# Microencapsulation of Black Carrot Pomace Bioactive Compounds: Artificial Neural Network Modeling of Cytotoxicity on L929 Fibroblast Cells

## TL;DR

This study explores sustainable methods to extract and encapsulate bioactive compounds from black carrot pomace, showing they are safe and could be used in functional foods and biomedical products.

## Contribution

The study introduces a sustainable method combining ultrasonic extraction and freeze-drying with gum Arabic to preserve bioactive compounds from black carrot pomace.

## Key findings

- Both liquid and powder formulations of black carrot pomace were biocompatible and even stimulated cell growth in L929 fibroblast cells.
- Artificial Neural Network models effectively described the dose- and time-dependent viability patterns of the formulations.
- FD-BCP showed partial encapsulation of phenolic compounds, maintaining their structural integrity as confirmed by SEM and FTIR.

## Abstract

Valorization of black carrot pomace (BCP), an industrial by-product rich in bioactive compounds, was performed using sustainable extraction and formulation approaches. Bioactive compounds were extracted, using water as a solvent, via ultrasonic processing. The resulting liquid extract (BCP-E) was then freeze-dried with a gum Arabic gel system to obtain a powder formulation (FD-BCP). The technological, physicochemical, and bioactive characteristics of both formulations are described. Total monomeric anthocyanin and antioxidant activities (DPPH and ABTS) did not differ substantially (p > 0.05), but the liquid extract’s total phenolic content was significantly higher (4.95 mg GAE/g db) than the powder formulation’s (4.46 mg GAE/g db). While FD-BCP had three main hydrophilic phenolic compounds, suggesting partial encapsulation, high-resolution LC-MS analysis identified 21 phenolic compounds in BCP-E, dominated by chlorogenic, quinic, and protocatechuic acids. The development of a stable gum Arabic matrix that maintains the phenolics’ structural integrity was confirmed by SEM and FTIR observations. According to cytotoxicity tests conducted on L929 fibroblast cells, both formulations were biocompatible (>70% viability) and even stimulated cell growth at moderate dosages. Dose- and time-dependent viability patterns were successfully described by Principal Component Analysis and Artificial Neural Network models, highlighting the fact that formulation type is the main factor influencing biological response. Overall, ultrasonic extraction and freeze-drying offer efficient and sustainable strategies for producing stable and bioactive-rich components from black carrot pomace that may be used in functional foods and biomedical products.