Microalgae-derived bioactive compounds: metabolic potential, extraction strategies, and sustainable applications in food, pharmaceuticals, and animal feed

Extraction of functional and bioactive compounds with high volumes, quality, and bioactivity to improve their delivery particularly in food applications has always been a priority in food chemistry. The continuous search for newer, more sophisticated extraction mediums with improved sustainability, extractability, stability, bioactivity, and safety has resulted in the development of deep eutectic solvent (DES) based on the eutectic behavior of various salts. DESs are the mixtures of hydrogen bond donor (HBD) and hydrogen bond acceptor (HBA) with complexing agents having safe biological backgrounds and a promising approach for current innovations in green extraction technologies. Research efforts focused on their utilization as economic extraction mediums with relatively higher environmental and health safety have been growing fast. Significant publication count on DES for various food and pharmaceutical applications to overcome the limitations of conventional solvents has been reported in the last decade. Although, limited work has been carried out on the extraction of bioactive compounds from various biological sources yet the persuasive recognition of these extraction systems has fascinated the consideration of the research community for their investigation. This review focuses primarily on addressing the distinctive qualities of DES especially as extraction medium along with the conventional and neoteric extraction techniques for a wide range of bioactive compounds. The review summarizes the-state-of-the-art application of DESs in the extraction of bioactive compounds their classification, preparation, activity, safety concerns, recent trends, and future perspectives for their potential utilization in the food industry. Novelty impact statement DES is new generation solvents and based on the material from which they are derived they can be the safest, cheapest, and most effective extraction systems. Extraction efficiency and recycling of both the bioactive compounds and the solvent are significantly improved by using DES. Overall, the extractability, safety, cytotoxicity and ecotoxicity of the novel DESs need extensive research trials and clinical documentation.

Marine biorefinery: an environmentally sustainable solution to turn marine biomass and processing wastes into value-added products and profits

Ulva spp., commonly known as sea lettuce, are versatile green macroalgae that offer strong potential for integration into emerging blue and circular bioeconomies. Ulva is a fast-growing and nutrient-tolerant species that produces renewable biomass rich in bioactive compounds with economic potential. This review summarizes advances in the characterization, extraction, and industrial utilization of Ulva biomass, highlighting opportunities for scalable biorefinery approaches. Key bioactive classes include sulfated polysaccharides (ulvans), proteins and peptides, polyunsaturated fatty acids, pigments, and phenolic compounds, which exhibit diverse antioxidant, antimicrobial, and anti-inflammatory properties. Recent developments in green extraction technologies, such as ultrasound-, microwave-, and enzyme-assisted methods, as well as supercritical fluids and deep eutectic solvents, have improved yields in processing Ulva biomass while reducing environmental impact. Beyond laboratory studies, industrial applications are expanding across the food, cosmetic, pharmaceutical, and biomaterial sectors, supported by growing interest in sustainable marine ingredients. However, challenges remain in biomass standardization, taxonomy, large-scale cultivation, and regulatory approval. Integrating Ulva within a circular bioeconomy requires harmonized methodologies and life-cycle assessments to ensure economic and environmental sustainability. Ulva spp. combine rapid growth, carbon capture, and a unique spectrum of bioactive compounds, making them a versatile and scalable marine feedstock for sustainable, circular biorefineries across food, health, and material applications.

Garden cress oil as a vegan source of PUFA: Achieving through optimized supercritical carbon dioxide extraction

Bergamot (Citrus bergamia Risso et Poiteau), a citrus fruit typically cultivated in the Mediterranean basin, represents a valuable source of bioactive compounds, including polyphenols, flavanone glycosides, and essential oil constituents, which are associated with antioxidant and metabolic effects. Notably, these compounds are highly concentrated not only in the edible fraction but also in industrial by-products, such as peel and pomace, which represent an underexploited resource for sustainable valorisation. This review examines recent advances (2020–2025) in the recovery and application of bioactive compounds from bergamot by-products (BBP), with a focus on green extraction technologies, including ultrasound- and microwave-assisted extraction, enzyme-assisted processes, supercritical fluids, and natural deep eutectic solvents. Particular attention is given to the incorporation of BBP-derived extracts into food systems as natural antioxidants, flavouring agents, and functional ingredients. In addition, current evidence on their nutritional relevance and biological activities, including antioxidants, anti-inflammatory, and lipid-lowering effects, is critically discussed. The integration of green extraction technologies with stabilization strategies, such as microencapsulation, supports the development of clean-label foods enriched with bergamot bioactives, contributing to both product functionality and sustainability. Overall, bergamot by-products (BBP) emerged as a promising model for the circular recovery of natural bioactive compounds and their incorporation into innovative functional food formulations.

BACKGROUNDMarine‐derived omega‐3 polyunsaturated fatty acids (PUFA) are used globally as food supplements for their anti‐inflammatory properties and to reduce the risk of obesity, cardiovascular diseases, and cancer. New Zealand green‐lipped mussels (Perna canaliculus) contain diverse valuable compounds, including omega‐3 PUFA. The most abundant omega‐3 PUFA in Perna canaliculus are eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), both of which account for many of the health benefits accredited to these mussels. This research investigates the feasibility of using deep eutectic solvents (DESs) to isolate EPA and DHA from Perna canaliculus.RESULTSTwenty‐two hydrophobic DESs were screened using COSMO‐RS software to predict their affinity for EPA and DHA. Nine top‐ranked DESs were used for experimental extraction validation. The results exposed that the extraction capacity of the menthol: lidocaine DES (1:1 M ratio) for EPA and DHA was superior (172.04 μg EPA g−1 dry weight (DW) of biomass and 602.79 μg DHA g−1 DW) amongst other DESs. This was a considerably higher extraction yield than that observed using ethanol (95.65 μg EPA g−1 DW and 311.49 μg DHA g−1 DW). The optimisation of the menthol: lidocaine ratio identified a 1:2 M ratio as the optimal composition for this DES. The highest yields of EPA (267.59 μg g−1 DW) and DHA (1014.84 μg g−1 DW) were obtained by this optimised DES ratio at optimum extraction conditions (extraction temperature 65 °C, extraction time 2.12 h, and biomass loading 5 w/v%). The EPA and DHA showed good stability in the menthol: lidocaine DES over 7 days. This DES also showed good reusability, with a comparable extraction efficiency being observed after five extraction cycles.CONCLUSIONThis research revealed that menthol‐based DES can be a potential green solvent for the extraction of EPA and DHA from New Zealand green‐lipped mussels and it may be applicable for extracting other bioactive compounds with similar characteristics. © 2023 The Authors. Journal of Chemical Technology and Biotechnology published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry (SCI).

IFST Winning Articles

The global citrus-processing industry generates 15–32 million tonnes of waste annually. Lemon-processing residues—peels, seeds, and pomace—constitute 45–55% of fruit mass and harbour high-value bioactive compounds amenable to cascade valorisation. This review (Part I of a two-part series) examines green extraction technologies for recovering bioactive compounds from lemon waste streams. Following bibliometric analysis of 847 publications (2003–2025), this work delineates the compositional heterogeneity of lemon fractions and establishes a hierarchical framework for value-added products encompassing essential oils, pectin, polyphenols, seed oils, citric acid, industrial enzymes, α-cellulose, and nanocrystalline cellulose. Four sustainable extraction methodologies are systematically evaluated: ultrasound-assisted extraction, microwave-assisted extraction, supercritical CO2 extraction, and enzyme-assisted extraction. Comparative assessment demonstrates yield improvements of 16–112% over conventional approaches, processing-time reductions of 89–98%, and energy savings up to 95%. Critical research gaps include fragmented single-product valorisation, insufficient techno-economic assessment, and limited industrial-scale validation. Integrated cascade biorefineries employing sequential green extraction protocols offer economically viable pathways for transforming lemon waste into diversified revenue streams. Industrial implementation, circular-economy integration, and techno-economic feasibility are addressed in Part II.

Extraction of bioactive compounds from Lion's Mane mushroom by-product using supercritical CO2 extraction

Multiple promoters driving the expression of astaxanthin biosynthesis genes can enhance free-form astaxanthin production

Goji berries (Lycium barbarum L.), a superfruit with a long history of usage in Asian medicine, are gaining recognition for their potential as functional foods because of their high levels of antioxidants, flavonoids, anthocyanins, and phenolic acids. With the growing demand from consumers for clean‐label and naturally sourced ingredients, environmentally friendly extraction technologies are now crucial to creating bioactive‐rich extracts appropriate for food and nutraceutical applications. Three eco‐friendly extraction methods—pressurized water extraction (PWE), microwave‐assisted extraction (MAE), and ultrasound‐assisted extraction (UAE)—are thoroughly evaluated in this study to maximize the bioactive compounds’ recovery from Goji berry fruits. Water was the only solvent used in all extraction processes, guaranteeing environmental sustainability and food‐grade compliance. The solid/liquid ratio, temperature, duration, pressure, and power were all optimized using response surface methodology (RSM). The total phenolic content (TPC), total flavonoid content (TFC), total anthocyanin content (TAC), and antioxidant activity (DPPH inhibition) of the extracted materials were assessed. Under ideal circumstances, the extracts’ rutin contents were ascertained by HPLC analysis. According to the findings, MAE had the highest DPPH inhibition rate (75.942%), whereas PWE had the most TPC (17.753 mg GAE/g extract). The flavonoid content of both techniques was comparable. The UAE produced the best energy‐to‐bioactivity ratio and the most anthocyanin‐rich extracts (3.607 mg C3G/g). UAE is the most ecologically friendly option among the techniques, as evidenced by its highest overall efficiency in terms of bioactive recovery and antioxidant capacity. This is the first study to employ a combined approach of RSM and bioactivity‐energy efficiency assessment to optimize and compare water‐based PWE, MAE, and UAE methods for Goji berries. These results demonstrate that green extraction technologies can be leveraged to sustainably produce bioactive compounds from functional foods like Goji berries, which have significant applications in food, nutraceuticals, and cosmetics.

A marine habitat including microalgae and macroalgae is considered as a rich and underexploited source of bioactive compounds. This chapter discusses different techniques used to efficiently extract bioactive compounds present in microalgae. Due to the huge biodiversity of algae, discussion is limited and we have tried to give an overview of technologies being used to extract valuable compounds from algae, their use in food and therapeutic applications and their market applications for better development in the future. Due to the low yield of bioactive compounds with less selectivity achieved by conventional methods, novel techniques have been developed for the extraction of platform molecules such as polyunsaturated fatty acids, lipids, carotenoids, proteins, carbohydrates, vitamins, minerals, polyphenols and many more from algal biomass. New extraction techniques which have been successfully used to extract biologically active compounds are supercritical fluid extraction, pressurized fluid extraction, microwave-assisted extraction, ultrasound-assisted extraction and enzyme-assisted extractions, which are also used in the food and pharmaceutical industries.

Natural sources of bioactive compounds: recent advances in isolation, functionalization, and health benefits.

Supercritical CO2 and subcritical water extraction of Curcuma longa bioactive compounds

Bioactive compounds derived from microalgae have garnered considerable attention as valuable resources for drugs, functional foods, and cosmetics. Among these compounds, photosynthetic pigments and polyunsaturated fatty acids (PUFAs) have gained increasing interest due to their numerous beneficial properties, including anti-oxidant, anti-viral, anti-bacterial, anti-fungal, anti-inflammatory, and anti-tumor effects. Several microalgae species have been identified as rich sources of bioactive compounds, including the Chlorophyceae Dunaliella and Haematococcus, the Bacillariophyta Phaeodactylum and Nitzschia, and the dinoflagellate Crypthecodinium cohnii. However, most of the reported microalgae species primarily grow through autotrophic mechanisms, resulting in low yields and high production costs of bioactive compounds. Consequently, the utilization of heterotrophic microalgae, such as Chromochloris zofingiensis and Nitzschia laevis, has shown significant advantages in the production of astaxanthin and eicosapentaenoic acid (EPA), respectively. These heterotrophic microalgae exhibit superior capabilities in synthesizing target compounds. This comprehensive review provides a thorough examination of the heterotrophic production of bioactive compounds by microalgae. It covers key aspects, including the metabolic pathways involved, the impact of cultivation conditions, and the practical applications of these compounds. The review discusses how heterotrophic cultivation strategies can be optimized to enhance bioactive compound yields, shedding light on the potential of microalgae as a valuable resource for high-value product development.