Influence of seaweed extracts on growth, phytochemical contents and antioxidant capacity of cowpea (Vigna unguiculata L. Walp)

Exploring the Therapeutic Potential of Podophyllum hexandrum Root Extract: Chemical Composition, Antimicrobial Efficacy, and Antioxidant and Anticancer Activities

Medicinal plants have been used for centuries as therapeutic compounds to address various health issues. Their rich phytochemical composition offers diverse bioactive substances with potential health benefits. This study aimed to explore the therapeutic potential of Podophyllum hexandrum root extract by investigating its chemical composition and antimicrobial, antioxidant, and anticancer properties. The phytochemical profiling of P. hexandrum root was conducted using GC-MS analysis, which identified 26 compounds in the extract. The ethanolic root extract displayed strong inhibitory effects in the well diffusion assay against all tested microbes, with minimum inhibitory concentration (MIC) values ranging from 64 to 256 μg/mL. Candida albicans exhibited the lowest MIC value of 64 μg/mL. The antioxidant activity of the extracts was compared to standard antioxidant, revealing a dose-dependent response with a notable radical scavenging activity of 59.23% at 100 μg/mL. Furthermore, the extract demonstrated strong cytotoxic effects against the human cancer cell line HT-29, with IC50 values of 38.20 and 32.5 μg/mL for 24 and 48 h. Overall, this study emphasizes the remarkable antibacterial, antioxidant, and anticancer properties of P. hexandrum root extract.

Investigating the Medicinal Potential of Lavatera cashmeriana Leaf Extract: Phytochemical Profiling and In Vitro Evaluation of Antimicrobial, Antioxidant, and Anticancer Activities

This study investigated the medicinal potential of Lavatera cashmeriana, a plant traditionally known for its therapeutic properties. The aim was to identify the phytocompounds in L. cashmeriana leaf extract and evaluate its antibacterial, antioxidant, and anticancer effects. Gas chromatography-mass spectrometry analysis was employed to characterize the phytochemical composition of the ethanol extract derived from L. cashmeriana leaves. The antimicrobial potential was assessed through the well diffusion technique, targeting Escherichia coli, Enterococcus faecalis, Pseudomonas aeruginosa, Staphylococcus aureus, and Candida albicans. The 2,2-diphenyl-1-picrylhydrazyl assay was conducted to assess antioxidant capabilities, while cytotoxicity against the A549 cancer cell line was determined via the MTT assay. GC-MS analysis identified ten different compounds, with phytol, 1-Eicosanol, and 2,6,10-trimethyl,14-ethylene-14-pentadecne being the most prevalent. The extract exhibited notable antimicrobial efficacy against all bacteria with MIC values ranging from 62.5 to 250 µg/mL. However, C. albicans did not respond. The extract exhibited antioxidative properties with an IC50 value of 86 µg/mL and cytotoxicity with an IC50 value of 69.95 µg/mL against the A549 cancer cell line. The results derived from this study supported the historical use of L. cashmeriana as a medicinal plant and suggested that it can potentially treat a wide range of medical ailments. The identified phytocompounds and the demonstrated antibacterial, antioxidant, and anticancer effects provide scientific evidence for its medicinal properties. However, further investigations are needed to fully understand its safety profile, efficacy, and mechanism of action before recommending it for therapeutic purposes.

Potential of algal-based products for the management of potato brown rot disease

BACKGROUND

Ralstonia solanacearum causes potato brown rot disease, resulting in lower crop's production and quality. A sustainable and eco-friendly method for controlling the disease is required. Algae's bioactive chemicals have shown the potential to enhance plant defenses. For the first time, the efficacy of foliar application of Acanthophora spicifera and Spirulina platensis seaweed extracts, along with the utilization of dried algal biomasses (DABs) of Turbinaria ornata and a mixture of Caulerpa racemosa and Cystoseira myrica (1:1)on potato yield and brown rot suppression were investigated under field conditions. Field experiments were conducted in three locations: Location 1 (Kafr Shukr district, Kaliobeya governorate), Location 2 (Moneira district, Kaliobeya governorate), and Location 3 (Talia district, Minufyia governorate). Locations 1 and 2 were naturally infested with the pathogen, while location 3 was not. The study evaluated potato yield, plant nutritive status and antioxidants, soil available nitrogen-phosphorus-potassium (N-P-K), and organic matter percentage. Additionally, the shift in soil microbial diversity related to R. solanacearum suppression was examined for the most effective treatment.

RESULTS

The results revealed that seaweed extracts significantly increased potato yield at all locations, which correlated with higher phosphorus absorption, while T. ornate DAB increased potato yield only at location 2, accompanied by noticeable increases in soil nitrogen and plant phosphorus. The mixed DABs of C. racemosa and C. myrica demonstrated greater disease suppression than foliar applications. The disease-suppressive effect of the mixed DABs was accompanied by significant increases in flavonoids and total antioxidant capacity (TAC). Moreover, the application of mixed DABs increased soil bacterial biodiversity, with a higher abundance of oligotrophic marine bacterial species such as Sphingopyxis alaskensis and growth-promoting species like Glutamicibacter arilaitensis, Promicromonospora sp., and Paenarthrobacter nitroguajacolicus in all three locations compared to the untreated control. Klebsiella sp., Pseudomonas putida, and P. brassicacearum abundances were increased by the mixed DABs in Location 1. These species were less abundant in locations 2 and 3, where Streptomyces sp., Bacillus sp., and Sphingobium vermicomposti were prevalent.

CONCLUSIONS

The results demonstrated that the used seaweed extracts improved potato yield and phosphorous absorption, while the mixed DABs potentially contributed in disease suppression and improved soil microbial diversity.

Effect of foliar application of bio-stimulants on growth, yield and nutritional quality of broccoli

Broccoli is one of important cole crop grown all over the world due to its unique nutritional profile consumed fresh as well as processed. It contains a wide range of nutrients, vitamins, minerals and specific anti-cancer compounds such as glucosinolates. Broccoli cultivation in Pakistan is increasing rapidly, however, till now there is no standardized cropping technology for broccoli cultivation under local climate. Considering research gap (lack of suitable varieties, poor growth, and unavailability of optimized crop technology), trial was conducted at Vegetable research area, Institute of Horticultural Sciences, University of Agriculture, Faisalabad to evaluate the impact of bio-stimulants on different broccoli cultivars under local climatic conditions. The set of experimental treatments was laid out in Randomized Complete Block Design (RCBD) with three replications. Pre-harvest application of Isabion and Seaweed extract significantly enhanced the plant height (11%), dry weight (4%), leaf area (7%), and yield plant-1 (5%). Moreover, Isabion and seaweed extract application led to the increase in antioxidant enzymes i.e., superoxide dismutase (18%), peroxidase (38%) and catalase (12%). In crux, the foliar application of bio-stimulants (Isabion and seaweed extract) on broccoli enhanced the growth, yield, and contents of antioxidant enzymes.

The Phenolic Composition of Hops (Humulus lupulus L.) Was Highly Influenced by Cultivar and Year and Little by Soil Liming or Foliar Spray Rich in Nutrients or Algae

The interest in expanding the production of hops outside the traditional cultivation regions, mainly motivated by the growth of the craft brewery business, justifies the intensification of studies into its adaptation to local growing conditions. In this study, four field trials were undertaken on a twenty-year-old hop garden, over periods of up to three years to assess the effect of important agro-environmental variation factors on hop phenol and phenolic composition and to establish its relationship with the elemental composition of hop cones. All the field trials were arranged as factorial designs exploring the combined effect of: (1) plots of different vigour plants × year; (2) plots of different plant vigor × algae- and nutrient-rich foliar sprays × year; (3) plot × liming × year; and (4) cultivars (Nugget, Cascade, Columbus) × year. Total phenols in hops, were significantly influenced by most of the experimental factors. Foliar spraying and liming were the factors that least influenced the measured variables. The year had the greatest effect on the accumulation of total phenols in hop cones in the different trials and may have contributed to interactions that often occurred between the factors under study. The year average for total phenol concentrations in hop cones ranged from 11.9 mg g−1 to 21.2 mg g−1. Significant differences in quantity and composition of phenolic compounds in hop cones were also found between cultivars. The phenolic compounds identified were mainly flavonols (quercetin and kaempferol glycosides) and phenolic carboxylic acids (p-coumaric and caffeic acids).

Sustainable Approaches to Boost Yield and Chemical Constituents of Aromatic and Medicinal Plants by Application of Biostimulants

INTRODUCTION

Biostimulants consist of natural ingredients, metabolites of fermentation, micro-organisms, algae or plant extracts, bacteria, mushrooms, humus substances, amino acids, biomolecules, etc. Methods: In this study, all relevant English-language articles were collected. The literature was reviewed using the keywords of biostimulant, medicinal plant, aromatic plant, natural products, and pharmaceutical benefits from Google Scholar, Scopus, and PubMed databases.

RESULTS

The significant and promoting impact of biostimulants has been reported for different medicinal and aromatic plants, such as salicylic acid for ajuga, artichoke, ajwain, basil, common rue, common sage, common thyme, coneflower, coriander, dendrobium, desert Indian wheat, dragonhead, fennel, fenugreek, feverfew, ginger, groundnut, guava, henna, Iranian soda, lavender, lemon balm, lemongrass, Malabar spinach; seaweed extract on almond, bird,s eye chili; amino acids on artemisia, broccoli, chamomile, beneficial bacteria on ashwagandha; humic acid on black cumin, cannabis, chicory, garlic, gerbera, Hungarian vetch, Moldavian dragonhead, niger plant; chitosan on dragon fruit, marigold, milk thistle, etc. The suggested mechanisms include the stimulatory impacts on the activity of enzymes involved in different biosynthetic processes, the hormone-like activity of biostimulant compounds and the improvement of nutrient uptake of plants.

CONCLUSION

The current manuscript gives many examples of the potential of biostimulants for medicinal and aromatic plant production. However, further studies are needed to better understand the effectiveness of different biostimulants and foliar applications in sustainable agriculture.

Harnessing Synergistic Biostimulatory Processes: A Plausible Approach for Enhanced Crop Growth and Resilience in Organic Farming

Simple Summary

Demand for organically grown crops has risen globally due to its healthier and safer food products. From a sustainability perspective, organic farming offers an eco-friendly cultivation system that minimizes agrochemicals and producing food with little or no environmental footprint. However, organic agriculture’s biggest drawback is the generally lower and variable yield in contrast to conventional farming. Compatible with organic farming, the selective use of biostimulants can close the apparent yield gap between organic and conventional cultivation systems. A biostimulant is defined as natural microorganisms (bacteria, fungi) or biologically active substances that are able to improve plant growth and yield through several processes. Biostimulants are derived from a range of natural resources including organic materials (composts, seaweeds), manures (earthworms, fish, insects) and extracts derived from microbes, plant, insect or animal origin. The current trend is indicative that a mixture of biostimulants is generally delivering better growth, yield and quality rather than applying biostimulant individually. When used correctly, biostimulants are known to help plants cope with stressful situations like drought, salinity, extreme temperatures and even certain diseases. More research is needed to understand the different biostimulants, key components, and also to adjust the formulations to improve their reliability in the field.

Abstract

Demand for organically grown food crops is rising substantially annually owing to their contributions to human health. However, organic farm production is still generally lower compared to conventional farming. Nutrient availability, content consistency, uptake, assimilation, and crop responses to various stresses were reported as critical yield-limiting factors in many organic farming systems. In recent years, plant biostimulants (BSs) have gained much interest from researchers and growers, and with the objective of integrating these products to enhance nutrient use efficiency (NUE), crop performance, and delivering better stress resilience in organic-related farming. This review gave an overview of direct and indirect mechanisms of microbial and non-microbial BSs in enhancing plant nutrient uptake, physiological status, productivity, resilience to various stressors, and soil-microbe-plant interactions. BSs offer a promising, innovative and sustainable strategy to supplement and replace agrochemicals in the near future. With greater mechanistic clarity, designing purposeful combinations of microbial and non-microbial BSs that would interact synergistically and deliver desired outcomes in terms of acceptable yield and high-quality products sustainably will be pivotal. Understanding these mechanisms will improve the next generation of novel and well-characterized BSs, combining microbial and non-microbial BSs strategically with specific desired synergistic bio-stimulatory action, to deliver enhanced plant growth, yield, quality, and resilience consistently in organic-related cultivation.

Alginate and fucoidan changes the bacterial community in different directions and the alginate or fucoidan degrading bacteria isolated from paddy soil promotes the plant growth

Seaweed and its extracts have been developed as fertilizers because they possess plant-growth-promoting and antibacterial compounds. For use as fertilizers, the major carbohydrates in seaweed, including fucoidan and alginate, need to be efficiently digested in the soil. We isolated fucoidan/alginate degrading bacteria from paddy soil and verified its use as a biofertilizer. Results show that Stenotrophomonas pavanii has a high alginate degrading activity, and also stimulating melon, pepper, and tomato growth. The growth stimulation effect of the bacteria was enhanced by alginate treatment. Bacillus sp. was isolated as a fucoidan degrading bacterium and this bacterium was also able to stimulate melon growth. Using 16S ribosomal DNA analysis, fucoidan/alginate resistant or susceptible bacteria were successively selected. Bacteria with increased population due to fucoidan and alginate had specificity to each carbohydrate, whereas those with decreased population showed susceptibility to both carbohydrates. This report demonstrates some bacteria for their use as biofertilizers with seaweed and demonstrated that a high throughput method is efficient in identifying bacteria with specific properties.

Diplotaxis tenuifolia (L.) DC. Yield and Quality as Influenced by Cropping Season, Protein Hydrolysates, and Trichoderma Applications

Increasing attention is being given to plant biostimulants as a sustainable farming practice aimed to enhance vegetable crop performance. This research was conducted on greenhouse-grown perennial wall rocket (Diplotaxis tenuifolia (L.) DC.), comparing three biostimulant treatments (legume-derived protein hydrolysates, Trichoderma harzianum T22, and protein hydrolysates + Trichoderma harzianum T22) plus an untreated control, in a factorial combination with three cropping seasons (autumn-winter, winter, winter-spring). Measurements were performed on leaf yield components, colorimetric indicators, mineral composition, bioactive compounds, and antioxidant activity. Leaf marketable yield and mean weight, as well as plant dry weight, showed the highest values in winter crop cycle. Biostimulant treatments resulted in 18.4% and 26.4% increase in leaf yield and number of leaves per rosette, respectively, compared to the untreated control. Protein hydrolysates led to the highest plant dry weight (+34.7% compared to the control). Soil plant analysis development (SPAD) index as well as NO₃, PO₄, SO₄, and Ca contents were influenced more during the winter-spring season than the winter cropping season. The winter production season resulted in a 19.8% increase in the leaf lipophilic antioxidant activity, whereas the hydrophilic antioxidant activity was 34.9% higher during the winter-spring season. SPAD index was the highest with protein hydrolysates + Trichoderma applications, which also increased the colorimetric parameters compared to the untreated control. The treatment with protein hydrolysates + Trichoderma enhanced N, PO₄, Mg, and Na contents, compared to both biostimulants applied singly and to the untreated control. Both biostimulants applied alone or the protein hydrolysates + Trichoderma combination led to the increase of the lipophilic and hydrophilic antioxidant activity, as well as ascorbic acid and chlorophyll b, compared to the untreated control. The present research revealed that protein hydrolysates and Trichoderma single applications, and even more their combination in the case of some nutrients content, represent an effective tool for enhancing the yield and the quality attributes of perennial wall rocket produced under the perspective of sustainable crop system.

Effect of Vegetal- and Seaweed Extract-Based Biostimulants on Agronomical and Leaf Quality Traits of Plastic Tunnel-Grown Baby Lettuce under Four Regimes of Nitrogen Fertilization

Nitrogen (N) fertilizers play a crucial role in agriculture, representing a powerful tool for farmers for increasing yields throughout the seasons under both optimal and suboptimal conditions. At the same time, their synthetic/chemical nature could have several influences on ecosystems and human health. For this reason, there is an urgent need to find new and more sustainable means of production to increase plant productivity and optimize nitrogen use. An experiment was conducted in a plastic tunnel to assess the response of baby lettuce crop to the foliar application of three plant biostimulants (PBs): Legume-derived protein hydrolysate (LDPH) ‘Trainer®’, tropical plant extract (TPE) ‘Auxym®’ and seaweed extract (SwE) from Ecklonia maxima ‘Kelpak®’ under different N rates of 0, 10, 20 and 30 kg N·ha−1. The responses of baby lettuce plants were assessed in terms of yield, growth parameters and physicochemical composition of the leaves. The fresh yield of baby lettuce in both biostimulant-treated and untreated plants was positively affected by increasing N rates from 0 to 20 kg N·ha−1, reaching a plateau thereafter indicating luxury N conditions at 30 kg N·ha−1. However, high N fertilizer application (20 and especially 30 kg N·ha−1) resulted in undesirable decreases in antioxidant activities and total ascorbic acid (TAA). Under non-fertilized regimens, foliar PBs application boost growth and yield of baby lettuce in comparison to non-treated plants. Foliar spray with LDPH and especially SwE elicited significant increases in marketable fresh yield (averaging 14%, 6% and 7% at 10, 20 and 30 kg N·ha−1, respectively) compared to TPE and untreated plants. Improved agronomical performance of baby lettuce under optimal (10 kg N ha−1) and especially suboptimal N regimens (0 kg N ha−1) was associated with increasing photochemical efficiency and a better activity of photosystem II (higher Soil Plant Analysis Development-SPAD index and chlorophyllous pigments biosynthesis). The application of LDPH enhanced antioxidant capacity and TAA in baby lettuce leaf and did not increased nitrate content as recorded in SwE and TPE treatments. Overall, plant biostimulants may be considered as a sustainable tool of production to increase leafy vegetable productivity in low fertility soils.

Protein Hydrolysate or Plant Extract-based Biostimulants Enhanced Yield and Quality Performances of Greenhouse Perennial Wall Rocket Grown in Different Seasons

Research has been increasingly focusing on the environmentally friendly biostimulation of vegetable crop performances under sustainable farming management. An experiment was carried out in southern Italy on Diplotaxis tenuifolia to assess the effects of two plant biostimulants (Legume-derived protein hydrolysate, Trainer^®; Tropical plant extract, Auxym^®) and a non-treated control, in factorial combination with three crop cycles (autumn–winter; winter; and winter–spring) on leaf yield, photosynthetic and colour status, quality, elemental composition, antioxidant content and activity. Both biostimulants prevalently contain amino acids and soluble peptides, showing the major effects on crop performances, though Auxym also has a small percentage of phytohormones and vitamins. The biostimulants enhanced plant growth and the productivity of perennial wall rocket. The winter–spring cycle led to higher leaf yield than the winter one. The two plant biostimulants enhanced leaf dry matter, oxalic and citric acids, Ca and P concentrations, phenols and ascorbic acid content as well as antioxidant activity, but did not increase nitrate content. A presumed mechanism involved in the enhancement of crop production could be attributed to the improvement of mineral nutrient availability and uptake. The winter–spring cycle elicited higher antioxidant content and activity than winter crops. Our current study shows that both the legume-derived protein hydrolysate and tropical plant extract represent an effective tool for boosting the yield, nutritional and functional quality of vegetable produce in the view of sustainable crop systems.