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"Jerami padi merupakan salah satu limbah pertanian yang sangat melimpah di Indonesia. Jerami padi mengandung polisakarida dalam bentuk selulosa dan hemiselulosa, yang dapat dimanfaatkan sebagai bahan baku dalam produksi bioetanol. Penelitian ini bertujuan untuk melihat efektivitas produksi bioetanol dari sampel hidrolisat jerami padi dengan menggunakan ragi roti (ragi kering-Fermipan) dan ragi tapai (ragi padat-Sae). Penelitian dilakukan dengan memfermentasikan sampel menggunakan kedua jenis ragi tersebut dan isolat murni khamir Saccharomyces cerevisiae sebagai kontrol. Kadar glukosa diukur menggunakan glucometer dan kadar bioetanol dianalisis menggunakan high-performance liquid chromatography. Rancangan penelitian menggunakan Split Plot Design dengan dua faktor perlakuan; pemberian ragi (R) dan waktu fermentasi (T). Hasil penelitian menunjukkan bahwa kedua jenis ragi pada produksi kadar bioetanol dari sampel memberikan pengaruh yang tidak berbeda nyata; namun perlakuan Sae menghasilkan kadar bioetanol yang lebih tinggi dibandingkan dengan perlakuan Fermipan; laju produksi bioetanol pada perlakuan Sae juga lebih tinggi dibandingkan dengan laju produksi bioetanol pada perlakuan Fermipan. Kesimpulan dari penelitian adalah perlakuan Sae lebih efektif dalam memproduksi bioetanol dari sampel hidrolisat jerami padi.

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Rice straw is one of the most abundant agricultural waste in Indonesia. Rice straw contains polysaccharide in the form of cellulose and hemicellulose, which can be used as raw materials in the production of bioethanol. This study aims to examine the effectiveness of bioethanol production from rice straw‘s hydrolyzate using baker's yeast (dry starter - Fermipan) and tapai‘s starter (solid starter - Sae).

Research was carried out by fermenting the sample using two types of starters with a control of pure yeast Saccharomyces cerevisiae. Glucose level was measured by using glucometer and ethanol level was analyzed by using high-performance liquid chromatography. This study using Split Plot Design with two treatment factors; starter‘s inoculum (R) and time of fermentation (T).

The study shows that both types of starters has no significant difference on the bioethanol level production; however, Sae‘s treatment produced higher level of bioethanol compared to the Fermipan‘s; rate of bioethanol production at Sae‘s treatment is also higher than the rate of bioethanol production in Fermipan‘s. The conclusion of the study is Sae is more effective in producing bioethanol from rice straw hydrolyzate samples."

"Seiring peningkatan kebutuhan infrastruktur yang maju disertai penerapan ilmu pengetahuan dan teknologi yang berwawasan lingkungan, tidak dapat dihindari pembangunan konstruksi di atas lahan gambut. Penelitian ini bertujuan menganalisa nilai CBR dan nilai DCP tanah gambut daerah Kecamatan Kayu Agung, Sumatera Selatan pada kondisi unsoaked, terhadap penambahan mikroorganisme selulolitik potensial asli. Pada penelitian ini dilakukan metode pencampuran secara konvensional dengan alat penyemprot dengan volume pencampuran (satuan liter) sebanyak 10% dari berat tanah (satuan kg). Setelah dilakukan fermentasi selama 30 dan 45 hari terjadi peningkatan nilai CBR unsoaked dan penurunan nilai DCP unsoaked dari kondisi asli namun perubahan yang terjadi tidak signifikan.

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Along with the increase of advanced infrastructure needs and application of green science and technology, constructions on peatland is undeniable. This research aims to increase CBR value and to decrease DCP value for improving support capability of peat soil. Addition of potential cellulolytic potential microorganisms is a kind of natural solution for faster improvement on mechanical property of peat soil.

In this research, the mixing is conventionally by using sprayer with microorganisms volume as much as 10% of soil mass (in litre unit). After fermentation of 30 and 45 days, it shows increase of CBR value and decrease of DCP value from its initial condition yet the results obtained is still in bad condition."

"Di beberapa negara, perkembangan bioteknologi telah meluncurkan produk pangan yang dikenal dengan makanan kesehatan. Dimana mikroalga saat ini dapat dijual dalam bentuk kapsul atau di dalam makanan seperti aneka minuman dan pasta yang telah menunjukkan khasiat pengobatan dalam perlakuan kondisi seperti hiperkolesterolemia dan aterosklerosis. Penelitian ini bertujuan untuk mengetahui kadar protein pada mikroalga Botryococcus braunii dengan variasi spektrum cahaya tampak dengan metode Biuret. Hasil kadar protein untuk variasi spektrum cahaya tampak adalah dengan cahaya langsung 17,60 %, pemberian cahaya merah 13,48 % dan pemberian cahaya biru 11,82 %. Asam amino tertinggi yang dimiliki B.braunii baik sampel A, sampel B dan sampel C adalah Leusin/Leucine untuk asam amino esensial dan Alanin/Alanine untuk asam amino non esensial. Pada penelitian ini juga dapat didapatkan metode nilai kapasitansi lebih relevan dibandingkan metode absorbansi untuk melihat pertumbuhan mikroalga B. braunii.

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In some countries, the development of biotechnology has launched a food product known as health food. Now microalgae can be sold in capsule or in foods such as drinks and pasta that has shown efficacy in the treatment of treatment of conditions such as hypercholesterolemia and atherosclerosis. This study aims to determine levels of protein in microalgae Botryococcus braunii with variations in the visible light spectrum with Biuret method. Results for the protein content of the visible light spectrum variation is 17.60% for direct light, 13.48% for giving the red light and 11.82% for blue light giving. The highest amino acid B.braunii owned both the sample A, sample B and sample C is Leucine for amino acids essential and Alanine for non-essential amino acids. In this study, can also be obtained capacitance value method is more relevant than the absorbance method to see the growth of microalgae B. braunii."

"This new edition presents an overview of biomimetics and biologically inspired structured surfaces. It deals with various examples of biomimetics which include surfaces with roughness-induced superomniphobicity, self-cleaning, antifouling, and controlled adhesion. The focus in the book is on the lotus effect, salvinia effect, rose petal effect, oleophobic/philic surfaces, shark skin effect, and gecko adhesion. This new edition also contains new chapters on the butterfly wing effect, bio, and inorganic fouling and structure and properties of nacre and structural coloration."

"Coconut is a very important plant for the livelihood of people in tropical countries. It is also used as an icon of tropical region. Coconut fruit is very heavy and can cause injuries if the fruit falls down and hits somebody who happens to be underneath a coconut tree. In order to avoid the accident,  the coconut fruits have to be regularly cut off. Coconut tree originated from in vitro cultured endosperm is a triploid plant that produces seedless fruit (without endocarp). Coconut fruit without endocarp is not heavy. The objective of this study was to investigate plant regeneration of fresh and in vitro cultured coconut endosperms. The fresh and developed in vitro cultured coconut endosperms were observed using histological analysis. Solid endosperm of seven month-old postanthesis coconut from “Samoan Dwarf†cultivar was freshly picked up and cultured in vitro on modified Branton & Blake formula. Histological study of fresh coconut endosperm showed that the endosperm consisted of parenchyma cells, which were relatively uniform in shape and size, with some nuclei consisted of 1 – 5 nucleoli. Three month-old calli of in vitro grown coconut endosperm in semi solid media showed that its cells varied in shape and size, characterized by high nucleus to cytoplasm ratio, high starch, protein and lipid contents which underwent many divisions. Seven month-old calli of in vitro grown coconut endosperm in liquid media showed embryogenic cells which resembled proembryos. Fourteen month-old bud-like structure of coconut endosperm in semi solid media showed a meristematic layer, tunica-corpus structure, cortex-like region and tracheids of xylem. These results indicated that the bud-like structure was an early stage of shoot bud formation in coconut endosperm. This is the first report of early stage of shoot bud formation occurring on coconut endosperm cultured in vitro."

"Sintesis biodiesel dengan proses sirkulasi pada reaktor unggun diam dirancang dengan memanfaatkan enzim lipase. Lipase dari Candida rugosa diimobilisasi pada kalsium alginat dan digunakan sebagai biokatalis pada reaktor. Kesesuaiian substrat diuji dengan penggunaan pelarut, metode penambahan bertahap, dan tanpa pelarut. Kalsium alginat menghambat difusivitas substrat menuju inti aktif enzim sehingga menyebabkan laju sintesis yang lambat di awal proses. Sintesis menggunaan metode penambahan bertahap mampu menghasilkan yield paling tinggi diantara pengujian substrat lain, sebesar 88,70% dalam 24 jam. Laju alir optimal yang didapatkan adalah 0,4 dan 1 ml/menit, menghasilkan biodiesel dalam laju konversi yang lebih tinggi. Konsentrasi optimal enzim lipase yang terimobilisasi adalah 0,2%(w/v minyak). Sintesis pada kondisi optimal mencapai yield 70,2% dalam 12 jam. Pengujian stabilitas enzim amobil dilakukan dan mampu menghasilkan 65,6% biodiesel pada siklus ke-tiga, mempertahankan 93,4% aktivitas relatif enzim terimobilisasi. Model kinetika berbasis Ping Pong Bi Bi dikembangkan dengan mengkosiderasi konsentrasi alkohol. Model diaplikasikan untuk memprediksi konsentrasi reaktan dan produk selama sintesis biodiesel di reaktor kolom isian. Pemodelan di excel menunjukkan bahwa model yang dihasilakn dapat memprediksi konsentrasi komponen dalam reaksi transesterifikasi.

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A packed bed reactor with circulation process was designed to synthesize biodiesel utilizing lipase enzyme. Candida rugosa lipase was immobilized in calcium alginate and used as biocatalyst in reactor. Compatibility of substrate was tested using the usage of solvent hexane, stepwise addition, and without solvent. It was found that calcium alginate limit the diffusivity of substrate causing slow reaction rate at the start of process. Stepwise addition method was found to be the most optimum compared to others in this research, producing yield 88.7% in 24 hours. Optimal flowrate are 0.4 and 1 ml/min, producing biodiesel at higher rate. Optimal concentration of lipase immobilized in calcium alginate is 0.2% of substrate. Synthesis under optimal condition produces yield 70.2% in 12 hours. Stability test of immobilized enzyme retains 93.4% of relative activity, obtaining yield 65.6% in 12 hours. The kinetic model based on Ping Pong Bi Bi was developed by considering alcohol concentration. The model was applied to predict the concentration of reactants and products during biodiesel synthesis in the filling column reactor. Modeling in excel shows that the resulting model can predict the concentration of components in the transesterification reaction."

"Penelitian ini mencakup rangkaian oksidasi kolesterol berupa studi oksidasi kolesterol, oksidasi dengan menggunakan substrat hewani, oksidasi dengan enzim terimobilisasi material magnetit silikon dioksida (M-SiO2)/magnetit kitosan (M-Chit) dan oksidasi dengan protein rekombinan Rhodococcus erythropolis BL21(DE3) (RhoChoA). Enzim kolesterol oksidase yang diproduksi dengan metode submerged fermentation dari Streptomyces sp memiliki nilai aktivitas sebesar 5,12 U/mL dan aktivitas RhoChoA sebesar 17,9 U/mL. Studi kinetika dilakukan dengan menggunakan orde satu dengan reaksi irreversible. Optimasi produksi enzim dilakukan dengan memperhatikan faktor suhu dan jenis substrat. Untuk meningkatkan karakteristik enzim, imobilisasi dilakukan pada enzim kolesterol oksidase Streptomyces sp. Material magnetit disintesis dengan metode sol-gel dengan modifikasi menggunakan magnetit silikon dioksida dan magnetit kitosan yang diberi kode M-SiO2 dan M-Chit secara berurutan. Enzim hasil produksi diimobilisasi dengan menggunakan teknik cross-linking. Hasil karakterisasi FTIR dari material magnetit menunjukkan gugus fungsi M-O di bilangan gelombang 559,88; 598,91 dan 680,1 cm‑1 , gugus Si-O di bilangan gelombang 1615,78 dan 1761,65 cm-1.Uji oksidasi dilakukan dengan beberapa variabel bebas yaitu konsentrasi enzim (0,5; 1; 2 mg/mL), konsentrasi substrat (0,75; 1,25; 2,5 mg/mL), waktu oksidasi (5, 30, 60, 120, 180 menit), serta bentuk enzim (ekstrak kasar enzim kolesterol oksidase dan enzim kolesterol oksidase terimobilisasi). Hasil uji oksidasi dikuantifikasi dengan menggunakan HPLC untuk menganalisis konsentrasi substrat dan konsentrasi enzim yang optimum dalam oksidasi yang dijadikan sebagai referensi dalam penentuan uji biosensor kolesterol. Oksidasi kolesterol dengan menggunakan substrat hewani dilakukan dengan ekstraksi dengan pelarut lemak. Kuantifikasi kadar kolesterol dalam sampel menunjukkan susbtrat dari lemak hewani memiliki konsentrasi kolesterol tertinggi dari kuning telur dengan konsentrasi 1,94 mg/mL, hati ayam (0,93 mg/mL), daging sapi (0,25 mg/mL) dan daging ayam (0,23 mg/mL). Enzim kolesterol oksidase dengan konsentrasi 2 mg/mL dapat mengoksidasi ekstrak kasar kolesterol dari kuning telur, hati ayam dan daging ayam hingga teroksidasi 20%, sedangkan ekstrak kasar kolesterol dari daging sapi teroksidasi sebesar 10%. Hasil uji oksidasi dengan menggunakan HPLC diperoleh konsentrasi substrat secara optimal dioksidasi oleh enzim terimobilisasi M-SiO2 dengan konsentrasi 20 mg/mL serta konsentrasi kolesterol 1,94 mM sebesar 90%, sedangkan enzim kolesterol oksidase bebas mengoksidasi kolesterol sebesar 80%. Uji oksidasi kolesterol menggunakan enzim kolesterol oksidase terimobilisasi magnetit kitosan (M-Chit) ditemukan konsentrasi substrat yang optimum adalah 2,5 mg/mL dan konsentrasi enzim yang paling efektif adalah 2 mg/mL. Reaksi oksidasi kolesterol dengan kondisi optimum dan menggunakan enzim terimobilisasi M-Chit dapat mengoksidasi kolesterol sampai 10%. Uji penggunaan kembali material M-Chit dalam proses imobilisasi dapat digunakan sebanyak 2 kali.

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This research includes a series of cholesterol oxidation in the form of cholesterol oxidation studies, oxidation using animal substrates, oxidation with immobilized enzymes of magnetite silicon dioxide (M-SiO2) / magnetite chitosan (M-Chit) and oxidation with recombinant protein Rhodococcus erythropolis BL21 (DE3) ( RhoChoA). Cholesterol oxidase enzyme produced by the submerged fermentation method from Streptomyces sp has an activity value of 5.12 U / mL and a RhoChoA activity of 17.9 U / mL. The kinetic study was carried out using first order with an irreversible reaction. Optimization of enzyme production is carried out by controlling the temperatur and type of substrate. To improve the characteristics of the enzyme, immobilization was carried out on the cholesterol oxidase enzyme Streptomyces sp. The magnetite material was synthesized by the sol-gel method with modification using magnetite silicon dioxide and magnetite chitosan which were coded M-SiO2 and M-Chit, respectively. The immobilized enzymes are produced using a cross-linking technique. The FTIR characterization results of the magnetite material showed the M-O functional group at wave number 559.88; 598.91 and 680.1 cm-1, the Si-O group at wave numbers 1615.78 and 1761.65 cm-1.

The oxidation test was carried out with several independent variables, namely enzyme concentration (0.5; 1; 2 mg / mL), substrate concentration (0.75; 1.25; 2.5 mg / mL), oxidation time (5, 30, 60, 120, 180 minutes), as well as the form of the enzyme (crude extract of the cholesterol oxidase enzyme and the immobilized cholesterol oxidase enzyme). The results of the oxidation test were quantified using HPLC to analyze the optimum substrate concentration and enzyme concentration in oxidation which were used as references in determining the cholesterol biosensor test. Cholesterol oxidation using animal substrates was carried out by extraction with fat solvents. The quantification of cholesterol levels in the sample showed that the animal fat substrate had the highest cholesterol concentration from egg yolks with a concentration of 1.94 mg / mL, chicken liver (0.93 mg / mL), beef (0.25 mg / mL) and chicken meat. (0.23 mg / mL). Cholesterol oxidase enzyme with a concentration of 2 mg / mL can oxidize the crude extract of cholesterol from egg yolk, chicken liver and chicken meat up to 20%, while the crude extract of cholesterol from beef is oxidized only 10%. The results of the oxidation test using HPLC showed that the optimal substrate concentration was oxidized by the immobilized enzyme M-SiO2 with a concentration of 20 mg / mL and a cholesterol concentration of 1.94 mM of 90%, while the free cholesterol oxidase enzyme was 80% oxidized. Cholesterol oxidation test using immobilized cholesterol oxidase enzyme magnetite chitosan (M-Chit) found that the optimum substrate concentration was 2.5 mg / mL and the most effective enzyme concentration was 2 mg / mL. Cholesterol oxidation reaction under optimum conditions and using the immobilized enzyme M-Chit can oxidize cholesterol up to 10%. The M-Chit reuse test in the immobilization process can be used for 2 times."

"Chitosan can be prepared in the form of microspheres that serve as a depot for bioactive compounds released in a controlled way to diseased organs. In this study, a mathematical model of potassium chloride release from chitosan microspheres was developed. The model was validated using experimental data. The potassium chloride-loading percentages of 10.01%, 20.84%, and 20.57% were prepared using a cross-linking method. The potassium chloride loading was kept constant at about 20% when the potassium chloride mass in the preparation stage was above 5.024 mg/mL. Experiments and a model calculation of potassium chloride release from the microspheres with a loading of 10.01% and 20.57% were performed. In general, the model reproduces the experimental data. The experiments and the calculation show that during the same period, microspheres containing more potassium chloride release a higher percentage of potassium chloride than do microspheres containing less potassium chloride."