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Pyridine and its derivatives are important compounds with tremendous applications. Pyridine derivatives, such as aminopyridine, have been widely investigated concerning their biological activity. It is reported that generally biological activities of the compound increased after complexation. Tetrakis-2-amino-5-methylpyridinecopper(II) chloride pentahydrate has been synthesized facilely in less than five minutes. It was formed by mixing CuCl2-2H2O and 2-amino-5-methylpyridine in 1:4 mole ratio in ethanol at room temperature. The complex was characterized to determine its proposed empirical formula and the structure. The forming of the complex was indicated by shifting of maximum wavelength (Amax) of UV-Vis spectra towards smaller than CuCl2-2H2O from 850 nm to 675 nm. Atomic Absorption Spectroscopy (AAS) measurement showed the content of copper to be 9.63 % corresponding to the theoretical value of copper content in Cu(2-amino-5-methylpyridine)4Cl2(H2O)x (x= 4, 5, or 6). Thermogravimetric Analysis and Differential Scanning Calorimetry (TGA-DSC) showed a mass reduction of 13.02 % which was equivalent to the evaporation of five molecules of lattice water. The cation and anion charge ratio of the complex was 2:1. This four coordinated-complex was paramagnetic with an effective magnetic moment of 1.83 BM. The proposed empirical formula of the complex was [Cu(2-amino-5-methylpyridine)4]Cl2-5H2O.

<p>The addition of garlic powder to gelatin from chicken claw waste was potentially developed as a natural preservative in food, especially for meat. Preparation of gelatin/garlic biocomposite was performed in three stages: synthesis of gelatin from chicken claw, garlic powder preparation as allicin source and preparation of biocomposite gelatin/garlic. The preparation of dry biocomposites was done by weighing the gelatin and garlic powder in weight ratio of 1 : 1 and 1 : 2 (w/w) in the total mass of 0.75 grams. For wet biocomposite preparation, the mixture of the powder was solved in 5 mL of lactic acid 2 %. Functional groups of gelatin, garlic and biocomposite were analyzed by <em>f</em><em>ourier transform infrared spectroscopy</em> (FTIR). The antibacterial activity of biocomposite against <em>Staphylococcus aureus</em> were tested using disc diffusion method. This test was performed on garlic powder, solvent and gelatin/garlic biocomposites powder in the ratio of 1 : 1 and 1 : 2 in 2 % lactic acid solvent. The biocomposite with a weight ratio of gelatin : garlic of  1 : 1 had the optimum diameter of inhibition zone. The effectiveness of biocomposite gelatin/garlic as natural preservative applied in meat was also physically studied by organoleptic analysis. Organoleptic analysis through the hedonic test was conducted on the parameters of color, smell, and texture of gelatin/garlic biocomposites-coated meat. The results showed that the addition of garlic can increase the effectiveness of gelatin as a natural preservative of meat for four days stored in closed packaging at room temperature.</p>

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