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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
101

Caracterização físico-química e capacidade antioxidante do butiá. / Physico-chemical characteriazation and antioxidant capacity of pindo palm.

Sganzeria, Marla 04 February 2010 (has links)
Made available in DSpace on 2014-08-20T13:42:09Z (GMT). No. of bitstreams: 1 Dissertacao_Marla_Sganzeria.pdf: 1113012 bytes, checksum: b547757cc00a9c95681ca740a58161e0 (MD5) Previous issue date: 2010-02-04 / The species belonging to the Palmae (Aracaceae) family are distinguished by the natural and economic resource that they represent to human populations as its ecological role in the vegetation. In Rio Grande do Sul there are six genera of native palm trees, among them occurs the palm Butia genus, mainly the species of B. capitata and B. eriospatha, which produce fruits that are consumed as raw or as byproducts same as juice, liqueur and ice cream. The interest in native species and small fruit is growing in recent years due to the benefit that they can provide to human health, due to the action of compounds derived from the secondary metabolism of plants. Thus, this study aimed to characterize the fruits of B. capitata and B. eriosphata species, determining the nutritional composition, the presence of the phytochemical compounds and the antioxidant capacity of the pulp and kernel fractions. In relation to biometry, pindo palm fruits of both species presented a flat shape due to higher measures of diameter compared with measures of length, besides high-yield pulp (70.97% for B. capitata); the peel color of fruits from both species of pindo palms are located within the first quadrant between the shades of red and yellow. The almond fruits composition stand out levels of fiber and carbohydrates, and also the caloric content of 392.18 kcal.100g-1 and 358.03 kcal.100g-1 (B. capitata and B. eriosphata species, respectively), due to high fat content, which is a good indicator for the extraction of oil, that is rich in medium chain fatty acids (C6-C12), achieving 56.48% for the species of B. capitata and 43.70% for the species of B. eriosphata. Among the phytochemical compounds, highlights the concentration of total phenols, 416.73mg GAE.100g-1 and 443.1973mg GAE.100g-1 in almonds of B. capitata and B. eriosphata species, respectively, and the absence of tocopherols in the almonds of the species evaluated. In relation to the fruit pulp, there was strong positive correlation between soluble solids and total sugars for B. capitata specie (0.990), while for the species B. eriosphata the most significant correlation occurred between soluble solids and acidity content (0.994). The total caloric value was equivalent to 53.21 kcal.100g-1 for B. capitata specie and 42.30 kcal.100g-1 for B. eriosphata specie, mainly due to the carbohydrate content. The fiber content in species of B. capitata (1.22%) and B. eriosphata (0.88%) were lower than the values reported for the fruits from other palm species. Through principal component analysis, considering the physical-chemical composition and the antioxidant activity was possible to differentiate these two species of pindo palm. In the phytochemical composition of pindo palm fruit included the concentration of phenols, vitamin C, which correlated with antioxidant capacity, and the carotenoid content. / As espécies pertencentes à família Palmae (Aracaceae) destacam-se tanto pelo recurso natural e econômico que representam às populações humanas, como pelo seu papel ecológico nas formações vegetais. No Rio Grande do Sul ocorrem seis gêneros de palmeiras nativas, entre eles, destacam-se as palmeiras do gênero Butia, principalmente as espécies: B. capitata e B. eriospatha, que produzem frutos que são consumidos in natura ou utilizados para o preparo de sucos, licores e sorvetes. O interesse pelas espécies nativas e pequenos frutos vem crescendo nos últimos anos devido ao benefício que podem proporcionar à saúde humana, devido a ação de compostos oriundos do metabolismo secundário das plantas. Assim, este estudo teve como objetivo caracterizar os frutos de butiá das espécies B. capitata e B. eriosphata, determinando a composição nutricional, a presença de compostos fitoquímicos e a capacidade antioxidante das frações polpa e amêndoa. Quanto à biometria, os frutos de butiá apresentaram-se com forma achatada devido às maiores medidas de diâmetro comparado as medidas de comprimento, com elevado rendimento de polpa (70,97% para a espécie B. capitata); os valores de cor da epiderme dos frutos de ambas as espécies de butiás se localizaram dentro do primeiro quadrante entre as tonalidades de vermelho e amarelo. Na composição da amêndoa dos frutos destacam-se os teores de fibras e de carboidratos e também no valor calórico 392,18Kcal.100g-1 e 358,03Kcal.100g-1 (espécies B. capitata e B. eriosphata, respectivamente), devido ao elevado teor de lipídios, o que consiste em um bom indicativo para extração de óleo, cuja composição é rica em ácidos graxos de cadeia média (C6-C12), perfazendo 56,48% para a espécie B. capitata e de 43,70% para a espécie B. eriosphata. Dentre os fitoquímicos destaca-se o teor de fenóis totais de 416,73mg GAE.100g-1 nas amêndoas das espécies B. capitata e de 443,19mg GAE.100g-1 para a espécie B. eriosphata e a ausência de tocoferóis nas amêndoas de ambas as espécies. Em relação à polpa dos frutos, observou-se correlação positiva forte entre teor de sólidos solúveis e de açúcares totais para butiás da espécie B. capitata (0,990), enquanto que para a espécie B.eriosphata a correlação de maior significância ocorreu entre teor de sólidos solúveis e de acidez (0,994). O valor calórico total foi equivalente a 53,21 Kcal.100g-1 para a espécie B. capitata e de 42,30 Kcal.100g-1 na espécie B. eriosphata, decorrentes principalmente do teor de carboidratos. Os teores de fibra bruta nas espécies B. capitata (1,22%) e B. eriosphata (0,88%) foram inferiores aos valores reportados para outras espécies pertencentes à família Palmae. Através da análise de componentes principais, considerando a caracterização físico-química e capacidade antioxidante foi possível diferenciar as duas espécies de butiás. Na composição fitoquímica de frutos de butiás destacam-se os teores de fenóis e de vitamina C, que se correlacionaram com a capacidade antioxidante, além do conteúdo de carotenóides.
102

Plant adaptation and enhancement of phytochemicals in lettuce in response to environmental stresses

Oh, Myungmin January 1900 (has links)
Doctor of Philosophy / Department of Horticulture, Forestry, and Recreation Resources / Channa B. Rajashekar / Studies were conducted to examine the role of antioxidants in adaptation of lettuce (Lactuca sativa L.) to unprotected environmental conditions and various environmental stresses. Antioxidants, in addition to being a plant defense mechanism, are phytochemicals that provide significant health-promoting and nutritive value in human diet. Various approaches involving mild environmental stresses and cultural and management practices have been used to enhance the quality of this commonly consumed leafy vegetable by improving its phytochemical and health-promoting attributes. Lettuce plants grown in protective environments adapt to unprotective environmental conditions by activating antioxidant genes such as phenylalanine ammonia-lyase (PAL), gamma-tocopherol methyl transferase (gamma-TMT), and L-galactose dehydrogenase (L-GalDH) involved in the biosynthesis of phenolic compounds,alpha-tocopherol and ascorbic acid, respectively. Mild environmental stresses such as heat shock, chilling, water stress and high light also activate these genes leading to the accumulation of secondary metabolites and phytochemicals without any adverse effect on biomass accumulation. The phytochemicals included chlorogenic acid, chicoric acid, caffeic acid, quercetin-3-O-glucoside and luteolin-7-O-glucoside. However, under field conditions, application of drought stress did not produce consistent results with regard to the phytochemical composition of lettuce. Plants grown in open field have higher phenolic content and higher antioxidant capacity than those grown in high tunnel. However, these plants also had less biomass accumulation. Many factors such as plant age, variety, fertilization, transplanting shock affected the phytochemical composition of lettuce. The red leaf variety 'Red Sails' had higher antioxidant capacity than 'Baronet' and younger plants had the highest phytochemical content. With regard to the management practices, there was no significant difference in phytochemical composition between organically and conventionally managed crops. Also, low fertility favored the accumulation of phytochemicals and increased the antioxidant capacity. Thus, the results show that mild environmental stresses along with appropriate cultural and management practices can enhance the quality of lettuce by improving their phytochemical composition.
103

Comparative phytochemical analyses of Aloe Ferox Mill. found in Eastern and Western Cape provinces in South Africa

Adams, Zanele January 2013 (has links)
No description available.
104

Evaluation of the efficacy of Carpobrotus edulis (L.) bolus leaf as a traditional treatment for the management of HIV/AIDS

Omoruyi, Beauty Etinosa January 2014 (has links)
The human immunodeficiency virus (HIV) is one of the most common and dreaded diseases of the 21th century. Today, the disease is still spreading with increasing incidence. “Since the beginning of the epidemic, almost 75 million people have been infected with the HIV virus and about 36 million people have died of HIV. Globally, 35.3 million [32.2–38.8 million] people were living with HIV at the end of 2012” (http://www.who.int/gho/hiv/en/). Several studies have been conducted on herbs under a multitude of ethnobotanical grounds. The use of medicinal plants for the management of HIV has become a common practice especially, in the Eastern Cape Province of South Africa (Wilfred Otang Mbeng, 2013 PhD thesis, UFH). At the beginning of this programme, an ethnomedicinal survey of plants used for the management of HIV infection was carried out in targeted areas of the Province and information on the names of plants, the parts and the methods of preparation were collected. The survey revealed that 18 species representing 12 families were found to be commonly used for the management of HIV, as well as other opportunistic diseases such as tuberculosis, diabetes mellitus, sores, high blood pressure, etc. Carpobrotus edulis was selected for this research because it was the most frequently used in the Province. The foliar micro morphological contents of the plant, its phytochemical and antioxidant activity, in vitro antimicrobial activity, inhibitory effect against HIV-1 protease and reverse transcriptase, mechanisms of action and cytotoxicity were investigated. In terms of the foliar micro morphological contents in plants, an electron microscopy scanning (SEM) was completed. Investigation revealed that both glandular tricomes and calcium oxalate crystals (CaOX) were observed. Consequently, it is hypothesized that the bioactive therapeutic compounds secreted by C. edulis may be produced in the glandular trichomes. An investigation of phytochemical content of the plant extracts (C. edulis) was completed using four solvent extracts (hexane, acetone, ethanol and water). Results of the phytochemical analysis showed that proanthocyanidins (86.9 ± 0.005%) where highest in the aqueous extract with phenolics at 55.7 ± 0.404% in acetone extract, tannin at 48.9 ± 0.28% in ethanol extract, while the hexane extract had the highest levels of flavonoids (0.12 ± 0.05%) and flavonols (0.12 ± 0.05%). Antioxidant studies of the various extracts revealed that aqueous and ethanol extracts were found to be the best solvents for antioxidant activity in C. edulis leaves. GC-MS analysis of the essential oil from C. edulis leaves revealed that the essential oil contained at least 28 compounds. These included, in order of abundance: Oxygenated monoterpenes (36.61%); fatty acids esters (19.25%); oxygenated diterpenes (19.24%); monoterpenes (10.6%); sesquiterpenes (3.58%); and diterpenes (1.43%). Similarly, a GC-MS analysis of the crude hexane, acetone and ethanol extracts from C. edulis leaves identified a total of 59 compounds. Of the 59 compounds, 12 major phyto-metabolites that are active against infectious diseases were identified. To comfirm the potential use of C. edulis to treat infectious disease, antifungal activity of the crude essential oil extract and the four solvent extracts were tested against Candida albicans, Candida krusei, Candida glabrata, Candida rugosa and Cryptococcus neoformans strains. The essential oil extract was found to be the most active against all the fungal strains tested and performed better than the four extracts used various solvents used to extract (hexane, acetone, ethanol and water) the C. edulis leaves were tested for antibacterial and anti HIV-1 reverse transcriptase (RT) activity. The results indicated that both gram-positive and gram-negative isolates were inhibited by the extracts (hexane, acetone and ethanol) but antimicrobial activity was observed for the water extract. The lowest minimum inhibitory concentration values were obtained for the ethanol extract, followed by acetone and hexane extracts. No inhibition of HIV-1 reverse transcriptase was observed for any of the leaf extracts, even up to concentrations of 16 mg/ml. The potential inhibitory activities of the various solvent extracts against HIV-1 protease were evaluated at four different concentrations (16, 1.6, 0.16 and 0.016 mg/ml). Results indicated that the water extract showed almost 100% inhibition of HIV-1 protease activity, with an IC50 of 0.86 mg/ml leaf extract. Other solvent extracts (hexane, acetone and ethanol) however, did not show any inhibition activity above that observed for the DMSO control. The metabolic components in the water extract were subjected to LC-MS/MS analysis, which identified at least 91 compounds present in the water extract. Further studies involving the molecular modelling need to be carried out to confirm the inhibitory potential of these compounds. The cytotoxicity of the water extract of C. edulis leaves was also screened using human Chang liver cells at concentrations ranging bewteen 0.005 mg/ml and 1 mg/ml. Results indicated that the water extracts were not toxic. In conclusion the results from this study support the use of water extracts of C. edulis leaves by traditional healers to treat HIV infections and have identified possible mechanisms of action of the water extracts of C. edulis.
105

Phytochemical screening and thin layer chromatographic profiling of aloe vera (l) burn. f growing in South Africa

Dubeni, Zimasa Busisiwe January 2013 (has links)
The chemical profiling, characterization of Aloe products and phytochemical properties of Aloe vera were studied. The adulteration of commercial products derived from medicinal plants has been a major muddle for both the society and the pharmaceuticalindustry. Economically motivated adulteration includes the potential for contaminated, sub‐potent or counterfeit medication to enter the supply chain at several levels, from the production of raw ingredients through to the point of retail sale. Darwin’s theory of evolution states that, species undergo genetic variation with time to adapt to environmental changes. Therefore, the same species growing in widely different habitats may drift from the original genetic makeup as a mechanism of adaptation and that may result in them having different chemical profiles. Therefore this study aimed at investigating the phytochemical properties of Aloe vera growing in South Africa. Also, this study aims to utilize Thin Layer Chromatography to profile this plant, as well as use Infra Red spectroscopy to characterize commercial Aloe vera products. A large quantity of Aloe vera plant was collected from AloeWay, Iphofolo Game Farm, Polokwane in the Limpopo province of South Africa. The identity of the plant was confirmedrom literature and authenticated by Professor DS Grierson of Botany Department, University of Fort Hare, Alice. The plant leaves were divided into two portions. One portion was extracted fresh while the other was cut into pieces and oven dried at 400C then and milled to a homogenous powder once dried completely. The phytochemical composition of the gel and leaf extracts revealed the presence of alkaloids, flavonoids, saponins, tannins and phenols at different concentrations. Results showed that the dry plant material yielded more phytochemicals than the fresh plant material. In particular, it was found that the acetone extract showed much more amounts ofphychemicals than the dichloromethane and aqueous extracts. The percentage compositions of phenols (71.86), flavonols (36.61), proanthocyanidins (82.71), saponins (37.73) and alkaloids (13.29) were significantly high in the acetone extract, followed by the dichloromthane extract with values of 46.85, 37.73, 49.51, 89.0 and 11.11 respectively, while the least composition was found in the aqueous extract. Furthermore, flavonoids were somewhat high in composition in both the aqueous extract of the dried and of the fresh plant material while others were very low. Tannins levels were significantly very low in all the solvent extracts. It was found that the acetone extract showed great amounts of phytochemicals than dichloromethane and aqueous extracts. Since A. vera is used in the treatment of different ailments such as skin wounds and abrasions, eczema, constipation, rheumatoid arthritis etc, the medicinal uses of this plant could be associated to such analysed bioactive compounds. Acetone, hexane, ethanol, water and dichloromethane were used to extract the Aloe vera leaf and the best solvent extract was determined. Thin layer chromatography was used to profile the leaf extracts with the aim of documenting the main phytochemicals present in the Aloe vera growing in South Africa. The best spraying reagent was determined. Fourier transform infrared spectrophotometer was used to validate the presence of Aloe vera ingredients in commercial products. The yield extraction ability of the solvent was the order: water>ethanol> hexane >dichloromethane and acetone for the dry portion. However, for the plant extracted fresh, the order of yield produced was ethanol-acetone-dichloromethane > and water. The different solvent systems separated the compounds differently. Hexane: acetone: ethanol (20 : 5: 2) and Benzene: ethanol: ammonium (80): ethanol (10): ammonium solvent systems were noted to be the best mobile phase as they gave the best separation compared to other systems.EMW [ethyl acetate (81): methanol (11): water (8)] showed better separation than the other two separating solvent systems. Vanillin- sulphuric acid spray was seen to be the best spraying reagent as compared to vanillin- phosphoric acid. Fourier transform infrared spectrophotometer validated the presence aloe ingredients in aloe vera commercial products.
106

Atividade antiproliferativa de extrato de araucaria angustifolia em células tumorais de laringe HEp-2

Branco, Cátia dos Santos 02 December 2016 (has links)
Os produtos naturais constituem uma das fontes mais promissoras para o descobrimento de novos ativos na terapêutica do câncer. O carcinoma de laringe é um dos mais comuns tipos de câncer envolvendo as áreas de cabeça e pescoço, e apresenta elevada taxa de morbidade e mortalidade em pacientes com estágio avançado. Terapias alternativas e/ou adjuvantes para o tratamento deste tipo de câncer representam uma necessidade emergente. Uma das alternativas mais promissoras é o desenvolvimento de nanocarreadores contendo ativos antitumorais. Araucaria angustifolia (Bert. O Kuntze) pertence à família Araucariaceae e é uma planta reconhecidamente medicinal. Seus estróbilos femininos dão origem a pinha, constituída por pinhões (sementes verdadeiras) e brácteas (sementes não desenvolvidas). O objetivo do presente estudo foi avaliar o efeito antiproliferativo do extrato aquoso de brácteas de A. angustifolia (EAA) em células tumorais de laringe HEp-2 e seus mecanismos de ação. Além disso, a possibilidade de associar o EAA a nanoesferas (NE) a fim de potencializar seu efeito antitumoral também foi investigado. A análise química por meio de Espectrometria de Massas de Alta Resolução evidenciou a presença majoritária de polifenóis no EAA. Os resultados mostraram que o EAA induziu citotoxicidade nas células tumorais HEp-2 através de dois diferentes ensaios de viabilidade celular (ensaio de MTT e de exclusão do corante Trypan blue). No entanto, o mesmo não foi capaz de induzir citotoxicidade significativa em células normais HEK-293, utilizadas como controle, indicando um efeito diferencial seletivo do EAA sobre as células tumorais. As células HEp-2 tratadas com EAA apresentaram níveis aumentados de peroxidação lipídica, danos oxidativos a proteínas e aumento da produção de ON, juntamente com depleção das defesas antioxidantes superóxido dismutase (Sod) e catalase (Cat). Além disso, o EAA induziu danos ao DNA, juntamente com fragmentação nuclear e condensação da cromatina nestas células. Alterações nos marcadores epigenéticos, como hipometilação do DNA e redução da atividade de DNMT1 foram também observadas. A exposição das células tumorais ao extrato aumentou a expressão de proteínas apoptóticas de via intrínseca mitocondrial, mediada pela ativação da proteína Bax, liberação de AIF e foi independente da ativação de p53. O EAA modificou o metabolismo energético das células tumorais, elevando os níveis de piruvato desidrogenase (PDH) e estimulando a fosforilação oxidativa mitocondrial. Embora tenha ativado a mitocôndria destas células, o mesmo causou falhas no potencial de membrana mitocondrial (ΔΨm), juntamente com diminuição dos níveis de proteínas dos complexos I e III da CTE, inibição da atividade do complexo I, produção de ERO e depleção de ATP. A associação do EAA à NE permitiu a obtenção de sistemas com tamanho de partícula inferior a 200 nm, índice de polidispersibilidade abaixo de 1, potencial zeta negativo e pH estável pelo período de 30 dias, na condição testada. No entanto, a taxa de associação obtida foi baixa (19%), indicando a necessidade de futuros estudos a fim de aumentar a eficiência de incorporação do extrato. As NE per se demonstaram capacidade de reduzir a viabilidade de células tumorais e induzir alterações redox, sensibilizando estas células, demonstrando ser um possível carreador para a vetorização de ativos antitumorais. O conjunto de dados deste estudo demonstra a potencialidade dos compostos presentes nas brácteas de A. angustifolia para o desenvolvimento de novas estratégicas terapêuticas para o câncer. / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior, CAPES. / Natural products are among one of the most promising fields in finding new active substances in cancer therapy. Laryngeal carcinoma is one of the most common cancers affecting the head and neck regions, and is associated with high morbidity and mortality in patients with the advanced stage. Alternative and/or complementary therapies for treating this cancer represents an emerging need. One of the most promising alternatives is the development of nanocarriers containing antitumor substances. Araucaria angustifolia (Bert. O Kuntze) belongs to Araucariaceae family and it is recognized as medicinal plant. Female strobilus originates the pinecone, which contains seeds and undeveloped seeds, commonly known as bracts. The aim of this study was to evaluate the antiproliferative effects of A. angustifolia bracts aqueous extract (AAE) in HEp-2 cancer cells and its action mechanisms. Moreover, the possibility to associate AAE in nanospheres (NS) to improve its antitumor effect was also investigated. Chemical analysis using High Resolution Mass Spectrometry (HRMS) revealed the major presence of polyphenols in AAE. The results showed that AAE induced cytotoxicity in HEp-2 cells, by using two differents approaches (MTT and Trypan blue assays). However, the extract was not able to induce significant cytotoxicity in HEK-293 normal cells used as control, indicating a selective differential effect of AEE in tumor cells. HEp-2 treated cells presented high levels of lipid peroxidation, oxidative damage to proteins and increment on NO production, along with depletion on antioxidante defenses superoxide dismutase (Sod) and catalase (Cat). In addition, AAE induced DNA damage, nuclear fragmentation and chromatin condensation in these cells. Epigenetic alterations, such as DNA hypomethylation and DNMT1 activity were also observed. Cell exposition to the AAE increased expression of proteins of the mitochondrial intrinsic pathway, via Baxtriggered, along with AIF release, and it is independent of p53 incitement. AAE changed energetic metabolism of cancer cells, increasing levels of pyruvate dehydrogenase (PDH) and stimulating mitochondrial oxidative phosphorylation. Although it enabled the mitochondria of these cells, the extract caused loss of mitochondrial membrane potential (ΔΨm), reduction on protein expression levels of complex I and III, inhibition of complex I activity, ROS generation and ATP depletion. The association of EAA to NS allowed obtaining systems with particle size lower than 200 nm, polydispersity index less than 1, negative zeta potential and pH stable for the period of 30 days, under tested condition. However, the association rate obtained was low (19%); therefore, further studies are needed to improve AAE encapsulation. The NS per se demonstrated ability to reduce the viability of tumor cells and induce redox stress, sensitizing these cells, proving to be a possible carrier for delivery of antitumor substances. The data set of this study demonstrates the potentiality of the compounds present in the A. angustifolia bracts for the development of new therapeutic strategies for cancer.
107

Exploring metabolic and genetic diversity in tomato secondary metabolites

Dzakovich, Michael Paul January 2020 (has links)
No description available.
108

Miscibility, Morphology and Biocompatibility Studies of Novel Hemodialysis Membranes with Enhanced Anti-oxidant and Anti-inflammatory Properties

Chandrasekaran, Neelakandan 05 August 2010 (has links)
No description available.
109

Functional diversity of indigenous diets in coastal Papua New Guinea : role in the nutrition transition and noncommunicable disease risk

Owen, Patrick. January 2008 (has links)
No description available.
110

The chemical composition of baby spinach (Spinacia oleracea L,) as affected by nitrogen, phosphorus and potassium nutrition

Zikalala, Bongekile Octavia 01 June 2015 (has links)
Baby spinach (Spinacia oleracea L.) is considered to be the one of the extremely nutritious vegetables, rich both in phytochemicals and core nutrients. Nowadays, phytochemicals in plants are raising interest in consumers for their roles in the maintenance of human health. Variation in content of bioactive compounds and core nutrients is the main concern in vegetable production. Factors such as cultural practices specially fertilization, may affect the nutritional and medicinal properties of the plants Therefore, three parallel trials for NPK to investigate the response of baby spinach leaves to nitrogen (N), phosphorus (P) and potassium (K) on chemical composition were conducted, with treatments arranged as follows: 0, 45, 75, 105, 120 kg·ha-1 N and P and 0, 60, 85, 106, 127, 148 kg·ha-1 K in a randomized complete block design (RCBD) with four replications. The results demonstrated that, application of nitrogenous, phosphorus, potassium fertilizers significantly increased the total phenolic content, total antioxidant activity, total flavonoid content and vitamin C while magnesium, iron, zinc and selenium did not exhibit significant response to all treatments applied. The increase in concentrations on total phenolic content, total antioxidant activity, total flavonoid content and vitamin C was observed, reaching maximum at 45 kg·ha-1 N, 75 kg·ha-1 P and 85 kg·ha-1 K. The optimum rates of 45 kg·ha-1 N, 75 kg·ha-1 P, 85 kg·ha−1 K were then used to formulate the NPK treatment combinations as follows: 0, 30: 30: 40, 45:45:60, 60:60:70, 75:75:90 kg·ha-1, arranged in a RCBD with three replicates. The results showed that total phenolic content, total antioxidant activity , total flavonoid content and vitamin C reached maximum in baby spinach leaves at N45:P45:K60 kg·ha-1 / Agriculture,  Animal Health & Human Ecology / M.Sc. (Agriculture)

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