Kitosan dari cangkang udang dan aplikasi kitosan sebagai antibakteri pada kain katun

PURNAWAN, Candra, Dr.rer.nat. Nurul Hidayah Aprilita, M.Si

2008 | Tesis | S2 Ilmu Kimia

Telah dilakukan kajian tentang isolasi kitosan dari cangkang udang dan aplikasinya sebagai bahan antibakteri pada kain katun. Dalam penelitian ini telah diteliti pengaruh konsentrasi NaOH, temperatur, waktu, dan re-deasetilasi terhadap derajat deasetilasi (DD) dan berat molekul (BM) kitosan; hubungan DD dengan derajat kristalinitas kitosan; pengaruh konsentrasi kitosan terhadap sifat lapisan kitosan pada kain katun; pengaruh konsentrasi dan DD kitosan terhadap aktivitas antibakteri kain katun yang telah dilapisi kitosan. Aktivitas antibakteri ditentukan terhadap bakteri Staphylococcus aureus. Hasil penelitian menunjukkan bahwa semakin besar konsentrasi NaOH, temperatur, waktu dan re-deasetilasi maka DD kitosan yang dihasilkan semakin besar namun tidak mempengaruhi secara signifikan terhadap BM kitosan. Kondisi optimum proses deasetilasi pada penelitian ini adalah 60% NaOH, 120 °C, re-deasetilasi 3 kali dengan total waktu 3 jam. Jika DD kitosan antara 50-65% maka kristalinitas kitosan mengalami perubahan signiflkan lebih rendah dari kristalinitas kitin. Kemudian jika DD kitosan lebih besar dari 65% maka kristalinitas kitosan meningkat dengan meningkatnya DD kitosan. Interaksi antara kitosan dengan selulosa kain diperkirakan melalui interaksi secara kimia antara -OH selulosa dan -OH kitosan. Aktivitas kain antibakteri optimum pada konsentrasi kitosan 0,1% (b/v) dan semakin tinggi DD kitosan, aktivitas daya hambat kain antibakteri semakin besar. Aktivitas daya hambat kain antibakteri sebelum pencucian (laundering) lebih besar daripada sesudah pencucian dalam waktu kontak di bawah 12 jam. Pada waktu kontak di atas 12 jam, aktivitas daya hambat kain antibakteri sebelum pencucian (laundering) lebih kecil daripada sesudah pencucian.

Isolation chitosan from shrimp's shell and application of chitosan as an antibacterial agent on cotton fabrics have been investigated. This research investigated the effect of NaOH concentration, temperature, time and deacetylation on the degree of deacetylation (DD) and chitosan molecular weight (MW), a relationship between the degree of deacetylation (DD) and degree of chitosan crystallinity; the effect of chitosan concentration on the characteristic of chitosan layer on cotton fabrics; the effect of chitosan concentration and degree of deacetylation on the antibacterial activity of cotton fabrics. The · antibacterial activity was determined against Staphylococcus aureus. The results showed that the greater NaOH concentration, temperature, time, and re-deacetylation, the greater the degree of deacetylation of the chitosan. However, it did not significantly affect the molecular weight of chitosan. Deacetylation process optimal condition of this research was 60% NaOH, 120 OC, re-deacetylated 3 times with total time of 3 hours. If chitosan degree of deacetylation between 50-65%, the chitosan crystallinity experiences a significant changing which is lower than the chitin crystallinity. Moreover, if chitosan degree of deacetylation is more than 65% as chitosan degree of deacetylation increases, the chitosan crystallinity also increases. The interaction between chitosan and fabrics cellulose is predicted through chemical interactions between -OH cellulose and -OH chitosan. The optimum activity of antibacterial fabrics was achieved at 0.1 % (w/v) chitosan. The greater the chitosan degree of deacetylation, the greater the antibacterial activity of the antibacterial fabrics. At bacterial growth less than 12 hours, the antibacterial activity of the coated fabrics before laundering was higher than those after laundering. But, after 12 hours bacterial growth, the adverse effect took place.

Kata Kunci : Kitosan,Kain katun,Antibakteri