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Abstrak :
Propolis merupakan suatu kekayaan alam yang dihasilkan dari lebah selain madu. Salah satu kandungan propolis yang memiliki manfaat besar dari bioaktivitasnya adalah Artepillin C. Artepillin C merupakan suatu derivat asam sinamat terprenilasi pada posisi meta dari gugus karboksil dalam cincin aromatis. Sintesis asam sinamat dengan dilanjutkan dengan reaksi prenilasi adalah suatu cara untuk melakukan pendekatan menuju sintesis Artepillin C. Asam sinamat yang digunakan adalah hasil sintesis dari benzaldehida dan anhidrida asetat dengan bantuan katalis kalium asetat. Karakterisasi dengan UV-Vis menunjukkan λmax sebesar 279 nm. Hasil FT-IR spesifik asam sinamat pada 3070nm sebagai penunjuk OH karboksilat dan 1681 nm sebagai gugus karbonil. Asam sinamat hasil sintesis diprenilasi dengan dua katalis heterogen, yaitu γ-Al2O3/NaOH/Na dan K2CO3. Keduanya memiliki hasil yang serupa baik dari hasil karakterisasi spektrofotometer FT-IR dengan kemunculan peak pada daerah 1400 nm, spektrofotometer UV-Vis dengan adanya pergeseran batokromik, maupun LC-MS dengan keberadaan peak yang mirip. Pada asam sinamat yang telah mengalami prenilasi ini dilakukan uji aktivitas antioksidan dan dikarakterisasi menggunakan spektrofotometer UV-Vis dengan panjang gelombang 517 nm. Adanya persentase kenaikan aktivitas antioksidan sebesar 27,28% membuktikan bahwa asam sinamat terprenilasi memiliki aktivitas lebih baik dibandingkan asam sinamat hasil sintesis.

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Propolis is a natural resource produced by bees other than honey. One component in propolisthat has the benefit for its bioactivity is Artepillin C. Artepillin C is a prenylated cinnamic acid derivatives at the meta position of the carboxyl group in the aromatic ring. Synthesis of cinnamic acid followed by the reaction with dimethyl allyl bromide is a way to synthesize Artepillin C. Cinnamic acid was synthesized from benzaldehyde and acetic anhydride in the presence of potassium acetate as the catalyst. The characterization by spectrophotometer UV-Vis showed the λmax at 279 nm. The spectrophotometer FT-IR results of cinnamic acid showed the specific absorbancypeak at 3070 nm of OH carboxylate and at 1681 nm of carbonyl groups. Prenylation of cinnamic acid was conducted using two heterogeneous catalysts, namely γ-Al2O3/NaOH/Na and K2CO3. Both catalysts showed similar results based onspectrophotometer FT-IR with peak emergence in the 1400 nm region, spectrophotometer UV-Vis with a bathochromic shift, so doLC-MS in the presence of a similar peak. Antioxidant activity test is done onprenylated cinnamic acid using spectrophotometer UV-Vis at 517 nm. The increased antioxidant activity of27.28% proved that the prenylated cinnamic acid had better antioxidant activity than the original cinnamic acid.

Abstrak :
In order to enhance adsorption capacity of gibbsite (Al(OH)3 as an adsorbent for the adsorption of phosphate in water, gibbsite was modified through lithium-intercalation. The purification method of Tributh and Lagaly was applied prior to intercalation. The Li-Intercalation was prepared by the dispersion of gibbsite into LiCl solution for 24 hours. This intercalation formed an cationic clay with the structure of [LiAl2(OH)6]+ and exchangeable Cl- anions in the gibbsite interlayer. A phosphate adsorption test using Lithium-intercalated gibbsite (LIG) resulted in optimum adsorption occurring at pH 4.5 with an adsorption capacity of 11.198 mg phosphate/g LIG which is equivalent with 1.04 wt% LIG. The adsorption capacity decreased with decreasing amounts of H2PO4-/HPO4- species in the solution. This study showed that LIG has potential as an adsorbent for phosphate in an aqueous solution with pH 4.5?9.5.

Abstrak :
The purification of recombinant proteins is an important stage in biopharmaceutical research. A commonly used technique is immobilized metal affinity chromatography (IMAC). One of the main advantages of this type of chromatography is that the column can easily be regenerated for subsequent purification work. The mechanism of IMAC is based on bonding between metal ions immobilized on a matrix with a specific amino acid. Because of the strong interactions of the electron donor group on the imidazole ring, histidine is often used in the IMAC purification system. Two types of commercial IMAC resin use a nitrilotriacetic acid (NTA) matrix: a nickel-based (Ni-NTA) and cobalt-based (Co-NTA), better known as TALON. This study was aim to investigate the effect of the metal ions Ni2+ and Co2+ to purify recombinant human erythropoietin (rhEPO) expressed in yeast system Pichia pastoris. The results indicated that both Ni-NTA and Co-TALON gave almost the same level of protein purity; however, Ni-NTA has a higher binding affinity than Co-TALON might be due to the higher stability complex of Ni+. The average amount of protein bound by Ni-NTA and Co-TALON was 183.5 and 38.7 μg/mL, respectively.