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"ABSTRAKInduksi dosis radiasi rendah memungkinkan terjadinya perubahan pada mekanisme sistem sellular dan molekuler, yang dengan kondisi tertentu, dapat memproteksi sel terhadap efek yang ditimbulkan oleh dosis radiasi tinggi yang diterima berikutnya. Fenomena demikian disebut respon radioadaptasi. Telah dilakukan penelitian respons adaptasi pada 80 ekor mencit jantan berumur 37 - 46 hari, dengan berat dalam rentang 23.79 ? 26.66 gram. Sampel mencit dibagi menjadi 4 kelompok, satu kelompok untuk kontrol sedangkan kelompok lainnya diberi perlakuan penyinaran dengan radiasi gamma Co 60, yang selanjutnya disebut perlakuan tanpa adaptasi, adaptasi I, dan adaptasi II. Pada perlakuan tanpa adaptasi, mencit diberi dosis challenges 1.0, 1.5, 2.0, 2.5, dan 3.0 Gy, perlakuan adaptasi I sampel mencit diberi dosis adaptasi 0.1 Gy sebelum kelima dosis challenges, dan perlakuan adaptasi II dosis kelima dosis challenges diberikan 5 menit setelah menerima dosis adaptasi 0.1 Gy. Jumlah leukosit rata-rata mencit kelompok kontrol (9.51 &lusmn; 0.81) x 103/μl. Umumnya pemberian radiasi pada ketiga perlakuan mengakibatkan jumlah lekosit menunun dan linier dengan kenaikan dosis. Penurunan jumlah leukosit tertinggi terjadi pada perlakuan tanpa adaptasi, kemudian diikuti oleh perlakuan adaptasi I dan perlakuan adaptasi II, dengan representasi koefesien linieritas -0.18, -0.15, dan -0.11.Ini menunjukkan bahwa respons adaptasi meningkat bila ada interval waktu antara pemberian dosis adaptasi dan dosis challenges. Selain respons pada leukosit, telah diteliti pula respons pada berbagai komponen leukosit, antara lain segmen neutrofil dan limfosit yang jumlahnya cenderung sedikit menurun seperti pada leukosit, serta eosinofil, neutrofil, neutrofil batang, dan monosit yang ternyata tidak memberikan perubahan respons yang signifikan pada ketiga perlakuan.

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ABSTRAKLow radiation dose induction might changes the mechanism of cellular and molecular system, with a certain condition; it can protect cells to reduce the effect from subsequent high dose. This phenomenon is called radioadaptive response. In this work radioadaptive response has been investigated to 80 male mice with the age from 37 to 46 days, and the weight from 23.79 to 26.66 grams. These samples were divided into 4 groups, one group was a control, and the other groups were treated with Co 60 gamma radiation which will be called as treatment without adaptive, adaptive I, and adaptive II. To the mice from the group of treatment without adaptive, challenge doses of 1.0, 1.5, 2.0, 2.5, and 3.0 Gy were delivered. The same challenge doses were given to the adaptive I and adaptive II treatment group after direct and 5 minutes receiving the adaptive dose of 0.1 Gy. The number of total leucocyt counts from the control group was (9.51 &lusmn; 0.81) x 103/μl. In general radiation doses decrease the leucocytes counts from the three treated groups and linearly related with the increasing dose. The effect of radioadaptive response of the adaptive II treatment group was relatively highter, which were illustrated by the linear coeffecient of the group without adaptive, adaptive I, and adaptive II with the value of -0.18, -0.15, and -0.11 repectively.These results indicated that the adaptive response increased when there was interval delivering time between adaptive and challenge dose. It was also found that components of leucocytes such as neutrophyl leucocytes and lymphocytes segments gave lower response with the trend likely the same as leucocytes. Furthermore there were no significant changes of response from the three types of treatment to other components such as eosinophyls, neutrophyl stems, and monocytes."

"Statin telah diketahui dapat menurunkan kandungan kolesterol dalamdarah. Statin menurunkan kandungan kolesterol dengan cara menghambatkefja enzim HMG Co-A reduktase yang dibutuhkan pada biosintesiskolesterol, Enzim tersebut mengkatalis reaksi perubahan p^iidrokshpmetilglutarilCo-A menjadi asam mevalonat. Statin biasanya dihasilkanmelalui fermentasi dengan menggunakan kapang jenis Aspergillus danMonascus. Akan tetapl, statin yang dihasilkan dari kapang Monascm tipeliar, kadamya masih relatif kecil. Untuk Itu dilakukan upaya peningkatangalur untuk mendapatkan galur yang leblh potensial dafem menghasilkanstatin. Jenis Monascus yang dipakal adalah Monascus purpumus. Upayapeningkatan galur dilakukan dengan mutasi sinar gamma (y) padabeberapa dosis irradiasi yaitu 0,1-0,5 kGy. Seleksl mutan dilakukansecara aoak trerdasarican pola penampakan koloni pada cawan petii dansetelah itu dipilih dosis optimum irradiasi (dosis yang memberikan persentasisurvival terkecil) berdasarkan jumlah koloni tunggal yang terbentuk. Dosisdosisoptimum yang didapatkan adalah 0,2 ; 0,3 dan 0,4 kGy. Fermentasiyang dilakukan terhadap Monascus purpureus tipe liar dan isolat-isolatnyatidak menunjukkan adanya statin. Beberapa senyawa yang diperkirakandihasilkan pada fermentasi dari isolat Monascus purpureus dan tipe liarnyaadalah pigmen warna monascin, monascorubrin, ankaflavin, sertarubropunctatin

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Statin has been known capable of reducing cholesterol content in

blood by inhibiting HMG Co-A reductase enzyme (an enzyme which is

needed in cholesterol biosynthesis). This enzyme catalysts the formation of

mevalonic acid from p-hydroxyl- p-methylglutaryl Co-A. Statin is usually

produced from the fermentation of AspergUlus and Monascus, but the statin

yield from the fermentation of Monascus wild type is still low. Therefore, it

needs strain improvement to increase the statin production which is done by

modifying the genetics. The strain used in this experiment Is Monascus

purpureus. The strain improvement is done by mutating Monascus purpureus

wild type using gamma (y) ray in several doses. The doses used in the

irradiation are 0,1; 0,2; 0,3; 0,4 and 0,5 kGy. Mutant selection is done

randomly based on the single colony pattern on petri dish. Before random

selection, the optimum doses of irradiation are needed to be determined. The

optimum doses are those which give the smallest survival fractions. Those

optimum doses are 0,2 kGy, 0,3 kGy and 0,4 kGy. Monascus purpureus wild

type and its isolates did not produce any statin under fermentation in Miyake's

medium. Several compounds which were predicted produced from

Monascus purpureus wild type and its isolates are monascin, monascorubrin,

ankaflavin and rubropunctatin"