Cassava Pulp as a Biofuel Feedstock of an Enzymatic Hydrolysis Process

Cassava pulp, a low cost solid byproduct of cassava starch industry, has been proposed as a high potential ethanolic fermentation substrate due to its high residual starch level, low ash content and small particle size of the lignocellulosic fibers. As the economic feasibility depends on complete degradation of the polysaccharides to fermentable glucose, the comparative hydrolytic potential of cassava pulp by six commercial enzymes were studied. Raw cassava pulp (12% w/v, particle size <320 μm) hydrolyzed by both commercial pectinolytic (1) and amylolytic (2) enzymes cocktail,yielded 70.06% DE. Hydrothermal treatment of cassava pulp enhanced its susceptibility to enzymatic cleavageas compared to non-hydrothermal treatment raw cassava pulp. Hydrothermal pretreatment has shown that a glucoamylase (3) was the most effective enzyme for hydrolysis process of cassava pulp at temperature 65 °C or 95 °C for 10 min and yielded approximately 86.22% and 90.18% DE, respectively. Enzymatic pretreatment increased cassava pulp vulnerability to cellulase attacks. The optimum conditions for enzymatic pretreatment of 30% (w/v) cassava pulp by apotent cellulolytic/ hemicellulolytic enzyme (4) was achieves at 50 °C for 3, meanwhile for liquefaction and saccharification by a thermo-stable α-amylase (5) was achieved at 95 °C for 1 and a glucoamylase (3) at 50 °C for 24 hours, respectively, yielded a reducing sugar level up to 94,1% DE. The high yield of glucose indicates the potential use of enzymatic-hydrothermally treated cassava pulp as a cheap substrate for ethanol production

Transformasi Plasmid Ptrli Dengan Teknik Elektroporasi Pada Aspergillus Terreus Dan Uji Stabilitas Transforman

Aspergillus terreus is a Saprophyte fungus that produces several secondary metabolites as lovastatin (anti-cholesterol drug) and itaconic acid (a polymer material). Lovastatin is one of the statin class of drugs that have efficacy as antihypercholesterolemic. Plasmid transformation is the introduction and incorporation of exogenous plasmid into cells orprotoplast. In this study, pTRLI plasmid (pTRI inserts containing lovE gene as a regulator gene in the biosynthesis of lovastatin) will be transformed by electroporation transformation. The purpose of this research is transformation of pTRLI plasmid into protoplasts of Aspergillus terreus by electroporation and obtain stable transformants. The research was initiated by isolation of pTRLI plasmid. Then pTRLI plasmid was determined purity and concentration by nanodrop. Furthermore, Protoplasts of Aspergillus terreus were isolated enzymatically by adding an enzyme which can degrade the cell wall of Aspergillus terreus which contains chitin and cellulose. PTRLI plasmid were transformed into protoplasts of Aspergillus terreus by electroporation. These transformants were grown in Czapek-Dox medium containing pyrithiamine agar and the number of transformants mg-1 of pTRLI plasmid was calculated. Transformants were selected to grow in Czapek-Dox medium containing piritiamin 1 mg l-1. The number of transformants produced 187 transformants mg-1 of PTRLI plasmid. Transformants are stable up to five generations by growing the transformants in Czapek-Dox medium agar containing piritiamin 1 mg l-1. The success of the transformation indicated by ptrA gene in transformants that can be amplified by PCR. The size of fragment DNA is 801 bp

Fisiologi tumbuhan : sel air, larutan dan permukaan

Jilid 1241 p. : il.; 29 cm

Fiisiologi tumbuhan : Perkembangnan tumbuhan dan fisiologi lingkungan

Jil. 316a, 343 p., : il.,; 29 cm

Fisiologi tumbuhan

16a,343 hlm.;30 c

Fisiologi tumbuhan

15a,241 hlm.;30 c

Fisiologi tumbuhan: perkembangan tumbuhan dan fisiologi lingkungan

16a, 343 hlm. : ilus. ; 29 cm