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"Desalination is a way to process sea water with a high salinity level, which makes water non-consumable. Various desalination technologies, such as distillation, vapor compression, and reverse osmosis, have been developed but require energy and large financial investments. Microbial desalination cell (MDC) is a modified desalination technology of a microbial fuel cell that can remove salt content in water with the help of microorganisms through organic matter degradation. This research used Debaryomyces hansenii to degrade organic material in the anode chamber. The ratio of the volume chamber, the volume ratio of culture:substrate, and the volume progression of the culture and substrate were evaluated in terms of salt removal and electricity generation. This research shows that MDC using a 9:1:9 ratio of the volume chamber, a culture:substrate ratio of 2:3 (v/v), and a volume progression of the culture and substrate of 1.5 times gave the best desalination performance: a salt removal level of 55.03%"

"Xilitol merupakan gula alkohol jenis pentitol, yang jalur metabolismenya tidak dipengaruhi oleh insulin, serta memiliki aktivitas anti kariogenik. Produksi xilitol dengan cara fermentasi dinilai lebih ekonomis dan praktis dibandingkan dengan cara lainnya. Salah satu khamir yang memiliki potensi besar untuk fermentasi xilitol adalah Debaryomyces hanseniii osmotoleran. Proses reduksi xilosa menjadi xilitol dikatalisis oleh xilosa reduktase (XR), sedangkan proses oksidasi xilitol menjadi xilulosa dikatalisis oleh xilitol dehidrogenase (XDH). Pada penelitian sebelumnya, telah dilakukan pre-treatment kondisi osmotik tinggi pada khamir D. hansenii, namun ternyata kemampuan biokonversi khamir tersebut masih rendah, sehingga dibutuhkan cara untuk meningkatkan aktivitas biokonversinya. Salah satu upaya untuk meningkatkan aktivitas biokonversi khamir D. hansenii adalah dengan mutagenesis menggunakan etil metan sulfonat sebagai mutagen kimia. Inkubasi mutasi dilakukan selama 20, 45, dan 60 menit pada suhu 30oC dan kecepatan pengadukan 70 rpm. Mutan auksotrop diisolasi dengan media minimum, kemudian mutan yang diperoleh diuji nilai aktivitas XR dan XDH-nya. Hasil terbaik ditunjukkan oleh mutan EMS 60 (waktu inkubasi mutasi 20 menit), dengan nilai uji aktivitas XR tertinggi yang disertai dengan nilai uji aktivitas XDH terendah.

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Xylitol is a sugar alcohol, pentitol type, not affected by the metabolic pathway of insulin and also have anti-cariogenic activity. Xylitol production by fermentation process is prefered, because this process is more economical and simple. One of the potential yeast for xylitol fermentation is Debaryomyces hanseniii osmotolerant. The reduction process of xylose to xylitol is catalyzed by xylose reductase (XR), whereas the oxidation process from xylitol to xylulose catalyzed by xylitol dehydrogenase (XDH). In the previous experiment, a pre-treatment of high salt concentration has given to Debaryomyces hansenii, but the bioconversion activity is still low, so we need some modification to increase the bioconversion activity. One method to increase the bioconversion activity of D. hansenii is to perform mutagenesis using ethyl methane sulphonate as a chemical mutagen. Incubation mutation done for 20, 45, and 60 min at 30°C and at 70 rpm stirring speed. Auksotrop mutants were isolated with minimum media, then the XR and XDH activity of the mutants were tested. The best result was shown by the A mutant (mutations incubation time 20 minutes), with the value of the highest XR enzyme activity and the lowest XDH enzyme activity."

"Penelitian bertujuan membuat pollen substitute (PS) yang disukai dan dapat meningkatkan produktivitas lebah madu A. cerana. Pollen substitute dibuat dengan bahan dasar tepung kedelai dan susu skim. Pada penelitian ini A.cerana diberikan tiga macam pollen substitute, yaitu PS A (mengandung bahan dasar, Debaryomyces hansenii CR133, madu); PS B (mengandung bahan dasar, sirup gula); PS C (mengandung bahan dasar, madu). Pemberian PS selama 20 hari, dan lebah dibiarkan mencari serbuk sari dan nektar di alam. Koloni kontrol tidak diberi PS. Hasil penelitian menunjukkan bahwa PS yang dibuat memenuhi kriteria sebagai PS yang baik. Apis cerana menyukai PS A dan PS C dengan tingkat konsumsi yang lebih tinggi dibandingkan PS B. Pemberian semua jenis PS meningkatkan keliling (0,3--4,5 cm per hari) dan jumlah honeycomb. Pada kontrol terdapat kenaikan keliling honeycomb (0,2--0,5 cm per hari), namun tidak ada penambahan jumlah honeycomb. Secara umum, lebah pekerja yang diberi PS dan kontrol mengalami kenaikan berat badan (5--56,94%).

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The research aimed to make pollen substitutes preferred by and increase the productivity of A. cerana. Basic ingredients of pollen substitutes (PS) were soy flour and skim milk. There were three types of pollen substitutes, i.e. PS A (contained basic ingredients, Debaryomyces hansenii CR133, honey); PS B (basic ingredients, sugar syrup); and PS C (basic ingredients, honey). The pollen substitutes were fed to colonies of A. cerana for 20 days, but they were allowed to forage on flowers. No PS was given to the control colonies.

The results showed that A. cerana preferred PSA and PS C to PS A. Increases of circumference and number of honeycombs were observed in colonies fed with all types of PSs (0,3--4,5 cm/day). There was an increase of the circumference of honeycombs in the control (0,2--0,5 cm/day), but there was no addition of new honeycomb. Generally, the weight of individual worker bees increased in colonies fed with PSs and control (5--56,94%)."