# Ultrasound-Assisted Extraction of Bioactives from Spirulina platensis: Optimization and Prediction of Their Properties Using Near-Infrared Spectroscopy Coupled with Artificial Neural Network Modeling

## TL;DR

This study improves the extraction of valuable compounds from Spirulina using ultrasound and introduces a fast method to predict their properties using light and AI.

## Contribution

A novel combination of UAE optimization and NIR-ANN modeling for rapid, non-destructive analysis of Spirulina bioactives.

## Key findings

- Optimal UAE conditions achieved high yields of polyphenols, proteins, and C-phycocyanin with strong antioxidant activity.
- NIR spectroscopy with ANNs accurately predicted key properties like L* and TDS with RPD values of 3.9064 and 2.8351.
- The method is scalable and reproducible, offering a significant improvement for industrial quality control.

## Abstract

This study optimizes the ultrasound-assisted extraction (UAE) of bioactive compounds from Spirulina platensis and develops a rapid, non-destructive analytical method. A Box–Behnken design and desirability function were used to find the optimal extraction conditions to simultaneously maximize total polyphenols, proteins, C-phycocyanin, and antioxidant activity. The optimal conditions were a solid-to-liquid ratio of 35 g/L, a time of 20 min, a pH of 10, and a temperature of 45 °C. Independent validation confirmed the model’s reliability, with experimental results closely matching predicted values. Furthermore, Near-Infrared (NIR) spectroscopy, combined with Artificial Neural Networks (ANNs), was explored as a predictive tool. The models, particularly those based on a semi-process NIR spectrometer, showed excellent predictive capabilities for key physicochemical properties, with an RPD of 3.9064 for L* and 2.8351 for TDS. This research establishes a highly reproducible and scalable extraction protocol, complemented by a fast and accurate analytical method, providing a significant advancement for the industrial application and quality control of Spirulina platensis extracts.