Basella Rubra Fruit Extract

2916 Words Jul 12th, 2013 12 Pages
The Effectiveness of Basella rubra (Alugbati) Fruit Extract as a Counterstain in Gram Staining

Investigators:

Astilla, Yasmin Marie
Cala, Maria Victoria Bianca
Ko, Mariell
Lizardo, Francis Dominic
Mariano, Maria Cristina
Querol, Maria Zennah
Quinto, Camille
Rosales, Ana Mariella
Valmonte, Kyla Nicole
Villalon, Gian Angelo

4MT-2

Statement of the Problem

Can Basella rubra fruit extract be used as a counterstain in Gram staining?

Introduction & Background

According to H. J. Croxx, when microscopists first began to use stains in the sixties and seventies, the demand for dyes for this purpose was naturally too small to justify a special source of supply. They therefore had to make use of textile dyes, which were then very crude and
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According to Francis (1992), anthocyanins are glycosylates from anthocyanidins, the nucleus of which is the structure of a 4'-hidroxiflavilum ion. All anthocyanins are composed of two or three parts: the basic structure, which is aglycone (anthocyanidin), sugar and frequently an acyl group. According to Hidrazina (1982), anthocyanins are responsible for the blue, red, violet and purple coloration in most species of plant kingdom. According to Mazza (1995), anthocyanins predominantly exist in their non-colored forms in neutral to slightly acidic pH.

According to Brouillard (1982), anthocyanins are more stable in acidic than in neutral or alkaline solutions. One of the main characteristics of anthocyanins is the change in solution coloration in response to the pH of the environment. The color and stability of an anthocyanin in solution is highly dependent on pH. Anthocyanins are most stable and most highly colored at low pH values and gradually lose color as the pH increases, becoming almost colorless between pH 4.0 and 5.0. This color loss is reversible and the red hue will return upon acidification; which makes it suitable as a counterstain in Gram staining.
Natural stains are best known for its distinct property: permanence of…