Curcumin nanoemulsion which has a particle size of 20-200 nm, is one of the curcumin drug delivery system that can increase curcumin solubility and bioavailability. The previous method of curcumin nanoemulsion formulation is modified thin-film hydration followed by sonication that has a long process and using organic solvent. This study aims to make curcumin nanoemulsion by wet ball milling method in soybean oil – Tween 80 system. Nanoemulsion is expected to have smallest particle size, high curcumin loading capacity and good stability during storage. Preparation of curcumin nanoemulsion is done by wet milling method which consists of curcumin as drug, soybean oil as curcumin solvent, tween 80 as stabilizer, water as dispersed medium and milling beads as milling media on the vial with various milling time. Particle size and polydispersity index are monitored using dynamic light scattering while nanoemulsion morphology is observed using digital imaging microscope. Results show that optimum milling times is 24 h and the highest curcumin added which produces less than 500 nm particles is 300 mg which is stable during 60 days of storage. Particle size of the nanoemulsion is ranging from 127 – 338 nm. In addition, wet ball milling methods is relatively simple and easy to apply.

Bacterial cellulose can be modified by esterification using palmitic acid and Mucor miehei lipase as catalysts. The purpose of this research was to determine the optimum conditions of esterification reaction of cellulose and palmitic acid. The esterification reaction was carried out at the time variation of 6, 12, 18, 24 and 30 hours and the mass ratio of cellulose: palmitic acid (1:1, 1: 2, 1: 3, 1:4, 1:5, 1:6) at 50°C. The cellulose palmitate was examined its physical and chemical properties by using FTIR spectrophotometer, XRD, bubble point test and saponification apparatus. The results showed that the optimum reaction time of esterification reaction of cellulose and palmitic acid occurred within 24 hours and the mass ratio of cellulose: palmitic acid was 1:3 resulting in DS of 0.376 with swelling index of 187%, crystallinity index of 61.95%, and Φ porous of 2.40 μm. Identification of functional groups using FTIR spectrophotometer showed that C=O ester group was observed at 1737.74 cm-1 and strengthened by the appearance of C-O ester peak at 1280 cm-1. The conclusion of this study is reaction time and reactant ratio influence significantly the DS of cellulose ester.

Curcumin has various bio-functional properties; however, curcumin poor bioavailability reduces its efficacy. Nanoemulsion delivery system is an alternative method improving curcumin bioavailability in which surfactant and oil used, play an important role in determining nanoemulsion properties. Several studies on curcumin nanoemulsions apply synthetic surfactants which can be harmful if they are added excessively. This study aims to use a natural emulsifying agent, namely okra mucilage extract (OME), and determine its effectiveness as co surfactant. OME is safe to use as an emulsifying agent because it is natural, harmless, safe, biodegradable and eco-friendly. Liquid-liquid and microwave extraction methods were used to obtain OME which was further identified using Fourier Transfer Infrared Spectroscopy (FTIR). Meanwhile, sonication method was used to produce curcumin nano-emulsion (CurN). The particle size and polydispersity index of curcumin nano-emulsion were measured using Particle Size Analyzer (PSA) with Dynamic Light Scattering (DLS) technique, while the morphology of the nanoemulsion was observed using a Digital Imaging Microscope and Confocal Laser Scanning Microscope (CLSM). The results showed that the addition of 0.0160 g OME at a ratio of 1:5 (OME: Tween 80) in the preparation of 5 mL of CurN was able to reduce the particle size and polydispersity index from 740.80 ± 9.70 nm to 289.20 ± 2.23 and 0.340 ± 0.005 to 0.165 ± 0.008 respectively. OME increased the encapsulation efficiency from 77.93 ± 6.59% to 87.17 ± 1.12% which was confirmed by the augmentation of the fluorescence intensity of curcumin from 192.82 to 388.55. The addition of OME also maintained the stability of the CurN up to 14 days of storage at 4°C.

Modification of bacterial cellulose through enzymatic esterification between cellulose and propionic acid has been carried out to produce cellulose propionate as a raw material of dialysis membrane. The research aimed to characterize of cellulose propionate and assess its potency as raw material for a membrane. The esterification was performed for 8 hours at 50 ⁰C with cellulose and propionic acid in the mass ratio of 1:5. The physical-chemical properties of resulted cellulose propionate were determined for their functional group using FTIR, crystallinity index by XRD, swelling index by gravimetric method, specific gravity, maximum pore size diameter and membrane thickness. The cellulose propionate showed peak absorbance at the wave number of 1743 cm-1 from C=O absorption and 1108 cm-1 and 1037 cm-1 from CO absorption with the degree of crystallinity of 61.56% and density of 1.39 g/cm3. Cellulose propionate membrane has a maximum pore size of 2.25 ± 0.04 µm and thickness of 0.029 ±0.001mm, the swelling index of 153%. Diffusion equilibrium of uric acid was 3 hours at average diffusion rate of 1.48ppm/h.