Judul: Perbedaan Kandungan Senyawa Resin Gaharu (Aquilaria malaccensis) Hasil Inokulasi pada Tingkat Semai dan Pohon
Abstrak: Agarwood is one of forest tree species that can be harvested for its timber and resin, which has high price. One of agarwood tree species which has ability to form agarwood with the high-quality is Aquilaria malaccensis. Information on chemicals contained in agarwood is important for the development of this product that research on chemical content of agarwood resin needs to be done. The purpose of this research is to observe changes in resin components of agarwood inoculated with agarwood inducing fungi. Induction of Fusarium solani and Fusarium oxysporum fungi was done on the stem of A. malaccensis seedlings and trees, and then the chemical components of their resins were analyzed using GCMS. The result showed that all treatments were successfully induced agarwood formation. There are 7 main chemical compounds of agarwood produced by F. solani inoculated seedlings with relative concentrations of 16.38% for isolates from Jambi, and 13.87% for isolate from Gorontalo. Innoculation of F. oxysporum on trees generated 10 agarwood main compounds with relative concentration of 13.06%.
Keyword: Fusarium oxysporum, Fusarium solani, Aquilaria malaccensis, agarwood resin derivatives

Judul: Peranan Zat Ekstraktif Dalam Pembentukan Gaharu Pada Aquilaria crassna Pierre ex Lecomte dan Aquilaria microcarpa Baill
Abstrak: This research is aimed at investigating the anti fungal activity (AFA), the correlation of gaharu tree’s phenolics in relation with the susceptibility of the trees to Fusarium bulbigenum attack in the formation of agarwood, and to observe total phenolics content and tree’s chemicals of Aquilaria crassna and Aquilaria microcarpa pre-inoculation, the reology of tree’s chemical and microorganism change along inoculation time. There were variations of anti fungal activity among trees, and the highest is at tree no. 10 that AFA was in the middle class (39,77%), but entirely agarwood trees exhibited a low anti fungal activity at lab scale. Further fractionation and bioassay showed that the most active component are likely in the ethyl acetate fraction that exhibited strong anti fungal activity at 4% concentration. Trees as many as 20 of A. microcarpa at Carita and 10 of A. crassna at Darmaga were inoculated with isolate of F.bulbigenum in spiral pattern around the stem. Prior to inoculation, strips were taken from the stem for total phenolics content and chemicals analyzing. The result revealed that total phenolics content and infection area exhibited a negative correlation, which means the higher the phenolics content, the smaller the infection area. The preinoculation chemicals analysis showed that tree with smaller infection area had larger type of compounds and higher concentration of phenolics than tree with wider one. Some chemicals that at certain plants acted as defense system, according to some references, were found at higher concentration in the gaharu trees with smaller infection or they were not even traced in other tree. The reology analysis revealed that the largest types of compounds were noticed at three day’s old inoculation. Agarwood constituents and other aromatic compounds were detected since three days after inoculation which is indicated the agarwood formation was taken place. Meanwhile, the microbiology analysis showed there was no microbes change in the inoculation sites along 6 month inoculation time, but some small insects, such as ants and bugs, were found at the area.
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Judul: Dynamical System of Hepatitis B in Three Groups with Vaccination
Abstrak: The aim of this study is to modify the hepatitis B transmission model in three age groups involving vaccination from the model conducted by Zhoe and Zhang.The method used is to analyze the stability of the fixed point and its basic reproduction number (R_0). Performed stability analysis and numerical simulation to see population dynamics. Next, a sensitivity analysis of the parameters was carried out to see its effect on R_0. From the analysis obtained two fixed points, namely non-endemic and endemic fixed points. Non-endemic fixed points are locally asymptotically stable if R_0 <1 Meanwhile, the endemic fixed point is locally asymptotically stable if R_0 > 1. Hepatitis vaccination affects the number of susceptible population, because the more successful the vaccination, the smaller the number of susceptible populations so that the smaller the population will be infected.
Keyword: Dynamic, Hepatitis B, Vaccine, Mathematical model