Explore the vast range of titles available.

Currently, the use of biostimulants in agriculture is a tool for mitigating certain environmental stresses. Brown algae extracts have become one of the most important categories of biostimulants in agriculture, and are derived from the different uses and positive results obtained under optimal and stressful conditions. This study aimed to examine the efficacy of a foliar application of a hydroalcoholic extract of Sargassum spp. and two controls (a commercial product based on Ascophyllum nodosum and distilled water) with regard to growth, the antioxidant system, and the expression of defense genes in tomato seedlings grown in nonsaline (0 mM NaCl) and saline (100 mM NaCl) conditions. In general, the results show that the Sargassum extract increased the growth of the seedlings at the end of the experiment (7.80%) compared to the control; however, under saline conditions, it did not modify the growth. The Sargassum extract increased the diameter of the stem at the end of the experiment in unstressed conditions by 14.85% compared to its control and in stressful conditions by 16.04% compared to its control. Regarding the accumulation of total fresh biomass under unstressed conditions, the Sargassum extract increased it by 19.25% compared to its control, and the accumulation of total dry biomass increased it by 18.11% compared to its control. Under saline conditions, the total of fresh and dry biomass did not change. Enzymatic and nonenzymatic antioxidants increased with NaCl stress and the application of algal products (Sargassum and A. nodosum), which was positively related to the expression of the defense genes evaluated. Our results indicate that the use of the hydroalcoholic extract of Sargassum spp. modulated different physiological, metabolic, and molecular processes in tomato seedlings, with possible synergistic effects that increased tolerance to salinity.

Agricultural vegetable products always seek to meet the growing demands of the population; however, today, there are great losses in supply chains and in the sales stage. Looking for a longer shelf life of fruits and vegetables, postharvest technologies have been developed that allow an adequate transfer from the field to the point of sale and a longer shelf life. One of the most attractive methods to improve quality and nutritional content and extend shelf life of fruits and vegetables is the incorporation of bioactive compounds with postharvest technologies. These compounds are substances that can prevent food spoilage and the proliferation of harmful microorganisms and, in some cases, act as a dietary supplement or provide health benefits. This review presents an updated overview of the knowledge about bioactive compounds derived from plant residues, the techniques most used for obtaining them, their incorporation in edible films and coatings, and the methods of microbial inhibition.

The growing demand for food production and increasing stress scenarios increase the crucial need for sustainable alternatives to achieve increased crop yield and quality without affecting the environment. The use of brown macroalgae, being a renewable resource, is a promising option with various application options in agricultural systems, mainly in the form of extracts, direct applications, and compost. Brown algae are a source of active biomolecules and minerals that are currently used as agricultural biostimulants, since they increase crop productivity. This type of biostimulants derived from brown algae improve seed germination, increase the accumulation of plant biomass by accelerating cell division and elongation, activating the antioxidant system of plants, making them more resistant to stress, and contributes to the absorption and translocation of nutrients present in the soil. These products are also compatible with other agricultural inputs, such as synthetic fertilizers and pesticides, which makes them ideal for comprehensive applications and maintaining a balance in agroecosystems. This review incorporates fundamental and applied aspects of brown seaweeds that impact yields, biochemical quality, physiology, stress mitigation, and soil properties. Based on the above, the review is divided into different Sections that show the formulation of brown seaweed products; their effect on crop yield, quality, and physiology; their effect on biotic and abiotic stress mitigation; and their impact on soil physical, chemical, and biological properties.

The valorization of agro-industrial residues through fermentation processes represents a sustainable approach to producing high-value bioproducts, such as microbial organic acids and fermentation-derived anti-browning agents, including kojic acid and kojic acid-rich fermented extracts. In this study, melon waste (non-commercial-quality or damaged fruit) was evaluated as an alternative carbon source (whole fruit) for kojic acid (KA) production by Aspergillus oryzae (ATCC 10124) under submerged fermentation. The effects of process variables such as pH, temperature, and nitrogen and carbon availability on KA synthesis were analyzed, and biomass growth and product formation were described using logistic and Luedeking–Piret kinetic models. Under optimal conditions (pH 5.5, 36 °C, 2.5 g/L melon dry matter, 2.5 g/L yeast extract, 100 rpm), KA production reached 1.64 g/L at a final time of 120 h. Kinetic analysis showed moderate fungal growth (μmax = 0.058 h−1; Xmax = 0.81 g/L), with KA formation following a mixed growth-associated pattern as described by the Luedeking–Piret model (α = 1.26 g KA/g X; β = 0.024 h−1), indicating sustained production during the stationary phase. The KA-rich fermented extract was subsequently applied as an anti-browning treatment on spineless prickly pear (Opuntia ficus-indica) cladodes. Short immersion times (0.5–1.0 min) in a 2 g/L KA solution significantly preserved luminosity (L*) and limited total color change (ΔE ≤ 5) during 4 days of storage at 28 °C, compared with water-treated controls, which exhibited accelerated darkening (ΔE ≈ 9–15). Prolonged immersion times induced tissue damage and color deterioration, indicating an optimal exposure window. These results demonstrate the feasibility of valorizing melon waste to obtain a KA-rich extract and support its potential application as a natural anti-browning agent in fresh-cut vegetables within a circular agrifood framework.

Currently, biostimulants in the horticultural sector are a tool that is being used to improve the yield and quality of vegetables under optimal and stressful growth conditions. In the present study, we evaluate the effects of foliar application of a hydroethanolic extract of Sargassum spp., a commercial extract based on Ascophyllum nodosum, and a control with distilled water on growth and biomass, stomatal conductance, photosynthetic pigments, enzymatic and non-enzymatic antioxidants, protein content, and the expression of defense genes in tomato plants (Solanum lycopersicum L.) without stress and with high-temperature stress (45 °C). The results showed that Sargassum spp. extract only increased the height of tomato plants under stress-free conditions (2.71%) in the last evaluation. The aboveground and total dry biomass of the plants were increased by Sargassum spp. extract under stress-free conditions by 9.56 and 8.58%, respectively. Under stress conditions, aboveground dry biomass was increased by 6.66% by Sargassum spp. extract. Stomatal conductance, photosynthetic pigments, protein content, enzymatic and non-enzymatic antioxidants, and defense gene expression of tomato plants were positively modified with the use of Sargassum spp. and A. nodosum extract under high-temperature stress conditions. Under stress-free conditions, the described variables were positively modified except for gene expression, where some genes were expressed and others were repressed. The results indicate that extracts of Sargassum spp. and A. nodosum are effective in mitigating high-temperature stress, making their use a promising alternative for inducing resistance in plants to the daily adversities of climate change.

Sargassum is a brown macroalga that has become a general environmental problem in the Mexican Caribbean. Despite the negative effects on the beaches, the algae contain compounds of biotechnological and agronomic interest. The possibility of using sargassum as a substrate under liquid media fermentation (LMF) processes will allow the obtention of bioactive compounds. In this research, five species of Sargassum from the Puerto Morelos region were collected from the beach. The samples were divided into natural Sargassum and washed Sargassum, and the total phenolic compounds (TPC), flavonoids (F), and antioxidant capacity (AOxC) were determined. Once the material was characterized, it was fermented in the LMF process using the Aspergillus niger strain, where the obtained extracts were analyzed. Three holopelagic and one benthic species were identified. The proximal analysis of the seaweed in natural and washed conditions shows adequate carbon–nitrogen ratio values for use as a substrate for microbial degradation. Comparing the fermented extracts with fresh Sargassum, the analyses showed a TPC increase for washed Sargassum fermentation and a TPC decrease for natural Sargassum fermentation; the flavonoid content reached 8-fold higher in the washed Sargassum fermentation. An average AOxC of 57% was achieved during the washed Sargassum LMF process, with a maximum of 69% of ABTS inhibition. Considering these results, Sargassum can be used as a substrate in LMF processes to obtain bioactive compounds.

The use of biostimulants can help to mitigate the conditions of biotic and abiotic stresses in crops by enhancing the crop yield and product nutrients. The novelty of this research was to produce a biostimulant for the tomato cultivation through fermentation of pomegranate waste, evaluating in the crop the effect on the growth, development, and quality of tomato fruits. Pomegranate bagasse was used as a substrate during the liquid fermentation using Aspergillus niger M4 strain. Three applications of fermented extract were made in three phenological crop stages for each of the four different treatments. The biotechnological process allowed the transformation of pomegranate residues, increasing the content of antioxidant activity and catechin in 467% and 315%, respectively. The fermentation enabled the mineral content modification, such as the condensed tannins, zinc, magnesium, and antioxidant capacity. By applying the fermented extract of pomegranate, an increase of 34% in crop yield and a 32% in the lycopene content in tomato fruit was obtained. The use of a fermentative process enables the pomegranate waste mineral modification, enhancing the biostimulant capacity of pomegranate residues. The foliar application of a raw pomegranate fermented extract increases the crop yield and nutritional quality of the tomato fruits.

Biostimulants are currently essential for agriculture as they increase crop productivity and quality sustainably. The aim of this work was to evaluate the effects of biostimulation on the application of nanochitosan–iodine complexes (nCS-I) on tomato plants. Leaf samples were taken for analysis of total protein content, photosynthetic pigments, antioxidant enzymatic activity, mineral and iodine contents, gene expression, and shelf life in tomato fruit. The catalase (CAT), glutathione peroxidase (GPX), ascorbate peroxidase (APX), and superoxide dismutase (SOD) activities increased significantly with the application of nanochitosan (nCS) and nanochitosan–potassium iodate (nCS-KIO3) and nanochitosan–potassium iodide (nCS-KI) complexes and the iodine salts potassium iodate (KIO3) and potassium iodide (KI). The total protein content and photosynthetic pigments also increased significantly with the application of the treatments. The mineral and iodine contents did not change with the application of the treatments. Similarly, overexpression of the SOD, GPX, and CAT genes was observed. Finally, in the shelf life test, an increase in the total phenols and antioxidant capacity was observed with the application of the treatments. This study shows that the use of nCS-I complexes can modulate different transcriptional and post-translational processes with possible synergistic effects on the antioxidant metabolism of tomato plants.

The strawberry fruit (Fragaria × ananassa Duch.) is appreciated for its aroma, color, texture and nutritional value. In conventional agriculture, the use of fertilizers damages the environment since it causes loss of soil fertility, salinity and its erosion, hence production alternatives, without harming the environment, are sought. The objective of this study was to evaluate the effect of a biostimulant based on humic substances and rhizobacteria, on the production and quality of the strawberry cultivar ‘San Andreas’. Strawberry plants cultivar ‘San Andreas’ were treated with fulvic acids + mixture of microorganisms, humic acids + Pseudomonas fluorescens, fulvic acids + Azospirillum brasilense, fulvic acids + Pseudomonas fluorescens and the mixture AH and AF + Azospirillum brasilense with two doses (d1, d2) in total 10 treatments were applied plus the control. Humic substances were applied every 15 days and rhizobacteria every 30 days. The results showed that the AFyAzoz d1 increased over control plants, the number of leaves in 38.3%, root volume in 42.6%, the fresh weight in 130% and dry weight in 63.8%, the number of fruits 50.0% and the yield in 59.5%. The AFyPF d1 favored Photosynthesis in 127.3%; AFyPF d1 increased TSS in 25%, AFyPF d2 vitamin C in 17.1% and MHyF + Azoz d1 increased in 20% the content of Phenols. Humic substances plus rhizobacteria are an ecological alternative to be used as biostimulant in the production and quality of strawberry plants.

Plants from arid zones of Mexico are an interesting source of phytochemicals that exhibit a large number of biological properties. In this context, Rhus microphylla (Rm) and Myrtillocactus geometrizans (Mg) fruits have been used as folk remedies and to make traditional foods, respectively; however, studies on their composition and bioactivity are limited. Thus, the objective of this work was to evaluate the yields, phenolic composition, and bioactive properties (scavenging and reducing capacities, antiproliferative, and antifungal) of aqueous and hydroalcohol extracts of Rm and Mg fruits obtained by conventional agitation and ohmic heating (OH). The results showed that the Rm fruit extracts had the highest total phenolic content (TPC) values and the strongest scavenging and reducing capacities compared to those of Mg fruits, being characterized by the presence of gallic acid, while the composition of the Mg extracts varied with respect to the extraction conditions used. Regarding antifungal activity in vitro against two phytopathogenic fungi, Rhizopus stolonifer and Fusarium oxysporum, the hydroalcohol extracts obtained by conventional agitation of both plants (RmH-C and MgH-C) showed the best inhibitory effect, respectively. Interestingly, none of the extracts under study presented cytotoxicity against the noncancerous ARPE-19 cell line, while three extracts of Rm fruit exhibited a moderate antiproliferative activity against HeLa (cancerous) cell line. These findings reveal for the first time the potential of Rm and Mg fruits as a new source of bioactive compounds for future industrial applications.