Questions and Answers (7) View all
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Answer added in Food Chemistry6 Why MUFA and PUFA are not tested for oil quality analysis instead of FFA??By Swarnali Dutta Majumdar · M.O.P.Vaishnav College for WomenNathachai Tiengburanatam ·There are many reasons for that. Firstly, MUFA and PUFA usually present in mixture (not pure), so it is difficult to determine (also difficult to sepa... [more]There are many reasons for that. Firstly, MUFA and PUFA usually present in mixture (not pure), so it is difficult to determine (also difficult to separate them) each of them in mixture. For example, when the test result exhibit 100 unsat bonds (suppose by I no.) and you know your sample contain 100 FFA. It does not mean that each of your FFA contains one double bond only. 50 of your FFAs may possibly contain two double bond each while the other are sat and so on.... Secondly, both MUFA and PUFA are all vulnerable to normal environments and their amount usually change quickly. So, your measured value at last 2-3 hours may not true now. Thirdly, both of them are not significantly different in health benefits (unlike sat vs. unsat.) and processing outcomes. I think that many other reasons should remain. ....Following
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Answer added in Chemistry16 Determinating Polar Compounds in samples of frying oils, how to make standard samplesBy Ana Fernandes · Universidade do MinhoTitus is right. Most of toxic compounds are relatively non-polar and (for aromatic compound) the fluorescence monitoring is a good way.Titus is right. Most of toxic compounds are relatively non-polar and (for aromatic compound) the fluorescence monitoring is a good way.Following
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Answer added in Chemistry16 Determinating Polar Compounds in samples of frying oils, how to make standard samplesBy Ana Fernandes · Universidade do MinhoLipid or oil (I mean triglyceride) is quite non-polar, but it will tern to be more polar after oxidation which generates many polar compounds (mostly ... [more]Lipid or oil (I mean triglyceride) is quite non-polar, but it will tern to be more polar after oxidation which generates many polar compounds (mostly are small fatty acids and free radicals) within such oil. Exposing to oxygen and some catalysts (iron, hydrogen peroxide, oxidase, etc) will accelerate the deteriorate mechanism very very faster. So, you can add small fatty acids (such as propionic acid, butanoic acid, valeric acid or pentanoic acid, hexanoic acid) into your oils to make standard you need. Your comparison should be resulted in equivalent value because the products in real reaction are occurred randomly. ^^...Following
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Answer added in Food Chemistry13 Which method is suitable for preparation of resistant starch from starch?By Koteswara Reddy · Pondicherry UniversityDepend on your starch sources and target properties. What you must know first are; your modified starch need to be soluble or not, what to resist (nor... [more]Depend on your starch sources and target properties. What you must know first are; your modified starch need to be soluble or not, what to resist (normal digestive enzymes, microbial enzymes, physical factors, etc), and your available facilities (also budget) to modify them.Following
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Answer added in Biotechnology4 What is the criteria for distinguishing between safe and unsafe biotechnological products?That is a good idea. Thank for your comment, Mr. Mohammed..... We must save their lives (or also pain) as high as we can do.That is a good idea. Thank for your comment, Mr. Mohammed..... We must save their lives (or also pain) as high as we can do.Following
Publications (2) View all
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Article: Zingipain, A cysteine protease from Zingiber ottensii Valeton rhizomes with antiproliferative activities against fungi and human malignant cell lines.
Aphichart Karnchanatat, Nathachai Tiengburanatam, Apaporn Boonmee, Songchan Puthong, Polkit Sangvanich[show abstract] [hide abstract]
ABSTRACT: The objective of this study was to investigate the activity of a protein identified as cysteine protease, purified from Zingiber ottensii Valeton rhizomes, in terms of antiproliferation against fungi, bacteria, and human malignant cell lines. By means of buffer extraction followed by (NH(4))(2)SO(4) precipitation and ion-exchange chromatography, the obtained dominant protein (designated F50) was submitted to non-denaturing and reducing sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), where a single band and three bands were revealed from eletrophoretic patterns, respectively. It could be concluded at this point that the F50 was potentially a heterotrimer or heterodimer composed of either two small (∼13.8 and ∼15.2 kD) subunits or these two together with a larger (∼32.5 kD) one. In-gel digestion was carried out for the most intense band from reducing SDS-PAGE, and to the resulting material was applied liquid chromatography (LC)-mass spectroscopy (MS)/MS. The main F50 subunit was found to contain fragments with 100% similarity to zingipain-1, a cysteine protease first discovered in Zingiber officinale. The activity corresponding to the identified data, cysteine protease, was then confirmed in the F50 by azocasein assay and a positive result was obtained. The F50 then was further investigated for antiproliferation against three plant pathogenic fungi species by disk diffusion test, four bacterial species by direct exposure in liquid culture and dish diffusion tests, and five human malignant cell lines by tissue culture assay. It was found that a dose of 23.6 µg F50/0.3 cm(2) of paper disk exhibited the best inhibitory effect against Collectotrichum cassiicola, while lesser effects were found in Exserohilum turicicum and Fusarium oxysporum, respectively. No inhibitory effect against bacterial proliferation was detected in all studied bacterial strains. However, relatively strong antiproliferative effects were found against five human cell lines, with IC50 values ranging from 1.13 µg/mL (hepatoma cancer; HEP-G2) to 5.37 µg/mL (colon cancer; SW620). By periodic acid-Schiff's staining and phenol-sulfuric acid assay, the F50 was determined as a glycoprotein containing 26.30 ± 1.01% (by weight) of carbohydrate. Thus, a new glycoprotein with protease activity was successfully identified in Zingiber ottensii rhizome. The glycoprotein also contained antiproliferative activity against some plant pathogenic fungi and human cancer cell lines.Preparative Biochemistry & Biotechnology 04/2011; 41(2):138-53. · 0.47 Impact Factor -
Article: A novel α-glucosidase inhibitor protein from the rhizomes of Zingiber ottensii valeton.
[show abstract] [hide abstract]
ABSTRACT: The objective of this study was to investigate a new protein with α-glucosidase inhibitory activity from the rhizomes of Zingiber ottensii. With a simple salting-out technique followed by single-step anion-exchange purification, the protein was successfully purified from the rhizomes. This protein was found to have three likely sub-unit types, 32.5, 15.2, and 13.8 kDa, as revealed by native and reducing SDS-PAGE analysis. Determination of the kinetics of the inhibition of α-glucosidase from Saccharomyces cerevisiae by standard enzymatic methods indicated the maximum percent inhibition; IC(50) and K ( i ) of this protein were 77.5%, 30.15 μg/ml, and 140 μmol, while the K ( m ) and V ( max ) were 2.35 μmol and 0.11 mM/min, respectively. The inhibitory action was pH-independent within the pH range 2-10, but was potentially affected by buffer salts, and was relatively temperature-stable between 4-35 °C, with a maximum activity at 65 °C. The amino acid sequence of an internal fragment of this purified Z. ottensii rhizomal protein had a similarity to the sequence from the plant cysteine proteinase family. Although this α-glucosidase inhibitory protein was purified from Z. ottensii rhizomes and preliminarily characterized, further studies are needed prior to firm applications being envisaged.Applied biochemistry and biotechnology 04/2010; 162(7):1938-51. · 1.94 Impact Factor