Glucoamylase production by the marine yeast Aureobasidium pullulans N13d and hydrolysis of potato starch granules by the enzyme

2007 ◽  
Vol 42 (3) ◽  
pp. 462-465 ◽  
Author(s):  
Haifeng Li ◽  
Zhenming Chi ◽  
Xiaohui Duan ◽  
Lin Wang ◽  
Jun Sheng ◽  
...  
2006 ◽  
Vol 12 (1) ◽  
pp. 19-25
Author(s):  
Ruth Melliawati ◽  
Ricky Setiadi Suherman ◽  
Bambang Subardjo

Production of glucoamylase generally used through the fermentation-using microorganism. One of microorganism source which never been studied are from endophyte fungus. The purpose of this research is to study the potential microbes of Gunung Halimun Nasional Park (GHNP) for glucoamylase production. Thirty-seven isolate of endophyte fungi has been investigated for the ability of glucoamylase production on PSA (Potato starch agar) media with the strength of clear zone and colony. The potential isolates inoculated to Czapek media to produce glucoamylase on 50 ml scale and measured its activity every 24 hours of incubation time for 96 hours. The best isolate then was reproduced on the larger media (100 ml), and resumed with filtration and ultra-filtration. The enzyme activity, specific activity, and degree of protein was measured in every phase. Selection of amylolitic strength resulted that HL.110F.488 produced the highest amylolitic strength with halo size of 10.47 cm2, or equal with hydrolysis of starch of 0.0494 gram for 96 hours, while both isolate HL.44F.199 and HL.45F.205 had low amylolitic capacities but a very wide of colony growth, each 38.54 cm2 and 30.76 cm2. Isolat HL.44F.199 produced the highest enzyme activity of 5452.633 unit at 72 hours fermentation, while isolate HL.45F.205 with 4725.58 units at 72 hours fermentation and isolate HL.110F.488 with 3167.609 units at 96 hours fermentation. Glucoamylase has been reproduced by isolate HL.44F.199 on volume media 100 ml. The results show that enzyme activity is 4197.10 units with specific activity 2851.44 U/mg proteins, both get an increasing result after filtration and ultra-filtration reach out 5910.86 units and 4534.45 U/mg proteins.


Author(s):  
Jean-Claude Jésior ◽  
Roger Vuong ◽  
Henri Chanzy

Starch is arranged in a crystalline manner within its storage granules and should thus give sharp X-ray diagrams. Unfortunately most of the common starch granules have sizes between 1 and 100μm, making them too small for an X-ray study on individual grains. There is only one instance where an oriented X-ray diagram could be obtained on one sector of an individual giant starch granule. Despite their small size, starch granules are still too thick to be studied by electron diffraction with a transmission electron microscope. The only reported study on starch ultrastructure using electron diffraction on frozen hydrated material was made on small fragments. The present study has been realized on thin sectioned granules previously litnerized to improve the signal to noise ratio.Potato starch was hydrolyzed for 10 days in 2.2N HCl at 35°C, dialyzed against water until neutrality and embedded in Nanoplast. Sectioning was achieved with a commercially available low-angle “35°” diamond knife (Diatome) after a very carefull trimming and a pre-sectioning with a classical “45°” diamond knife. Sections obtained at a final sectioning angle of 42.2° (compared with the usual 55-60°) and at a nominal thickness of 900Å were collected on a Formvar-carbon coated grid. The exact location of the starch granules in their sections was recorded by optical microscopy on a Zeiss Universal polarizing microscope (Fig. 1a). After rehydration at a relative humidity of 95% for 24 hours they were mounted on a Philips cryoholder and quench frozen in liquid nitrogen before being inserted under frozen conditions in a Philips EM 400T electron microscope equipped with a Gatan anticontaminator and a Lhesa image intensifier.


Author(s):  
M. Alekseenko ◽  
V. Litvyak ◽  
A. Sysa ◽  
E. Hrabovska ◽  
O. Galenko

Mycologia ◽  
1984 ◽  
Vol 76 (4) ◽  
pp. 643 ◽  
Author(s):  
Federico Federici

RSC Advances ◽  
2017 ◽  
Vol 7 (76) ◽  
pp. 48444-48453 ◽  
Author(s):  
Benjarat Bunterngsook ◽  
Thanaporn Laothanachareon ◽  
Suda Natrchalayuth ◽  
Sirithorn Lertphanich ◽  
Tatsuya Fujii ◽  
...  

Cassava pulp is an underused agricultural by-product comprising residual starch granules entrapped in cell wall polysaccharides, making it unique from other lignocellulosic wastes in terms of enzymatic processing.


2021 ◽  
Author(s):  
amandine pruvost ◽  
stanislas helle ◽  
nicolas szydlowski ◽  
Christian ROLANDO

In the present work, we developed a miniaturized method for determining amylopectin chain length distribution (CLD) by fluorescence-assisted capillary electrophoresis (FACE). The method relies on single granule entrapping into capillaries followed by direct starch gelatinization and amylopectin debranching on carbograph-based solid phase extraction (SPE) cartridges. Sample desalting on HypersepTM tips following APTS-labelling and the use of nanovials allowed for the fluorescence analysis of weakly diluted samples. Consequently, method sensitivity was improved by 500-fold which is compatible with the analysis of single potato starch granules. The method was implemented to determine CLD profiles of single starch granules ranging from 50 to 100 µm in diameter. In these experiments, the relative proportion of starch glucans of up to 30 degrees of polymerization (DP) could be quantified.


2008 ◽  
Vol 55 (2) ◽  
pp. 89-93 ◽  
Author(s):  
Kaoru Kinoshita ◽  
Azusa Ito ◽  
Makoto Hattori ◽  
Tadashi Yoshida ◽  
Koji Takahashi

Sign in / Sign up

Export Citation Format

Share Document