Improved Method for Detection of Starch Hydrolysis

Dhawale, Motiram R.; Wilson, J. Jeffrey; Khachatourians, George G.; Ingledew, W. M.

doi:10.1128/aem.44.3.747-750.1982

Cited by 24 publications

(3 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Amylase production by the isolates was evaluated by inoculating 1 μl of each isolate on Horikoshi II solid medium [15] (pH 10.5) and incubating at 37 o C for 72 h. The assay plate was flooded with Gram's iodine (1.27g iodine in 10 ml distilled water containing 2 g potassium iodide, and diluted to 300ml with distilled water) dye solution and the presence of halos around the colonies used as an indication of amylase producing isolates [16].…”

Section: Screeningmentioning

confidence: 99%

Protease-, Pectinase- and Amylase- Producing Bacteria from a Kenyan Soda Lake

Oluoch¹,

Okanya²,

Hatti‐Kaul³

et al. 2018

TOBIOTJ

View full text Add to dashboard Cite

Background: Alkaline enzymes are stable biocatalysts with potential applications in industrial technologies that offer high quality products. Objective: The growing demand for alkaline enzymes in industry has enhanced the search for microorganisms that produce these enzymes. Methods: Eighteen bacterial isolates from Lake Bogoria, Kenya, were screened for alkaline proteases, pectinases and amylases; characterized and subjected to quantitative analysis of the enzymes they produced. Results: The screening analysis ranked 14, 16 and 18 of the bacterial isolates as potent producers of alkaline proteases, pectinases and amylases, respectively. The isolates were classified into two groups: Group 1 (16 isolates) were facultatively alkaliphilic B. halodurans while group 2 (2 isolates) were obligately alkaliphilic B. pseudofirmus. Further analysis revealed that group 1 isolates were divided into two sub-groups, with sub-group I (4 isolates) being a phenotypic variant sub-population of sub-group II (12 isolates). Variation between the two populations was also observed in their enzymatic production profiles e.g. sub-group I isolates did not produce alkaline proteolytic enzymes while those in sub-group II did so (0.01-0.36 U/ml). Furthermore, they produced higher levels of the alkaline pectinolytic enzyme polygalacturonase (0.12-0.46 U/ml) compared to sub-group II isolates (0.05-0.10 U/ml), which also produced another pectinolytic enzyme - pectate lyase (0.01 U/ml). No clear distinction was however, observed in the production profiles of alkaline amylolytic enzymes by the isolates in the two sub-populations [0.20-0.40 U/ml (amylases), 0.24-0.68 U/ml (pullulanases) and 0.01-0.03 U/ml (cyclodextrin glycosyl transferases)]. On the other hand, group 2 isolates were phenotypically identical to one another and also produced similar amounts of proteolytic (0.38, 0.40 U/ml) and amylolytic [amylases (0.06, 0.1 U/ml), pullulanases (0.06, 0.09 U/ml) and cyclodextrin glycosyl transferases (0.01, 0.02 U/ml)] enzymes. Conclusion: The facultatively alkaliphilic B. halodurans and obligately alkaliphilic B. pseudofirmus isolates are attractive biotechnological sources of industrially important alkaline enzymes.

show abstract

Section: Screeningmentioning

confidence: 99%

Protease-, Pectinase- and Amylase- Producing Bacteria from a Kenyan Soda Lake

Oluoch¹,

Okanya²,

Hatti‐Kaul³

et al. 2018

TOBIOTJ

View full text Add to dashboard Cite

show abstract

“…For amylase, the plates contained 1% starch. Transparent or yellowish haloes were visible on a dark-violet background by flooding with lugol (Dahwale et al, 1982). Pectinase was assayed in plates with 1% pectin.…”

Section: Enzymatic Assaysmentioning

confidence: 99%

Untitled

2018

Int. J. Curr. Res. Biosci. Plant Biol.

View full text Add to dashboard Cite

The presence in oil-contaminated soils of an abundant oil-degrading indigenous microbiota, able to hydrolyze additionally a diversity of bio-polymers by secreting specific enzymes, could explain in part the efficient bioremediation generally observed when oil-polluted soils are composted with a variety of bio-organic wastes. The present study achieved in 12 oil-contaminated soils, demonstrated in all cases their unsuitable nutrient content; however, their oil-degrading bacterial counts fluctuated mainly between 10 6 -10 7 c.f.u./g soil. The exoenzymatic profile studied in 100 hydrocarbon-degrading bacteria isolated from such soils, gave a percent frequency of positivity of amylases 75, lipases 73, keratinases 67, caseinases 61, elastases 36, chitinases 34, lecithinases 30, chitosanases 25, DNases 19, pectinases 15, cellulases 7 and esterases 6. Most of these isolates (90%) produced 2-5, but some can secrete until 8-10 different exoenzymes.

show abstract

“…These methods are classified into two sub-categories, the chromogenic and saccharogenic approaches, according to analytical approach. In chromogenic methods, the release amounts of soluble dye are directly measured from covalently chemical-modified starch or maltosaccharide substrates, such as Cibacron Blue F3 G-A cross-linked starch [24] or nonreducing end-blocked 2-chloro- p -nitrophenyl maltohepotosides (Gal-G2-CNP) [25]. Chromogenic methods are simple, reliable, and sensitive for α-amylase determination, but are extremely expensive because they require a synthetic substrate and specific enzymes.…”

Section: Introductionmentioning

confidence: 99%

Hand-held Colorimetry Sensor Platform for Determining Salivary α-Amylase Activity and Its Applications for Stress Assessment

Hsiao

Chen

Chou

et al. 2019

Sensors

View full text Add to dashboard Cite

This study develops a hand-held stress assessment meter with a chemically colorimetric strip for determining salivary α-amylase activity, using a 3,5 dinitrosalicylic acid (DNS) assay to quantify the reducing sugar released from soluble starch via α-amylase hydrolysis. The colorimetric reaction is produced by heating the strip with a mini polyester heater plate at boiling temperature to form a brick red colored product, which measured at 525 nm wavelength. This investigation describes in detail the design, construction, and performance evaluation of a hand-held α-amylase activity colorimeter with a light emitted diode (LED) and photo-detector with built-in filters. The dimensions and mass of the proposed prototype are only 120 × 60 × 60 mm3 and 200 g, respectively. This prototype has an excellent correlation coefficient (>0.995), comparable with a commercial ultraviolet–visible spectroscope, and has a measurable α-amylase activity range of 0.1–1.0 U mL−1. The hand-held device can measure the salivary α-amylase activity with only 5 μL of saliva within 12 min of testing. This sensor platform effectively demonstrates that the level of salivary α-amylase activity increases more significantly than serum cortisol, the other physiological stressor biomarker, under physiologically stressful exercise conditions. Thus, this work demonstrates that the hand-held α-amylase activity meter is an easy to use and cost-effective stress assessment tool for psychoneuroendocrinology research.

show abstract

Improved Method for Detection of Starch Hydrolysis

Cited by 24 publications

References 17 publications

Protease-, Pectinase- and Amylase- Producing Bacteria from a Kenyan Soda Lake

Protease-, Pectinase- and Amylase- Producing Bacteria from a Kenyan Soda Lake

Untitled

Hand-held Colorimetry Sensor Platform for Determining Salivary α-Amylase Activity and Its Applications for Stress Assessment

Contact Info

Product

Resources

About