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Abstrak :
Penelitian ini bertujuan untuk melakukan sintesis turunan asam amino dari asam laurat membentuk senyawa lipoamida. Penelitian ini diawali dengan esterifikasi asam laurat menggunakan dry metanol dan bantuan katalis asam HCl pekat. Selanjutnya, campuran tersebut diekstrasi dengan air untuk mendapatkan fasa organiknya berupa metil laurat dan dimurnikan menggunakan kromatografi kolom. Kemudian metil laurat diamidasi dengan asam amino glisin dan fenilalanin agar dihasilkan senyawa lipoamida glisin-laurat dan fenialanin-laurat. Produk yang terbentuk dikarakterisasi menggunakan FTIR. Hasilnya menunjukkan bahwa masing-masing produk ester memberikan pita serapan medium vibrasi C-N pada bilangan gelombang 1026,17 cm-1 pada glisin-laurat dan 1015,56 cm-1 pada fenilalanin-laurat. Hasil uji toksisitas melalui metode BSLT terhadap larva Artemia salina L. didapatkan nilai LC50 senyawa lipoamida glisin-laurat dan fenilalanin-laurat, masing-masing sebesar 175,724 ppm, dan 1494,729 ppm. Uji aktivitas antimikroba dari semua produk lipoamida menunjukkan adanya aktivitas antimikroba. Kedua senyawa lipoamida memiliki zona hambat yang sama terhadap pertumbuhan bakteri Escherichia coli, sebesar 10 mm, sedangkan senyawa glisin-laurat dan fenilalanin-laurat memiliki zona hambat terhadap pertumbuhan bakteri Staphylococcus aureus, secara berurutan 7 mm dan 8 mm. ......This study discusses about synthesis of amino acid with lauric acid to form lipoamida compound which has toxicity property. In this research, esterification of lauric acid with dry methanol using concentrated HCl as acid catalyst. Furthermore, the solution was extracted with water to obtain organic phase (methyl laurate) and purified by column chromatography. Then, amidation of methyl laurate with the amino acids, glycine and phenylalanine, respectively. Amidation reaction produces glycine-laurate and phenylalanine-laurate lipoamida compounds. All of ester products were identified using FTIR. The results showed that each lipoamida product gave absorption band C-N at the range of wave number 1026,17 cm-1 for glycine-laurate dan 1015,56 cm-1 for phenylalanine-laurate. The results of the toxicity test using the BSLT method on Artemia salina L. larvae obtained the LC50 values of glycine-laurate and phenylalanine-laurate lipoamida compounds, respectively 175,724 ppm and 1494,729 ppm. Antimicrobial activity test of all lipoamida products had antimicrobial activity. Both lipoamida compounds have the same zone of inhibition for the growth of Escherichia coli bacteria, which is 10 mm. Meanwhile, glycine-laurate and phenylalanine-laurate compounds had zone a inhibition against the growth of Staphylococcus aureus bacteria, respectively 7 mm and 8 mm.

Abstrak :
Pada penelitian ini, asam risinoleat diesterifikasi dengan dry metanol dan katalis KOH dengan sistem reflux. Metil risinoleat yang terbentuk dioksidasi pada ikatan rangkapnya membentuk diol menggunakan KMnO4 encer dalam suasana basa pada suhu 0oC. Metil risinoleat kemudian diamidasi menggunakan asam amino glisin dan asam amino fenilalanin untuk menghasilkan senyawa lipoamida. Hasil karakterisasi lipoamida yang terbentuk menggunakan FTIR menunjukkan adanya pita serapan ulur N-H dan O-H yang overlaping pada bilangan gelombang 3445,47 cm-1 untuk lipoamida glisin-risinoleat dan 3434,06 cm-1 untuk lipoamida fenilalanin-risinoleat. Selain itu, muncul puncak serapan medium vibrasi C-N pada bilangan gelombang 1217,90 cm-1 pada lipoamida glisin-risinoleat dan 1217,59 cm-1 pada lipoamida fenilalanin-risinoleat. Hal ini menunjukkan ikatan amida yang terbentuk dari proses amidasi. Hasil uji sitotoksik MTT senyawa lipoamida terhadap sel HeLa menunjukkan bahwa nilai IC50 lipoamida glisin-risinoleat sebesar 120 µg/mL yang termasuk ke dalam kategori cukup aktif, sedangkan IC50 lipoamida fenilalanin-risinoleat sebesar 250 µg/mL yang tergolong memiliki sifat sitotoksisitas yang lemah terhadap sel HeLa. ......In this study, ricinoleic acid from castor oil was esterified with dry methanol and KOH catalyst using the reflux system. The methyl ricinoleate formed was oxidized on its double bonds to form a diol using dilute KMnO4 under alkaline conditions at 0oC. Methyl ricinoleate was then reacted through amidation process using amino acid glycine and amino acid phenylalanine to produce lipoamides. The results of characterization of lipoamides formed using FTIR showed that there were overlapping N-H and O-H stretch bands at wave numbers 3445.47 cm-1 for glycine-ricinoleate lipoamide and 3434.06 cm-1 for phenylalanine-ricinoleate lipoamide. In addition, the medium absorption peak of C-N appeared at the wave number 1217.90 cm-1 for glycine-ricinoleate lipoamide and 1217.59 cm-1 for phenylalanine-ricinoleate lipoamide. These showed that the amide bonds were formed from the amidation process. The results of the MTT cytotoxic assay of lipoamide compounds against HeLa cells showed that the IC50 value of glycine-ricinoleate lipoamide was 120 µg / mL which was considered quite active, while the IC50 value of phenylalanine-ricinoleate lipoamide was 250 µg / mL which was classified as having weak cytotoxicity properties against HeLa cells