MJSTEM

Abstract

Natural dyes have attracted increasing attention as environmentally friendly alternatives to synthetic chromosome stains because of their low toxicity, biodegradability, and availability from renewable resources. However, comparative quantitative evidence regarding the chromosome staining performance of locally available pigment-rich plants remains limited. This study aimed to evaluate the effectiveness of chromosome dyes extracted from five plant species, namely black glutinous rice (Oryza sativa L.), dried roselle (Hibiscus sabdariffa L.), ripe karanda fruit (Carissa carandas L.), red dragon fruit (Hylocereus polyrhizus), and bougainvillea (Bougainvillea spectabilis). Plant materials were extracted with distilled water at a ratio of 10 g:100 mL by heating at 40–60°C for 20 min. Chromosome preparations were obtained from onion (Allium cepa L.) root tips using the squash technique and stained with each plant extract. Microscopic images were captured under identical conditions at 100× magnification and quantitatively analyzed using ImageJ software. Ripe karanda fruit extract produced the highest chromosome image clarity value (47.770 ± 1.191), followed by black glutinous rice (42.427 ± 4.838), dried roselle (40.762 ± 3.511), bougainvillea (32.349 ± 2.500), and red dragon fruit (20.848 ± 2.934). Anthocyanin-rich extracts generally exhibited superior staining performance compared with betalain-rich extracts. These findings demonstrate that ripe karanda fruit, black glutinous rice, and dried roselle possess considerable potential as inexpensive, environmentally friendly chromosome stains for cytogenetic education and laboratory applications. The integration of natural pigment extraction with ImageJ-based quantitative image analysis also provides an objective and reproducible approach for evaluating the performance of sustainable biological stains.

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