Judul: Pemurnian Glukomanan secara Enzimatis dari Tepung Iles-iles
Abstrak: Glucomannan is typical polysaccharide derived from konjac tuber. Conventional fractionation of glucomannan in konjac flour is by mechanical separation method, but it produces low purity glucomannan flour and needs further purification methods. This research is explored the glucomannan purification by enzymatic hydrolysis directly from konjac flour. Since konjac flour mainly consisted of starch, glucomannan and fiber, in this research sole thermophilic α-amylase enzyme and consortium of enzymes (amylase, xylanase and cellulose) were applied on 50 and 65 oC of incubation temperature for 2 hours. The results showed that consortium of enzymes can not be used for glucomannan purification; because glucomannan component is hydrolyzed by xylanase and cellulose. Glucomannan flour produced from sole α-amylase with incubation temperature of 50ᵒC has the highest yield (42.7%) compared to incubation temperature of 65ᵒC (31.6%). Duration of incubation also influenced to the glucomannan yield, and two hours of incubation time gave the best glucomannan flour with highest yield (37.0%), purity (46.1%), viscosity (42.3 cPs) and good whiteness (12.7%). Enzymatic hydrolysis of konjac flour also produced starch syrup (DE 55.6 – 77.9) as by- products.
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Judul: Pemurnian Glukomanan secara Enzimatis dari Tepung Iles-iles
Abstrak: Glucomannan is typical polysaccharide derived from konjac tuber. Conventional fractionation of glucomannan in konjac flour is by mechanical separation method, but it produces low purity glucomannan flour and needs further purification methods. This research is explored the glucomannan purification by enzymatic hydrolysis directly from konjac flour. Since konjac flour mainly consisted of starch, glucomannan and fiber, in this research sole thermophilic α-amylase enzyme and consortium of enzymes (amylase, xylanase and cellulose) were applied on 50 and 65 oC of incubation temperature for 2 hours. The results showed that consortium of enzymes can not be used for glucomannan purification; because glucomannan component is hydrolyzed by xylanase and cellulose. Glucomannan flour produced from sole α-amylase with incubation temperature of 50ᵒC has the highest yield (42.7%) compared to incubation temperature of 65ᵒC (31.6%). Duration of incubation also influenced to the glucomannan yield, and two hours of incubation time gave the best glucomannan flour with highest yield (37.0%), purity (46.1%), viscosity (42.3 cPs) and good whiteness (12.7%). Enzymatic hydrolysis of konjac flour also produced starch syrup (DE 55.6 – 77.9) as by- products.
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Judul: Karakteristik Suara Song Burung Kenari (Serinus canaria) Postur Besar dan Kecil.
Abstrak: Burung kenari (Serinus canaria) memiliki nyanyian yang sangat bervariasi dengan durasi yang panjang dan merupakan tipe burung bernyanyi open learners. Penelitian ini bertujuan menganalisis karakteristik suara song burung kenari (Serinus canaria). Penelitian dilakukan pada bulan April sampai Juni 2017 di Bogor, Jawa Barat. Perekaman suara song terhadap 12 ekor burung kenari jantan dilakukan dengan menggunakan mikrofon Sennheiser ME66 dan alat perekam Sony PCM-D50. Burung kenari yang digunakan merupakan burung yang pernah mengikuti kontes burung kicau dan memiliki predikat juara kontes burung. Amplitudo, durasi suara, frekuensi, dan volume suara burung dianalisis dengan menggunakan software Raven Pro 1.4. Data tersebut selanjutnya dianalisis deskriptif. Hasil analisis suara menunjukkan bahwa burung kenari memiliki banyak syllable, suara song rapat dan tidak terputus-putus, tempo yang cepat, dan adanya pengulangan suku kata pada setiap suara song. Burung kenari postur kecil memiliki rataan durasi lebih panjang dibandingkan dengan kenari postur besar, tetapi burung kenari besar memiliki rataan max amplitudo, average power, max power, min amplitudo, peak amplitudo, dan peak frekuensi.
Keyword: karakteristik suara (song), kenari, syllable