Judul: Produksi Kolagenase dari Isolat Bacillus licheniformis F-11.1 dan F-11.4
Abstrak: Hydrolysis by collagenase enzyme could increase nutrition and function of food proteins. This research was conducted to produce collagenase enzyme from Bacillus licheniformis F-11.1 and F- 11.4. B. licheniformis isolate F-11.1 and F-11.4 were cultured in three types of production media, which is Luria Bertani (LB) media consisted of 5% collagen (LBC), 50% LB media consisted of 5% collagen (LBHC), and 5% collagen (CLG). The activity of collagenase, protein content, and cell turbidity of B. licheniformis F-11.1 and F-11.4 were measured every 5 hours during 50 hours incubation. The result showed that optimum collagenase production of B. licheniformis isolate F- 11.1 was reached in LBC and LBHC media with activity of 2,057 U/mg and 2,037 U/mg, respectively. Optimum collagenase production of B. licheniformis isolate F-11.4 was reached in LBC media with activity of 4,695 U/mg. Isolate F-11.4 in LBHC media possesed the optimum collagenase activity of 2,811 U/mg. CLG media gave optimum collagenase activity of B. licheniformis F-11.1 and F-11.4 at 0,807 U/mg and 0,306 U/mg respectively. These research concluded that LBC and LBHC media was the best choice for collagenase production of B. licheniformis F-11.1 and F-11.4.
Keyword: 

Judul: Zimogram aktivitas kolagenase dari bacillus licheniformis F-11.1 dan F-11.4.
Abstrak: Bacillus licheniformis F-11.1 and F-11.4 are strains from B. lichniformis F-11 were isolated from shrimp shell waste in Palembang, Indonesia. They has poliglutamat acid mutation in the operon (PGA) and chitinase AB, so it doesn’t have chitinase activity, but high protease activity. Collagenase plays an important role in the softening of meat and the wound healing process. Precipitation enzyme can use ammonium sulfate to stabilize the enzyme, therebly reducing protein denaturation. Zimogram is an electrophoresis technique to determine the activity of an enzyme in situ and qualitative results of the gel electrophoresis. This research was conduct to analyze the activity Bacillus licheniformis F-11.1 and F-11.4 collagenase qualitatively using techniques zimogram. Analysis is performed on both isolates that grown in three growth media, ie LB + 5% collagen (LBC), ½ LB + 5% collagen (LBHC), and 5% collagen (CLG). Bacillus licheniformis F-11.1 and F-11.4 produce collagenase in the three growth media were added collagen as the substrate growth. Cell growth both isolates best on LBC media. Zimogram showed B. licheniformis F-11.1 and F-11.4 produce collagenase. It shown by the formation of clear zone on the gel due to degradation of collagen by collagenase. Isolates B. licheniformis F-11.1 produce the highest fraction of enzyme crude extract derived from LBC media is 32 fraction. Meanwhile isolates B. lichniformis F-11.4 produce the highest fraction of crude extract derived from LBHC media is 37 fraction
Keyword: 

Judul: Alat Perekam Data Hujan dengan Mode Hemat Daya
Abstrak: Pengukuran intensitas hujan dapat dilakukan dengan beberapa pendekatan, seperti menggunakan perekam data hujan otomatis (automatic rain recorder). Data curah hujan yang terukur oleh tipping bucket akan tersimpan dalam SDcard setiap kejadian hujan terjadi. Penggunaan arduino sebagai komponen utama dipilih karena perangkat open source yang mudah dimodifikasi. Beberapa komponen arduino yang dapat dimodifikasi adalah ATmega dengan konsumsi daya sebesar 12 mA pada 3 volt serta 17 mA pada 5 volt. Adapun FTDI mengkonsumsi daya sebesar 20 mA pada 5 volt. Voltage regulator mengkonsumsi daya sebesar 38 mA pada 5 volt, 64 mA pada 9 volt, 103 mA pada 12 volt, selain itu led mengkonsumsi 1 mA pada 5 volt. Komponen yang dapat dihilangkan pada arduino antara lain FTDI, voltage regulator, serta led. Pengurangan komponen ini bertujuan agar daya tahan baterai menjadi 6.5 kali lebih hemat dibandingkan arduino standar. Setelah bagian bagian tersebut dihilangkan maka total konsumsi daya yang diperlukan oleh mikrokontroler on board arduino adalah 12 mA saat 3 volt dan 17 mA saat 5 volt saat mode kerjanya. Hasil pengujian menunjukkan bahwa pada penggunaan mode sleep lebih efisien daya dibandingkan mode power save. Mode sleep membantu cara penghematan daya pada pembuatan alat perekam data hujan Penggunaan metode ini jika diasumsikan kejadian hujan hanya terjadi selama tiga jam dalam sehari maka dengan menggunakan baterai sebesar 400 mAh dengan tegangan 3 volt maka alat perekam data hujan ini dapat hidup selama 15 Hari….
Keyword: Arduino, Power save, Rain, Automatic recorder, Tipping bucket, Geophysics and Meteorology, Rain fall, Model penakar hujan, Arduino promini, Arduino uno