Enhancing french basil growth through synergistic Foliar treatment with copper nanoparticles and Spirulina sp.

BACKGROUND: This study investigates a novel idea about the foliar application of nanoparticles as nanofertilizer combined with a natural stimulant, blue-green algae Spirulina platensis L. extract, as a bio-fertilizer to achieve safety from using nanoparticles for enhancement of the growth and production of the plant. Thus, this experiment aimed to chemically synthesize copper nanoparticles via copper sulfate in addition to evaluate the impact of CuNPs at 500, 1000, and 1500 mg/L and the combination of CuNPs with or without microalgae extract at 0.5, 1, and 1.5 g/L on the morphological parameters, photosynthetic pigments accumulation, essential oil production, and antioxidant activity of French basil. RESULTS: The results revealed that foliar application of CuNPs and its interaction with spirulina extract significantly increased growth and yield compared with control, the treatments of 1000 and 1500 mg/L had less impact than 500 mg/L CuNPs. Plants treated with 500 mg/L CuNPs and 1.5 g/L spirulina extract showed the best growth and oil production, as well as the highest accumulation of chlorophylls and carotenoids. The application of CuNPs nanofertilizer caused a significant increase in the antioxidant activity of the French basil plant, but the combination of CuNPs with spirulina extract caused a decrease in antioxidant activity. CONCULOSION: Therefore, foliar application of natural bio-fertilizer with CuNPsis necessary for obtaining the best growth and highest oil production from the French basil plant with the least damage to the plant and the environment.

The impact of polystyrene nanoplastics (PSNPs) on physiological and biochemical parameters of the microalgae Spirulina platensis.

Nanoplastics, as emerging pollutants, have harmful effects on living organisms and the environment, the mechanisms and extent of which remain unclear. Microalgae, as one of the most important biological groups in the food chain and sensitive environmental indicators to various pollutants, are considered a suitable option for investigating the effects of nanoplastics. In this study, the effects of polystyrene nanoplastics on the growth rate, dry weight, chlorophyll a and carotenoid levels, proline, and lipid peroxidation in the Spirulina platensis were examined. Three concentrations of 0.1, 1, and 10 mg L-1 of PSNPs were used alongside a control sample with zero concentration, with four repetitions in one-liter containers for 20 days under optimal temperature and light conditions. Various analyses, including growth rate, dry weight, proline, chlorophyll a and carotenoid levels, and lipid peroxidation, were performed. The results indicated that exposure to PSNP stress led to a significant decrease in growth rate, dry weight, and chlorophyll a and carotenoid levels compared to the control sample. Furthermore, this stress increased the levels of proline and lipid peroxidation in Spirulina platensis. Morphological analysis via microscopy supported these findings, indicating considerable environmental risks associated with PSNPs.

Assessing the Impact of Hexavalent Chromium (Cr VI) at Varied Concentrations on Spirulina platensis for Growth, Metal Sorption, and Photosynthetic Responses.

Spirulina platensis, a photosynthetic cyanobacterium, has garnered attention for its potential role in environmental remediation due to its ability to absorb and metabolize toxic heavy metals. Understanding its response toward toxicity of one of the most common contaminants, Cr(VI) is crucial for assessing its efficacy in bioremediation efforts. This study aims to investigate the physiological and biochemical responses of Spirulina platensis to varying concentrations of Cr(VI) from 0.5 to 5 ppm, shedding light on its potential as a bioindicator for environmental contamination and its suitability for bioremediation purposes. The impact of Cr(VI) on cell density, biosorption, pigment levels, nutrient content, fluorescence response, and photosynthetic efficiency was examined. The study revealed a gradual reduction in cell density, biomass production, and biosorption efficiency with increasing Cr(VI) concentrations. Pigment levels, carbohydrate, protein, and lipid content showed significant decreases, indicating physiological stress. Fluorescence response and photosynthetic efficiency were also adversely affected, suggesting alterations in electron transfer dynamics. A threshold for chromium toxicity was observed at 0.5 ppm, beyond which significant physiological disturbances occurred. This investigation highlights the sensitivity of Spirulina platensis to Cr(VI) toxicity and its potential as a bioindicator for heavy metal contamination. Metal sorption was highest in 0.5 ppm Cr(VI) with 56.56% removal. Notably, at lower concentrations, Cr(VI) acted as an intermediate electron acceptor, enhancing the electron transport chain and potentially increasing biomass under controlled conditions. The findings underscore the importance of understanding the mechanisms underlying heavy metal stress in microalgae for effective environmental remediation strategies. The research highlights the dual role of chromium(VI) in influencing S. platensis, depending on the concentration, and underscores the importance of understanding metal ion interactions with photosynthetic organisms for potential applications in bioremediation.

The extracellular polymeric substances (EPS) accumulation of Spirulina platensis responding to Cadmium (Cd2+) exposure.

Spirulina platensis can secrete extracellular polymeric substances (EPS) helping to protect damage from stress environment, such as cadmium (Cd2+) exposure. However, the responding mechanism of S. platensis and the secreted EPS to exposure of Cd2+ is still unclear. This research focuses on the effects of Cd2+ on the composition and structure of the EPS and the response mechanism of EPS secretion from S. platensis for Cd2+ exposure. S. platensis can produce 261.37 mg·g-1 EPS when exposing to 20 mg·L-1 CdCl2, which was 2.5 times higher than the control group. The S. platensis EPS with and without Cd2+ treatment presented similar and stable irregularly fibrous structure. The monosaccharides composition of EPS in Cd2+ treated group are similar with control group but with different monosaccharides molar ratios, especially for Rha, Gal, Glc and Glc-UA. And the Cd2+ treatment resulted in a remarkable decline of humic acid and fulvic acid content. The antioxidant ability of S. platensis EPS increased significantly when exposed to 20 mg·L-1 CdCl2, which could be helpful for S. platensis protecting damage from high concentration of Cd2+. The transcriptome analysis showed that sulfur related metabolic pathways were up-regulated significantly, which promoted the synthesis of sulfur-containing amino acids and the secretion of large amounts of EPS.

Spirulina platensis en el tratamiento de la obesidad y de algunas de sus consecuencias / Spirulina platensis in the Treatment of Obesity and some of its Consequences

Introducción: La Spirulina platensis constituye un sustancial reservorio de nutrientes y de alimentos funcionales con un bajo contenido de calorías. Aunque en la literatura se mencionan varias cualidades benéficas, una de ellas es aumentar la sensación de saciedad, lo que abre la posibilidad de ser empleada en la prevención y tratamiento de la obesidad y de algunas de sus consecuencias. Objetivo: Describir el papel de la Spirulina platensis en el tratamiento de la obesidad y de algunas de sus consecuencias. Métodos: Se realizó una búsqueda de literatura relevante sobre el tema en el primer cuatrimestre de 2020. Se utilizaron como buscadores de información científica: Pubmed, Scielo, Google y Google Académico. La estrategia de búsqueda incluyó los siguientes términos como palabras clave: Espirulina; Spirulina platensis; Obesidad; Exceso de peso. Se evaluaron artículos de revisión, de investigación y páginas Web que, en general, tenían menos de 10 años de publicados, en idioma español, portugués e inglés, y que hicieran referencia específicamente al tema de estudio a través del título. Fueron excluidos los artículos que no cumplieron con estas condiciones. Esto permitió el estudio de 75 referencias bibliográficas, de las cuales 51 se citaron en el presente artículo. Conclusiones: La Spirulina platensis representa una opción como suplemento nutraceútico y funcional, con valor preventivo y coadyuvante en el tratamiento de la obesidad y de algunas de sus consecuencias, al menos a corto plazo(AU)

Introduction: Spirulina platensis is a substantial reservoir of functional foods and nutrients with low calorie content. Although several beneficial qualities are mentioned in the scientific literature, one of them is to increase the feeling of satiety, which opens the possibility of being used for preventing and treating obesity, as well as some of its consequences. Objective: To describe the role of Spirulina platensis for treating obesity and some of its consequences. Methods: A search of relevant literature on the subject was carried out in the first four months of 2020. The following scientific information search engines were used: Pubmed, Scielo, Google and Google Scholar. The search strategy included the following terms as keywords: espirulina [spirulina], Spirulina platensis, obesidad [obesity], exceso de peso [overweight]. Review articles, research articles and Web pages were assessed, which, in general, had been published within less than ten years, in Spanish, Portuguese and English, and which made specific reference to the study topic through their titles. Articles that did not meet these conditions were excluded. This allowed the study of 75 bibliographic references, of which 51 were cited in this article. Conclusions: Spirulina platensis is an option as a nutraceutical and functional supplement, with preventive and coadjutant value for the treatment of obesity and some of its consequences, at least in the short term(AU)