scholarly journals Inhibitory Effects of Cyanide on the Activity of Granular Starch Hydrolyzing Enzyme (GSHE) during Hydrolysis of Cassava (Manihot Esculenta Crantz) Starch

2018 ◽  
Vol 63 (1) ◽  
pp. 11-17
Author(s):  
Hargono Hargono ◽  
Andri Cahyo Kumoro ◽  
Bakti Jos
Keyword(s):  
Manihot Esculenta ◽  
Maximum Velocity ◽  
Cassava Starch ◽  
Inhibitory Effects ◽  
Manihot Esculenta Crantz ◽  
Km Value ◽  
Hydrolysis Of ◽  
Reducing Sugar Concentration ◽  
Granular Starch ◽  
Burk Plot

The kinetics and inhibitory effects of cyanide on the granular starch hydrolyzing enzyme (GSHE) activity during hydrolysis of cassava (Manihot esculenta Crantz) starch at low temperature were studied. The substrates included native cassava starch at various concentrations (100-400 g/L) and native cassava starches with added cyanide at various concentrations (50-150 mg/kg), while the concentration of enzyme was 1.5% (w/w). A decrease in reducing sugar concentration during hydrolysis of cassava starch indicated that the cyanide reduced the enzyme activity. Lineweaver-Burk plot of Michaelis-Menten equation was used to study the inhibition kinetics. The maximum velocity (Vmax) value was higher for native cassava starch than that of native cassava starch with added cyanides. The presence of cyanide was found to reduce the Vmax values. No significant different of the saturation constant (Km) value between native cassava starch and native cassava starch with added cyanides was observed. Based on the inhibition type analysis, the effect of cyanide in the cassava starch can be classified as a noncompetitive inhibition, with the Ki value of 0.33 mg/L.

scholarly journals HIDROLISIS ASAM KLORIDA TEPUNG PATI SINGKONG (Manihot esculenta Crantz) DALAM PEMBUATAN GULA CAIR

2017 ◽  
Vol 5 (1) ◽  
pp. 83
Author(s):  
RTM. Sutamihardja ◽  
Srikandi Srikandi ◽  
Dian Purnamasari Herdiani
Keyword(s):  
Acid Hydrolysis ◽  
Manihot Esculenta ◽  
Sugar Content ◽  
Cassava Starch ◽  
Agricultural Products ◽  
High Potency ◽  
Hydrolysis Time ◽  
Manihot Esculenta Crantz ◽  
Hcl Concentration ◽  
Hydrolysis Of

Chloride Acid Hydrolysis of Cassava (Manihot esculenta Crantz) Strach Flour in Producing a Liquid Sugar         Cassava (Manihot esculenta Crantz), known as cassava or manioc is a tuber or root of a tree that long with a diameter average of 5-10 cm and a length of 50-80 cm, depending on the type of cassava. Cassava is agricultural products that having high potency source of carbohydrates for food and industrial materials. Cassava starch can be made for liquid sugar by the method of acid hydrolysis using hydrochloric acid. The research results showed that  rendemen at a HCl concentration of 0.75 N and hydrolysis time of 90 minutes was 80.51%. The higest rendemen of liquid sugar at a concentration of 0.5 N HCl and the hydrolysis time of 90 minutes was 84.22%. Results of the analysis indicate liquid sugar content of 16.22% moisture, ash content of 1.46%, 2.16% protein content, fat content of 0.53%, carbohydrates of 63.90%, and a negative starch content.Key words: Cassava,  Flour Cassava Starch, Acid  Hydrolysis, Liquid Sugar ABSTRAK         Singkong (Manihot esculenta Crantz) yang dikenal sebagai ketela pohon atau ubi kayu merupakan umbi atau akar pohon yang rata-rata berdiameter 5-10 cm dan panjang 50-80 cm, tergantung dari jenis singkong. Singkong merupakan hasil produk pertanian yang potensinya tinggi sebagai sumber karbohidrat untuk bahan pangan dan industri. Pati singkong dapat dibuat gula cair dengan metode hidrolisis asam menggunakan asam klorida. Hasil penelitian menunjukkan bahwa nilai rendemen tertinggi pada konsentrasi HCl 0,75 N dan waktu hidrolisis 90 menit yaitu sebesar 80,51%.  Rendemen tertinggi kadar gula pereduksi dari pembuatan gula cair dengan konsentrasi HCl 0,5 N dan waktu hidrolisis 90 menit sebesar 84,22%. Hasil analisa gula cair menunjukkan kandungan kadar air 16,22%, kadar abu 1,46%, kadar protein 2,16%, kadar lemak 0,53% , karbohidrat 63,90%, dan kandungan pati negatif.Kata kunci: Singkong, Tepung Pati Singkong, Hidrolisis Asam, Gula Cair

scholarly journals Production of glucose and fructose syrups from cassava (Manihot esculenta Crantz) starch using enzymes produced by microorganisms isolated from Brazilian Cerrado soil

2010 ◽  
Vol 30 (1) ◽  
pp. 213-217 ◽  
Author(s):  
Roberto do Nascimento Silva ◽  
Fábio Pereira Quintino ◽  
Valdirene Neves Monteiro ◽  
Eduardo Ramirez Asquieri
Keyword(s):  
Aspergillus Niger ◽  
Manihot Esculenta ◽  
Glucose Isomerase ◽  
Cassava Starch ◽  
Maximum Activity ◽  
Brazilian Cerrado ◽  
Initial Activity ◽  
Manihot Esculenta Crantz ◽  
Streptomyces Sp ◽  
Optimum Ph

The high demands for sugars and the development of enzymatic technology have increased the production of sweeteners, especially for glucose and fructose syrups. This work describe a technology for glucose and fructose syrups from Brazilian cassava starch using enzymes produced by soil microrganisms isolated from the Brazilian Cerrado soil. Firstly, Aspergillus niger and Streptomyces sp. were isolated from the soil and used as glucoamylase (GA) and glucose isomerase (GI) producer sources. After characterization, GA and GI exhibited optimum pH 4.5 and 8.0, respectively. GA showed maximum activity at 60 ºC and GI at 85 ºC. GA and GI retained 65 and 80%, respectively, of initial activity after 180 minutes of incubation at 60 ºC. The kinetic parameters Km and Vmáx were 0.476 (mg.mL-1) and 8.58 (µmol/minute) for GA and 0.082 (M) and 48.20 (µmol/minute) for GI. The maximum glucose syrups production occurred after 24 hours of reaction with a 98% yield. The production of fructose syrups with 42% (w/v) was reached after 96 hours of reaction.

Inhibitory effect of soil humic compounds on the proteolytic enzyme pronase

Soil Research ◽  
1969 ◽  
Vol 7 (3) ◽  
pp. 241
Author(s):  
JN Ladd ◽  
JHA Butler
Keyword(s):  
Humic Acids ◽  
Maximum Velocity ◽  
Kinetic Studies ◽  
Inhibitory Effect ◽  
Enzymic Activity ◽  
Humic Compounds ◽  
Km Value ◽  
Group Basis ◽  
Inhibitory Power ◽  
Hydrolysis Of

Neutralized solutions of soil humic acids inhibit the proteolytic activity of the enzyme pronase when tested against a variety of substrates. Protein hydrolysis was less sensitive than hydrolysis of dipeptide derivatives; 50% inhibition of benzyloxycarbonylglycylleucine hydrolysis was achieved with concentrations of humic acids as low as 1-2 �g/ml or less than 10-5M, on a carboxyl group basis. Humic acids, extracted from soils with different crop histories, showed only slight differences in their effectiveness as inhibitors of pronase activity. Their inhibitory power was comparable with that of other high molecular weight polyanions, e.g. polyacrylic acid and polycondensates derived from p-benzoquinone and catechol. Alginic acid was a relatively poor inhibitor. Preincubation of humic acids for various periods with either pronase or substrate (albumin or benzyloxycarbonylglycylleucine) had little or no effect on the subsequent inhibition of enzymic activity. However, inhibition is decreased by increasing substrate concentrations, following preincubation of humic acids and pronase. Both observations are consistent with a reversible inhibitory mechanism. Kinetic studies demonstrate that humic acids inhibit pronase activity towards albumin and N-benzyloxycarbonyl dipeptides by effectively reducing the affinity of pronase for the substrate, i.e. by increasing the Km value for the reaction. With benzoylarginine amide and benzoylarginine ethyl ester as substrates, the reaction velocity is lowered due to a reduction of the maximum velocity of the system. Both effects may possibly be explained by a conformational change in the enzyme structure due to combination with the humic acid molecules.

Effects of high energy milling on some functional properties of jicama starch (Pachyrrhizus erosus L. Urban) and cassava starch (Manihot esculenta Crantz)

2007 ◽  
Vol 78 (4) ◽  
pp. 1212-1220 ◽  
Author(s):  
F. Martínez-Bustos ◽  
M. López-Soto ◽  
E. San Martín-Martínez ◽  
J.J. Zazueta-Morales ◽  
J.J. Velez-Medina
Keyword(s):  
Functional Properties ◽  
Manihot Esculenta ◽  
High Energy ◽  
Cassava Starch ◽  
Manihot Esculenta Crantz ◽  
High Energy Milling

scholarly journals Waktu Optimum Hidrolisis Pati Limbah Hasil Olahan Ubi Kayu (Manihot esculenta Crantz var. Lahumbu) Menjadi Gula Cair Menggunakan Enzim α-Amilase Dan Glukoamilase

2018 ◽  
Vol 5 (2) ◽  
pp. 86-95
Author(s):  
Ardiansyah Ardiansyah ◽  
Nurlansi Nurlansi ◽  
Rustam Musta
Keyword(s):  
Manihot Esculenta ◽  
Reducing Sugar ◽  
Sugar Concentration ◽  
Optimum Time ◽  
Manihot Esculenta Crantz ◽  
A Value ◽  
Time Required ◽  
Reducing Sugar Concentration

This study aims to determine optimum time of action of the enzyme α-amylase and glucoamylase needed in hydrolyze of starch from waste processed cassava (Manihot esculenta Crantz var. Lahumbu). This research was conducted through three main stages, namely the gelatinization, liquefaction and saccharification. The method was used method are liquefaction and  saccharification. The variation time of the stage liquefaction: 12; 24; 36; 48; 60; and 72 minutes and the saccharification stage are: 9; 18; 27; 36; 45; 54; and 63 hours. The results showed that the optimum time required for stage liquefaction using α-amylase enzyme is 48 minutes on the condition of a temperature of 80 oC with a value of 0.09% amylose levels were measured using UV-Vis spectrophotometer. The optimum time required for saccharification step using a glucoamylase which is 54 hours on the conditions of a temperature of 50oC with the amount of reducing sugar concentration of 9.186 g/L as measured using a UV-Vis spectrophotometer.

Production and characterization of oxidized cassava starch (Manihot esculenta Crantz) biodegradable films

2011 ◽  
Vol 63 (10) ◽  
pp. 595-603 ◽  
Author(s):  
Renata Baraldi de Pauli ◽  
Leda Battestin Quast ◽  
Ivo Mottin Demiate ◽  
Lyssa Setsuko Sakanaka
Keyword(s):  
Manihot Esculenta ◽  
Cassava Starch ◽  
Biodegradable Films ◽  
Manihot Esculenta Crantz

The phenolic constituents from leaves of Manihot esculenta

1974 ◽  
Vol 52 (11) ◽  
pp. 2381-2386 ◽  
Author(s):  
M. L. Thakur ◽  
B. H. Somaroo ◽  
W. F. Grant
Keyword(s):  
Manihot Esculenta ◽  
Uv Light ◽  
Manihot Esculenta Crantz ◽  
Benzoic Acid Derivatives ◽  
Phenolic Constituents ◽  
Ferulic Acids ◽  
Color Reactions ◽  
Hydrolysis Of ◽  
Spray Reagents ◽  
Acid Esters

A total of 55 phenolic constituents was extracted with methanol – 1 % HCl at room temperature from dried leaves of cassava (Manihot esculenta Crantz). By means of thin-layer chromatographic and spectrophotometric techniques the 20 main phenolic constituents were identified as quercetin and luteolin glycosides, chlorogenic acid, esters of p-coumaric, caffeic, ferulic, and sinapic acids, and the glycosides of caffeic and ferulic acids. Benzoic acid derivatives were also confirmed. Acid and alkaline hydrolysis of the major compounds was carried out to determine their aglycones. Ultraviolet (UV) spectral data, Rf values, fluorescence in UV light, and color reactions with chromogenic spray reagents of the phenolic compounds and the aglycones are presented. The sugar residues of the major flavonoid compounds were identified as glucose.

scholarly journals Potential of cassava starch from TME 419 as suitable gelling agent in micropropagation of cassava (Manihot esculenta Crantz)

2017 ◽  
Vol 11 (12) ◽  
pp. 403-407
Author(s):  
K. NKERE Chukwuemeka ◽  
IKPEAMA Ahamefula ◽  
O. UZOECHI Amarachukwu ◽  
N. A. MBANASO Egbichi
Keyword(s):  
Manihot Esculenta ◽  
Cassava Starch ◽  
Gelling Agent ◽  
Manihot Esculenta Crantz
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