Judul: Potensi Antioksidan Ekstrak Nanopartikel Kulit Kayu Mahoni Pada Tikus Dengan Prakondisi Diet Kaya Lipid
Abstrak: The aim of this research is to explore the antioxidant potency of nanoparticles of mahogany bark extracts in vivo. Thirty five rats were divided into three groups: normal rats (5), nanoparticle extracts- and crude extracts-treated rats (15 rats for each groups). Nanoparticle extracts- and crude extratcs- treated rats were preconditioned with high-lipid diet for 12 weeks. The research period was extended for 15 weeks hence the rats were all old animals (41 weeks old). Crude extracts and nanoparticles extracts groups were gavaged orally with dose of 300 mg/Kg BW. Lipid peroxide of blood serum was analyzed with thiobarbituric acid method (TBA) using spectrophotometer at 553 nm. Antioxidant potency of nanoparticles extracts of mahogany’s bark is showed by 44% reduction of rat’s blood lipid peroxide whereas the crude extracts only reduce 35%.
Keyword: nanoparticles, mahogany bark, antioxidant

Judul: Peroksidasi Lipid pada Tikus Hiperkolesterolemia selama Pemberian Ekstrak Kulit Batang Mahoni (Swietenia macrophylla)
Abstrak: Mahogany’s bark is known as wood industrial waste that contains potential secondary metabolites. However, its potency as an antioxidant, especially in rats which are subjected to hypercholesterolemic treatment, has not been carried out. The aim of this study was to test the effect of mahogany’s water extract consumption on the concentration of lipid peroxides in hypercholesterolemic rats. Thirty five male rats were divided into 5 groups (n=7) namely normal group fed with standard rat chow, hypercholesterolemic group (HK) fed with cholesterol chow (1,5%) and PTU (0,5 mg/KgBW), lovastatin group (HK+lovastatin 0,2857 mg/KgBW), E1 group (HK+ mahogany’s extract 4,2 mg/KgBW), and E2 group (HK+mahogany’s extract 21 mg/KgBW). Experiments were carried out for 8 consecutive weeks. The concentration of lipid peroxides in blood were measured with thiobarbituric acid assay at week 0, 2, 4, 6, and 8 using spectrophotometer. Cholesterol chow (0.86%) and PTU increased the lipid peroxides concentration of HK group by 20.92% compared to the normal group (3.380±0.436 nmol/mL). However, it is not statistically significant (p=0.239). The lipid peroxides concentration in E1 and E2 weren’t increased and relatively similar to normal group at concentration of 2.353±0.196 nmol/mL, 2.786±0.256 nmol/mL, and 2.673±0.279 nmol/mL, respectively. Although it is not statistically significant, both doses of extracts tend to prevent the lipid peroxidation in the rat’s blood.
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Judul: Identifikasi Kebutuhan Informasi Iklim pada Sektor Pertanian Menggunakan Model Subseasonal To Seasonal (S2S).
Abstrak: Informasi tentang prediksi curah hujan pada skala Subseasonal to Seasonal (S2S) dapat berguna sebagai dasar untuk pengambilan keputusan di berbagai sektor, termasuk sektor pertanian, oleh karena itu diperlukan sistem informasi iklim yang dapat dipahami oleh petani. Model Subseasonal to Seasonal (S2S) adalah model baru dan masih dalam tahap pengembangan sistem. Model prediksi S2S dapat mewakili kesenjangan prediksi yang berada pada rentang data harian dan musiman. Dengan adanya sistem yang dapat dipahami oleh petani, mereka dapat melakukan adaptasi yang dapat mengurangi kerugian akibat perubahan iklim. Kebutuhan petani akan informasi iklim cukup besar tetapi akses ke informasi prediksi curah hujan masih sulit. Salah satu upaya dalam meningkatkan performa dan akurasi prediksi yaitu dengan menjalankan beberapa model secara berulang-ulang sehingga menghasilkan tumpukan kemungkinan yang disebut sebagai ensemble. Model sistem prediksi ensemble ini mengkombinasikan model sistem prediksi tunggal dari lima penyedia data yang berbeda. Luaran ECMWF dan NCEP memiliki prediksi yang cukup baik karena pada data observasinya masih berada pada rentang maksimum dan minimum model sistem prediksi dan pada beberapa kejadian ekstrim tidak dapat ditunjukkan oleh luaran model sistem prediksi ensemble.
Keyword: Curah hujan, Ensemble, Subseasonal to Seasonal (S2S), Sistem informasi iklim