Hasil Pencarian  ::  Simpan CSV :: Kembali

"Tanaman dari genus ferula merupakan bahan alam yang mengandung senyawa gercumin. Gercumin merupakan derivat kurkumin yang mengalami prenilasi pada gugus –OH dari cincin aromatis kurkumin. Mengisolasi kurkumin dilanjutkan dengan reaksi prenilasi salah satu cara untuk mensintesis senyawa gercumin. Kurkumin yang digunakan dalam prenilasi adalah kurkumin hasil isolasi dengan metode maserasi dengan pelarut etanol dan pemisahannya digunakan kromatografi kolom. Hasil analisis LC-MS kurkumin menunjukan nilai m/e=369 (M+H). Kurkumin hasil isolasi diprenilasi dengan dua katalis heterogen, yaitu SiO2-H2SO4 dan K2CO3. Kedua produk prenil memiliki hasil yang serupa dari karakterisasi spektrofotometer FT-IR dengan munculnya peak pada daerah 1400 cm-1. Hasil analisis dengan LC-MS menunjukan nilai m/e = 505. Dimana, pada nilai tersebut diduga 2 gugus prenil yang masuk ke dalam kurkumin. Kurkumin terprenilasi dilakukan uji aktivitas antioksidan dan dikarakterisasi dengan spektrofotometer UV-Vis dengan panjang gelombang 517 nm lalu dibandingkan. Adanya persentase kenaikan aktivitas antioksidan sebesar 39,4% membuktikan bahwa kurkumin terprenilasi memiliki aktivitas antioksidan lebih baik dibandingkan dengan kurkumin hasil isolasi.

---

Plant from genus ferula is natural product containing gercumin compounds. Gercumin is a prenylated curcumin at the –OH position from the aromatic ring of curcumin. Isolate of curcumin followed by the reaction with dimethyl allyl bromide is a way to synthesize compounds gercumin. Curcumin used in prenylation is isolated by maceration with ethanol solvent and separated by column chromatography . Result from analysis LC-MS showed curcumin value m/e = 369 (M+H). Prenylation of curcumin was conducted using two heterogeneous catalysts, namely SiO2-H2SO4 and K2CO3. Both products prenylation have similar results of FT-IR spectrophotometer characterization with the advent of the peak at 1400 cm-1 region, results with LC-MS analysis showed the value of m / e = 505. So, on the value m/e has possibility that there are two prenyl groups get into curcumin. Prenylated curcumin was tested antioxidant activity and characterized by UV-Vis spectrophotometer with a wavelength of 517 nm and compared. The existence of the percentage increase in the antioxidant activity of 39,4% prenylated curcumin proved that it has better antioxidant activity than isolated curcumin without prenylation."

"Sinamaldehida merupakan salah satu produk bahan alam yang paling melimpah yang ditemukan pada kulit kayu spesies Cinnamomum dan terkenal karena aplikasinya dalam medis, pemberi cita rasa, industri parfum, dan sebuah intermediet berharga untuk banyak produk organik sintesis. Pada penelitian ini, sinamaldehida disintesis dengan reaksi katalitik homogen dan heterogen. Reaksi katalitik homogen dilakukan menggunakan larutan NaOH, sedangkan reaksi katalitik heterogen dilakukan menggunakan beberapa katalis padatan basa, yang mana katalis NaOH/Al2O3 yang dipreparasi dengan mencampur dan menggerus padatan NaOH dan Al2O3 (14 % berat Al2O3) telah sukses menampilkan reaksi kondensasi aldol silang dalam menghasilkan sinamaldehida. Katalis yang telah disiapkan dikonfirmasi dengan metode XRD. Reaksi kondensasi aldol antara benzaldehida dan asetaldehida dilakukan pada 70 oC dengan memvariasikan waktu reaksi. Produk reaksi dianalisis dengan GC dan GC-MS. Konsentrasi katalis = 3,5 % (% berat total reagen); rasio molar antara benzaldehida dan asetaldehida = 1,1:1; dan waktu reaksi 6 jam; distribusi produk sinamaldehida yang didapat 8,06 %.

---

Cinnamaldehyde is one of the most abundant natural product found in Cinnamomum sp. bark and is well known for its application in medicine, flavor, perfumery, and also a valuable intermediate compound for many synthesized organic products. In this research, cinnamaldehyde was synthesized by homogeneous and heterogeneous catalytic reactions. The homogeneous catalytic reaction was conducted using solution of NaOH, where as the heterogeneous catalytic reaction were conducted using some solid base catalysts, in which the catalyst NaOH/Al2O3 prepared by mixing and grinding solids of NaOH and Al2O3 (14 % of Al2O3 weight) has succeeded to perform the cross aldol condensation reaction of benzaldehyde and acetaldehyde in producing cinnamaldehyde. The catalyst prepared was confirmed by XRD method. The aldol condensation reaction of benzaldehyde and acetaldehyde were conducted at 70 oC by varying the reaction times. Reaction product was analyzed by GC and GC-MS. The catalyst concentration was 3,5 % (% weight of total reagents); molar ratio between benzaldehyde and acetaldehyde was 1,1:1; and time reaction was 6 hours; the distribution product cinnamaldehyde obtained was 8,06 %."