1.DETERMINATION OF PANTOTHENIC ACID IN INFANT FORMULA BY HPLC
Acta Nutrimenta Sinica 1956;0(03):-
The determination of pantothenic acid in infant formula was carried out by means of HPLC. The sample was dissolved in deionizid water and put in an ultra-sonic generator for 15 minutes, adjust pH to precipitate protein. After centrifugation the supernatants were used as test sample for HPLC analysis. Column: Bondapak C18, Detector: ultraviolet 200nm, and 0.01M KH2PO4/CH3OH as eluant. Coefficient of variation was 6.58% and recovery was 93.78%.The method might be applicable to milk and milk products and alsoto the samples containing free pantothenic acid such as wheat germ and flour.
2.QUANTITATIVE DETERMINATION OF VITAMIN D IN FORTIFIED INFANT MILK DOWDER BY MEANS OF HPLC
Xiaoning LI ; Lijuan ZHANG ; Jingshan ZUO
Acta Nutrimenta Sinica 1956;0(01):-
The determination of vitamine D in fortified milk powder was carried out by means of HPLC. Its pre-treatments include extraction of fat, sap onification, isolation of the unsaponifiable matters, and digitonin-celite and bentonite column chromatography. The HPLC was performed with 15cm ? 4mm column of silica 5m 0.7% ethyl alcohol in iso-octane as mobile phase, at 254nm. Only 12 grams of sample which contained 400-500 IU vitamin D/100 g were used. Within the sample there were relatively large amounts of interfering materials such as fats, sterols,?-carotene, vitamin A, vitamin E and their decomposed products, but they could be separated by the above method. The recovery rate of vitamin D was 81% with standard deviation of 0.39?g/100g. This method could also be applied to other samples such as fortified cakes, confectionaries, infant foods and "Mairujing" (milk maltose mixture powder) etc.
3.DETERMINATION OF VITAMIN E IN PEANUT OIL AND SOME FOODS BY FLUOROMETER AND TLC SCANNER
Jingshan ZUO ; Lijuan ZHANG ; Ziqian CHEN ; Weilun KE
Acta Nutrimenta Sinica 1956;0(03):-
Vitamine E in peanut oil was determined by means of f Juorometric method (Ex = 285nm, Em=324nm) and TLC scanning method (? = 292nm). Both methods include saponification of the oil, isolation o'f the unsaponifiable matters and the respective final measurements. The result of the former method indicates the total vitamine E in terms of ?-vitamine E and the latter method may indicate their ?,?,? and 6 analogues separately. These two methods are simple, time-saving and reliable. The recovery of VE and the standard deviation of replication of fluorometric method and TLC scanning method are 99.3%, ? 0.587mg/100g sample and 103.04%, ?0.959mg/100g sample respectively. Both methods are also applicable to other foods such as fortified cakes, confectionaries, infant foods etc., but the oil in these samples must be extracted before saponification.