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Abstrak :
Propolis adalah campuran dari beberapa resin yang memiliki berbagai macam khasiat antara lain sebagai antitumor dan antikanker. Penelitian ini dilakukan untuk menganalisa adanya Artepillin C dan fenetil kafeat (CAPE) yaitu suatu senyawa dalam propolis yang bertanggung jawab terhadap khasiat tersebut. Alat yang digunakan adalah kromatografi cair kinerja tinggi (KCKT) dengan fase gerak asam format 1,5% dalam air - asam format 1,5% dalam asetonitril dengan komposisi fase gerak 6:4. Laju alir yang digunakan 1,8 mL/menit dimulai menit ke-0 hingga menit ke-8, selanjutnya pada menit ke-8 hingga menit ke-10 diubah menjadi 1,0 mL/menit, dan pada menit ke-10 diubah kembali menjadi 1,8 mL/menit. Setiap sampel dilarutkan dengan metanol sehingga didapat konsentrasi tertentu, lalu disuntikan ke KCKT dengan volume penyuntikan 20 μl. Deteksi dilakukan dengan menggunakan detektor UV dan PDA pada panjang gelombang optimum 315 nm. Hasil pengujian menunjukkan hanya pada sampel A dan D yang terdeteksi adanya CAPE dengan kadar 0,382 μg/mL pada sampel A dan 0,291 μg/mL pada sampel D sedangkan Artepillin C tidak terdeteksi pada semua sampel.

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Propolis is a resinous mixture wich has a variety of benefits, as antitumor and anticancer. This research is done to analyze the existence of Artepillin C and caffeic acid phenethyl ester (CAPE), both of them are compound in propolis which responsible to their benefit. The instrument which used in this research was high performance liquid chromatography (HPLC) with mobile phase used 1.5% formic acid in water-1.5% formic acid in acetonitrile with composition of 6:4. Flow rate used 1.8 mL/min starting from zero minute to eighth minute, and then in the eighth minute to tenth minute was changed to 1.0 mL/min, and at tenth minute is changed back to 1.8 mL/min. Each sample dissolved with methanol until got a certain concentration, and then injected into HPLC with 20 μl injection volume. Detection was done by using UV detector and PDA detector at the optimum wavelength of 315 nm. The results showed only the sample A and D which detected the existence of CAPE, detectable levels of 0.382 μg/mL in sample A and 0.291 μg/mL in sample D, while Artepillin C undetectable in all samples.

Abstrak :
Caffeic acid dapat dianggap sebagai natural anti-oxidant yang esensial Namun, rendahnya solubilitas dan stabilitas caffeic acid di berbagai macam pelarut membatasi applikasi pada industri. Sintesis dari alkyl ester caffeic acid sangat menguntungkan berdasarkan fungsi biologis maupun potensi aplikasinya. Salah satu turunan dari caffeic acid, caffeic acid phenethyl ester CAPE merupakan senyawa dengan banyak aktivitas biologis yang berguna. Metode untuk mensintesis CAPE adalah dengan esterifikasi menggunakan katalis ion exchange resin. Tahap pertama merupakan esterifikasi dari caffeic acid dengan metanol untuk memproduksi metil kafeat. Kondisi reaksi dan parameter kinetika untuk reaksi sintesis metil kafeat dengan methanol menggunakan cation-exchange resin sebagai katalis akan dianalisis dan produk metil kafeat dikonfirmasi menggunakan Ultra Peroformance Liquid Chromatography UPLC . Kondisi optimum dimana produk metil kafeat tertinggi dihasilkan adalah sebagi berikut: suhu reaksi 60 C dan waktu reaksi 4 jam. Kinetika reaksi diasumsikan menggunakan pseudo-homogenous first order model dan hubungan antara suhu dan forward rate constant menghasilkan energi aktivasi 51 kJ/mol. Hasil tersebut mengindikasikan bahwa cation-exchange resin memiliki aktivitas katalisis yang tinggi.

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Caffeic acid CA could be considered as an important natural anti oxidant. However, the low solubility and stability of CA in various solvent is limiting the application in industry. It is advantageous to synthesize alkyl ester of caffeic acid based on both their biological function and potential application. One of the caffeic acid derivatives called caffeic acid phenethyl ester CAPE is a compound with numerous important biological activities. To synthesize CAPE one of the method used is catalyzed esterification of caffeic acid and phenethyl alcohol using ion exchange resin catalyst. The first step of the process is to perform esterification of caffeic acid and methanol to produce methyl caffeate MC . MC would then be used to produce CAPE in the presence of phenethyl alcohol. Herein, the reaction condition and kinetic parameters for the synthesis of MC using cation exchange resin as a catalyst were investigated, and the product was confirmed by ultra performance liquid chromatography UPLC . The highest yield of MC catalyzed by cation exchange resin attained under the optimum condition as follows reaction temperature of 60 C and a reaction time of 4 h. The esterification kinetics of CA and methanol is described by the pseudo homogenous first order model. The relationship between temperature and the forward rate constant gives activation energy of 51 kJ mol. These results indicated that cation exchange resin possesses high catalytic activity in the synthesis of MC, which is an efficient catalyst suitable for MC production.

Abstrak :
Implan tulang belakang obat antituberkulosis (OAT) berpotensi mengatasi ketidakpatuhan pasien spondilitis tuberkulosis dan meningkatkan daya jangkau obat ke daerah luka. Namun, peningkatan stres oksidatif karena respon tubuh terhadap infeksi patogen berpotensi mengakselerasi degradasi OAT isoniazid (INH) dan pirazinamid (PZA). Uji degradasi paksa dilakukan dengan terlebih dahulu membuat kurva kalibrasi obat dan menstandardisasi H2O2 stok. Sampel INH dan PZA disimpan selama 5 hari dalam media phosphate buffered saline (pH 7,4) dengan kadar H2O2 3% (w/v). Konsentrasi zat diukur dengan instrumen high performance liquid chromatography (HPLC) Shimadzu LC 20AD dengan kolom C18 (250 x 4,6 mm x 5 µm). Sampel INH dan PZA tersebut mengalami degradasi sebesar 54,01% dan 8,67% secara berurutan. Untuk menghambat degradasi, kedua obat ditambahkan stabilisator asam galat (AG), asam kafeat (AK), atau asam askorbat (AA) dengan perbandingan massa 1:1. Hasil uji degradasi menunjukkan bahwa penambahan AG paling signifikan menghambat degradasi INH dan PZA hingga ke angka 4,96% dan 2,27% secara berurutan. ......Orally administered first line antituberculosis drugs (ATD) have risk of low patient adherence and low bioavailability in bone tissue. Unfortunately, elevated oxidative stress around infection area could endanger two ATDs, isoniazid (INH) and pyrazinamide (PZA), stability and further limit its release. Forced degradation study was conducted by prior creation of calibration curves and standardization of H2O2 stock concentration. INH and PZA samples were kept for 5 days in phosphate buffered saline (pH 7.4) aqueous media, H2O2 concentration was adjusted to 3% (w/v). Concentration of analyte was measured with Shimadzu LC 20AD, paired with C18 (250 x 4.6 mm x 5 µm) column, high performance liquid chromatography (HPLC). INH and PZA showed 54.01% and 8.67% degradation, respectively. To inhibit degradation; gallic acid (AG), caffeic acid (AK), and ascorbic acid (AA) stabilisator were added with 1:1 mass ratio to ATD. In both ATDs sample, AG showed the most significant results. Degradation was lowered to 4.96% and 2.27% for INH and PZA, respectively.