Judul: Pengaruh asam salisilat terhadap sifat kayu gaharu (Aquilaria crassna)
Abstrak: Salicylic acid is one of secondau signal molecule for the formation of secondary metabolites, that has a role as defense substance. The role of salicylic acid on the formation of agarwood is not yet known. The indicator of the agar formation is the modification of the wood characteristic such as wood discolouration.Wood discolouration may occur due to terpenoid accumulation. This research was carried out to determine the role of salicylic acid on the modification of wood characteristic interm of discolouration and te~penoida ccumulation of A. oassna. The bark and cambial layers of branches of 8 years A. crassna tree were peeled off about 2 cm long, then smeared with salicylic acid at 100mM (SA loo), 200mM (SA 200), 3001nM (SA 300), 400mM (SA 400), 700mM (SA 700) and IOOOmM (SA 1000). The level of wood colour intensity and the area of colour formation, accu~nulation of terpenoid (histochemical and Lieberman-Burchard analyses) and fiagrance level was observed at 5, 10, 25 and 50 days after application of salicylic acid (daa). The application of salicylic acid caused wood discolouration from white to brownish white, physiological symptoms such as chlorosis (SA 400 at 50 daa and SA 700 at 5 daa), wood brittleness and death of some branches (SA 700 at 25 daa and SA 1000 at 5 daa). Histochemically, the accumulation of terpenoid was found in parenchyma rays, included phloem, xylem vessel and pith of treated branches with SA 100, SA 200, SA 300 and SA 400. For those treated with SA 700 and SA 1000, terpenoid was found only in parenchyma rays and xyleni vessel. Accutnulation of lipid was found in parenchyma mys, included phloem and xylenl vessel of all treated branches. Whereas the accu~nulation of starch was found in parenchyma rays and included phloem on all treated branches at 5-10 daa. Yellowgreen the Liebennan-Burchard analysis indicated that terpenoid in the forin of sterol was formed in the heated wood. Salicylic acid can not induce fiagrance formation.
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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