Abstract
The present work aimed at studying Saccorhiza polyschides extracts obtained by subcritical water extraction as a potential source of essential macro and trace elements, aiming for its potential application as a biofertilizer. The mineral composition, as well as sulfate, chlorine and iodine, total organic matter, and total nitrogen content, were determined on the extracts obtained from seaweeds harvested during low tide at the northern Portuguese coast. The selected parameters are important for a biofertilizer. Among the macronutrients, the most abundant was K (15.7 ± 0.2 g/L), followed by Na (5.46 ± 0.11 g/L), S (1.52 ± 0.06 g/L), Ca (1.09 ± 0.11 g/L), and Mg (1.02 ± 0.08 g/L). Several important micronutrients (Zn, B, Cl, P, Mo, V, Se, and I) have also been found in the extracts. The total organic matter was 34.1 ± 0.3 g/L. The extracts present low levels of toxic compounds such as Ni, Cd, and Pb. Considering the composition of the obtained extracts, these can find application in the development of fertilization products. The composition of subcritical water extracts of S. polyschides suggests that they may have important characteristics as a biofertilizer and can be an option in biofortification experiments with essential nutrients. The method can be easily scaled up which makes it attractive for agricultural applications.
Highlights
Seaweeds are currently used in many coastal countries as human food, in animal feed formulation, and as fertilizer in agriculture [1,2,3].The use of seaweeds as plants’ source of organic matter and nutrients is related to earlier seed germination, improved crop performance and yield, increased resistance to biotic and abiotic stress, and enhanced postharvest shelf-life of perishable products [4,5,6]
This work aimed at the application of Subcritical water extraction (SWE) to prepare S. polyschides extracts and the study of its composition regarding the macro and microminerals, total organic matter, nitrogen, sulfur, chloride, and iodine concentrations in order to assess its potential application as a biofertilizer
According to the criteria proposed by Arnon and Stout [39,40], plant nutrients can be classified taking into account their importance and quantities necessary to plants as main macronutrients: N, P, K, secondary macronutrients: Ca, Mg, S, micronutrients: Fe, Mn, Zn, Cu, Ni, B, Mo, Cl, beneficial minerals: Na, Si, Co, Al, V, Ni, Se, As, F, Br, I, Cd, Cr, Pb, and potentially toxic elements: Cd, Cr, Pb, Hg, Ni, Se, As
Summary
The use of seaweeds as plants’ source of organic matter and nutrients is related to earlier seed germination, improved crop performance and yield, increased resistance to biotic and abiotic stress, and enhanced postharvest shelf-life of perishable products [4,5,6]. Seaweeds can be either directly applied in the soil or used as compost to improve soil fertility and the productivity of crops [2,4,7], but potential negative impacts related to salinity, sand, and heavy metal content must be taken into account [8]. A potentially advantageous alternative is the use of seaweed extracts as fertilizers [4,5,9]. The mechanism by which these extracts affect cellular metabolism of plants is based in the presence of macro and micronutrients, amino acids, vitamins, and other substances, including an eventual synergistic action of the different components [3,11]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
