Journal of Applied Phycology最新文献

Ultrasound-assisted extraction and enzyme-assisted extraction are two methods that can be employed to recover valuable compounds from seaweeds at milder operating conditions than conventional chemical extraction methods. The aim of the study was to determine whether pH, enzyme addition and extraction temperature significantly impacted extraction of alginate from Ecklonia maxima in the presence of ultrasonication and to model extraction kinetics. Firstly, a 2³ factorial experimental design was employed at constant sonication rate, with pH (8 and 10), temperature (50 and 60 °C), and enzyme-to-substrate ratio (E:S 0 and 1 %) as the independent variables. Secondly, extraction kinetics of alginate were investigated at different extraction conditions, through fitting of the Peleg and Power models. Highest extraction for alginate was achieved at pH 10, 60 °C, E:S = 0 % within the first 60 min of extraction. The addition of enzyme improved solubilised dry matter content, but it had a less clear impact on the alginate yield. Both the Peleg (R² = 0.893 – 0.997) and Power function (R² = 0.861 – 0.987) models provided good fit to the experimental data and can used to describe extraction kinetics of alginate during combined ultrasound-enzymatic assisted extraction.

The traditional and local edible brown algae Ecklonia cava subspp. kurome (EK) and stolonifera (ES) are rich in minerals, phlorotannins (brown algal polyphenols), and water-soluble dietary fibres (alginate, laminaran, and fucoidans). These dried powders increase not only alginate- and laminaran-degrading Bacteroides acidifaciens- and B. intestinalis-like bacteria but also Faecalibaculum. To elucidate the effect of EK and ES ingredients, other than dietary fibres, on gut microbiota, 100 mL of ethanolic/aqueous extract solutions (EK-S, ES-S; final solvent was distilled water) were prepared from 100 g of dried samples. EK-S and ES-S contained total phenolic contents of 160 and 120 μmol phloroglucinol equivalent mL^-1, respectively. A diet containing 5% (v/w) EK-S or ES-S was fed to ICR mice for 14 days. Amplicon sequencing of the 16S rDNA (V4) gene revealed that EK-S and ES-S increased Faecalibaculum abundance 2-fold and more, and this was the predominant genus (37–38%) in mice. However, the abundances of B. acidifaciens- and B. intestinalis-like bacteria did not increase. Akkermansia muciniphila-like bacteria were higher in EK-S-fed mice. Faecalibaculum and Akkermansia are regarded as desirable gut commensals correlated with anti-inflammatory and immunomodulatory effects on the host’s health. These results suggest that phlorotannins have beneficial functional effects on indigenous gut bacteria responsible for host health.

This methodology paper introduces an illuminated culture flask-based 3D-printed bioreactor system (FlaskLED) based on Arduino, Grove ecosystem and LED sticks. The Arduino microcontroller allows extensibility and future upgrades via programming and other modifications. We provide the 3D printer files, video presentation of assembly instructions and a detailed description of the INO code and wiring scheme. The INO code presented can be used to produce different light colors and patterns of varying intensity and durations (intermittent/flashing/pulsing light). The system was validated by examining the toxicity of Au³⁺ ions on Phaeodactylum tricornutum growth. The capabilities of the system offer unique applications for laboratory and industrial research. Our aim is to provide a low-cost and open-source tool to promote and improve cultivation of microalgae and other photosynthetic organisms under different laboratory and experimental setups.

The deficiency in the worldwide protein provision from marine capture fisheries has led the Malaysian government to reevaluate its aquaculture approach, prioritising three commodities: seaweed, fish, and marine shrimp. However, comprehensive documentation of the performance of the Malaysian aquaculture sector, particularly in seaweed production, is lacking. Caulerpa (Chlorophyta), a seaweed genus abundantly available in Malaysia, holds the potential to emerge as a primary alternative food source in the future. This paper offers an overview of Caulerpa aquaculture, specifically focusing on C. lentillifera and C. racemosa, covering aspects such as taxonomy, phytomorphology, geographical distribution and habitat, cultivation system, chemical composition, pharmacological properties, and future prospects for sustainable aquaculture. Although the cultivation system has been implemented on a small scale in various districts in Malaysia, it is anticipated to escalate production and productivity due to the substantial demand for Caulerpa spp. both domestically and globally. The cultivation of Caulerpa spp. in Malaysia, in alignment with the National Agrofood Policy 2021–2030 (NAP 2.0), signals a trajectory toward enhancing the nation's food security in aquaculture and meeting the economic requirements for seaweed production.