Judul: Mikroenkapsulasi Ekstrak Rimpang Temulawak (Curcuma xanthorriza. Roxb) Tersalut Gel Kitosan-Alginat
Abstrak: Microencapsulation was done using the temulawak extract with curcumin as a target material. The aims of this research were to study (1) the transport properties of curcumin passing through the chitosan-alginate membranes due to diffusion process, (2) the optimum condition of in vitro dissolution behavior, and (3) the effects of oxidation and hydrolysis to storage conditions of curcumin coated chitosan-alginate gel. The maceration process using ethanol yields 17.08% and the content of the curcumin in the extract detected by visible spectrophotometry λ 430 nm was 10.30%. Chitosan-alginate membranes were prepared by mixing 100 ml chitosan 2.50% (b/v); 16.7 ml alginate 0.62% (b/v); and 1.70 ml glutaraldehide 4.63% (v/v) solutions, were poured into mould. Membranes thickness was varied by changing chitosan solution volume. Then, the membranes were used in diffusion assay at 37 and 40oC. Two degrees of donor concentration (Cd) was used 4 and 8 g/l, whereas recipient compartment was filled with solvent. Aliquots were taken after 30, 60, 90, 120, 150, and 180 minutes. The Aliquots absorbance was measured at λ 430 nm. Based on linear regression method, it was found that the influence of T, Cd, and h on D, J (Fick), and D, Jo (Higuchi), were not significant. On the other hand, the influence of T, Cd, and h on D, J (Fick), and D, Jo (Higuchi) using response surface method yield model equations with R2 98.6% and 99.4%. Matrix formation of curcumin for sustained released which is coated by chitosan-alginate gel ware made in a form of a microencapsulation using spray dryer technique. Its optimum condition was obtained using response surface method at concentrations ratio of alginate 0.62% (b/v) and glutaraldehide 4.63% (v/v) respectively, while chitosan concentration was fixed (1.75% [b/v]). The dissolution assay was done at 37oC, at 100 rpm of stirring rate in 8 hours. Aliquots were taken at 15, 30, 45, 60, 90, 120, 150, 180, 240, 300, 360, 420, 480 minutes. Absorbance of the Aliquots was measured at λ 430 nm. The curcumin released has the best linear correlation to the first order reaction with released constant, k = 2.25.10-3 minute-1 while it’s half live is t1/2= 5.16 hours. Release curcumin was determined mainly by diffusion mechanism. The Higuchi model was better than Fick model for determined the dissolution process. The storage assay for the microencapsulation process of temulawak ethanol extract showed that the room temperature was the best condition for maintaining the curcumin release. In this case, the data was suitable with the third order reaction with released constant, k = 0.6193 10-3 week-1 while it’s half life was t1/2 = 29.90 week.
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Judul: Pembuatan dan Karakterisasi Nanopartikel Ekstrak Temulawak dengan Metode Ultrasonikasi, Production and Characterization of Curcuma xanthorrhiza Roxb. Extract Nanoparticles using Ultrasonication Method
Abstrak: Ekstrak temulawak diketahui memiliki khasiat obat sebagai antioksidan, antiinflamasi, antibakteri, dan antijamur. Namun, konsumsi ekstrak temulawak secara oral menimbulkan rasa getir dan memiliki bioavailabilitas rendah. Salah satu upaya yang dapat dikembangkan untuk mengatasi permasalahan tersebut adalah penyalutan dengan menggunakan nanokitosan. Ultrasonikasi merupakan salah satu metode yang dapat digunakan untuk pembuatan nanopartikel ekstrak temulawak. Penelitian ini bertujuan memperoleh nanopartikel ekstrak temulawak dengan metode ultrasonikasi serta karakterisasi fisik hasil baik morfologi, gugus fungsi maupun derajat kristalinitas. Penelitian ini menggunakan perlakuan waktu sonikasi (30 dan 60 menit), penggunaan TPP, dan proses penambahan ekstrak temulawak. Data yang diperoleh menghasilkan perlakuan terpilih yaitu dengan penggunaan TPP dan dua kali ultrasonikasi selama 60 menit yang dikeringkan dengan pengering semprot. Rendemen nanopartikel ekstrak temulawak yang dihasilkan dari perlakuan terpilih sebanyak 5,47%. Ukuran nanopartikel yang diperoleh dari perlakuan terpilih dengan menggunakan SEM berkisar 470 – 3000 nm. Permukaan nanopartikel ekstrak temulawak lebih halus dan cembung dibandingkan dengan nanokitosan. Karakterisasi FTIR menunjukkan tidak adanya gugus fungsi kurkumin yang khas pada sampel nanopartikel ekstrak temulawak dengan dua kali ultrasonikasi selama 30 menit dan 60 menit. Akan tetapi, terjadi kenaikan derajat kristalinitas pada sampel nanopartikel ekstrak temulawak dibandingkan dengan nanokitosan. Hasil ini menunjukkan adanya senyawa pengisi dalam kitosan., Curcuma xanthorrhiza Roxb. extract is known to have antioxidant, antiinflammatory, antibacterial, and antifungal activities. However, it cause a taste of bitterness and also has a low bioavailability. One of the efforts that can be developed to solve this problem is encapsulation using nanochitosan. Ultrasonication is one of the methods that can be used to produce Curcuma xanthorrhiza Roxb. extract nanoparticles. This research has focused on gaining Curcuma xanthorrhiza Roxb. extract nanoparticles using ultrasonication, physical characterization of morphology, functional groups, and crystanility degree. This research has used the treatment of sonication time (30 and 60 minutes), usage of TPP, and the additon process of Curcuma xanthorrhiza Roxb. extract. The data has shown that the choosen treatment to produce Curcuma xanthorrhiza Roxb. extract nanoparticles by the addition of TPP and twice 60 minutes ultrasonication which drying by spray dryer. The yield of nanoparticles that resulting from the choosen treatment is 5,47%. Nanoparticles size of the choosen treatment ranges from 470 – 3000 nm by SEM. Curcuma xanthorrhiza Roxb. extract nanoparticles surface more smooth and convex than nanochitosan. The characterization of FTIR has shown no presence of curcumin functional groups at Curcuma xanthorrhiza Roxb. extract nanopartikel by twice ultrasonication for 30 and 60 minutes. However, there is crystalinity degree increase of Curcuma xanthorrhiza Roxb. extract nanoparticles compared than nanochitosan. This result has shown the presence of filler compounds in chitosan.
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Judul: Pengembangan model probabilistic neural network (PNN) pada pengenalan kisaran usia dan jenis kelamin berbasis suara
Abstrak: Voice signal can be used to represent a speaker. Voice can also be used to recognize the age range and the gender of the speaker, because of the difference in frequency of the voice signal for different age and gender. Age range for this experiment is divided into children (8-10 years old), teenagers (12-17 years old) and adults (30-50 years old). We performed feature extraction to obtain a representation of the speaker using Mel-Frequency Cepstrum Coefficient (MFCC). MFCC is used with 13, 20, 26 coefficients. Probabilistic Neural Network (PNN) is used as the feature matching model. The PNN model is constructed from three different proportions of TRD (Training data) : TSD (Testing data) (25%:75%, 50%:50%, 75%:25%). MFCC with 26 coefficient gives the best accuracy of 93.47%. The proportion of 75% (TRD) : 25% (TSD) also gives the best accuracy of 94.22%. PNN-age and PNN-gender identification result in an accuracy of 91.26%. Specifically, PNN accuracy percentage for male and female are 92.26%, and 95.20%, respectively, while for children, teenagers and adults the accuracies are 99.85%, 92.28% and 95.57%, respectively. In conclusion, the average of accuracy for all categories is 91.26%. The experiment using the voice of male-teenagers gives the worst accuracy, which is caused by the overlapping frequencies of voice in children, teenagers and adults.
Keyword: Voice identification, PNN model, MFCC, Age-identification, Gender-identification