ARS | Publication request: Total phenol content of guava fruit and development of an in vitro regeneration protocol amenable to genetic improvement

Submitted to: International Journal Food Safety, Nutrition and Public Health
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: September 21, 2011
Publication Date: December 20, 2011
Citation: Viji-Sitther, G., Harris, D.L., Dhekney, S., Bai, J., Baldwin, E.A., Yadav, A. 2011. Total phenol content of guava fruit and development of an in vitro regeneration protocol amenable to genetic improvement. International Journal Food Safety, Nutrition and Public Health. 4:225-236.

Interpretive Summary: Guava fruit are considred very nutritous due to their high vitamin C, fiber and antioxidants. Seven guava varieties, including pink- and white-fleshed guava were studied for ability to propogate (reproduce) in a Souther US climate. Antioxidant compounds were also measured.

Technical Abstract: Total soluble phenolics in two white (‘Allahabad Safeda’ and ‘Lucknow-49’), two pink (‘Beaumont’ and ‘Gushiken Sweet’), and three red fleshed (‘Ka Hua Kola’, ‘Ruby Supreme’ and ‘Red Fleshed’) guava (Psidium guajava. L.) fruits were assessed using the Folin-Ciocalteu procedure. ‘Allahabad Safeda’ and ‘Ruby Supreme’ contained the highest level of phenols (1967.5 and 1921.25 µg/g gallic acid equivalents. No significant difference in phenolic content was observed between white and red fleshed guava fruits. An in vitro method was developed for clonal propagation of ‘Lucknow-49’ and ‘Gushiken Sweet’ cultivars. Five concentrations of 6-benzylaminopurine (BAP) and kinetin (KIN) plant growth regulators were tested for in vitro regeneration. A maximum of 4.5 shoots per explant was produced on Murashige and Skoog medium supplemented with 8.9 µM BAP + 9.4 µM KIN. These studies indicate that guava, a rich source of natural phenolic antioxidants can be efficiently micropropagated for genetic studies to enhance its nutraceutical value.