Sequential high-pressure extraction of caffeine and bioactive compounds from caferana seeds (Bunchosia glandulifera)

Taguchi approach for assessing supercritical CO2 (sCO2) fluid extraction of polyhydroxyalkanoate (PHA) from Chlorella Vulgaris sp. microalgae

This research explicitly investigates the utilization of Chlorella Vulgaris sp. microalgae as a renewable source for lipid production, focusing on its application in bioplastic manufacturing. This study employed the supercritical fluid extraction technique employing supercritical CO2 (sCO2) as a green technology to selectively extract and produce PHA's precursor utilizing CO2 solvent as a cleaner solvent compared to conventional extraction method. The study assessed the effects of three extraction parameters, namely temperature (40-60 °C), pressure (15-35 MPa), and solvent flow rate (4-8 ml/min). The pressure, flowrate, and temperature were found to be the most significant parameters affecting the sCO2 extraction. Through Taguchi optimization, the optimal parameters were determined as 60 °C, 35 MPa, and 4 ml/min with the highest lipid yield of 46.74 wt%; above-average findings were reported. Furthermore, the pretreatment process involved significant effects such as crumpled and exhaustive structure, facilitating the efficient extraction of total lipids from the microalgae matrix. This study investigated the microstructure of microalgae biomatrix before and after extraction using scanning electron microscopy (SEM) and thermogravimetric analysis (TGA). Fourier-transform infrared spectroscopy (FTIR) was utilized to assess the potential of the extracted material as a precursor for biodegradable plastic production, with a focus on reduced heavy metal content through inductively coupled plasma-optical emission spectrometry (ICP-OES) analysis. The lipid extracted from Chlorella Vulgaris sp. microalgae was analysed using gas chromatography-mass spectrometry (GC-MS), identifying key constituents, including oleic acid (C18H34O2), n-Hexadecanoic acid (C16H32O2), and octadecanoic acid (C18H36O2), essential for polyhydroxyalkanoate (PHA) formation.

Caferana seeds (Bunchosia glandulifera) as a new source of nutrients: Evaluation of the proximal composition, solvent extraction, bioactive compounds, and δ-lactam isolation

•

Caferana seeds powder is a promising raw material for nutraceutical products.

•

There were found 9 essential amino acids and high levels of protein and carbohydrates.

•

10 compounds were identified in the volatile profile.

•

The lyophilized caferana seeds flour was subjected to solvent extraction.

•

Extracts contained phenolic compounds, caffeine, and δ-lactam.

The proximal composition, amino acid, carbohydrate, and volatile profiles of caferana (Bunchosia glandulifera) seeds flour were here assessed. Seeds were also subjected to the following extraction processes: one with pressurized ethanol (PLE) and two with ethanol + supercritical CO₂ mixture at different temperatures and pressures (SC1 and SC2). Extracts were characterized in terms of caffeine, total phenolic, and δ-lactam. The characterization of caferana seed and its extracts is unprecedented in terms of carbohydrate and volatiles profiles, besides the δ-lactam identification/isolation. SC2 extract exhibited a higher caffeine (9.3 mg/g) and δ-lactam (29.4 mg/g) content, whereas the PLE extract contained a higher total phenolic amount (3.0 mgGAE/g). Caferana is regionally associated to protective effects on mental health. Its byproduct (seed) revealed to be a promising source of bioactive compounds, and a potential raw material of nutritive extracts and flours that can be incorporated into pharmaceutical, nutraceutical, cosmetic, and food products.

Valorization of Tropical Biomass Waste by Supercritical Fluid Extraction Technology

The inception of sustainable and cleaner extraction technology has paved the way for the innovative development of nonconventional extractions, such as supercritical fluid extraction, apart from conventional extraction counterparts. The concept of biomass waste-to-wealth for the conversion of biomass waste or by-products into value-added products for diversified applications had piqued the prominent interest of researchers and industry players, especially with the abundance of biomass resources readily available in tropical regions that have yet to be tapped into to reach their full potential. In this paper, a critical review of the developments of supercritical fluid technology from its initial inception up to commercialized scalability, including its limitations, extraction of potential tropical biomass wastes for various types of applications, such as biopesticides, bio-repellents, phenolics, and lipids for biofuel, and its role in circular bioeconomy and sustainable development approaches, are discussed in detail.