Fabrication and characterization of novel polyvinylpyrrolidone nanocomposites having SiO2 nanoparticles modified with citric acid and L(+)-ascorbic acid

Fruit quality of 24 selected strawberry cultivars and selections were evaluated. There were great variations in the contents of soluble solids, titratable acidity, carbohydrates, organic acids, and ascorbic acid among different cultivars, reflecting primary genetic differences. Fructose, glucose, and sucrose were found to be the three major sugars, comprising >65% of the total soluble solids in strawberry. Fruit contained lower sucrose compared to fructose and glucose, whereas leaves contained comparable amounts of fructose, glucose, and sucrose. Citric acid was the major organic acid in strawberries. Strawberries were also rich in ascorbic acid. Leaves were much higher in ascorbic acid than fruit. There appeared to be no correlation between fruit and leaves on carbohydrate, organic acid, and ascorbic acid contents.

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Fabrication and characterization of elastomeric scaffolds comprised of a citric acid-based polyester/hydroxyapatite microcomposite

Materials & Design (1980-2015) ◽

10.1016/j.matdes.2013.03.026 ◽

2013 ◽

Vol 50 ◽

pp. 446-450 ◽

Cited By ~ 19

Author(s):

Ali Moradi ◽

Adel Dalilottojari ◽

Belinda Pingguan-Murphy ◽

Ivan Djordjevic

Keyword(s):

Citric Acid ◽

Fabrication And Characterization

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Purification and characterization of the polyphenoloxidase (PPO) isolated from Solenocera crassicornis (H. Milne Edwards, 1837)

Crustaceana ◽

10.1163/15685403-00003412 ◽

2015 ◽

Vol 88 (3) ◽

pp. 259-272 ◽

Cited By ~ 1

Author(s):

X. W. Xiang ◽

Y. F. Zhou ◽

Y. B. Hao ◽

H. C. Yang ◽

H. W. Ma ◽

...

Keyword(s):

Ascorbic Acid ◽

Citric Acid ◽

Ethylenediaminetetraacetic Acid ◽

Gel Filtration ◽

Catechol Oxidase ◽

Specific Substrate ◽

Purification And Characterization ◽

Sds Page ◽

Optimal Ph

Polyphenoloxidase (PPO) from Solenocera crassicornis (H. Milne Edwards, 1837) was partially purified through ion-exchange and gel-filtration chromatography, and its enzymatic properties were also characterized using l-dihydroxyphenylalanine (L-DOPA) as the specific substrate. The molecular mass of PPO in SDS-PAGE is about 66.5 kDa, and the PPO molecule isolated by HPLC, is 133 kDa, implying it is a homodimeric protein. The optimal pH and temperature of PPO activity was 6.5 and 40°C, and the value was 3.80 and 8.12 on L-DOPA and on catechol, respectively. It was found that the purified PPO could only catalyse o-diphenol substrates, inferring that it belongs to the catechol-oxidase family. The PPO was very sensitive to phenylthiourea, ascorbic acid, citric acid and cysteine. The PPO activity was strongly inhibited by ethylenediaminetetraacetic acid (EDTA), Cu2+ and Zn2+, indicating that Solenocera crassicornis PPO is most probably a copper-containing metalloenzyme.

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