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Macroalgae are known as abundant sources of phytochemicals, which offer a plethora of beneficial biological properties. Besides being the most notable classes of compounds found in macroalgae, phlorotannins, bromophenols, and terpenoids comprise some of the most relevant for their biological properties. Phlorotannins, mainly prevalent in brown algae and structurally characterized as complex polyphenolic compounds derived from phloroglucinol units, possess robust antioxidant, anti-inflammatory, antitumor, and cytotoxic activities, modulated by factors such as the degree of polymerization and environmental conditions. Bromophenols, halogenated compounds found in algae and other marine organisms, exhibit significant antioxidant and antiviral properties. Their diverse structures and bromination patterns contribute to their potential as therapeutic and chemical defense agents. Pigments (chemically described as primary terpenoids) play a critical role in light absorption and energy transfer in macroalgae and are divided into three main groups: (i) carotenoids, which are primarily found in brown algae and provide photoprotective and antioxidant benefits; (ii) chlorophylls, known for facilitating the conversion of light into biological energy; and (iii) phycobilins, which are mostly found in red algae and play important roles in light absorption and energy transfer, besides providing remarkable health benefits. Finally, secondary terpenoids, which are particularly abundant in red algae (e.g., the Rhodomelaceae family) are central to cellular interactions and exhibit significant antioxidant, antimicrobial, antidiabetic, and anti-inflammatory properties. This study represents a detailed analysis of the biosynthesis, structural diversity, and biological activities of these macroalgae metabolites, emphasizing their potential biological properties.

In recent years, consumers have been increasingly interested in natural, healthier, functional foods, with a focus on sea-based products such as algae. Bifurcaria bifurcata (BB) is a macroalga that belongs to the Phaeophyceae class. These brown algae are recognized as the source of bioactive molecules of great interest to the pharmaceutical and nutraceutical industries. The present work applied response surface methodology to optimize the microwave-assisted extraction of the poorly studied algae. The optimization variables were time, pressure, and solvent composition (ethanol/water) and the response parameters selected were yield, total phenolic and flavonoid content, and the antioxidant profile by evaluating DPPH•+, ABTS•+ scavenging activity, and β-carotene discoloration capacity. The results obtained reveal remarkable bioactivity of the crude extract of BB with positive results as an antioxidant and antimicrobial agent. Furthermore, the BB extract’s capacity to inhibit enzymes related to neurodegenerative diseases and its anti-inflammatory and anti-proliferation activity open the possibility of future food or pharmaceutical applications.

The excessive use of biocides has considerable environmental and economic impacts; this is why new technologies have been sought to decrease the concentration levels applied in an effort to reduce the use of these substances. Microencapsulation using cyclodextrins has been widely used in the food and pharmaceutical industries as a way of reducing the concentrations of the active substance necessary to achieve a biological effect and/or eliminate its irritating or toxicological effects. In this study, the inclusion complexation behavior and binding ability of benzothiazolinone (BIT) with different β-cyclodextrins (β-CD, HP-β-CD, and Me-β-CD) was investigated. The intermolecular interactions were examined through UV and FTIR spectroscopy, DSC, 1D 1H NMR, and 2D ROESY. The highest stability constant was observed for the BIT/Me-β-CD inclusion complex (299.5 ± 2.9 M−1). Antibacterial activity was investigated against Staphylococcus aureus and Escherichia coli, and the results revealed that the BIT/Me-β-CD inclusion complex displays a higher antibacterial activity than BIT. The acute toxicity of the biocide and inclusion complex was also examined using the photobacterium Aliivibrio fischeri. Although BIT exhibited higher toxicity than the inclusion complex, further investigation is needed due to the quorum quenching effect of β-CDs. The data found suggest that BIT microencapsulation can increase its aqueous solubility and can be used as an effective tool to improve its chemical, biological, and ecotoxicological properties.

Sargassum muticum (SM) poses a serious environmental issue since it is a fast-expanding invasive species occupying key areas of the European shoreline, disrupting the autochthonous algae species, and disturbing the ecosystem. This problem has concerned the general population and the scientific community. Nevertheless, as macroalgae are recognized as a source of bioactive molecules, the abundance of SM presents an opportunity as a raw material. In this work, response surface methodology (RSM) was applied as a tool for the optimization of the extraction of bioactive compounds from SM by microwave-assisted extraction (MAE). Five different parameters were used as target functions: yield, total phenolic content (TPC); and the antioxidant measurements of 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity (DPPH), 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS), and β-carotene bleaching (BC). After the optimal extraction conditions were determined (time = 14.00 min; pressure = 11.03 bar; ethanol = 33.31%), the chemical composition and bioactivity of the optimum extract was evaluated to appraise its antioxidant capability to scavenge reactive species and as a potential antibacterial, antidiabetic, antiproliferation, and neuroprotective agent. The results lead to the conclusion that MAE crude extract has bioactive properties, being especially active as an antiproliferation agent and as a nitric oxide and superoxide radical scavenger.

In recent years, the search for novel natural-based ingredients by food and related industries has sparked extensive research aimed at discovering new sources of functional molecules. Camellia japonica, traditionally known as an ornamental plant, has gained attention due to its diverse array of bioactive compounds with potential industrial applications. Although C. japonica flowers are edible, their phytochemical profile has not been thoroughly investigated. In this study, a phenolic profile screening through an HPLC–ESI-QQQ-MS/MS approach was applied to C. japonica flower extracts, revealing a total of 36 compounds, including anthocyanins, curcuminoids, dihydrochalcones, dihydroflavonols, flavonols, flavones, hydroxybenzoic acids, hydroxycinnamic acids, isoflavonoids, stilbenes, and tyrosols. Following extract profiling, their bioactivity was assessed by means of in vitro antioxidant, antimicrobial, cytotoxic, and neuroprotective activities. The results showed a multifaceted high correlation of phenolic compounds with all the tested bioactivities according to Pearson’s correlation analysis, unraveling the potential of C. japonica flowers as promising sources of nutraceuticals. Overall, these findings provide insight into the valorization of C. japonica flowers from different unexplored cultivars thus diversifying their industrial outcome.

Current food safety techniques and equipment are struggling to meet the evolving demands of the food industry [...]

Olive leaves are consumed as an extract or as a whole herbal powder with several potential therapeutic benefits attributed to polyphenols, tocopherol’s isomers, and flavonoids, among others. This study assessed the potential variance in the functional features presented by olive leaves from three different Portuguese cultivars—Cobrançosa, Madural, and Verdeal—randomly mix-cultivated in the geographical area of Vale de Salgueiros. Inorganic analysis determined their mineral profiles while an organic analysis measured their total phenolic and flavonoid content, and scanned their phenolic and tocopherol and fatty acid composition. The extracts’ biological activity was tested by determining their antimicrobial and antioxidant power as well as their ability to inhibit acetylcholinesterase, butyrylcholinesterase, MAO-A/B, and angiotensin-I-converting enzyme. The inorganic profiles showed them to be an inexpensive source able to address different mineral deficiencies. All cultivars appear to have potential for use as possible antioxidants and future alternative antibiotics against some multidrug-resistant microorganisms, with caution regarding the arsenic content in the Verdeal cultivar. Madural’s extract displayed properties to be considered a natural multitarget treatment for Alzheimer’s and Parkinson’s diseases, depression, and cardiometabolic and dual activity for blood pressure modulation. This work indicates that randomly cultivating different cultivars significantly modifies the leaves’ composition while keeping their multifaceted therapeutic value.

This review summarizes the recent findings on the development of different types of single and multitarget nanoparticles for disease detection and drug delivery to the brain, focusing on promising active principles encapsulated and nanoparticle surface modification and functionalization. Functionalized nanoparticles have emerged as promising tools for the diagnosis and treatment of brain disorders, offering a novel approach to addressing complex neurological challenges. They can act as drug delivery vehicles, transporting one or multiple therapeutic agents across the blood–brain barrier and precisely releasing them at the site of action. In diagnostics, functionalized nanoparticles can serve as highly sensitive contrast agents for imaging techniques such as magnetic resonance imaging and computed tomography scans. By attaching targeting ligands to the nanoparticles, they can selectively accumulate in the affected areas of the brain, enhancing the accuracy of disease detection. This enables early diagnosis and monitoring of conditions like Alzheimer’s or Parkinson’s diseases. While the field is still evolving, functionalized nanoparticles represent a promising path for advancing our ability to diagnose and treat brain disorders with greater precision, reduced invasiveness, and improved therapeutic outcomes.

Numerous photosynthetic organisms possess bioactive properties, with algae standing out for their distinctive characteristics that attract interest from diverse industries. For instance, the pharmaceutical industry has great interest in features like the neuroprotective, anti-glycemic and cytotoxic properties found in some algae species. Nonetheless, it is imperative to design efficient systems capable of releasing the bioactive compounds present in these extracts. In this regard, nanoparticles have attracted considerable attention across various fields, particularly in drug delivery applications. Lipid-based nanoparticles have emerged as a promising solution, offering numerous advantages. These nanoparticles exhibit high biocompatibility and biodegradability, making them suitable for use in biological systems. Additionally, they possess the ability to encapsulate both hydrophilic and hydrophobic drugs, thereby expanding their versatility. One remarkable attribute of lipid-based nanoparticles is their ability to cross the blood–brain barrier, a crucial physical barrier responsible for regulating the entry of chemicals into the brain and maintaining central nervous system homeostasis. Overcoming this barrier presents a significant challenge in the treatment of central nervous system disorders. Therefore, the objective of this study is to provide an overview of the latest advancements in the nanoencapsulation of natural extracts using lipid-based vesicular delivery systems.

The escalating global problem of antibiotic resistance among pathogenic microorganisms necessitates the exploration of effective alternatives to combat multi-resistance. Consumer demand for organic products has stimulated research on natural-origin matrices, such as plants, to develop antimicrobial additives. Camellia japonica flowers have demonstrated remarkable biological properties, making them a potential source of bioactive molecules for use as bio-preservatives. This study evaluated the antimicrobial activity of C. japonica flowers (var. Carolyn Tuttle) against food-related microorganisms using an agar diffusion assay. Extracts were obtained via a conventional and cost-effective maceration method (50 °C, 1 h) using 60% methanol as the solvent. The results revealed significant antimicrobial activity of C. japonica flowers (var. Carolyn Tuttle) against Staphylococcus aureus (10.29 mm), Pseudomonas aeruginosa (9.24 mm), and Salmonella enteritidis (6.95 mm). However, they did not exhibit activity against Escherichia coli, Staphylococcus epidermidis, and Bacillus cereus, unlike other varieties of C. japonica which displayed activity against these microorganisms. In conclusion, C. japonica flowers (var. Carolyn Tuttle) demonstrated potential as antimicrobial agents with promising applications in the food and pharmaceutical industries. This research contributes to developing natural and organic additives to combat antimicrobial resistance and meet consumer demands for safer and more sustainable products.

Macroalgae, or seaweed, has a long history of use in human diets, especially in Eastern nations. However, the present interest in these species is driven by their remarkable bioactive and nutritional qualities and their significant availability and underutilization, making them incredibly alluring to people following alternative dietary patterns like vegetarianism and veganism. Sargassum muticum, also known as Japanese wireweed or Asian seaweed, is considered edible and has been consumed in some cultures, popular as a soup ingredient in Korea. This brown macroalgae found in marine environments has been introduced in various regions outside its native range, including Europe and North America. Moreover, this species could be helpful in feeding animals or as soil fertilizer. In this study, the nutritional properties of this marine macroalga were investigated. Nutritional parameters such as protein, sugar, and fiber content were analyzed using classical techniques. In addition, its proximate composition was also determined in terms of moisture, fixed and volatile carbon, and ash content using thermogravimetry, and their major minerals, including calcium, potassium, and magnesium, was determined using the ICP-OS technique. In terms of its mineral content, it was found to have a high mineral content (21% of ash), which consisted mainly of calcium (9 g/kg dw), potassium (77 g/kg dw), and magnesium (12 g/kg dw). In addition, this study determined the presence of iodine using ICP-MS, and 106 mg/kg dw of this essential element was quantified in these algae. The results of this study highlighted the potential nutritional benefits of the tested marine algae. Their composition revealed significant concentrations of vital elements, making them highly advantageous for human/animal dietary requirements with possible health benefits.

Arnica montana L. (Asteraceae family) is a plant commonly used in traditional medicine, and several reports have characterized this plant’s bioactivities, especially its phenolic compounds. These compounds are well known for their numerous beneficial biological properties. Consequently, industry stakeholders from the feed, food, cosmetic, and pharmaceutical sectors are seeking extracts rich in phenolic compounds, which could be interesting for the development of bio-based applications. The objective of the present study was to characterize the phenolic profile of this species to lay the groundwork for further optimization studies to obtain the highest amount of phenolic compounds. Therefore, A. montana was extracted with an ethanol/water ratio of 80:20 (v/v) at room temperature for 1 h, and phenolic compounds were identified and quantified through UPLC (HPLC Dionex Ultimate 3000) with a mass detector (TSQ Quantis). In the extract, phenolics belonging to different groups were identified, namely eriodictyol-O-glucuronide (flavanone), hispidulin and luteolin (flavones), kaempferol and 6-methoxykaempferol, (flavonols), p-coumaric, feruloylquinic, caffeoylquinic, and dicaffeoylquinic isomers (hydroxycinnamic acids). However, only four of them could be quantified: kaempferol and the three hydroxycinnamic acids. The total phenolic content (mg/g of dry sample) was estimated to be 27.34 mg/g, with the most prevalent compounds being the dicaffeoylquinic acids (accounting for 79.5% of the total phenolics). It has been demonstrated that dicaffeoylquinic acids present anti-inflammatory and antioxidant activities, which have been linked to several beneficial effects. Thus, obtaining phenolic-rich extracts of A. montana may allow us to exploit this plant’s significant biological properties, and it could be a new ingredient for developing new applications in the nutraceutical, cosmetic, and/or pharmaceutical industries.

Food safety is one of the most contemporary subjects under the scope of the scientific community since it is a fundamental issue for the general population. The desire to use a simple, inexpensive, easy-to-read package freshness-indicator led to a multitude of proposals for package real-time sensors for food freshness indicators. The sensors’ design strategy is to target a physical or chemical modification that occurs by the spoiling process, such as changes in temperature, moisture, or the detection of foodborne pathogens. One of the most common approaches is evaluating changes in pH, since a significant amount of food spoilage occurs with significant alterations (e.g., acidity increases on dairy products). However, some safety concerns emerge from the use of complex artificial chemical molecules such as pH indicators in active labels/packages for food. Naturally occurring anthocyanins are a safe alternative to classic pH indicators and have been applied as sensitive molecules for pH changes aimed at the development of active labels and active packing for food. This proposal briefly reviews the latest scientific contributions on the application of anthocyanins in food spoilage sensors.

Seaweeds are photosynthetic organisms that have high contents of pigments. The coloration of each alga is defined by the content and combination of pigments synthesized, which varies among species and environmental conditions. The most abundant pigments in algae are chlorophylls and carotenoids, lipophilic molecules that can be used as natural colorants and have high acceptance by consumers. In this work, a simple and short hands-on time HPLC-DAD method for identifying and estimating the pigment content of algal extracts, specifically fucoxanthin, β-carotene and chlorophyll a was carried out. Using this optimized method, a pigment screening was performed on the ethanolic extracts obtained by ultrasound-assisted extraction from nine brown algal from the Atlantic coastline: Ascophyllum nodosum, Bifurcaria bifurcata, Fucus spiralis, Himanthalia elongata, Laminaria saccharina, Laminaria ochroleuca, Pelvetia canaliculata, Sargassum muticum and Undaria pinnatifida. HPLC results permitted to highlight L. saccharina and U. pinnatifida as promising sources of these three target pigments containing a total amount of 10.5 – 11.5 mg per gram of dry weight. Among them, the most abundant one was fucoxanthin, an added-value compound with a high potential to be commercially exploited by different industries, such as the food, cosmetic, and pharmaceutical sectors.

Fucoxanthin (Fx) has been proven to exert numerous biological properties, which makes it an interesting molecule with diverse industrial applications. In this study, the kinetic behavior of Fx was studied to optimize three variables: time (t—3 min to 7 days), temperature (T—5 to 85 °C), and concentration of ethanol in water (S—50 to 100%, v/v), in order to obtain the best Fx yield from Undaria pinnatifida using conventional heat extraction. The Fx content (Y1) was found through HPLC-DAD and expressed in µg Fx/g of algae sample dry weight (AS dw). Furthermore, extraction yield (Y2) was also found through dry weight analysis and was expressed in mg extract (E)/g AS dw. The purity of the extracts (Y3) was found and expressed in mg Fx/g E dw. The optimal conditions selected for Y1 were T = 45 °C, S = 70%, and t = 66 min, obtaining ~5.24 mg Fx/g AS; for Y2 were T = 65 °C, S = 60%, and t = ~10 min, obtaining ~450 mg E/g AS; and for Y3 were T = 45 °C, S = 70%, and t = 45 min, obtaining ~12.3 mg Fx/g E. In addition, for the selected optimums, a full screening of pigments was performed by HPLC-DAD, while phenolics and flavonoids were quantified by spectrophotometric techniques and several biological properties were evaluated (namely, antioxidant, antimicrobial, and cholinesterase inhibitory activity). These results could be of interest for future applications in the food, cosmetic, or pharmaceutical industries, as they show the Fx kinetic behavior and could help reduce costs associated with energy and solvent consumption while maximizing the extraction yields.

The antimicrobial activity of plants, algae, and derived extracts has been a subject of interest for the scientific community. Algae extracts have demonstrated their potential as a source of natural antimicrobial agents. Because of their antibacterial capacity and low toxicity, algae extracts have been studied as natural preservatives in food and cosmetic formulations. The use of these extracts has the potential to minimize the use of synthetic preservatives, which may be harmful to both human health and the environment. Nonetheless, the use of end-point techniques to calculate the minimal inhibitory concentration instead of creating growth inhibition curves usually leads to an absence of mathematical modeling procedures on the bacterial inhibition behavior of natural extracts. The goal of mathematical modeling is to describe the relationship between the concentration of an inhibitory agent (such as a drug or a toxin) and the growth rate of a population. For this purpose, the data obtained during the growth of six different bacteria in the presence of different concentrations of Ascophyllum nodosum (L.) extracts were recorded over 24 h. Later, the collected data were modeled based on different classical sigmoidal models, e.g., Weibull, logistic, and Gompertz, that were applied to define the critical growth phases and infer the kinetic parameters. The obtained parameters led to the conclusion that the inhibition mechanisms behind the antibacterial effects of the algae extracts are diverse towards different microorganisms. The presence of the extract led to a diminution of the specific growth velocity in some cases such as Staphylococcus epidermidis while in the replication of other bacteria such as Bacillus cereus, the extension of the lag phase was the predominant inhibition mechanism.

Hydroxymethylfurfural (HMF) is a naturally occurring compound that arises because of the thermal processing and storage of honey. The Codex Alimentarius Commission has established a threshold of 40 ppm as the upper limit for the HMF content in honey. This research aimed to investigate the impacts of varying heating temperatures (55, 65, and 75 °C) and heating times (10, 20, and 30 min), as well as storage temperatures (25 and 40 °C), over a period of three months. The study employed the response surface methodology (RSM) to evaluate the outcomes. The impacts of the variables mentioned above on the physicochemical properties, including the Lab color factors, pH, and moisture, were determined. Additionally, the concentration of HMF in the samples was analyzed. The prediction model of each treatment was computed. Analyses of the results obtained after the storage periods of 45 and 90 days were conducted. The findings indicated that pH, moisture content, and color were not significantly influenced by temperature, the duration of heat treatment, or the storage time. However, storage temperature considerably impacted both L* and a*. Furthermore, it was observed that all the variables significantly influenced the HMF content, and its concentration increased with the escalation of thermal processing and storage duration. Within the examined samples, the HMF content surpassed the standard limit in the model subjected to heating at 75 °C for 20 min and maintained at 40 °C for 90 days. In contrast, heating at 55 °C for 10 min, followed by storage at 25 °C for 45 days, produced the optimal HMF level.

Grapes are the third most produced fruit in the world, owing to their taste and use as raw materials for winemaking. Due to this fact, large volumes of waste biomass are generated as a result of grape juice and wine production, mainly grape seeds (GS) and peels. In recent decades, scientific research has highlighted the high content of polyphenols in GS, especially condensed tannins, and resveratrol. These compounds have been associated to various potential benefits to human health, such as antioxidant, hypoglycemic, hypolipidemic or anti-inflammatory bioactivities, among others. GS polyphenols may be incorporated into functional foods. Flour in wheat-based bakery products especially appears to be an attractive option. Two strategies may be followed. On one hand, the incorporation of GS flour increases the fiber, mineral, and protein content of bakery products, as well as their hardness and phenolic content. However, it seems that consumers may accept up to 10% of GS flour, since higher doses strongly diminish the organoleptic properties of the product. The other alternative involves the incorporation of polyphenol-rich GS extracts into bakery formulations, which would transfer their beneficial bioactivities to the final product. Nonetheless, this method is more laborious since it requires a prior chemical extraction of GS, and the control and addition of a safe, food-grade extract into the flour. Both strategies have been reported to increase the phenolic content and antioxidant capacity of bakery products. The direct incorporation of GS flour is affordable for industries, while the incorporation of polyphenol-rich extracts leads to the development of functional products with additional beneficial properties. This work discusses the benefits and potential hurdles of functional bakery products with incorporated GS flour and extracts, based on up-to-date evidence.

The antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARGs) are considered new classes of water contaminants due to their potential adverse effects on aquatic ecosystems and human health. This paper describes the susceptibility evaluation of Escherichia coli, isolated from the influent and effluent of the biological reactors in two wastewater treatment plants (WWTP1 and WWTP2), and the evaluation of the disinfection efficiency of the UV radiation system in WWTP2. The exposure to different families of antibiotics was evaluated, namely, macrolides (erythromycin, azithromycin, clarithromycin), quinolones (ofloxacin, ciprofloxacin), nitroimidazoles (metronidazole), sulfanilamides (sulfamethoxazole) and trimethoprim, the latter is used in combination with sulfamethoxazole due to its synergistic effect. The results of the antimicrobial susceptibility tests, using disc diffusion (Kirby–Bauer) method, showed the occurrence of E. coli strains resistance. The analysis performed indicated an overall resistance (considering both influents and effluents) in WWTP1 and WWTP2, of respectively: 33.3% and 37.5% to erythromycin; 0.0% and 4.0% to azithromycin; 25.0% and 29.2% to clarithromycin; 12.5% and 4.2% to ofloxacin; 16.7% and 4.2% to ciprofloxacin; 29.2% and 12.5% to trimethoprim; 41.7% and 12.5% to sulfamethoxazole. A variability of resistance was observed along the studied period, from WWTP1 and WWTP2, and from influent to effluent. Disinfection by UV demonstrated good performance, achieving in some samples 100% removal of E. coli that has growth in TBX agar. However, a proper supervision is needed in order to achieve the allowed limits concerning the number of bacteria. The results from this work contribute to a better awareness of ARB dissemination from wastewater treatment plants to the aquatic environment.

The production and consumption of shrimp species create massive amounts of shrimp bio-waste. In this study, shrimp shell waste from Palaemon serratus and Palaemon varians from the Portuguese coast was characterized. Regarding the antioxidant capacity, the obtained values were between 4.7 and 10.4 mg gallic acid equivalents (GAE)/g dry weight (dw) for Total phenolic content (TPC); 3 and 7 mg ascorbic acid equivalents (AAE)/g dw for Ferric reducing antioxidant power assay (FRAP); 0.4 and 1.2 mg Trolox equivalent (TE)/g dw for 2,2-diphenyl-1-picryl-hydrazyl-hydrate free radical scavenging (DPPH•); 4 and 11 mg TE/g dw for 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging activity (ABTS•+); and 72 and 130 mg TE/g dw for Oxygen radical absorbance capacity (ORAC). For the antimicrobial activity, shrimp shell waste from P. varians formed inhibition zones between 14 and 23 mm. Total carotenoid content values were in the range of 28 and 134 μg/g dw, and according to their HPLC-PAD profile, β-carotene and astaxanthin contents were between 0.3 and 7.6 μg/g dw and 1.1 and 26.1 μg/g dw, respectively. These studies are critical to recognizing the potential added value of shrimp shell waste as possible colorants and preservatives with antioxidant protection capacity to be used in the food industry.

Due to the increase in life expectancy, promoting active aging is a crucial challenge for the 21st century. Therefore, searching for new neuroprotective drugs is urgent, and marine macroalgae are considered excellent sources of structurally diverse bioactive molecules with recognized pharmaceutical and biomedical potential. Aiming to contribute to finding new neuroprotective drugs, a multi-step subcritical water extraction (SWE) process was applied to the green macroalga Codium tomentosum using a gradient of temperatures (from room temperature to 250 °C). Four fractions were obtained and fraction F4 (obtained in the range of 190–250 °C) was the most active against oxidative stress and enzymes linked to neurodegeneration and major depression. Therefore, phytosomes were prepared with F4 for a future food application. A Box–Behnken design with three independent variables was applied and the phytosomes prepared using the optimal conditions were further modified with DSPE-PEG (2000)-maleimide and APoE and characterized by dynamic light scattering (DLS), UV spectrophotometry, octanol–water partition coefficient (Kow), differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR). Results demonstrated that the complex was successfully formed and displayed low particle size and high octanol–water partition coefficient.

Brown macroalgae are a potential source of natural pigments. Among them, Undaria pinnatifida is recognized for its high concentration of fucoxanthin (Fx), which is a pigment with a wide range of bioactivities. In this study, three independent parameters were optimized for conventional heat extraction (CHE) to maximize the recovery of Fx from Undaria pinnatifida. Optimal conditions (temperature = 45 °C, solvent = 70%, and time = 61 min) extracted 5.1 mg Fx/g dw. Later, the bioactivities of the Fx-rich extracts (antioxidant, antimicrobial, and neuroprotective) were assessed using in vitro and in silico approaches. In vitro assays indicated that Fx has a strong antioxidant capacity and even stronger antimicrobial activity against gram-positive bacteria. This data was supported in silico where Fx established a high binding affinity to DR, a Staphylococcus aureus protein, through aa ALA-8, LEU-21, and other alkane interactions. Finally, the in vitro enzymatic inhibition of AChE using Fx, was further supported using docking models that displayed Fx as having a high affinity for aa TYR72 and THR 75; therefore, the Fx extraction behavior explored in this work may reduce the costs associated with energy and solvent consumption. Moreover, this paper demonstrates the efficiency of CHE when recovering high amounts of Fx from Undaria pinnatifida. Furthermore, these findings can be applied in different industries.

Brown algae are ubiquitously distributed in the NW coastline of the Iberian Peninsula, where they stand as an underexploited resource. In this study, five solvents were applied to the extraction of pigments from nine brown algae, followed by their determination and quantification by HPLC-DAD. A total of 13 compounds were detected: Six were identified as chlorophylls, six were classified as xanthophylls, and one compound was reported as a carotene. Fucoxanthin was reported in all extracts, which is the most prominent pigment of these algae. Among them, L. saccharina and U. pinnatifida present the highest concentration of fucoxanthin (4.5–4.7 mg∙g−1 dry weight). Ethanol and acetone were revealed as the most efficient solvents for the extraction of pigments, showing a maximal value of 11.9 mg of total pigments per gram of dry alga obtained from the ethanolic extracts of H. elongata, followed by the acetonic extracts of L. ochroleuca. Indeed, ethanol was also revealed as the most efficient solvent according to its high extraction yield along all species evaluated. Our results supply insights into the pigment composition of brown algae, opening new perspectives on their commercial exploitation by food, pharmaceutical, and cosmeceutical industries.

Algae are an underexploited source of natural bioactive compounds in Western countries, so an increasing interest in the valorization of these marine organisms has emerged in recent years. In this work, the effect of extracting solvent on the extraction yield, phenolic content, antioxidant capacity, and antimicrobial activity of nine brown macroalgae species (Ascophyllum nodosum, Himanthalia elongata, Undaria pinnatifida, Pelvetia canaliculata, Saccharina latissima, Bifurcaria bifurcata, Laminaria ochroleuca, Sargassum muticum, and Fucus spiralis) was assessed. Total phenolic content (TPC) and the antioxidant properties of extracts by different assays: radical scavenging activity (DPPH-RSA) and ferric reducing antioxidant power (FRAP) were performed. The antimicrobial activity of extracts was studied against six different foodborne microorganisms: Staphylococcus aureus, Staphylococcus epidermidis, Bacillus cereus, Escherichia coli, Salmonella enteritidis, and Pseudomonas aeruginosa. The highest extraction yield was achieved in ethanolic extracts. However, the highest TPC and FRAP values were obtained on the ethyl acetate extracts, especially from A. nodosum. Concerning algal species, the highest TPC and FRAP values were found in A. nodosum, while the highest DPPH-RSA values were achieved in the hexane extracts of B. bifurcata. The antimicrobial activity of algal extracts varied according to the solvent and alga selected, suggesting the species- and solvent-dependent behavior of this property, with B. bifurcata extracts showing the highest results for a wide range of bacteria. Our results provide insight on the characterization of widespread brown algae in the coasts of the North-Western region of the Iberian Peninsula, reflecting multiple health-enhancing properties which may lead to their exploitation in food, pharmacological, and cosmetic industries.

The search for food resources is a constant in human history. Nowadays, the search for natural and safe food supplies is of foremost importance. Accordingly, there is a renewed interest in eco-friendly and natural products for substitution of synthetic additives. In addition, microbial contamination of food products during their obtaining and distribution processes is still a sanitary issue, and an important target for the food industry is to avoid food contamination and its related foodborne illnesses. These diseases are fundamentally caused by certain microorganisms listed in this review and classified according to their Gram negative or positive character. Algae have proven to possess high nutritional value and a wide variety of biological properties due to their content in active compounds. Among these capabilities, macroalgae are recognized for having antimicrobial properties. Thus, the present paper revises the actual knowledge of microbial contaminants in the food industry and proposes antimicrobial algal compounds against those pathogenic bacteria responsible for food contamination as valuable molecules for its growth inhibition. The capacity of algae extracts to inhibit some major food pathogen growth was assessed. Moreover, the main applications of these compounds in the food industry were discussed while considering their favorable effects in terms of food safety and quality control.

In the last few decades, attention on new natural antimicrobial compounds has arisen due to a change in consumer preferences and the increase in the number of resistant microorganisms. Macroalgae play a special role in the pursuit of new active molecules as they have been traditionally consumed and are known for their chemical and nutritional composition and their biological properties, including antimicrobial activity. Among the bioactive molecules of algae, proteins and peptides, polysaccharides, polyphenols, polyunsaturated fatty acids and pigments can be highlighted. However, for the complete obtaining and incorporation of these molecules, it is essential to achieve easy, profitable and sustainable recovery of these compounds. For this purpose, novel liquid–liquid and solid–liquid extraction techniques have been studied, such as supercritical, ultrasound, microwave, enzymatic, high pressure, accelerated solvent and intensity pulsed electric fields extraction techniques. Moreover, different applications have been proposed for these compounds, such as preservatives in the food or cosmetic industries, as antibiotics in the pharmaceutical industry, as antibiofilm, antifouling, coating in active packaging, prebiotics or in nanoparticles. This review presents the main antimicrobial potential of macroalgae, their specific bioactive compounds and novel green extraction technologies to efficiently extract them, with emphasis on the antibacterial and antifungal data and their applications.