Judul: Xylooligosaccharide production of corncobs as prebiotic candidate by high temperature heating and enzymatic hydrolysis.
Abstrak: Corncob waste is a rich xylan source that can be utilized as raw material for xylooligosaccharides (XOS) production. XOS is a potential prebiotic and has high economic value. Two corn varieties i.e. Bisi and Pioneer were first analyzed for its hemicellulose, cellulose and lignin contents and xylan yield to choose the corn variety to be studied. Process technology for XOS production was studied using available equipment such as oven. Xylooligosaccharide (XOS) from corncob was produced in two stages i.e. xylan extraction by heating at high temperatures in oven or autoclave as comparison, followed by enzymatic hydrolysis. Analysis of two corncob varieties showed that Pioneer variety contained higher hemicellulose content (34.98%) and xylan yield (18.32%) than Bisi variety (12.28% and 10.22%, respectively), therefore Pioneer variety was chosen as raw material for XOS production. Corncob particles were soaked in dilute acid (1 g/l H2SO4) for 12 h at 60 oC, filtered and washed with tap water and then heated in oven or autoclave. Before oven heating, The corncobs were added with water at various ratios (1:1 – 1:5) and then heated in oven at various temperature (130 oC, 140 oC, 150 oC for 0.5 h) and autoclave at 121oC for 0.5, 1, 1.5 and 2 h with one and two heating cycles. During heating, the total sugar and reducing sugar were increase, while the degree of polymerization was decrease. The results showed that heating in oven to extract the xylan was affected by the ratios of corncobs and aquadest and heating temperatures. Oven heating (130-150 oC) with optimum ratio of corncobs and aquadest (1:3) successfully increased the xylan content from 3.98% up to 18.21 – 19.46% while repeated heating cycle (two cycles) did not affect the xylan content. Heating the corncobs with aquadest (at the ratio of 1:3) in oven at 130 oC for 0.5 h produced 18.98% xylan and enzymatic conversion of the xylan by xylanase significantly increased the XOS content from 19.60% up to 44.06%. Heating the corncobs in autoclave (121 oC, 0.5 h) followed by enzymatic conversion produced higher XOS content (65.67%). The corncob XOS could stimulate the growth of Lactobacillus plantarum kik and Bifidobacterium longum ATCC 15707 by 1.2 until 1.7 unit log, indicating the prebiotic properties. Cookies prebiotic produced by addition of 5% (based on wheat flour) had higher hardness texture (1256 gf) than control without XOS (1067 gf).
Keyword: 

Judul: Kajian Hidrolisis Tongkol Jagung oleh Kapang Selulolitik Menggunakan Kultivasi Media Padat untuk Produksi Pakan
Abstrak: Corn (Zea mays L.) is one of the main food crops in the world. Most of corn use as raw material for food and non-food industries. But these applications are limited to the corn kernel, and other parts of corn plant were not utilized yet. Among the available agricultural products, corncob is an abundant lignocellulosic raw materials and potential sources for feed in Indonesia. Corncob utilization for feed has been conducted for years, although it is limited as fiber source. High amount of lignocellulosic compound affects low digestibility of corncob. Biological process can be used to improve the nutritional value corncob, which can impact to the feed availability during the dry season. The objective of this research was to improve the nutrition value of corncob through fungal cellulolytic hydrolysis by using solid-state cultivation. Trichoderma viride and Rhizopus oryzae were used as fungal cellulolytic microorganisms which were cultivated in different bed thickness (2 and 4 cm) and mixing treatment (intermittent mixing every 3 days, and no mixing). Inocula were prepared from 7 days-old of fungi slant and grown on rice bran flour for 10 days. The process was conducted for 15 days, and the cultures were monitored every 3 days. The changes on chemical composition (moisture, fiber, protein, reducing sugar, and total sugar), pH value, and loss weight of the substrate. In the final cultivation, the products were analyzed as in vitro digestibility, the changes of fiber structure by using microscopic examination. T. viride caused low moisture content (10%) remained on the substrate in the end of cultivation; while in inverse fact was to R. oryzae (91%). Cellulolytic enzymes acts on corncob accumulated the total and reducing sugar content, and produced cello-oligosaccharides which functioned as prebiotic for ruminant animal. In vitro digestibility of the products from both fungal, bed thickness and mixing treatments also showed insignificantly effects. Since it was very long cultivation process caused the available nutritional value were re-used for fungal metabolism.
Keyword: 

Judul: Persepsi Remaja Terkadap Kehidupan Rumah Tangga Dan Faktor-Paktor Yang Mempengaruhinya (Sebuah Analisis Jender)
Abstrak: Masalah jender oleh kaum feminis digunakan dalam menganalisis masalah sosial dan nierekontruksi sosial budaya sebuali masyarakat. Budaya patriarki dianggap telali menciptakan do~ninaslia ki-laki atas perempuan yang melahirkan bias jender (Handayani dan Sugiarti, 2001). Salah satu pemikir teoritis feminis awal, Jhon Stuart Mill dalam bukunya The Subjection Woman (1 869) tnengkritik pekerjaan perempuan di sektor domestik sebagai pekerjaan irasional, emosional dan tiranis (Megawangi, 1999). Penelitian ini bertujuan untuk mengetahui persepsi remaja terhadap peran jender dalam kehidupan rumah tangga dan faktor-faktor yang signifikan mempengaruhi persepsi tersebut. Hasil analisis CHAID menunjukkan bahwa faktor yang paling signifikan mempengaruhi peubah respon adalah jenis kelamin, tingkat pendidikan, kegiatan terbanyak, dan provinsi. Sedangkan status perkawinan dan asal daerah tidak muncul sebagai faktor yang signifikan. Remaja yang setuju terhadap peran jender dalam kehidupan mmah tangga sebanyak 6382 orang (79%) dan 1696 orang (21%) tidak setuju. Persentase responden perempuan yang setuju terhadap peran jender lebih tinggi dari pada laki-laki yaitu 85,36% sedangkan laki-laki 72,80%. Peubah jenis kelamin membagi responden ke dalam dua kelompok, yaitu laki-laki dan perempuan. Interaksi antara peubah jenis kelamin dengall-peubah tingkat pendidikan menghasilkan konsekuetisi tidak bisa disamakan interpretasi antara responden laki-laki dengan responden perempuan. Baik pada laki-laki maupun perempuan dapat diketahui bahwa semakin tinggi tingkat pendidikan maka persentase yang setuju terhadap peran jender semakin menurun. Hal ini menunjukkan bahwa pendidikan memiliki pengaruh yang cukup besar dalam membentuk atau merubah persepsi remaja terhadap peran jender.
Keyword: