Spinach Leaf Research Articles

Spinach leaf disease identification based on deep learning techniques

Spinach leaf disease identification based on deep learning techniques

Phytoecdysteroids: Quantification in Selected Plant Species and Evaluation of Some Effects on Gastric Smooth Muscles.

Phytoecdysteroids (PEs) are naturally occurring steroid compounds, that have recently gained significant attention, due to their diverse biological activities and high therapeutic potential. The aim of the present study was to quantify some PEs including 20-hydroxyecdysterone (20-HE), ponasterone A (PA), and turkesterone (TU) in selected plant foods and Rhaponticum carthamoides extract. Furthermore, the effects of 20-HE, TU, and R. carthamoides extract, were investigated with in vitro methods using isolated smooth muscle tissues. The levels of 20-HE in the analyzed samples exhibited significant differences, with kaniwa seed extract containing the highest amount, followed by spinach leaf extract, quinoa seed extract, and asparagus stem extract. The in vitro analyses suggested that R. carthamoides extract exhibits dose-dependent cytotoxic effects on smooth muscle cells, with low doses promoting contraction and higher doses inducing relaxation. Additionally, the extract demonstrated a significant inhibitory effect on ACh-induced contractions, while 20-HE enhanced the contractile response. The current findings highlighted phytoecdysteroids' potential for modifying gastrointestinal motility.

Optimizing the green synthesis of antibacterial TiO2 - anatase phase nanoparticles derived from spinach leaf extract

Titanium dioxide nanoparticles, renowned for their abundance, non-toxicity, and stability, have emerged as indispensable components in various fields such as air purification, healthcare, and industrial processes. Their applications as photocatalysts and antibacterial agents are particularly prominent. The synthesis methods significantly influence the properties and subsequent applications of these nanoparticles. While several techniques exist, the biological approach using plant extracts offers advantages such as simplicity, biocompatibility, and cost-effectiveness. This study focused on the green synthesis of titanium dioxide nanoparticles utilizing spinach leaf extract. Within the scope of this investigation, the green synthesis of titanium dioxide nanoparticles through spinach leaf extract were synthesized and optimized, followed by a comprehensive examination of their morphological, structural, and chemical attributes with UV-visible spectroscopy, FTIR spectroscopy, XRD, FESEM, and EDX. The minimum inhibitory concentration (MIC) against E. coli and S. aureus was determined to evaluate their antibacterial potential. Optimal synthesis conditions were identified at 50 °C, using a 1/30 concentration and 20 ml of spinach leaf extract. Spherical anatase nanoparticles, ranging from 10 to 40 nm, were produced under these conditions. The change in the color of the extract, absorption at 247 nm, change and increase of the peak at 800 − 400 wavelengths, and the maximum intensity of X-ray diffraction at the angle of 25.367 with the crystal plane 101 were indications of the synthesis of these nanoparticles. Notably, the synthesized nanoparticles exhibited antibacterial activity with MIC values of 0.5 mg/ml against E. coli and 2 mg/ml against S. aureus. This research presents a novel, eco-friendly approach to synthesizing titanium dioxide nanoparticles with promising antibacterial properties.

Effect of spinach (Spinacia oleracea) leaf extract on the aluminum (Al) as a green corrosion inhibitor in HCl medium

Green corrosion inhibitors have recently attracted much attention due to their non-toxic properties, especially plant extracts. This study used spinach leaf extract (Spinacia oleracea) as a corrosion inhibitor on aluminum in an HCl medium. Spinach leaf extract (Spinacia oleracea) was obtained by maceration method, using ethanol as the solvent, which was then distilled to purify the extract. The corrosion inhibition properties were studied by the gravimetric method. The results showed that spinach leaf extract (Spinacia oleracea) can efficiently decrease the corrosion rate of aluminum in an HCl medium, achieving a maximum efficiency of 96.7742 %. Spinach leaf extract (Spinacia oleracea) formed a protective layer on the aluminum surface via adsorption and chemisorption, thus increasing surface coverage and blocking mass transfers. As the inhibitor concentration increases, the corrosion rate decreases, and the corrosion inhibition efficiency increases. This study shows that spinach leaf extract (Spinacia oleracea) is a viable organic corrosion inhibitor option with high efficiency.

Compost amendment in urban gardens: elemental and isotopic analysis of soils and vegetable tissues

Urban horticulture poses a sustainable form of food production, fosters community engagement and mitigates the impacts of climate change on cities. Yet, it can also be tied to health challenges related to soil contamination. This work builds on a previous study conducted on eleven urban gardens in the city of Vienna, Austria. Following the findings of elevated Pb levels in some soil and plant samples within that project, the present study investigates the elemental composition of soil and plants from two affected gardens 1 year after compost amendment. Inductively coupled plasma mass spectrometry (ICP-MS) analysis of skin, pulp and seeds of tomato fruits revealed minor variations in elemental composition which are unlikely to have an impact on food safety. In turn, a tendency of contaminant accumulation in root tips and leaves of radishes was found. Washing of lettuce led to a significant reduction in the contents of potentially toxic elements such as Be, Al, V, Ni, Ga and Tl, underscoring the significance of washing garden products before consumption. Furthermore, compost amendments led to promising results, with reduced Zn, Cd and Pb levels in radish bulbs. Pb isotope ratios in soil and spinach leaf samples taken in the previous study were assessed by multi-collector (MC-) ICP-MS to trace Pb uptake from soils into food. A direct linkage between the Pb isotopic signatures in soil and those in spinach leaves was observed, underscoring their effectiveness as tracers of Pb sources in the environment.Graphical

Total Flavonoid Content and Antioxidant Properties of Different Extraction Methods of Red Spinach Leaf (Amaranthus tricolor L.)

Red spinach leaf (Amaranthus tricolor L.) has been well-proven to contain flavonoids that exhibit antioxidant activities. In this study, a comparison between maceration and ultrasonic methods has been carried out to evaluate the effect of these two methods on the level of red spinach leaf flavonoid. In this study, for maceration 1, 2, and 3 days while for the ultrasonic method 10-, 20-, and 30-minutes time duration have been used. The ratios of material and solvent were 1:5 and 1:10. The flavonoid content was determined with the help of a spectrophotometer at a maximum wavelength of 436.80 nm. The antioxidant activity was evaluated by the DPPH method to obtain the IC50. The result of the study revealed that the highest flavonoid content of 4.27 mgQE/g and antioxidant activity (IC50) of 110.47 ppm were obtained by an ultrasonic under conditions of 1:10 ratio and 30-minute extraction time. Results of the study suggested a significant difference (p<0,05) in the isolation of total flavonoid contents and antioxidant activities in the maceration and ultrasonic. In these two methods, ultrasonic was found to be more efficient than maceration because of minimum time, the highest flavonoid content and antioxidant activity could be obtained.

Decellularized leaf-based biomaterial supports osteogenic differentiation of dental pulp mesenchymal stem cells.

Decellularized tissues are an attractive scaffolds for 3D tissue engineering. Decellularized animal tissues have certain limitations such as the availability of tissue, high costs and ethical concerns related to the use of animal sources. Plant-based tissue decellularized scaffolds could be a better option to overcome the problem. The leaves of different plants offer a unique opportunity for the development of tissue-specific scaffolds, depending on the reticulate or parallel veination. Herein, we decellularized spinach leaves and employed thesefor the propagation and osteogenic differentiation of dental pulp stem cells (DPSCs). DPSCs were characterized by using mesenchymal stem cell surface markers CD90, CD105 and CD73 and CD34, CD45 and HLA-DR using flow cytometry. Spinach leaves were decellularized using ethanol, NaOH and HCL. Cytotoxicity of spinach leaf scaffolds were analysed by MTT assay. Decellularized spinach leaves supported dental pulp stem cell adhesion, proliferation and osteogenic differentiation. Our data demonstrate that the decellularized spinach cellulose scaffolds can stimulate the growth, proliferation and osteogenic differentiation of DPSCs. In this study, we showed the versatile nature of decellularized plant leaves as a biological scaffold and their potential for bone regeneration in vitro.

An In-vitro Antioxidant and Antimicrobial Activity of Vitis vinifera Leaf Extract

Background: Vitis vinifera (Flame red grape) is known for its hepatoprotective, nephroprotective and cardioprotective activity of ethanolic and aqueous extracts of aerial parts has been reported but, due to presence of polyphenols, glycosides, saponins and alkaloid, the antioxidant and antimicrobial activity yet not to evaluated on salad plant and bacteria, respectively. Aim: This research examined grape (V. vinifera flaming red) leaf ethanolic extract (EE) as a bioactive resource. Methods: Ethanolic extract test, primarily to calculate the overall phenolic content by using the Folin-Ciocalteu technique and gallic acid taking as a reference. Similarly, flavonoid content measured using quercetin as a calibration curve. Antioxidant properties was confirmed by getting positive responses from different methods (DPPH, H2O2, FRAP and Phospho-Molybdenum). Antimicrobial activity tested against gram-positive bacteria (Lactobacillus cereus and Staphylococcus aureus) and gramnegative bacteria (Escherichia coli and Staphylococcus enterica ser. Typhimurium) in a broth microdilution test. The ethanolic extract (EE) are rich in antioxidant-rich phenolic compounds show minimum inhibition concentration (MIC) and minimum bactericidal concentration (MBC) for every given bacterium on beetroot and spinach leaves. Results: We investigate this extract’s total phenol, total flavonoid, and antioxidant and antibacterial properties. We also identify its main phenolic components, revealing its phytochemical diversity. We found that the EE had 39.29 gGAkg-1 dw of phenol and 96.05 gQE kg-1 dw of flavonoids. The EE scavenges DPPH, H2O2, FRAP, and PM radicals at 142, 168, 275, and 172 g TE kg-1, respectively. We reveal the complex character of this extract by revealing catechins, flavonoids, tannins, malic acid, enzymes, resveratrol, phenolic acids, flavonols, procyanidins, and anthocyanins. Salmonella enterica subsp. enterica serovar Typhimurium, Escherichia coli, Listeria monocytogenes, and Staphylococcus aureus are all inhibited by EE with a MIC range of 16 to 18 gL-1 (E. coli). The extract affects bacterial growth at different stages. The EE reduces spinach and beetroot leaf total bacterial load by 1.159 to 2.456 log drop when used as a sanitizer at 25 gL-1 (1.156–2.858 log reduction). Conclusion: This research work highlights grape leaf EE as a novel and appealing source of bioactive components with its strong antibacterial and antioxidant activities against common foodborne infectious agents. Our research reveals that leaf ethanolic extract could reduce human pathogenic microorganisms in fresh green vegetables, improving food safety.

Green marvel: Harnessing spinach leaves' power for enhanced photodegradation of various effluents with biogenic ZnO nanoparticles

This study investigates the use of ZnO NPs (Zinc oxide nanoparticles) derived from spinach leaf extracts in a sustainable photocatalytic technology to enhance the decomposition of hazardous effluents from refineries and paper mills. The biosynthesized ZnO NPs were characterized through X-ray diffraction (XRD), UV-Vis spectroscopy, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The XRD analysis reveals that ZnO NPs possess a hexagonal wurtzite structure, exhibiting a preferred arrangement of (101) planes. The synthesized ZnO NPs have a spherical shape, as seen in the SEM images. TEM analysis detected the size of the ZnO NPs to be between 35 and 40 nm. The results indicate that ZnO NPs produced via biosynthesis have photocatalytic activity in efficiently decomposing the organic chemicals found in gasoline refining effluent when exposed to light. At a pH of 8, the ZnO NPs exhibited the highest rate of degradation for toluene (84.26 %) and xylene (90.36 %) after being exposed to simulated sunlight for 240 min. In the context of the photocatalytic treatment of paper mill effluents, it has been shown that the subsequent cycles resulted in a reduction in chemical oxygen demand (COD) levels of 81.24 %, 74.14 %, 68.92 %, 60.24 %, and 53.82 %, respectively.

Simultaneous determination of pigments of spinach (Spinacia oleracea L.) leaf for quality inspection using hyperspectral imaging and multi-task deep learning regression approaches

Rapid and accurate determination of pigment content is important for quality inspection of spinach leaves during storage. This study aimed to use hyperspectral imaging at two spectral ranges (visible/near-infrared, VNIR: 400–1000 nm; NIR: 900–1700 nm) to simultaneously determine the pigment (chlorophyll a, chlorophyll b, total chlorophyll, and carotenoids) content in spinach stored at different durations and conditions (unpackaged and packaged). Partial least squares (PLS), back propagation neural network (BPNN) and convolutional neural network (CNN) were used to establish single-task and multi-task regression models. Single-task CNN (STCNN) models and multi-task CNN (MTCNN) models obtained better performances than the other models. The models using VNIR spectra were superior to those using NIR spectra. The overall results indicated that hyperspectral imaging with multi-task learning could predict the quality attributes of spinach simultaneously for spinach quality inspection under various storage conditions. This research will guide food quality inspection by simultaneously inspecting multiple quality attributes.

Synthesis of TiO2 nanoparticles using red spinach leaf extract (Amaranthus Tricolor L.) for photocatalytic of methylene blue degradation

ABSTRACT Textile industry waste such as methylene blue can pose a serious threat to health and ecosystems. One solution to overcome this problem is to utilize photocatalytic technology using TiO2 semiconductors. This research aims to make green synthetic TiO2 nanoparticles (NPs) using red spinach (Amaranthus Tricolor L.) leaf extract and used for photodegradation of methylene blue. Extraction of red spinach leaves showed that 30 min and a temperature of 95°C showed the highest phenolic content. In this research, several phenolic compounds were also identified in red spinach extract. For TiO2 NPs, the X-ray diffraction results show that TiO2 has a pure anatase phase. Electron microscope results show that TiO2 has the shape of agglomerated spherical clusters. The particle size distribution shows that TiO2 has an average size range of 77–90 nm. The methylene blue photodegradation showed that TiO2 had an efficiency of 90.36% for 180 min, higher than commercial TiO2 Evonic. This result can be attributed to the small particle size and broadband spectra so that photocatalysis is more effective.

Comparison Of The Effectiveness Of Moringa And Spinach Leaf Capsules In Increasing Hemoglobin Levels Among Anemic Pregnant Women In The Third

Background Data from the Bandar Lampung City Health Office in 2022 shows the proportion of anemia in pregnant women is 37.25%, namely pregnant women with Hemoglobin levels < 8 gr%/dl is 2.41%, Hb is 8-11gr%/dl is 36.3%. Anemia occurs in pregnant women due to insufficient production of red blood cells by the consumption of nutrients, especially iron. Iron can be obtained by consuming Moringa leaves. Another vegetable that is believed to contain a lot of iron is spinach, especially green spinach. The Purpose of the study was to find out the comparison of the effectiveness of moringa and spinach leaf capsules in increasing Hb levels in third trimester pregnant women with anemia in the Working Area of the Panjang Community Health Center, Bandar Lampung City, in 2023.Methods This study uses a type of quantitative research, with a quasi-experimental design. The population in this study were all pregnant women with their third trimester of gestation who made ANC visits at the Panjang Community Health Center in Bandar Lampung City and experienced anemia with a total of 47 people. A sample of 36 respondents. The data collection technique uses a questionnaire sheet and the data analysis used is the independent t-test.The results showed that the average hemoglobin level in third trimester pregnant women before consuming moringa leaf capsules was 10.46 gr/dl, and in the spinach leaf group was 10.37 gr/dl. The average hemoglobin level in third trimester pregnant women after consuming moringa leaf capsules was 11.87 gr/dl, and in the spinach leaf group was 11.24 gr/dl. Conclusion There is a difference in the effectiveness of moringa and spinach leaf capsules in increasing Hb levels in TM III pregnant women with anemia in the Working Area of the Panjang Community Health Center, Bandar Lampung City, 2023 (p value 0.000). Suggestion It is hoped that health workers can optimize counseling regarding the consumption of moringa leaf capsules to increase hemoglobin levels in third trimester pregnant women with anemia. Keywords: Moringa leaf capsules, spinach leaves, Hb levels

Nutritional, functional and sensory characteristics of an infant puree food from pre-treated pumpkin flesh (Curcubita pepo L.), soybean (Glycine max L.) and spinach leaves (Spinacia oleracea)

Complementary foods are essential during childhood. They permit and ensure growth and equally alleviate infant malnutrition. The use of locally available foods (Pumpkin, Soybean, and Spinach leaves) for the formulation of complementary foods is recommended as it could improve its accessibility. This study was aimed at formulating an infant puree food with good nutritional quality and an acceptable viscosity. Pumpkin, spinach leaves, and soybean were purchased from the central market of Ngaoundere and subjected to various treatments in the laboratory. Pumpkin flesh was fermented by Lactobacillus plantarum, spinach leaves were steamed, and soybean was soaked in water and latter roasted. The proximate composition of these foodstuff was determined before and after treatments. Two basic purees (PI and PII) were prepared from the pre-treated foods and five other formulations obtained from these basic purees were: (PI4, PI5, PII3, PII4, and PII5) thus corresponding to the addition of water at various volume percentages: 40, 50, 30, 40 and 50 respectively. The proximate composition and sensorial evaluation (taste, flavour, colour, smoothness, viscosity, appearance and overall acceptability) of theses purees were investigated. The results show that fermenting pumpkin flesh led to a significant (p < 0.05) increase in its soluble sugar content by 92.17 % while steam blanching increases the iron content in spinach leaves by 38.83 %. The viscosities of the derived purees produced were within 3280–4460 mPa s. All the formulated infant purees were poor in soluble sugar thus revealing that they all had a low energy value. This suggests that addition of sucrose during formulation could be required. Puree formulations PI4, PI5 and PII3 met the recommendations of WHO/FAO in terms of proteins (13.62 g/100g), fats (10.67 g/100g), and iron (10.00 mg/100g) content. We observed that the overall acceptability of formulated purees was significantly dependent on their taste and sugar content. Puree PII3 made of 85 % fermented pumpkin flesh, 7.5 % steamed spinach leaf paste, 7.5 % of soybean powder and 30 % of water by volume was the most appreciated by the panellists.

Analisis Fitokimia Terhadap Tepung Bayam (Amaranthus Viridis)

Various plants can be developed into traditional medicines and raw materials for making healthy food products because they contain bioactive compounds in the form of potential secondary metabolites. One plant that contains various potential secondary metabolites and can be developed as a health product is spinach. Green spinach leaf powder is reported to contain alkaloids, flavonoids, saponins, tannins, anthraquinones, steroids, coumarins, carotenoids, and phenols. This research aims to analyze the content of tannins, alkaloids, saponins, triterpenes, steroids, and flavonoids. Spinach flour is obtained by drying spinach leaves using a dehydrator for ± 19 hours at a temperature of 60 oC. The dried spinach leaves are ground with a blender until smooth, then sieved with a 70-mesh sieve. Phytochemical analysis was carried out qualitatively using color reagents. The research results showed that spinach flour contains bioactive compounds, namely tannins, alkaloids, triterpenes, and flavonoids. Spinach flour has the potential to be used as a raw material in the development of functional food products that are rich in potential bioactive compounds to improve public health

Comparative Evaluation of the Proximate, Phytochemical and Antioxidant Properties of Selected Leafy Vegetables (Bitter, Pumpkin and Spinach Leaves)

Comparative Evaluation of the Proximate, Phytochemical and Antioxidant Properties of Selected Leafy Vegetables (Bitter, Pumpkin and Spinach Leaves)

An Exploratory Analysis of the Stability and Quality of Instant Soup Mix Powder Incorporated with Malabar Spinach Leaves Powder under Refrigerated Conditions

The study was carried out for determining of the shelf life of the instant soup mix powder prepared using dried Malabar spinach leaves powder, tomato powder, moong dal powder and other main ingredients. Malabar spinach Instant soup mix powder formulated with 4 g of Malabar spinach leaves powder (MSLP), 20 g of moong dal powder (MDP), and 11 g of tomato powder (TP) along with other ingredients was liked extremely by 26.66 per cent of panel members, 60 per cent panellist liked it very much, and 13.33 per cent of panel members was liked it moderately after control treatment T0 (TP: MDP, 13:22g and 0g MSLP). The samples of instant soup mixes were packed into low density polyethylene (LDPE) and were analyzed periodically for change in quality. During 90 days of storage, there was a slight increase in the moisture content of the instant soup mix powder. In control instant soup mix powder (TP: MDP, 13:22g and 0g MSLP), moisture was initially 3.37 per cent which gradually increased to 3.46 per cent at the end of the period. The moisture content of the Malabar spinach instant soup mix powder for treatments T1, T2, T3, and T4 increased incrementally, following the same pattern. This finding was consistent across all treatments, indicating a clear trend. Total plate count indicates absence of microbial load during the storage period. The results of this investigation suggested that instant soup mixes could be kept in LDPE pouches at refrigerated temperature for ninety days without experiencing any quality deterioration.

Enhancing wound regeneration potential of fibroblasts using ascorbic acid-loaded decellularized baby spinach leaves

Decellularization of plant tissues is an emerging route to fabricate scaffolds for tissue engineering and regenerative medicine. Although significant progress has been made in the field of plant tissue decellularization, functionalization of plant scaffolds is still an emerging field, and loading them with L-ascorbic acid to promote skin regeneration has not yet been reported. L-ascorbic acid is an antioxidant that plays a key role in collagen synthesis as a cofactor of lysyl hydroxylase and prolyl hydroxylase. It has been shown to have significant importance in physiological wound healing by stimulating fibroblasts to produce collagen at both the molecular and the genetic levels. In this work, we aimed to fabricate an ascorbic acid-releasing bioactive scaffold by introducing a stable form of ascorbic acid, L-ascorbic acid 2-phosphate (AA2P), into decellularized baby spinach leaves and investigated its biological activity in vitro. Our results demonstrated that AA2P could be easily introduced into decellularized baby spinach leaf scaffolds and subsequently released within the effective dose range. AA2P-releasing baby spinach leaves were found to increase metabolic activity and enhance collagen synthesis in L929 fibroblasts after 21 days. In conclusion, this study demonstrated the fabrication of a novel functionalized skin tissue engineering scaffold and made a significant contribution to the fields of plant decellularization and skin tissue engineering.Graphical abstract

Impacts of sulfamethoxazole stress on vegetable growth and rhizosphere bacteria and the corresponding mitigation mechanism.

Antibiotics are an important pharmaceutical class excessively used by humans. Its presence in the soil can impact plant growth and induce antibiotic resistance. This research studies the effect of sulfamethoxazole (SMX) on plant growth, rhizosphere bacteria composition, and resistance genes. Two sets of vegetables (basil, cilantro, and spinach) were treated separately with water and SMX solution. The plant growth data and soil samples were collected and analyzed. The results revealed that SMX increased spinach leaf length (34.0%) while having no significant impacts on basil and cilantro. On the other hand, SMX improved the bacterial diversity in all samples. The shifts in the abundance of plant growth-promoting bacteria could indirectly affect vegetable stem and leaf length. SMX also significantly increased the abundance of resistance genes Sul1 and Sul2. A further study into the correlation between bacteria highlights the importance of Shingomonas and Alfipia for inhibiting the spread of key resistance gene hosts, namely, Pseudomonas, Stenotrophomonas, and Agrobacterium. This research provides insight into SMX's impact on vegetable growth and microbial diversity. It also points out important microbial interactions that could potentially be utilized to mitigate ARG proliferation.

PROXIMATE ANALYSIS OF SPINACH (Spinacia oleracea): NUTRITIONAL AND BUSINESS IMPLICATIONS

As the human population is rising, food demands are also surging up that can be met by cultivating wild vegetables, since they are considered low-cost food source among local populations. The current investigation during July 2023 to December 2023 is attempted, to quantitatively evaluate spinach (Spinacia oleracea), that is grown in Tagarapuvalasa, Visakhapatnam, Andhra Pradesh; India; for it is proximate composition levels and anti-microbial activity. Proteins, total carbohydrates and lipids were estimated by following Lowry et.al., [1951], Caroll et.al., [1956] and Bligh and Dyer [1959] respectively. The anti-microbial activity of the leaf extracts was determined by using the protocol reported by Shahriar et al. [2018b] and the zone of inhibition (ZOI) towards the microbes was calculated. From the results of this study, it was found that spinach of the study area is a significant source of macronutrients and micronutrients. Moreover, it also showed the highest anti-bacterial potential as observed in the results of the analysis. Hence, awareness regarding the nutritional and functional properties of these under-utilized leaves may aid towards nutritional and food security in addition to generating novel therapeutic avenues. It may be concluded that, apart from cultivating spinach during the main season, its yield 15 to 30 days early and later main season also may be a more profitable business, not only for a bigger farmer but also to small and marginal farmers. KEYWORDS: Spinach leaf extract, analysis, Nutrients, Anti-bacterial acitivity, Profit.

Mild and Efficient Extraction of Fluorescent Chlorophyll a from Spinach Leaves for Application as the Sustainable Emitter in Light‐Emitting Electrochemical Cells

AbstractNatural pigments are sustainable compounds that can be employed as emitters, sensors and sensitisers in optoelectronics. The most abundant pigment, chlorophyll, offers advantages of easily available and plentiful feedstock, biodegradability and non‐toxicity. However, strenuous extraction and separation limit its application on larger scale. In this work, a practically mild and scalable extraction and separation method for rapid isolation of chlorophyll a from spinach is presented. Three different stationary phases for column chromatography were evaluated, and a new solvent system was developed for the elution of chlorophyll a on a neutral alumina chromatography column. The purified product was obtained with a yield of 0.98 mg ⋅ g−1 with respect to the dry leaves. A first light‐emitting electrochemical cell (LEC) based on chlorophyll a as the emitter is reported, using the extracted chlorophyll a as the guest compound dispersed in a blend‐host matrix in a concentration of 2.5 or 5 mass %. The higher‐chlorophyll‐concentration LEC exhibits emission solely from the chlorophyll emitter, with the main emission peak located at 675 nm. The lower‐chlorophyll‐concentration LEC features two distinct emission bands, one in the red region that is originating from the chlorophyll guest and one in the blue region (main peak at 430 nm) that stems from the blend host. This combined red:blue emission can be attractive for, e. g., greenhouse applications, since it matches the action spectrum of plant photosynthesis.