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"ABSTRAKProduction biodiesel from non-edible vegetable oil is gaining attention and interst recently. In this tudy, jatropha curcas and calophyllum inophyllum were applied as non food feedstock for biodiesel production. Firally, the result of the investigation indicated that the optimization of jatropha curcas and calophyllum inophyllum have fuel properties quite comparable to diesel and thus may be explored for application in compression ignition engines."

"Pada penelitian ini telah dilakukan sintesis nanopartikel dan nanopartikel ZnO termodifikasi BiVO4 secara green synthesis menggunakan ekstrak daun nyamplung Calophyllum inophyllum yang mengandung alkaloid sebagai sumber basa lemah dan flavonoid, saponin, dan polifenol sebagai capping agent. Modifikasi nanopartikel ZnO dilakukan untuk meningkatkan aktivitas fotokatalitik nanopartikel ZnO dan memperluas jangkauan ke daerah sinar tampak dengan adanya penurunan nilai band gap. Hasil sintesis nanopartikel ZnO, nanopartikel BiVO4, dan nanokomposit ZnO-BiVO4 dikarakterisari menggunakan spektrofotometer UV-Vis, UV-Vis DRS, FTIR, PSA, dan SEM-EDX. Hasil karakterisasi spektrofotometer UV-Vis menunjukkan adanya puncak khas serapan absorpsi UV-Vis nanopartikel ZnO pada panjang gelombang maksimum 369 nm. Berdasarkan spektra XRD, nanopartikel ZnO memiliki struktur hexagonal wurtzite dan nanopartikel BiVO4 memiliki struktur monoclinic scheelite. Nilai band gap untuk nanopartikel ZnO, nanopartikel BiVO4, dan nanokomposit ZnO-BiVO4 berturut-turut yaitu 3,25 eV, 2,47 eV, dan 2,93 eV dengan distribusi ukuran rata-rata partikel berdasarkan karakterisasi PSA yaitu 32,4 nm, 96,0 nm, dan 96,0 nm. Berdasarkan hasil karakteri SEM, morfologi nanopartikel ZnO berbentuk spherical, nanopartikel BiVO4 berbentuk semi-spherical, dan ZnO-BiVO4 berbentuk semi-spherical yang masih beraglomerasi. Aktivitas fotokatalitik nanopartikel dan nanokomposit dilakukan pemodelan untuk mendegradasi senyawa zat warna malasit hijau dengan massa optimum katalis 1,0 mg dalam 25 mL malasit hijau dengan konsentrasi 5,0x10-6 M dan menghasilkan persentase degradasi malasit hijau menggunakan nanopartikel ZnO, nanopartikel BiVO4, dan nanokomposit ZnO-BiVO4 berturut-turut yaitu sebesar 82,34 , 65,90 , dan 94,74 selama 120 menit dibawah radiasi sinar tampak. Analisis LC-MS digunakan untuk mengetahui produk yang dihasilkan selama 120 menit proses fotodegradasi malasit hijau menggunakan nanokomposit ZnO-BiVO4.

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In this study, synthesis of nanoparticles and nanocomposites by green synthesis process using Calophyllum inophyllum leaf extract which containing alkaloids as weak base sources and flavonoids, saponins, and polyphenols as capping agent. Modification of ZnO nanoparticles using BiVO4 nanoparticles can enhance the photocatalytic activity of ZnO nanoparticles and can extend the range to visible light areas in the presence of decreased band gap value. The synthesis of ZnO nanoparticles, BiVO4 nanoparticles, and ZnO BiVO4 nanocomposites were characterized using UV Vis spectrophotometer, UV Vis DRS, FTIR, PSA, and SEM EDX. The result of UV Vis spectrophotometer characterization appears maximum wave length at 369 nm indicating the formation of ZnO nanoparticles. Based on the XRD spectrum the ZnO nanoparticles formed have a hexagonal wurtzite structure, and BiVO4 nanoparticles were monoclinic scheelite. The band gap values for ZnO nanoparticles, BiVO4 nanoparticles and ZnO BiVO4 nanocomposites were 3.25 eV, 2.47 eV, and 2.93 eV respectively with mean particle size distribution based on PSA characterization of 32.4 nm, 96.0 nm, and 96.0 nm. SEM analysis shows that morphology of ZnO nanoparticles is spherically shaped, BiVO4 nanoparticles is semi spherical, and ZnO BiVO4 is semi spherical were still agglomerated. Photocatalytic activity of nanoparticles and nanocomposites was modeled to degrade the malachite green compounds with optimum catalyst mass of 1,0 mg in 25 mL malachite green with concentration 5x10 6 M and percent degradation of malachite green for ZnO nanoparticles, BiVO4 nanoparticles and ZnO BiVO4 nanocomposites respectively of 82.34 , 65, 90 , and 94.74 for 120 minutes under visible light irradiation. The LC MS analysis was used to find out the compound which produced during 120 minutes photodegradation process of malachite green using ZnO BiVO4 nanocomposite."

"Permintaan energi global yang semakin tinggi, ditambah dengan dampak emisi gas rumah kaca yang berbahaya dari bahan bakar fosil, telah memicu pencarian sumber energi alternatif yang tidak bersaing dengan pasokan makanan. Penelitian ini melakukan perengkahan katalitik minyak nyamplung menjadi senyawa biohidrokarbon menggunakan katalis zeolit berbasis fly ash yang dimodifikasi. Katalis zeolite didapatkan dari preparasi fly-ash dengan metode pencucian asam (HCl) dan peleburan alkali (NaOH) yang diimpergnasi dengan kalsium oksida (CaO) dan nikel oksida (NiO) untuk meningkatkan kinerjanya. Variasi rasio campuran katalis 5% dan 10% CaO, serta 1-3% NiO, suhu 450-550◦C, dan rasio minyak terhadap katalis 0-20%wt. Hasil reaksi perengkahan berupa bio-oil dikarakterisasi dengan Gas Cromatography-Mass Spectroscopy (GCMS) dan Fourier Transform Infra-Red (FT-IR). Hasil preparasi katalis dikarakterisasi dengan X-ray diffraction (XRD), X-ray fluorescence (XRF), Scanning Electron Microscopy (SEM), dan Brunauer–Emmett–Teller (BET). Berdasarkan hasil penelitian, minyak nyamplung berhasil dikonversi menjadi senyawa biohidrokarbon dengan variasi katalis zeolite fly ash (ZFA) yang dimodifikasi dengan CaO dan NiO. Jenis katalis ZFA terimpregnasi 3% NiO (3%NiO/ZFA) pada suhu 550◦C dan rasio massa katalis terhadap minyak umpan 10%wt menghasilkan konversi terbesar 81,89%. Berdasarkan hasil GCMS, hasil selektivitas fraksi rantai gasoline (C5-C11) sebesar 27,14%. Karakteristik sifat fisik dari biohidrokarbonnya mendekati standar biodiesel dengan nilai densitas (717 kg/m3), viskositas kinematic (2,69 cSt,), dan angka RON (94).

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Increasing global energy demand and the harmful effects of greenhouse gas emissions from fossil fuels, has fuelled the search for alternative energy sources that don’t compete with food supplies. This study conducted the catalytic cracking of nyamplung oil into bio-hydrocarbon compounds using a modified fly ash-based zeolite catalyst. The zeolite catalyst was obtained from fly-ash preparation by acid washing (HCl) and alkali melting (NaOH) impregnated with calcium oxide (CaO) and nickel oxide (NiO) to improve its performance. Variation of catalyst mixture of 5% and 10% CaO, with 1-3% NiO, temperature 450-550◦C, and ratio of oil to catalyst 0-20% wt. The results of the cracking reaction in the form of bio-oil were characterized by Gas Chromatography-Mass Spectroscopy (GCMS) and Fourier Transform Infra-Red (FT-IR). The catalyst preparation results were characterized by X-ray diffraction (XRD), X-ray fluorescence (XRF), Scanning Electron Microscopy (SEM), and Brunauer–Emmett–Teller (BET). Based on the results of the research, nyamplung oil was successfully converted into bio-hydrocarbon compounds using a variety of zeolite fly ash (ZFA) catalysts modified with CaO and NiO. Catalyst type ZFA impregnated with 3% NiO (3%NiO/ZFA) at 550◦C and mass ratio of catalyst to feed oil of 10%wt produced the biggest conversion of 81,89%. Based on the GCMS results, the selectivity of the gasoline chain fraction (C5-C11) was 27,14%. The physical properties of the bio-hydrocarbons are close to those of biodiesel with a density value (717 kg/m3), kinematic viscosity (2,69 cSt,), and RON number (94)."

"Produksi berlebih dan kurangnya ekskresi asam urat dalam tubuh dapat menyebabkan hiperurisemia. Xantin oksidase merupakan enzim yang berperan dalam mengkatalisis oksidasi hipoxantin dan xantin menjadi asam urat.Tujuan penelitian ini untuk mengetahui tanaman obat yang memiliki aktivitas penghambatan enzim xantin oksidase serta identifikasi golongan kandungan kimianya. Metode yang digunakan menguji aktivitas penghambatan enzim xantin oksidase adalah Continous Spectrophotometric Rate Determination. Serbuk simplisia diekstrak dengan cara refluks menggunakan pelarut etanol 80%. Dengan uji aktivitas penghambatan enzim xantin oksidase didapatkan ekstrak yang aktif yaitu ekstrak akar sidaguri (Sida rhombifolia), ekstrak kulit batang nyamplung (Callophylum inophyllum), dan ekstrak daun gandarusa (Justicia gendarussa) yang mempunyai nilai IC50 berturut-turut 1622 ppm, 2832 ppm, dan 5824, 49 ppm. Dari hasil uji kinetika enzim diketahui bahwa ekstrak akar sidaguri mempunyai aktivitas penghambatan kompetitif. Identifikasi kimia pada ekstrak sidaguri menunjukkan adanya alkaloid, flavonoid, tanin, dan saponin. Pada ekstrak kulit batang nyamplung mengandung flavonoid, tanin, dan saponin, sedangkan pada ekstrak daun gandarusa menunjukkan adanya alkaloid, flavonoid, tanin, saponin, dan antrakuinon.

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Overproduction and excessive excretion of uric acid in the body can cause hyperuricemia. Xanthine oxidase is an enzyme that plays a role in catalyzing the oxidation hypoxanthine and xanthine into uric acid. The purpose of this study is to find medicinal plants which have inhibited the enzyme xanthine oxidase activity and identification the chemical contain. The method used to test the inhibitory activity of the enzyme xanthine oxidase is a Continous Spectrophotometric Rate Determination. The simplisia powder was extracted by reflux using 80% ethanol solvent. By testing the enzyme xanthine oxidase inhibitory activity obtained an active extract, that is sidaguri (Sida rhombifolia) root extract, nyamplung (Calophyllum inophyllum) bark extract, and gandarusa (Justicia gendarussa) leaf extract with IC50 values 1622 ppm, 2832 ppm, and 5824,49 ppm. The kinetics results are known to sidaguri root extract have a competitive inhibitory activity. Chemical identification in sidaguri root extract is showed alkaloids, flavonoids, tannins, and saponins. Nyamplung bark extract is contain flavonoids, tannins, and saponins, while gandarusa leaf extract showed alkaloids, flavonoids, tannins, saponins, and anthraquinone."