Seaweeds and their derived products have long been valued in organic agriculture, serving roles in biofertilizers, biostimulants, and soil conditioners due to their rich content of bioactive compounds. With increasing concerns over the negative impacts of synthetic agrochemicals on food security and environmental health, seaweeds offer a sustainable alternative for improving soil fertility and crop productivity. This review synthesizes recent findings on the use of seaweeds to enhance soil physicochemical properties, stimulate beneficial microbial activity, and improve nutrient availability. Furthermore, it highlights how seaweed applications can mitigate various abiotic stresses, such as droughts, salinity, and nutrient deficiency, by enhancing antioxidant defenses and promoting physiological and biochemical resilience in plants. Key agronomic benefits include improved seed germination, root development, photosynthesis, biomass accumulation, and yield performance. By acting as natural soil amendments, seaweeds support sustainable soil management and contribute to long-term agricultural resilience. This review emphasizes the urgent need for standardized application strategies and integrated research to unlock the full potential of seaweed-based solutions in sustainable farming systems.

Recently, a trend can be observed to replace plant protection chemicals in nursery production by products of natural origin. Such products increase plants’ resistance to stressful conditions and lower their susceptibility to pathogens. They may also offer an alternative to chemicals stimulating rhizogenesis. The aim of this work was to evaluate the effects of foliar applications of AlgaminoPlant, a biostimulator based on a seaweed extract, relative to auxin-containing preparations, on root growth in stem cuttings of common ninebark (Physocarpus opulifolius). Cuttings were sprayed with water solution of IBA or AlgaminoPlant once, twice or three times during the rooting period at one week intervals and powder IBA was also applied directly to the bases of cuttings. The best rooting was observed after powder IBA application and satisfactory results were observed for AlgaminoPlant and aqueous IBA solution. Treatments with AlgaminoPlant and IBA increased photosynthetic efficiency, chlorophyll contents, total soluble sugars, soluble proteins, indole derivatives and catalase activity while the hydrogen peroxide level and peroxidase activity were reduced. The effects of AlgaminoPlant on rhizogenesis were comparable to synthetic IBA, or only slightly lower. Hence, if needed, synthetic auxin IBA may be replaced by AlgaminoPlant which is considered an environmentally friendly product.

The use of natural biostimulants is becoming an attractive option in order to reduce the use of fertilizer and increase the yield of crops. In particular, algal extracts are suitable candidates as they positively affect plant physiology. Among crops, lettuce often requires the use of biostimulants to improve both the quality and quantity of production. The aim of this work is to investigate the potential use of a Scenedesmus quadricauda extract as a biostimulant in order to obtain sustainable cultivation and a reduction in the cost of chemical fertilizers in lettuce cultivation. Therefore, the effect of S. quadricauda extract on lettuce seedlings was explored by evaluating the physiological parameters, chlorophyll, carotenoid, and total protein contents as well as several plant enzymatic activities involved in primary and secondary metabolisms. The experiment was performed by growing plants on inert substrate (pumice) with a 16-h photoperiod, by carrying out two consecutive radical treatments, one week apart, using a concentration of the extract corresponding to 1 mg Corg L−1. Lettuce plants were sampled at 1, 4, and 7 days from the first treatment and 7 days from the second treatment. The results showed that the S. quadricauda extract positively affected the growth of lettuce seedlings, mainly acting at the shoot level, determining an increase in dry matter, chlorophylls, carotenoids, proteins, and influencing the activities of several enzymes involved in the primary metabolism.

The use of seaweed-based bioproducts has been gaining momentum in crop production systems owing to their unique bioactive components and effects. They have phytostimulatory properties that result in increased plant growth and yield parameters in several important crop plants. They have phytoelicitor activity as their components evoke defense responses in plants that contribute to resistance to several pests, diseases, and abiotic stresses including drought, salinity, and cold. This is often linked to the upregulation of important defense-related genes and pathways in the plant system, priming the plant defenses against future attacks. They also evoke phytohormonal responses due to their specific components and interaction with plant growth regulation. Treatment by seaweed extracts and products also causes significant changes in the microbiome components of soil and plant in support of sustainable plant growth. Seaweed extracts contain a plethora of substances which are mostly organic, but trace levels of inorganic nutrient elements are also present. Fractionation of seaweed extracts into their components and their respective bioassays, however, has not yielded favorable growth effects. Only the whole seaweed extracts have been consistently proven to be very effective, which highlights the role of multiple components and their complex interactive effects on plant growth processes. Since seaweed extracts are highly organic, they are ideally suited for organic farming and environmentally sensitive crop production. They are also very compatible with other crop inputs, paving the way for an integrated management approach geared towards sustainability. The current review discusses the growth and functional effects evoked by seaweed extracts and their modes and mechanisms of action in crop plants which are responsible for elicitor and phytostimulatory activities. The review further analyses the potential value of seaweed extracts in integrated crop management systems towards sustainable crop production.

Seaweeds are abundant and valuable marine resources that contain a diverse range of bioactive compounds, including lipids, minerals, phytohormones, amino acids, carbohydrates, osmo-protectants, and antibacterial substances. Historically, seaweeds have been widely used in food, feed, and medicine, but their agricultural significance has gained increasing recognition in recent years. With the growing shift toward organic and sustainable farming, seaweed extracts (SEs) have been explored as biofertilizers, soil conditioners, and natural biocontrol agents. They play a crucial role in enhancing soil health, improving plant growth, and increasing resistance against pests, diseases, and abiotic stressors such as drought, salinity, and extreme temperatures. Their ability to stimulate plant defense mechanisms and promote root development makes them an eco-friendly alternative to synthetic agrochemicals. Numerous studies have demonstrated the efficacy of seaweed extracts in boosting crop productivity while minimizing environmental impact. This review highlights recent advancements in seaweed-based agricultural applications, focusing on their benefits, mechanisms of action, and potential for integration into sustainable farming practices.

It is unclear whether different processing methods change the biological functions of foods and how these functions are evaluated in the human body. Here, steamed bread and baked bread, the traditional staple foods in China and many Western countries, were made by steaming and baking, respectively, using one piece of fermented wheat dough and then consumed by 16 healthy young volunteers. By detecting 38 cytokines, 12 metabolic enzymes, glucose, lactate, and nicotinamide adenine dinucleotide (NADH) in the serum, the cytokine network and central metabolic pathway network were investigated to compare the effects of the two staple foods on immunity and metabolism. Compared with steamed bread, baked bread increased (p < 0.05) concentrations of fractalkine and macrophage-derived chemokine, decreased (p < 0.05) the concentration of interleukin-1RA, increased (p < 0.05) the expression level of phosphofructokinase, and decreased (p < 0.05) the expression level of glucose-6-phosphate dehydrogenase in the serum. Two network analyses indicated that baked bread, as compared to the steamed bread, enhanced communication between immune cells, increased catabolism, and decreased anabolism. Further, a correlation analysis of cytokines and metabolic enzymes suggested that the two staple foods may affect metabolism by regulating the secretion of cytokines. These findings highlight how the same raw food material processed by different methods may have different impacts on immunity and metabolism in humans.

In this work the antifeedant effects of the halogenated monoterpenes 1-13 were tested against several divergent insect species. These compounds have been isolated from Plocamium cartilagineum (6 was isolated as an acetyl derivative), except for 4, which was isolated from Pantoneura plocamioides. We have also included the semisynthetic derivatives 1a, 2a, and 7. Compounds 1, 1a, 2, 4, 5, 7, 8-10, and 13 were antifeedants against Leptinotarsa decemlineata with varying potencies. The aphids Myzus persicae and Ropalosiphum padi were strongly deterred in the presence of compounds 2, 12, and 13. This effect was correlated with the electronic recording of their probing behavior. Compounds 2 and 12 were toxic to L. decemlineata and had selective cytotoxicity to insect-derived Sf9 cells. None of the tested compounds showed phytotoxic effects. The antifeedant and cytotoxic effects of these compounds were compared with those of the polyhalogenated insecticide gamma-hexachlorocyclohexane (lindane).

Organisms lacking external defense mechanisms have developed chemical defense strategies, particularly through the production of secondary metabolites with antibiotic or repellent effects. Secondary metabolites from marine organisms have proven to be an exceptionally rich source of small molecules with pharmacological activities potentially beneficial to human health. (+)-Aeroplysinin-1 is a secondary metabolite isolated from marine sponges with a wide spectrum of bio-activities. (+)-Aeroplysinin-1 has potent antibiotic effects on Gram-positive bacteria and several dinoflagellate microalgae causing toxic blooms. In preclinical studies, (+)-aeroplysinin-1 has been shown to have promising anti-inflammatory, anti-angiogenic and anti-tumor effects. Due to its versatility, (+)-aeroplysinin-1 might have a pharmaceutical interest for the treatment of different pathologies.