Biochemical characterization of sap (latex) of a few Indian mango varieties

• Published in: Phytochemistry (Oxford) 2003, Vol.62 (1), p.13-19
• Main Authors: Saby John, K., Bhat, S.G., Prasada Rao, U.J.S.
• Format: Article
• Language: English
• Subjects: Agronomy. Soil science and plant productions; Biological and medical sciences; Carbohydrate; Carbohydrate Metabolism; Carbohydrates - analysis; Catechol Oxidase - analysis; Catechol Oxidase - metabolism; Chemical constitution; Crosses, Genetic; Economic plant physiology; Endopeptidases - analysis; Endopeptidases - metabolism; Flavonoids; Fruit - chemistry; Fruit - enzymology; Fruit - growth & development; Fundamental and applied biological sciences. Psychology; India; Latex - chemistry; Latex - isolation & purification; Mangifera - chemistry; Mangifera - enzymology; Mangifera - growth & development; Mango; Peroxidase; Peroxidase - analysis; Peroxidase - metabolism; Phenols - analysis; Plant physiology and development; Polymers - analysis; Polyphenol oxidase; Polyphenols; Protein; Sap
• ISSN: 0031-9422; 1873-3700
• DOI: 10.1016/S0031-9422(02)00441-7

Mango sap (latex) from four Indian varieties was studied for its composition. Sap was separated into non-aqueous and aqueous phases. Earlier, we reported that the non-aqueous phase contained mainly mono-terpenes having raw mango aroma (Phytochemistry 52 (1999) 891). In the present study biochemical composition of the aqueous phase was studied. Aqueous phase contained little amount of protein (2.0–3.5 mg/ml) but showed high polyphenol oxidase (147–214 U/mg protein) and peroxidase (401–561 U/mg protein) activities. It contained low amounts of polyphenols and protease activities. On native PAGE, all the major protein bands exhibited both polyphenol oxidase and peroxidase activities. Both polyphenol oxidase and peroxidase activities were found to be stable in the aqueous phase of sap at 4 °C. Sap contained large amount of non-dialyzable and non-starchy carbohydrate (260–343 mg/ml sap) which may be responsible for maintaining a considerable pressure of fluid in the ducts. Thus, the mango sap could be a valuable by-product in the mango industry as it contains some of the valuable enzymes and aroma components. Mango sap contained very little protein but most of the protein was associated with polyphenol oxidase and peroxidase activities. Sap also contained a large amount of non-dialysable, non-starchy carbohydrate which may be responsible for maintaining the sap at considerable pressure in the duct system.