Biosprospecting potential of kelp (Laminariales, Phaeophyceae) from Baja California Peninsula: phenolic content, antioxidant properties, anti-inflammatory, and cell viability

A Biorefinery Approach to the Biomass of the Seaweed Undaria pinnatifida (Harvey Suringar, 1873): Obtaining Phlorotannins-Enriched Extracts for Wound Healing

“…Fe II•mg −1 extract. These values are comparable to those of other ethanol extracts of brown seaweed, as demonstrated by Tenorio-Rodriguèz et al [33], where ethanolic extracts from Eisenia arborea showed significantly higher mean FRAP (11.9 µM FeSO 4 µg −1 ), followed by Padina concrecens (6.8 µM FeSO 4 µg −1 ), and Cystoseira osmundacea (5.4 µM FeSO 4 µg −1 ).…”

“…Figure 5 introduces the FTIR-ATR spectral analysis of the fractions wE100 (green line) and AQAE (cyan line), with a broad intense band in 3300 cm −1 region which can be assigned to hydroxyl O-H stretch in intermolecular bonded alcohols or even residual moisture. Such moiety can be found in carbohydrates and polyphenols, among other compounds [ 33 ]. The range between 2800 and 2970 cm −1 corresponds to C-H stretch vibrations, which indicate the presence of alkanes [ 33 ], which could be found in both extracts.…”

“…Such moiety can be found in carbohydrates and polyphenols, among other compounds [ 33 ]. The range between 2800 and 2970 cm −1 corresponds to C-H stretch vibrations, which indicate the presence of alkanes [ 33 ], which could be found in both extracts. AQAE fraction spectrum shows broadband at 1408 cm −1 , corresponding to sulfate S=O stretching, while wE100 presents a band at 1168 cm −1 , representative of sulfonic acid.…”

“…The band at 1733 cm −1 , in wE100, can be attributed to C=O stretching vibration of O-acetyl groups, while, at the wavenumber of 1463 cm −1 , a sharp band was found and attributed to the aromatic ring stretch (C=C). Normally, the wavenumber for this group is around 1450–1510 cm −1 [ 32 , 33 ], and in phlorotannins-enriched extracts, it has been found between 1450 and 1470 cm −1 [ 75 ]. However, Synytsya et al attributed the band at 1455 cm −1 to vibration of CH 2 to galactose and xylose and CH 3 to fucose [ 66 ], showing some possible interference of fucoidans and laminarans, typical of U. pinnatifida .…”

“…In the region of 1058 and 1020 cm −1 , the bands for wE100 and AQAE shown can indicate the presence of phlorethols/fuhalols with ether bridges. This type of linkage, as well as the number and arrangement of phenolic hydroxyl groups in their structure, has a deep influence on the antioxidant properties in Laminariales species, as U. pinnatifida [ 33 ]. However, other ether linkages such as glycosidic bonds (also expected to be found in these extracts, given the presence of sulfate/sulfonic acid functional groups, e.g., in oligosaccharides) may also vibrate in this frequency.…”