memiliki kandungan metabolit sekunder sebagai antioksidan. Produksi metabolit sekunder tanaman dipengaruhi oleh banyak faktor salah satunya variasi aksesi. Penelitian ini bertujuan memperoleh aksesi terbaik gandarusa yang menghasilkan metabolit sekunder dan aktivitas antioksidan tertinggi. Ekstrak etil asetat daun gandarusa diukur kadar total fenoliknya dengan metode Folin-Ciocalteu, kadar total flavonoid dengan metode aluminium klorida, serta aktivitas antioksidan dengan metode FRAP (Ferric Reducing Antioxidant Power) dan DPPH (1,1-diphenyl-2-picrylhydrazyl). Aksesi Langkat menghasilkan kadar total fenolik tertinggi sedangkan aksesi Malang menghasilkan kadar total flavonoid tertinggi yang berturut-turut sebesar 12,048 mg GAE g-1 bobot kering dan 17,043 mg QE g-1 bobot kering. Aksesi Bekasi menghasilkan aktivitas antioksidan FRAP tertinggi sedangkan aksesi Langkat menghasilkan aktivitas antioksidan DPPH tertinggi dengan nilai berturut-turut 16,669 dan 0,257 μmol TE g-1 bobot kering. Adapun korelasi antar variabel tidak menunjukkan hasil yang signifikan., Gandarusa (Justicia gendarussa Burm. f.) is a medicinal plant that contains secondary metabolites as antioxidants. The production of secondary metabolites of plants is influenced by many factors, one of which is the variation in accession. This study aimed to obtain the best accession of gandarusa which produces secondary metabolites and the highest antioxidant activity. Ethyl acetate extract of gandarusa leaves measured its total phenolic levels by the Folin-Ciocalteu method, total flavonoid levels with the aluminum chloride method, as well as antioxidant activity with the FRAP and DPPH methods. The Langkat accession produced the highest total phenolic levels while the Malang accession produced the highest total flavonoid levels which were successively 12,048 mg GAE g-1 dry weight and 17,043 mg QE g-1 dry weight. The Bekasi accession produced the highest FRAP antioxidant activity while the Langkat accession produced the highest DPPH antioxidant activity with successive values of 16.669 and 0.257 μmol TE g-1 dry weight. As for the correlation between variables, it does not show any significant results.
Keyword: accession, antioxidant, flavonoid, Justicia gendarussa, phenolic

Judul: Asymptotic Distribution of Estimator for the Intensity Function of a Doubly Periodic Poisson Process
Abstrak: In this manuscript, estimation of the intensity function of a doubly periodic Poisson process is discussed. It is assumed that only a single realization of the Poisson process is observed in a bounded window [0,n]. It is also assumed that the period of the intensity function is known. The rate of consistency and asymptotic normality of the estimator are formulated. Finally, a confidence interval for the local intensity function is also formulated.
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