# Physicochemical, Structural, Molecular, and Thermal Characterization of Fucus vesiculosus Extract-Based Nanofibrous Mats

## TL;DR

This study creates and analyzes nanofibrous mats made from Fucus vesiculosus and zein, showing their potential for delivering bioactive compounds in food applications.

## Contribution

The first design of Fucus vesiculosus:zein nanofibrous mats using electrospinning, demonstrating enhanced stability and bioactivity.

## Key findings

- Changing polymer ratios affects fiber diameter, surface area, and pore characteristics.
- FV:Z mats showed high levels of phenolic compounds like hydroxycinnamic and quercetin.
- Thermal stability and bioactivity improved with intermolecular interactions in the mats.

## Abstract

Ratios of 3:1 and
4:1 Fucus vesiculosus:zein (FV:Z) containing
nanofibrous mats were designed for the first
time by the electrospinning method. According to the results, electrical
conductivity, surface tension, viscosity, and density are proportional
to each other. Scanning electron microscopy (SEM) images depicted
morphology, revealing the presence of homogeneous nanostructures.
Changing the polymer ratios altered the fiber diameter, specific surface
area, pore volume, and pore size. Average values of hydroxycinnamic
(21.5 μgmg–1), quercetin (19.8 μgmg–1), and caffeic (16.23 μgmg–1) were determined to be the highest phenolic compounds in the HPLC
chromatogram, serving as an important source of bioactive ingredients
for food applications. Total IC50 values of FV:Z 3:1 and FV:Z 4:1
mats were 46.37 μgml–1 and 46.90 μgml–1, respectively. Total phenolic content (TPC) is also
presented at higher levels in all of the ABTS and DPPH assays. Determination
of the H atom in the −OH group and the carbonyl group of a
carboxylic acid group of phenolic acid in the FTIR spectrum was consistent
with the ABTS and DPPH results. In the FTIR spectra for nanofibrous
mats, vibrations shifted toward smaller wavenumbers with stronger
ionic interaction compared to the FV extract. Slightly shifted and
increased peaks were observed in the spectra, confirming successful
interaction between Fucus and zein. Functional groups (NH2, COOH, and OH) allow intermolecular interactions such as H bonding.
π–π stacking, π alkyly, and sulfur-containing
products are detected. TGA and DSC results showed that the thermal
stability of nanoencapsulated FV bioactive compounds strengthened
at higher temperatures. Differences in XRD crystal patterns, such
as changes in the intensities of diffraction peaks, were also recognized
between samples. Overall, stability and bioactivity improved with
the formation of inter/intramolecular associations. Results indicated
that nanofibrous mats have potential in the nanoencapsulation and
delivery of bioactives.