Judul: Hidrolisis Pati Palma Menggunakan α-Amilase
Abstrak: Today, carbohydratesmostly supplied fromcerealand tuber crops.Even thoughit many other sources of starch for industrial rawmaterials, one of them is palm trees. To explore it’s possibility, thusneedinformation on the physico-chemical properties and processing technology of the starch. The objective of this study were to examine the correlation between starch as substrate and types of enzymes, it’s also to know attack action pattern of the enzyme to glycosides linkages in the starch. Hydrolysis of starch used bacterial α-amylase, porcine pancreatin α-amylase, glucoamylase, dextrozymes, and monitored the changes on the value of DE (dextrose equivalent) and DP (degree of polymerization). The values giveinformation aboutthe types of hydrolysis products and starch digestibility by pancreatin amylasefrom some kind of palm starch. The result showed the palm starches are normal starch with 20.04-26.67% of amylose contents. All palm starches can be utilized as substrates for raw material for starch hydrolysates industry. Completed hydrolysis of palm starch enzymatically produced average 􀜦􀴤􀴤􀴤􀜲􀴤2.23-2.62 and􀴤􀜦􀴤􀴤􀜧􀴤38.27-44.9 for bacterial α-amylase, and average􀴤􀜦􀴤􀴤􀜲􀴤 2.28-3.31 and 􀴤􀜦􀴤􀴤􀜧􀴤30.27-43.91for pancreatin α-amylase.Onthe stage of saccharification, dextrozyme more effective than glucoamylasefor debranching of α-1,6-glycosides linkages so that result value of DEgreater than glucoamylase with the average 􀜦􀴤􀴤􀴤􀜧􀴤95.74-98.81 and􀴤􀜦􀴤􀴤􀜲􀴤 1.01-1.04 for dextrozyme, and average 􀜦􀴤􀴤􀴤􀜧􀴤94.65-98.21and􀴤􀜦􀴤􀴤􀜲􀴤 1.02-1.06 for amiloglukosidase.Palm starch from Arenga pinnatahas a digestibilityvaluehigherthanothertypes ofpalmstarch.
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Judul: Hidrolisis Pati Palma Menggunakan Pullulanase dan β-Amilase
Abstrak: Palm trees are unexplored carbohydrate sources that wiidely spread in Indonesia. Palm starches are still under utilized since lacked information about their pysico-chemical properties. Hydrolysis of these starches are the right application without concerning their characteristics. This research investigated the starches from five types of palm trees, namely Metroxylon sago (commersial sago), Metroxylon sp. (sagu rumbia), Arenga pinnata, Arenga microcarpa (sagu baruk), and Caryota mitis; and the hydrolysis of palm starches by using degrading enzymes, i.e. pullulanase and β- amylase. The result showed that palm starches are normal starch which contain17-21% of amylose or 83-79% of amylopectin which differed in branch-chain lengths, and caused typical products from each type of palm. Pullulanase as debranching enzymes, cleaveged the starch to produce DP 13.9- 20.8 of Short-Chains Amylose (SCA). The starch contained 22.2-38.8% of β-limit dextrins as the residue of β-amylolysis. Simultaneous hydrolysis by using β-amylase and pullulanase mainly produced maltose for all starch with DP of 1.7-2.9.
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Judul: A Continuous Vaccination Strategy in the SVIR Epidemic Model
Abstrak: Vaccination is conducted to minimize the spread of a disease. The vaccination is usually done several times within a fixed time interval. In the SVIR model, it is assumed that individuals do not get immediate immunity following a vaccination program. So according to process of vaccination on SVIR model, there are two strategies, i.e. the continuous vaccination strategy (CVS) and the pulse vaccination strategy (PVS). In this study, only the CVS strategy in epidemic model SVIR is considered. Results of the study indicate that dynamics of the CVS system depends on the basic reproductive number. If the basic reproductive number is less than one, then the disease-free fixed point is asymptotically stable. It means that the disease will eventually disappear from the population. Conversely, if the basic reproductive number is greater than one, then the endemic fixed point is asymptotically stable, which means that the disease will remain exist in the population. Simulation result shows that the vaccination would minimize the spread of disease by reducing the basic reproductive number. If the time for the vaccinated recipients to obtain the immunity, as well as a possibility of vaccinated recipients to be infected are neglected, then the disease will be eradicated. This condition is called an over-evaluating effect of vaccination.
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