Space-Efficient 3D Microalgae Farming with Optimized Resource Utilization for Regenerative Food.

Photosynthetic microalgae produce valuable metabolites and are a source of sustainable food that supports life without compromising arable land. However, the light self-shading, excessive water supply, and insufficient space utilization in microalgae farming have limited its potential in the inland areas most in need of regenerative food solutions. Herein, this work develops a 3D polysaccharide-based hydrogel scaffold for vertically farming microalgae without needing liquid media. This liquid-free strategy is compatible with diverse microalgal species and enables the design of living microalgal frameworks with customizable architectures that enhance light and water utilization. This approach significantly increases microalgae yield per unit water consumption, with an 8.8-fold increase compared to traditional methods. Furthermore, the dehydrated hydrogels demonstrate a reduced size and weight (≈70% reduction), but readily recover their vitality upon rehydration. Importantly, valuable natural products can be produced in this system including proteins, carbohydrates, lipids, and carotenoids. This study streamlines microalgae regenerative farming for low-carbon biomanufacturing by minimizing light self-shading, relieving water supply, and reducing physical footprints, and democratizing access to efficient aquatic food production.

Hybrid lignin particles via ion-crosslinked for selective removal of anionic dyes from water.

Hybrid lignin (HL) particles were synthesized by compounding lignosulfonate and carboxylated chitosan through a simple ionic cross-linking method, and modifying by polyvinylpolyamine. Due to the synergistic effect of recombination and modification, the material exhibits excellent adsorption performance for anionic dyes in water. The structural characteristics and adsorptive behavior were systematically investigated. The pseudo-second-order kinetic model and the Langmuir model were revealed to well describe the sorption procedure of HL for anionic dyes. The results exhibited that the sorption capacities of HL on sodium indigo disulfonate and tartrazine were 1099.01 mg/g and 436.68 mg/g, respectively. Simultaneously, the adsorbent behaved no significant adsorption capacity loss after five adsorption-desorption cycles, indicating its superb stability and recyclability. Additionally, the HL exhibited excellent selective adsorption of anionic dyes form binary dye adsorption systems. The interaction forces between adsorbent and dye molecules, such as hydrogen bonding, π-π stacking, electrostatic attraction and cation bonding bridge, are discussed in detail. The facile preparation process and superior dyes removal performance of HL were considered a potential adsorbent to remove anionic dyes from wastewater.

Construction of ratiometric fluorescence MIPs probe for selective detection of tetracycline based on passion fruit peel carbon dots and europium.

A new type of ratiometric molecularly imprinted fluorescence probe (B-CQDs@Eu/MIPs) based on biomass carbon quantum dots (B-CQDs) and europium ions (Eu3+) has been prepared to recognize and detect tetracycline (TC). In the experiment, the fluorescent material B-CQDs were prepared using passion fruit peels through microwave-assisted method, which by the meantime achieves the reuse of biomass waste. TC can block the transition of some parts of electrons in the prepared B-CQDs from the excited state to the ground state, resulting in the weakening of its blue light (Ex = 394 nm, Em = 457 nm), while TC can be chelated by Eu3+ and emit red characteristic fluorescence (Ex = 394 nm, Em = 620 nm) due to the antenna effect. Thus, a ratiometric fluorescence response to TC is the result of the combined B-CQD and Eu3+ . Based on this, we established the ratiometric fluorescent molecularly imprinted (MIP) probe for the detection of TC. The prepared B-CQDs@Eu/MIPs is aimed at catching the fluorescence changes of target tetracycline (TC) sensitively with the special combination of the specific recognition cavities and TC. The linear fluorescence quenching range of TC in milk using the fluorescent probe was 25-2000 nM, and the detection limit was 7.9 nM. The recoveries of this method for TC were 94.2-103.7%, and the relative standard deviations (RSDs) were 1.5-5.3%. Owing to the predetermined nature of MIP technology and the special response of ratio fluorescence, the interference of common substances is eliminated completely, which greatly improved the selectivity of its practical applications.