Extraction and Physiochemical Characterization of Natural Colorant from Monotheca buxifolia for Industrial Applications

Abstract

Currently, many industries prefer to use natural dyes instead of synthetic ones due to safety, health, and ecological concerns. This study aimed to extract, apply and characterize two natural colors from the fruits of Monotheca buxifolia through phytochemical screening, UV vis-spectrophotometry, FTIR, and GCMS techniques and assessing antimicrobial activity. It is widely distributed in Khyber Pakhtunkhwa and Balochistan in Pakistan, proposing an eco-friendly and sustainable dyeing solution for food industry. Gravimetric analysis indicates that among all the extraction methods, the ultrasound extraction method yields a high percentage, followed by maceration extraction. The natural color extracted via the ultrasound method demonstrates high ash content, carbohydrates, flavonoids, phenolics, and antibacterial properties, surpassing the natural color extracted by maceration, which exhibits a high anthocyanin content. GC-MS results showed presence of some compounds with intense color yielding properties in both natural colors. FTIR analysis identifies alcohols, alkanes, aldehydes, ketones, sulfones and ethers as major functional groups. Furthermore, the application of the dye in food products (jelly candies, cream, and hard candies) was tested for color efficiencies in terms of CIE L* a* b* values. Color efficiencies of both natural colors in hard candies were evaluated through color analysis, moisture content, ash tests, estimation of flavonoids and phenolics, BRIX value, solubility time, antibacterial, and antifungal activity. A comparison of both candies reveals that SQ1 candy has higher moisture, ash, flavonoid and phenolic content. Both candies exhibit similar BRIX values and solubility times, with highest zone of inhibition showed by SQ1 candy against S. aureus bacteria. Results indicate that both candies lack antifungal xvi properties. The overall results suggest that the fruit extract of monotheca buxifolia is suitable for manufacturing ecofriendly colors for different industries, like pharmaceuticals, foods and cosmetics, as a safer and sustainable alternative to non-biodegradable synthetic dyes.