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"Biopolymers : applications and trends provides an up-to-date summary of the varying market applications of biopolymers characterized by biodegradability and sustainability. It includes tables with the commercial names and properties of each biopolymer family, along with biopolymers for each marketing segment, not only presenting all the major market players, but also highlighting trends and new developments in products.The book includes a thorough breakdown of the vast range of application areas, including medical and pharmaceutical, packaging, construction, automotive, and many more, giving engineers critical materials information in an area which has traditionally been more limited than conventional polymers.In addition, the book uses recent patent information to convey the latest applications and techniques in the area, thus further illustrating the rapid pace of development and need for intellectual property for companies working on new and innovative products."

"Biopolymers reuse, recycling and disposal is the first book covering all aspects of biopolymer waste management and post-usage scenarios, embracing existing technologies, applications, and the behavior of biopolymers in various waste streams.The book investigates the benefits and weaknesses, social, economic and environmental impacts, and regulatory aspects of each technology. It covers different types of recycling and degradation, as well as life cycle analysis, all supported by case studies, literature references, and detailed information about global patents. Patents in particular—comprising 80% of published technical literature in this emerging field, widely scattered, and often available in Japanese only—are a key source of information.Dr. Niaounakis draws on disciplines such as polymer science, management, biology and microbiology, organic chemistry, environmental chemistry, and patent law to produce a reference guide for engineers, scientists and other professionals involved in the development and production of biopolymers, waste management, and recycling. This information is also valuable for regulators, patent attorneys and academics working in this field."

"This book describes in detail the background to and objective of the development, materials, manufacturing processes, functions and future prospects of a number of ceramic products. Not merely about the science and technology of ceramic manufacturing, the book is about the products themselves, as it tries to clarify how ceramics continue to contribute to our lives. It is the first such work to show advanced ceramic products in detail, from the technologies used to their application, and can be seen as a kind of illustrated reference book for modern advanced ceramic products as it is filled with easy-to-understand illustrations and photos. "

"Lipase B Candida antarctica (CALB) secara ekstensif dipelajari dalam produksi biodiesel, produk farmasi, deterjen, dan senyawa lainnya secara enzimatis. Salah satu kekurangan penggunaan CALB adalah suhu optimumnya yang relatif rendah pada 40oC (313 K). Tujuan penelitian ini adalah untuk merancang mutan CALB yang lebih termostabil dibanding CALB wild type dengan rekayasa penambahan ikatan disulfida. Simulasi dinamika molekul dilakukan untuk mengamati proses unfolding atau denaturasi termal CALB. Denaturasi termal CALB dipercepat dengan melakukan simulasi pada suhu tinggi. Simulasi dinamika molekul CALB dilakukan dengan perangkat lunak GROMACS pada suhu 300-700 K. Prediksi pasangan residu yang dapat dimutasi menjadi sistein dilakukan dengan perangkat lunak ?Disulfide by DesignTM?. Pemilihan residu yang dimutasi, didasarkan pada hasil analisis fleksibilitas CALB. Berdasarkan hasil analisis tersebut dirancang tiga mutan enzim CALB yaitu Mutan-1 (Leu73Cys/Ala151Cys), Mutan-2 (Trp155Cys/Glu294Cys), dan Mutan- 3 (Thr43Cys/Ser67Cys). Parameter yang digunakan untuk membandingkan termostabilitas enzim mutan dengan wild type adalah RMSD, SASA (solvent accessible surface area), jari-jari girasi (Rg), dan struktur sekunder. Simulasi dinamika molekul yang dilakukan pada ketiga mutan tersebut menunjukkan bahwa Mutan-1 memiliki termostabilitas yang lebih baik dibanding CALB wild type. Diharapkan hasil penelitian ini dapat memberikan saran rancangan mutasi yang dapat diimplementasikan ke dalam laboratorium basah (wet experiment).

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Candida antarctica lipase B (CALB) is extensively studied in enzymatic production of biodiesel, pharmaceutical products, detergents, and other chemicals. One drawback of using CALB is its relatively low optimum temperature at 313 K (40oC). The objective of this research is to design CALB mutant with improved thermostability by introducing extra disulfide bond. Molecular dynamic simulation was conducted to get better insight on the process of thermal denaturation or unfolding in CALB. Thermal denaturation of CALB was accelerated by conducting simulation at high temperature. Molecular dynamic simulation of CALB was performed with GROMACS software package at 300-700 K. Prediction of possible mutation was conducted using ?Disulfide by DesignTM? software. Selection of mutated residues was based on flexibility analysis of CALB.

From those analyses, three mutants were designed, which are Mutant-1 (73LeuCys/151AlaCys), Mutant-2 (155TrpCys/294GluCys), and Mutant-3 (43ThrCys/67SerCys). Parameters that were used to compare the thermostability of mutant with wild type enzyme were RMSD, SASA (solvent accessible surface area), radius of gyration (Rg), and secondary structure. Molecular dynamic simulation conducted on those three mutants showed that Mutant-1 have better thermostability compared to wild type CALB. The resulted mutant design will be used as a suggestion to engineer CALB mutant in wet experiment."

"Polianilin (PANI) (emeraldin terprotonasi / ES) berukuran kecil disintesis secara Bulk Polymerization dengan mengoksidasi anilin menggunakan Amonium Peroksodisulfat (APS) dengan dopan HCl. Hubungan antara pengaruh kondisi polimerisasi seperti: konsentrasi HCl, rasio mmol APS/Anilin, konsentrasi reagen, dan temperatur polimerisasi dengan distribusi ukuran partikel dipelajari menggunakan PSA (Particle Size Analyzer). Pengaruh ukuran partikel terhadap waktu kontak pembentukan PANI terdeprotonasi (emeraldin basa / EB) dipelajari dengan menggunakan ES berukuran terkecil. Sulfonasi pada EB dilakukan dengan menggunakan jumlah H2SO4 pekat (95-97%) yang berbeda menghasilkan emeraldin basa tersulfonasi, EBS 1 dan EBS 2, dimana EBS 2 diperoleh menggunakan H2SO4 pekat kurang lebih dua kali lebih banyak daripada EBS 1. Selanjutnya EB, EBS 1, dan EBS 2 digunakan untuk mereduksi Cr(VI). Karakterisasi produk dilakukan dengan menggunakan PSA, SEM, spektrofotometer UV-Vis, dan FT-IR. Ukuran partikel terkecil ES 0,452μm (24,4% Vol.) didapatkan dari rasio mmol APS/Anilin 0,07 dengan konsentrasi APS/Anilin 3,12x10-2 M/87,2x10-2 M dalam HCl 3 M. Pengamatan menggunakan SEM terhadap partikel tersebut menghasilkan morfologi nanofiber (diameter ±100nm). Dedoping Nanofiber ES dalam NaOH 0,1M berlangsung dalam waktu kontak optimum selama 3 Jam. EB, EBS 1, dan EBS 2 mampu mereduksi Cr(VI) dalam larutan. Kecepatan dan kapasitas reduksi Cr(VI) diperoleh dengan urutan EBS2 > EBS1 > EB.

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Polianilin (PANI) (emeraldine salt / ES) with small particle size was synthesized by Bulk Polymerization from aniline with ammonium peroxodisulfate (APS) as oxidator and HCl as a dopan. The relationship between polymerization conditions such as: concentration of HCl, the mmole ratio of APS/aniline, reagent concentration, and temperature of polymerization with the distribution of particle sizes studied using PSA (Particle Size Analyzer). The contact time of deprotonated PANI (emeraldine base / EB) formation from ES with smallest particle size was studied. Furthermore, sulfonation on EB was carried out using different amount of concentrated H2SO4 (95-97%) to produced sulfonated emeraldin, EBS 1 and EBS 2. EBS 2 was preparered by using twice amount of concentrated H2SO4 than for EBS 1. Finally, the EB, EBS 1 and EBS 2 prepared were used for reducing Cr(VI). Characterizations of products were observed by using PSA, SEM, UV-Vis spectrophotometer, and FT-IR. ES with smallest particle size 0.452 μm (24.4% Vol.) was obtained from the mmole ratio of APS/aniline 0.07 with the APS/aniline concentration 3.12 x10-2 M/87.2x10-2 M in HCl 3 M. The morphology of the particles shown nanofiber (diameter ± 100nm). Dedoping nanofiber ES in 0.1 M NaOH took place within 3 hours. EB, EBS 1 and EBS 2 prepared can be used to reduce Cr (VI) in solution. The reduction rate and capacity for Cr(VI) is in order of EBS 2 > EBS 1 > EB."

"Microbial Elctrolysis Cell adalah suatu sistem biokimia yang memproduksi gas Hidrogen dari bahan organik yang terkandung dalam air limbah. Produksi hidrogen dapat berkurang karena proton CO2 dan hidrogen membentuk metana dan air yang disebabkan oleh bakteri metanogenik. Katalis AC-Fe/SS dipilih karena karbon aktif memiliki luas permukaan yang tinggi serta aktivitas dan stabilitas Fe yang baik. Metode adsorpsi dan fase inversi digunakan untuk menggabungkan AC-Fe pada SS. Penelitian dilakukan dalam reaktor 100mL MEC selama 258 jam. Hidrogen dianalisis dengan GC-TCD. Pengukuran tegangan dilakukan dengan multimeter dan pertumbuhan bakteri dianalisis dengan spektrofotometer. Fraksi gas hidrogen terbesar adalah 60% dengan AC-Fe/SS dan 0,08% tanpa menggunakan katalis. Nilai densitas optik untuk pertumbuhan mikroorganisme tertinggi adalah 0,611 dengan katalis AC-Fe/SS dan 0,427 tanpa menggunakan katalis. Densitas arus tertinggi adalah 99,11 mA / m2 dengan katalis AC-Fe/SS dan 59,52 mA / m2 tanpa menggunakan katalis. Pemodelan Dudley dilakukan menggunakan Matlab dan menunjukkan bahwa Umaxe adalah 1 /hari dan Qmaxe adalah 4,6 mg-S / mg-Xe / hari memiliki efek pada total mikroorganisme yang mendekati percobaan.

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Microbial Elctrolysis Cell is a biochemical system for producing Hydrogen gas from organic substances contained in wastewater. Hydrogen production can be reduced because CO2 and hydrogen protons form methane and water caused by methanogenic bacteria. The AC-Fe / SS catalyst was chosen because activated carbon had a high surface area and Fe had good activity and stability. The adsorption and phase inversion method were used to combine AC-Fe on SS. The research was carried out in a 100mL MEC reactor for 258 hours. Hydrogen was analyzed by GC-TCD. Voltage measurements was carried out with a multimeter and bacterial growth was analyzed with a spectrophotometer. The largest hydrogen gas fraction was 60% with AC-Fe / SS and 0.08% without using a catalyst. The highest optical density value for microorganism growth was 0.611 with AC-Fe / SS catalyst and 0.427 without using a catalyst. The highest current density was 99.11 mA / m2 with an AC-Fe / SS catalyst and 59.52 mA / m2 without using a catalyst. The Dudley modeling was done using Matlab and showed that Umaxe was 1 day-1 and Qmaxe was 4.6 mg-S / mg-Xe / day had an effect on the total microorganisms approaching the experiment."

"Proses korosi adalah peristiwa berkurangnya mutu material akibat reaksi kimia/elektro kimia dengan lingkungan yang terjadi secara alamiah. Khusus bidang industri otomotif, proses korosi merupakan hal yang paling sering menjadi masalah utama. Oleh karena itu perlu dilakukan perlindungan/proteksi untuk menjaga mutu material."

"Proyeksi penurunan suplai air bersih perkapita terjadi akibat keterbatasan sumber dan kenaikan populasi manusia. Pemanfaatan air laut yang berlimpah dengan teknologi desalinasi yang ada saat ini masih membutuhkan energi yang besar. Penelitian ini akan memaparkan hasil pengujian teknologi desalinasi baru yang hemat energi. Microbial Fuel Cell (MFC), yang bekerja dengan reaksi redoks dan merubah kesetimbangan ion, direkayasa dalam penelitian ini untuk desalinasi. MFC direkayasa menjadi 3 chamber (anoda-garam-katoda) yang dibatasi AEM (Anion Exchange Membrane) dan CEM (Cation Exchange Membrane), yang dinamakan MDC (Microbial Desalination Cell). Variasi jumlah elektroda, rasio kultur dan substrat di chamber anoda serta pengujian kenaikan volume kultur dan substrat di chamber anoda diamati pengaruhnya terhadap performa desalinasi dan jumlah energi listrik yang dihasilkan. Hasil penelitian ini menunjukkan bahwa dengan menggunakan 3 pasang elektroda, rasio kultur dan substrat 2:3 dan penaikan volume kultur dan substrat 1,5 kali menghasilkan performa desalinasi terbaik dengan laju desalinasi 0,377 mmol/jam, salt removal 34,52%, dan power density rata-rata 2,26.10-2 W/m3.

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Declining projection of clean water supply percapita is caused by restrictiveness of water sources and rise of human population. Sea water utilization using current desalination technology still require huge amount of energy.

This research provides new energy-saving desalination technology. Microbial fuel cell which work by redox reaction resulted in imbalance ion concentration among chambers is engineered for desalination application without external energy using 3 chambers (anoda-salt-cathode), named MDC (Microbial Desalination Cell). Number of electrodes, ratio of culture:substrate, volume progression of culture and substrate are evaluated in terms of desalination and electrical energy generating performance.

This research show that MDC using 3 pairs of electrodes, culture and substrate's ratio of 2:3, and culture and progression 1.5 times of culture and substrate’s volume, give best desalination performance by desalination rate 0.377 mmol/h, salt removal 34.52%, and average power density 2.26.10-2 W/m3."

"Tanin merupakan kelompok metabolit sekunder bagian dari senyawa polifenol yang cukup banyak ditemukan di dalam daun jambu biji (Psidium guajava). Tanin diketahui berpotensi sebagai inhibitor xantin oksidase, enzim yang berperan dalam hiperurisemia. Peningkatan produksi enzim ini akan berdampak pada penyakit pirai atau encok. Penelitian ini bertujuan untuk mengetahui yield ekstrak kasar daun jambu biji yang di ekstrak dengan metode sonikasi dengan pelarut yang berbeda, yaitu aseton 70%, etanol 70%, dan akuades, serta menguji inhibisi ekstrak terhadap aktivitas enzim xantin oksidase secara in vitro dan mengetahui kandungan senyawa tanin pada sampel yang memiliki persentase inhibisi tertinggi. Dari ketiga jenis pelarut tersebut, diketahui ekstrak akuades memiliki persentase inhibisi tertinggi yaitu sebesar 58,2% diikuti oleh ekstrak etanol 70% dan aseton 70% dengan persentase inhibisi masing-masing 38,6% dan 28,5%. Kandungan tanin dalam ekstrak akuades daun jambu biji cukup besar, yaitu sebesar 32,42 mg/g atau 3,242% (b/b). Hasil yang diperoleh menjelaskan dan mendukung penggunaan ekstrak dari daun jambu biji (Psidium guajava) untuk mencegah dan mengobati hiperurisemia.

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Tannin is secondary metabolite and one of polyphenolic substances that can be found in Psidium guajava leaves. Tannin is known for its potential as xanthine oxidase inhibitor, a key enzyme playing role in hyperuricemia. Overproduction of xanthine oxidase can cause gout.

This study aimed to obtain yield of crude extract from Psidium guajava leaves by using three different solvents, acetone 70%, ethanol 70%, and water. The crude extracts were used for in vitro xanthine oxidase inhibitory activity assay. Tannin content in the sample showing the highest degree of inhibition was also determined.

Aqueous extract exhibited the highest activity with an inhibition of 58.2%, followed by ethanol 70% and acetone 70% with an inhibition of 38.6% and 28.5% respectively. Tannin content in aqueous extract of Psidium guajava leaves is 32.42 mg/g or 3.242% (m/m) of total weight.

These results may explain and support the dietary use of the extracts of Psidium guajava leaves for the prevention and treatment of hyperuricemia."