Green Extraction of Carotenoids from Tomato By-products Using Sodium Dodecyl Sulphate

What if the key to unlocking nature's most vibrant antioxidant lies not in toxic solvents, but in a biodegradable soap? Tomato peels, a by-product of the food industry, hide a treasure trove of lycopene—and scientists have found a greener way to extract it.

Tomato peels, often discarded as waste, are packed with lycopene—a powerful antioxidant linked to numerous health benefits. Traditionally, extracting this compound has relied on harsh organic solvents, which are neither eco-friendly nor sustainable. But a recent study flips the script, using a biodegradable anionic surfactant called sodium dodecyl sulphate (SDS) to achieve a green extraction.

The researchers employed a Plackett–Burman design to screen seven factors affecting carotenoid extraction, from SDS concentration to homogenisation speed. They found that SDS volume, ultrasound use, and extraction time were the most influential, then fine-tuned these using a Box–Wilson design. The final protocol involved just 1 gram of sample, 11.9 ml of 0.3% SDS, homogenisation at 13,500 rpm for 2 minutes, an ultrasound phase, and 8.2 hours of agitation.

After quantifying the extracts with UV–VIS and HPLC-DAD, they confirmed high lycopene purity via nuclear magnetic resonance. Even more intriguing, transmission electron microscopy revealed intact chromoplasts—the cellular compartments that hold carotenoids—acting as natural shields against external degradation. This means the extracted lycopene is not only pure but also protected.

This work demonstrates that SDS is a viable, degradable alternative for extracting liposoluble bioactives like lycopene. The resulting extract could enrich new foods or serve as a base for nutraceuticals, turning waste into wellness—sustainably.

Key Points

• Green extraction using biodegradable surfactant SDS
• Optimized protocol: 1 g sample, 0.3% SDS, 8.2 h
• High lycopene purity, intact chromoplasts protect