OPTIMIZATION AND VALIDATION OF AN ULTRASOUND-BASED TECHNIQUE FOR THE ANALYTICAL EXTRACTION OF TRYPTOPHAN IN RED ALGAE (Kappaphycus spp.)
Nuzulia Izmi, Dr. Widiastuti Setyaningsih, S.T.P.,M.Sc ; Prof. Miguel Palma Lovillo
2024 | Tesis | S2 Ilmu dan Teknologi Pangan
Kappaphycus spp. merupakan rumput laut yang paling banyak dibudidayakan di Indonesia. Spesies ini terkenal dengan berbagai senyawa bioaktifnya, salah satunya adalah triptofan. Optimalisasi dan validasi metode analitik ekstraksi berbantuan ultrasonik (UAE) telah berhasil menentukan kadar triptofan pada Kappaphycus spp. Empat faktor dan tiga level digunakan dalam desain Box-Behnken (BBD) bersama dengan metodologi permukaan respons (RSM): komposisi pelarut (x1; 50, 70, 90% metanol dalam air), pH (x2; 2, 5, 8), amplitudo (x3; 25, 50, and 75%) dan siklus kerja pulsa (x4; 0.2, 0.6, 1.0 s-1). Kondisi ekstraksi optimum diperoleh dengan mengaplikasikan pelarut ekstraksi metanol 73?lam air dengan pH 8, lama ekstraksi 10 menit pada suhu 60°C, amplitudo 58%, pulse duty-cycle 0,8 s-1 , dan rasio pelarut terhadap sampel 25:1. Pemulihan yang tinggi dicapai dengan spiking (>90% pemulihan) dan presisi berhasil diperoleh melalui kemampuan pengulangan (CV, 2,29%) dan presisi menengah (CV, 4,52%) yang divalidasi dengan nilai yang dapat diterima (CV <5>Kappaphycus striatumdan Kappaphycus alvarezii di lokasi dan metode budidaya yang berbeda. Studi ini memiliki informasi tentang kandungan triptofan pada Kappaphycus spp. yang dapat bermanfaat bagi petani rumput laut untuk meningkatkan produktivitas.
Kappaphycus spp. was the most cultivated seaweed in Indonesia. It is well known for its multiple bioactive compounds, some related to tryptophan. Optimized and validated an analytical ultrasound-assisted extraction (UAE) method has successfully determined the tryptophan levels in Kappaphycus spp. Four factors and three levels were used in a Box-Behnken design (BBD) together with the response surface methodology (RSM): solvent composition (x1; 50, 70, 90% methanol in water), pH (x2; 2, 5, 8), amplitude (x3; 25, 50, and 75%). and pulse duty-cycle (x4; 0.2, 0.6, 1.0 s-1). An optimum extraction condition was obtained by applying an extraction solvent 73% methanol in water with pH 8, an extraction period of 10 minutes at a temperature of 60 °C, an amplitude of 58%, a pulse duty- cycle of 0.8 s-1, and a solvent-to-sample ratio of 25:1. A high recovery was achieved by spiking (>90% of recovery) and the precision was successfully obtained through repeatability (CV, 2,29%) and intermediate precision (CV, 4,52%) that were validated by the acceptable values (CV<5>Kappaphycus striatum and Kappaphycus alvarezii in different cultivation sites and methods. Indeed, having information about the tryptophan content in Kappaphycus spp. can be valuable for seaweed farmers to increase productivity.
Kata Kunci : Kappaphycus striatum, Kappaphycus alvarezii, Optimization, Box Behnken design, UPLC-FD
