Naringin analysis

Calculations. Record the weight of the pulp in grams. Naringin Analysis (Davis Test)... 

Widmer, W.W. and Martin, S.F., Interferences with naringin and neohesperidin analysis by high performance liquid chromatography, Proc. Flo. Hort. Soc., 105, 149, 1992. 

McIntosh CA, Mansell RL (1997) Three-dimensional analysis of Umonin, Umonoate a-ring monolactone, and naringin in the fruit of three varieties of Citrus paradisi. 1 Agric Food Chem 45 2876-2883... 

Mansell RL, McIntosh CA, Vest SE (1983) An analysis of the Umonin and naringin content of grapefruit juice samples collected from florida state test houses. 1 Agric Food Chem 31 156-162... 

Spices (rosemary, sage, thyme) contain considerable amounts of flavonols and flavones, mainly in the glycoside form (154). Thus, phenolic analyses in spices were often considered in order to determine the optimum time for plant collection to give maximum flavonoid contents and for health benefits (154,155). Flavonoids (naringin, luteolin, apigenin, and chrysoeriol) were extracted from spices using a percolation process at room temperature with solvents (MeOH and EtOAc), and HPLC analysis was carried out (155). 

He suggested that the method might also be suitable for the determination of flavones and flavonols. This method is still widely used to measure naringin in grapefruit juice albeit it is not specific for naringin, it is a simple, rapid and inexpensive method of analysis. However, since grapefruit contains both bitter and nonbitter flavanone glycosides, Davis values are only a crude approximation of bitterness. 

However, HPLC is not without its drawbacks 1) equipment cost is very high (thus small processing operations would probably be unable to purchase and maintain such an instrument) 2) only one compound can be measured at a time since different columns and solvents are used for each class of compounds (this also means that time must be spent in changing the system from one analysis to the next) 3) pre-purification is required and for good resolution repeated liquid-liquid and evaporation steps are involved 4) the procedure is slow (only 10-15 samples can be processed per person per day) 5) it is sensitive only to the parts per million (ppm) range (pg/gm). Thus, in summing the current status of limonin and naringin quantification, a quotation is most appropriate. 

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