Judul: Antiyeast activities of cumin oil (Cuminum cyminum) toward osmophilic yeast strains isolated from high sugar food
Abstrak: The antiyeast activities of cumin oil toward osmophilic yeast strains isolated from high sugar food were studied. Sixty-eight osmophilic yeasts were isolated from sample i.e. strawberry jam (26 isolates), pineapple jam (25 isolates), and South Sumatera honey (17 isolates). No yeast was obtained from condensed milk, Sumbawa honey, sweet soy sauce, and palmsugar. These yeast isolates were identified based on sequence analysis of the ITS region as Candida metapsilosis, C. parapsilosis, C. orthopsilosis, C. etchellsii and Sterigmatomyces halophilus. Phylogenetic analysis showed that most of the osmophilic yeasts (67 out of 68 isolates) were located in the phylum Ascomycota and only 1 isolate was located in the phylum Basidiomycota. Candida etchellsii was the predominant species in South Sumatera honey, while C. metapsilosis, C. parapsilosis, C. orthopsilosis were predominant species in jam. In both jam and honey samples C. metapsilosis and C. parapsilosis were found, whilst C. orthopsilosis was found only in pineapple jam. All five identified yeast species were used further to examine the antiyeast activities of cumin oil. Cumin oil was analyzed by GC-MS, and it was consisted of some compound i.e. cuminaldehide (35.44%), ρ-cymene (34.77%), β-pynene (15.08 %), γ-terpinene (8.15%), α-thujene, α-pinene, trans-limonene, cis-limonene, pentylcyclohexane, cyclohexane, and apiole. The examination of antiyeast activity based on disc agar diffusion method showed that all of the tested yeasts were sensitive to cumin oil.
Keyword: Cuminum cyminum

Judul: Antitoxin Activity of Ethanol Extract of Clove (Syzygium aromaticum)
Abstrak: Senyawa toksin dapat menginduksi terbentuknya radikal bebas (reactive oxygen species, ROS) yang dapat memicu kerusakan dan penurunan viabilitas sel. Cengkeh (Syzygium aromaticum) merupakan salah satu tanaman Indonesia yang mengandung senyawa fenolik sehingga memiliki aktivitas antioksidan yang dapat menurunkan toksisitas ROS. Namun, pengetahuan aktivitas antitoksin ekstrak cengkeh masih belum tersedia. Oleh karena itu, penelitian ini bertujuan mengetahui pengaruh ekstrak cengkeh sebagai agen antitoksin dengan menggunakan khamir Saccharomyces cerevisiae sebagai model. Senyawa toksin yang diujikan adalah mutagen malachite green. S. cerevisiae banyak digunakan sebagai organisme model untuk mengeksplorasi mekanisme seluler organisme tingkat tinggi karena homologi genetik dan fisiologinya. Ekstrak cengkeh diperoleh dari bunga dan daun dengan metode maserasi. Kandungan fenolik dalam ekstrak cengkeh dianalisis dengan metode Folin-ciocalteu. Metode yang digunakan untuk menganalisis kemampuan ekstrak cengkeh sebagai agen antitoksin adalah uji dekolorisasi dan uji viabilitas sel. Kandungan fenolik ekstrak daun dan bunga cengkeh masing-masing adalah 441,28 dan 394,73 mg GAE g-1 ekstrak. Penambahan ekstrak mengurangi kemampuan S. cerevisiae mendekolorisasi malachite green tetapi meningkatkan viabilitas sel. Menariknya, koloni petite khamir ditemukan pada S. cerevisiae yang diberi konsentrasi tinggi ekstrak cengkeh. Hal ini mengindikasikan potensi ekstrak cengkeh dalam meregulasi aktivitas mitokondria. Penelitian lebih lanjut di level molekuler diperlukan untuk mengetahui mekanisme ekstrak cengkeh sebagai agen antitoksin., Toxic compounds can induce the formation of free radicals (reactive oxygen species, ROS) which can trigger damage and decrease cell viability. Clove (Syzygium aromaticum) is one of the Indonesian plants that contain phenolic compounds that are useful as antioxidants which can reduce ROS toxicity. However, little is known about the antitoxin activity of clove extract. Therefore, this study aimed to determine the effect of clove extract as an antitoxin agent using the yeast Saccharomyces cerevisiae as a model. The toxin compound tested is malachite green mutagen. S. cerevisiae is widely used as a model organism to explore the cellular mechanisms of higher organisms due to its genetic and physiological homology. Clove extract was obtained from bud and leaves using the maceration method. The compounds contained in cloves were analyzed by phenol quantitation using the folin-ciocalteu method. The methods used to analyzed the ability of clove extract as anti-mutagenic were decolorization test and cell viability test. The phenol content of leaves and bud extract were 441.28 and 394.73 mg GAE g-1 extract, respectively. The addition of extract reduced the ability of S. cerevisiae to decolorize malachite green but increased cell viability. Interestingly, number of petite colony of yeast was found in S. cerevisiae treated with high clove extract. This indicates the potential of clove extract in regulating mitochondrial activity. Further research at the molecular level is needed to determine the mechanism of clove extract as an antitoxin agent.
Keyword: Antitoxin, Clove, Phenolic, ROS, S. cerevisiae

Judul: Pengembangan Desain Sistem Pakar untuk Diagnosa Kerusakan alat Berat Bulldozer D375A-2
Abstrak: Alat berat adalah sarana untuk mempercepat proses pelaksanaan suatu pekerjaan yang sukar bahkan tidak mungkin dilakukan oleh manusia. Dalam penggunaan alat berat seringkali mengalami kerusakan·. Kerusakan yang terjadi mengakibatkan tertundanya pekerjaan yang sedang dilaksanakan. Untuk memperbaiki kerusakan memerlukan biaya dan waktu yang cukup lama agar alat berat tersebut dapat berfungsi kembali.
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