Gram staining is a cornerstone technique in microbiology for the preliminary identification of bacteria, differentiating them into Gram-positive and Gram-negative groups based on cell wall composition [14]. Traditionally, crystal violet serves as the primary stain; however, concerns regarding its potential toxicity and environmental impact have spurred interest in natural, eco-friendly alternatives [12]. This study investigates the potential of Nephelium lappaceum (rambutan) peel extract, rich in anthocyanins, as a novel primary stain for Gram staining. Through an observational assessment, the study aims to evaluate its staining efficacy, color characteristics, and differentiation capabilities compared to conventional crystal violet. The methods would involve preparing the extract, applying it in a modified Gram staining procedure to representative bacterial cultures, and evaluating the results microscopically. Preliminary observations suggest that rambutan peel extract exhibits promising staining properties, effectively differentiating bacterial cell types. The findings highlight the potential of this natural extract as a sustainable and safer alternative, contributing to greener laboratory practices in bacterial identification.

Gram Staining, Nephelium lappaceum, Rambutan Peel, Natural Stain

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