000			01820nam a2200181Ia 4500
003			MX-MdCICY
005			20250625140637.0
040			_cCICY
090			_aB-10734
245	1	0	_aReevaluation of the Phenol-Sulfuric Acid Reaction for the Estimation of Hexoses and Pentoses
490	0		_vAnalytical BioChemistry, 181, p.18-22, 1989
520	3		_aEvidence is provided to show that in the conventional phenol-sulfuric acid reaction procedure, phenol underwent sulfonation in situ and the phenolsulfonic acid formed decreased the color intensity for hydroxymethyl furfural (HMF), furfural, and many hexoses and pentoses tested. A modified method is described to overcome this problem in which phenol was added after the dehydration of carbohydrates by sulfuric acid and after cooling the system. The color intensity around 476-485 nm for different compounds was fairly proportional to the amount of furfural derivatives (absorption at 310-320 nm)formed from the sugars in the modified method unlike in the conventional procedure. The studies also show that for condensation of HMF derivatives with phenol, heat is not necessary. The color intensity in the modified method also increased compared to that in the conventional method. The increase in the modified method compared to that in the conventional method was 6.0-fold for furfural, 9.1-fold for hydroxymethyl furfural, 3.7-fold for fructose, 2.3-fold for xylose, and 2.0-fold for glucose and arabinose. The possible reasons for this differential increase are discussed.
700	1	2	_aRao, P.
700	1	2	_aPattabiraman, T.N.
856	4	0	_uhttps://drive.google.com/file/d/1O6MABdZv4hjMJ-xP7H_tgOOOLHgaxff_/view?usp=drivesdk _zPara ver el documento ingresa a Google con tu cuenta: @cicy.edu.mx
942			_2Loc _cREF1
008			250602s9999 xx |||||s2 |||| ||und|d
999			_c44966 _d44966