Spinach Extract Research Articles

Effect of hexane extract of spinach in the removal of arsenic from rat

Extensive search is going on for a cheap, easily available and effective remedy of chronic arsenic poisoning. The present study was designed to find the effects of hexane extract of spinach in the removal of arsenic from arsenic treated rat. Rats were fed arsenic trioxide through Ryle’s tube for one month then they were fed on hexane extract (1-4%) of spinach for another one month. Hexane extract of spinach decreased accumulated arsenic from rat liver, spleen, kidney, intestine, lungs and skin significantly. Besides, it reduced the oxidative stress caused by arsenic which was evident by decreased levels of malondialdehyde (MDA) in the above tissues. Hexane extract decreases both arsenic level and MDA level in rat tissues in dose dependent manner, which is more effective at lower doses.

<i>Spinacia oleracea</i> modulates radiation-induced biochemical changes in mice testis

The present study is an attempt to investigate the radioprotective efficacy of spinach against radiation induced oxidative stress, since its leaves are rich in antioxidants like carotenoids (β-carotene, lutein and zeaxanthin) and high content of proteins, minerals, vitamin C. For the experimental study, healthy Swiss mice were selected from an inbred colony and divided into four groups. Group I (normal) it did not receive any treatment. Group II (drug treated) was orally supplemented with extract of spinach extract once daily at the dose of 1100 mg/kg for fifteen consecutive days. Group III (control) received distilled water orally equivalent to spinach extract for fifteen days than exposed to 5 Gy of gamma radiation. Group IV (experimental) was also administered orally with spinach extract for 15 consecutive days once daily. Thereafter, exposed to single dose of 5Gy of gamma radiation. After the exposure mice were than sacrificed at different autopsy intervals viz. 1, 3, 7, 15 and 30 days. Testis was removed for various biochemical estimations viz. LPO, protein, cholesterol and glycogen. Radiation induced augmentation in lipid peroxidation, glycogen and cholesterol values were significantly ameliorated by supplementation of SE extract, whereas radiation induced deficit in protein content could be elevated. This indicates that spinach extract pre - treatment renders protection against various biochemical changes in the mice testis to some extent if taken continuously which might be due to synergistic effect of antioxidant constituents present in the spinach.

Stability of anthocyanin in spinach vine (Basella rubra) fruits

E. Ferreira Ozela, P. Cesar Stringheta, and M. Cano Chauca. 2007. Stability of anthocyanin in spinach vine (Basella rubra) fruits. Cien. Inv. Agr 34(2):115-120. The stability of anthocyanin in the extract of spinach vine fruit (Basella rubra L.) was studied in relation to degradative factors such as light, temperature and pH acting alone or in combination. In this work, the possible use of spinach vine fruit as a source of natural pigments for use in food coloring was evaluated. Extraction of the pigment was carried out with 99.9% methanol at pH 2.0. The stability of the anthocyanin extract was estimated. From these values, reaction velocity constants (k) as well as the half-life time (t1/2) were calculated at pH 4.0, 5.0, and 6.0 in the presence and absence of light both at 40 and 60oC. Results indicate that, independent of pH values, spinach vine extract suffered an interference of light in its anthocyanin degradation kinetics with the mean t1/2 being greater in samples place in darkness (654.5 ± 66.6 h) compared to exposed to light (280 ± 60.62 h). In the presence of light, degradation of the anthocyanin pigment increased with increased temperature and had an average half life time of 280 ± 60.62 h, 6.88 ± 0.76 h and 2.42 ± 0.31 h at room temperature (25 ± 1oC), 40 and 60oC, respectively. Spinach vine extract was more stable at pH 5.0 and 6.0 than at pH 4.0 both in the presence and absence of light. This characteristic differs from other anthocyanins. This property could facilitate its application as a natural food colorant.

Application of high-speed counter-current chromatography for the isolation of 9′- cis-neoxanthin from fresh spinach

Preparative HSCCC (high-speed counter-current chromatography) could be applied for the isolation of 9′- cis-neoxanthin from a crude carotenoid extract of fresh spinach leaves. The separation was performed on a Pharma-Tech Research Corp. CCC 1000 with a solvent system composed of hexane:ethanol:water at a volume ratio of 5:5:4.5 at a flow rate of 3 mL/min and at 850 rpm, using the lower phase as mobile phase. 9′- cis-neoxanthin with a purity of up to 94% could be obtained with a single HSCCC purification step of the crude carotenoid extract.

Evaluation of antioxidant capacity of some fruit and vegetable foods: efficiency of extraction of a sequence of solvents

AbstractAll methods for assessing the total antioxidant capacity (TAC) of food samples are strongly affected by the solvents used during extraction. In recent years a sequential solvent extraction procedure utilising water and acetone has been widely used for TAC measurements of foods. To better understand the efficiency of this procedure in terms of the amount of extracted antioxidants and the subsequent measurement of TAC, two vegetables (onion and spinach) and two fruits (orange and tomato) were sequentially extracted with water, acetone and chloroform. Each extract fraction was analysed separately for its content of known antioxidant compounds by specific procedures and for its TAC by the Trolox equivalent antioxidant capacity assay. The results showed that the compounds in the water and acetone extracts were the main contributors to TAC. The chloroform extracts did not contribute to TAC, with the exception of the spinach extract, owing to the presence of low levels of carotenoids. In conclusion, the analysed extraction procedure was more effective for foods rich in water‐soluble antioxidants than for those rich in lipid‐soluble antioxidants. Copyright © 2006 Society of Chemical Industry

Capacidade antioxidante de hortaliças usualmente consumidas

This study was carried out to determine the antioxidant capacity of 15 vegetables commonly consumed in Recife - PE, Brazil. Methanol extracts were screened for their antioxidant activity using two tests: DPPH free radical scavenging and b-carotene/linoleico acid assay. All vegetables showed antioxidant properties however the action was differentiated among the kinds of vegetables. The methanol extracts of collard greens, tomatoes, potatoes, cauliflowers, green cabbage, spinach and lettuce crespa had the highest percentage in terms of free radical scavenging activities (> 70%). A moderate activity (60-70%) was shown by lettuce lisa, white onion and green beans while purple onion, chayote, cucumber and carrot had the lowest free radical scavenging activities. In the b-carotene/linoleic acid assay, spinach and collard greens extracts showed strong antioxidant activity (> 70%). The lettuce lisa, white onion and cauliflower had a moderate action (60-70%) while the chayote, carrot, cucumber, tomato and green bean showed weak antioxidant activity. The results indicate that vegetables which were evaluated may provide a source of dietary antioxidant therefore their consumption must be encouraged.

Description of a Novel Panallergen of Cross-Reactivity between Moulds and Foods

The present investigation is undertaken to demonstrate a novel cross-reactivity between aeroallergens (moulds fungi imperfecti) and allergens from foods (spinach and mushroom Agaricus bisporus). We have performed a dual study in vivo and in vitro, in a population of atopic patients. Data from in vivo tests performed with spinach and mushroom have been statistically analysed. To the in vitro assays, mushroom and spinach extracts have been obtained, and sera from moulds allergic patients analysed by means of IgE–immunoblott assays. Inhibition experiments have been also performed to study a possible relation between proteins. Statistical analysis of data showed a relation between allergenicity to moulds (Alternaria alternata, Cladosporium herbarum and/or Aspergillus fumigatus), and positive skin prick tests with mushroom and/or spinach. The immunoblotts performed showed that seven moulds allergic patients had a strong recognition of a protein with a molecular weight of about 30 kD present both in spinach and mushroom extracts, and by means of inhibition assays we could determine that these two proteins were related. This study demonstrates the existence of a new allergen responsible for cross reactivity between moulds and two frequently consumed foods, mushroom and spinach. We conclude that a novel cross-reactive allergen between aeroallergens and foods has been identified.

Differential attenuation of oxidative/nitrosative injuries in early prostatic neoplastic lesions in TRAMP mice by dietary antioxidants

Dietary antioxidants with yet unproven efficacies in averting prostate cancer (PCa) are widely used in the United States as preventives. Experimental evidence establishing a causal relationship between oxidative and nitrosative stress (OS/NS) and PCa development and showing its modulation by dietary antioxidants would help justify their usage. The TRAMP (Transgenic Adenocarcinoma of the Mouse Prostate) mouse model was used to demonstrate the OS/NS-associated damage, as evident by 8-hydroxy-2'-deoxyguanosine (8-OHdG), 4-hydroxynonenal (4-HNE)-protein-adducts and nitrotyrosine (Ntyr), in prostatic premalignant lesions, and to evaluate the antioxidant efficacy of various dietary supplements [natural antioxidant (NAO) from spinach extracts, (-) epigallocatechin-3-gallate (EGCG), or N-acetylcystein (NAC)] during the early PCa development. We show, for the first time, that oxidative/nitrosative damages of genomic DNA and cellular proteins were discretely localized in premalignant lesions, but not in adjacent morphologically normal epithelia, of TRAMP prostates; these injuries were absent in age-matched nontransgenic littermates. The extent of OS/NS-related injuries correlated well with the tempo of development and prevalence of premalignant lesions in various prostatic lobes and exhibited a clear trend of increase from 12 to 20 weeks of age. Treatment of TRAMP mice with various antioxidants as dietary supplements resulted in differential alleviation of OS/NS-related prostatic injuries. The antioxidant potencies of the dietary supplements did not fully correlate with their documented antiPCa actions, suggest that they may exert additional "nonantioxidant," antitumor effects in this model. Our data indicate that in TRAMP mice, OS/NS injuries are likely involved in early prostatic tumorigenesis and can be modulated by various antioxidants.

Antioxidant and antiproliferative activities of water spinach (Ipomoea aquatica Forsk) constituents

The aim of this study was to examine possible antioxidant and antiproliferative activities of 95% ethanol or water extract from water spinach (Ipomoea aquatica Forsk) organs. DPPH staining, total phenolic compounds, total flavonoid content, DPPH radical, reducing power method, FTC method, and inhibition of cancer cell prolifera- tion were employed. Ethanol extract of stem demonstrated a positive effect in DPPH staining when it was diluted to 6.25 mg dry matter/mL while all other fractions showed no effect at the same dilution. This fraction also had the highest content of the total phenolic compounds, as well as the highest reducing power and FTC activity. Ethanol extract of leaf had the highest amount of flavonoids. Using DPPH colorimetric method, it was found that ethanol extract of stem had the highest radical-scavenging activity, followed by ethanol extract of leaf. The antiproliferative activities of water spinach extracts were studied in vitro using human lymphoma NB4 cells, and the following results were found: water extract of stem had the highest antiproliferative activity with an EC 50 of 661.40 ± 3.36 µg dry matter/mL, followed by ethanol extract of stem and ethanol extract of leaf. The water extract of leaf had the lowest antiproliferative activity (EC 50 >1000 µg dry matter/mL) under the experimental conditions.

Reversing the deleterious effects of aging on neuronal communication and behavior: beneficial properties of fruit polyphenolic compounds2–3

Despite elegant research involving molecular biology studies and determination of the genetic mechanisms of aging, practical information on how to forestall or reverse the deleterious effects of aging may be years away. If this is the case, then it is prudent to try to establish other methods that can be used now to alter the course of aging. Numerous epidemiologic studies have indicated that individuals who consume diets containing large amounts of fruits and vegetables may reduce their risk for developing age-related diseases such as Alzheimer disease. Research from our laboratory suggested that dietary supplementation with fruit or vegetable extracts high in antioxidants (eg, blueberry or spinach extracts) might decrease the enhanced vulnerability to oxidative stress that occurs in aging. These reductions might be expressed as improvements in motor and cognitive behavior. Additional research suggested that mechanisms in addition to antioxidant and antiinflammatory activities might be involved in the beneficial effects of these extracts; the most important of these might be their ability to increase cellular signaling and neuronal communication.

Interaction of the Aryl Hydrocarbon Receptor with Several Constituents from Spinach and Komatsuna Extracts Determined Using in Vitro Bioassay

As a part of our study to clarify the interaction of food ingredients with the aryl hydrocarbon receptor (AhR), we studied the interaction of 10 constituents (phytol, p-coumaric acid, 5 flavonol glycosides, adenosine, guanosine and uridine), isolated from aqueous alcohol extracts of spinach and komatsuna, with the AhR by applying the AhR-based bioassay for dioxins, the Ah-Immunoassay and the AhR-dependent luciferase reporter gene assay. Among them, flavonol glycosides and phytol had slight inhibitory effects on AhR activation by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) at high concentrations, however the effects were not comparable with those produced by kaempferol, regarded as one of the main antagonists of AhR. Also, flavonol glycosides showed weak luciferase inductions at high concentrations.

Effects of feeding experience on feeding responses to spinach in Cassida nebulosa L. (Coleoptera: Chrysomelidae)

A tortoise beetle, Cassida nebulosa feeds on chenopodiaceous weeds, Chenopodium album and C. album var. centrorubrum as its main hosts. The beetle is known as a pest of another chenopodiaceous plant, the sugar beet. However, as a chenopodiaceous vegetable, spinach is rarely harmed by C. nebulosa. Newly emerged adults that had no feeding experience developed a positive feeding response to spinach as well as to C. album var. centrorubrum within 24 h. On the other hand, adults reared on C. album var. centrorubrum did not accept spinach, and their feeding response to spinach was still weak even after rearing on spinach for 4 d. When C. nebulosa were reared on leaves of C. album var. centrorubrum treated with the methanol extracts of spinach, they accepted spinach as well as C. album var. centrorubrum. In contrast, when C. nebulosa were reared on leaves of spinach treated with the methanol extracts of C. album var. centrorubrum, consumption of spinach by the adults was less than that by the adults reared on leaves treated with solvent only. These results indicate that C. nebulosa has the potential to harm spinach due to the habituation to feeding deterrents in spinach. However, the harm to spinach by C. nebulosa could be suppressed because feeding experience on C. album var. centrorubrum can prevent C. nebulosa from habituating to spinach.

Requirement of a relatively high threshold level of Mg(2+) for cell growth of a rhizoplane bacterium, Sphingomonas yanoikuyae EC-S001.

Mg(2+) is one of the essential elements for bacterial cell growth. The presence of the magnesium cation (Mg(2+)) in various concentrations often affects cell growth restoration in plant-associating bacteria. This study attempted to determine whether Mg(2+) levels in Sphingomonas yanoikuyae EC-S001 affected cell growth restoration in the host plant and what the threshold level is. S. yanoikuyae EC-S001, isolated from the rhizoplane of spinach seedlings grown from surface-sterilized seeds under aseptic conditions, displayed uniform dispersion and attachment throughout the rhizoplane and phylloplane of the host seedlings. S. yanoikuyae EC-S001 did not grow in potato-dextrose broth medium but grew well in an aqueous extract of spinach leaves. Chemical investigation of the growth factor in the spinach leaf extract led to identification of the active principle as the magnesium cation. A concentration of ca. 0.10 mM Mg(2+) or more allowed S. yanoikuyae EC-S001 to grow in potato-dextrose broth medium. Some saprophytic and/or diazotrophic bacteria used in our experiment were found to have diverse threshold levels for their Mg(2+) requirements. For example, Burkholderia cepacia EC-K014, originally isolated from the rhizoplane of a Melastoma sp., could grow even in Mg(2+)-free Hoagland's no. 2 medium with saccharose and glutamine (HSG medium) and requires a trace level of Mg(2+) for its growth. In contrast, S. yanoikuyae EC-S001, together with Bacillus subtilis IFO12113, showed the most drastic restoring responses to subsequent addition of 0.98 mM Mg(2+) to Mg(2+)-free HSG medium. Our studies concluded that Mg(2+) is more than just the essential trace element needed for cell growth restoration in S. yanoikuyae EC-S001 and that certain nonculturable bacteria may require a higher concentration of Mg(2+) or another specific essential element for their growth.

Degradation of malathion, in aqueous extracts of asparagus (Asparagus officinalis).

Malathion was incubated in water extracts of vegetables at various temperatures and pH, and the amount of malathion present over time was analyzed by a gas chromatograph with a flame photometric detector. Malathion was degraded to a nondetectable level in a 1% asparagus extract incubated at pH 7.4 and 37 degrees C for 4 h. Carrot extract showed the second highest rate of malathion degradation (76%), followed by kale extract (23.7%), spinach extract (9.7%), and broccoli extract (1.5%) under the same conditions. The highest degradation rates of malathion were observed at 37 degrees C, when three different temperatures were tested (5, 25, and 37 degrees C) at pH 7.4. Rate constants were 0.134 min(-)(1) from a 1% asparagus solution and 0.095 min(-)(1) from a 0.5% asparagus solution. The highest degradation rate of malathion was achieved at pH 9 among the pHs tested (pH 4, 7.4, and 9) in a 0.5% asparagus solution. The 0.5% asparagus solution degraded dicarboxylic acid esters by almost 100% for dimethyl succinate and diethyl adipate, by 64% for diethyl acetyl succinate, and 30% for diethyl benzyl malonate when incubated at pH 9 for 20 min. The results support the hypothesis that the enzyme that degrades malathion in the asparagus solutions is a carboxylesterase.

Unique natural antioxidants (NAOs) and derived purified components inhibit cell cycle progression by downregulation of ppRb and E2F in human PC3 prostate cancer cells

Prostate cancer (PCA) is the leading cause of cancer mortality among older men in Western countries. Epidemiological studies have shown correlation between a lower risk of PCA and a higher consumption of antioxidants. However, the mechanism by which antioxidants exert their effects is still unknown. In the present study, we explored the signaling mechanism through which unique natural antioxidant derived from spinach extract (NAO) exerts their beneficial effects in the chemoprevention of PCA using human PC3 cells. Probing into the effect of NAO and its derived polyphenols on cell-cycle G1 arrest, we found that they cause cell-cycle prolongation. NAO and its two derived purified components exhibited a significant increase in the level of p21 cip1 expression after 36 h of starvation, followed by 18 h of treatment with NAO in the presence of serum. In addition, under similar conditions, the expressed level of Cyclin A and CDK-2 in the PC3 cells was significantly reduced after treatment with NAO or its purified components. Immunoblot analysis demonstrated a significant increase in the hypophosphorylated form of pRb and a decrease in ppRb. NAO and its purified derived components were found to downregulate the protein expression of another member of the pRb family, p107, as well as that of E2F-1. These results suggest that NAO-induced G1 delay and cell cycle prolongation are caused by downregulation of the protein expression of ppRb and E2F in the human PCA cell line PC3.

Treatment of trinitrotoluene by crude plant extracts

Crude plant extract solutions (spinach and parrotfeather) were prepared and spiked with 2,4,6-trinitrotoluene (TNT) (20 mg l −1). 90-h TNT removal by these solutions was compared to controls. Spinach and parrotfeather extract solutions removed 99% and 50% of the initial TNT, respectively; TNT was not eliminated in the controls or in extract solutions where removal activity was deactivated by boiling. A first-order removal constant of 0.052 h −1 was estimated for spinach extract solutions treating 20 mg l −1 TNT concentrations, which compared favorably to intact plant removal. Concentration variation was described by Michaelis–Menton kinetics. Detectable TNT degradation products represented only a fraction of the total TNT transformed, and the transformation favored the formation of 4-aminodinitrotoluene. The results indicated that crude plant extracts transform TNT, without the presence of the live plant.

Development and evaluation of an enriched natural antioxidant preparation obtained from aqueous spinach ( Spinacia oleracea) extracts by an adsorption procedure

Spinach ( Spinacia oleracea) leaves contain antioxidant flavonoids, in particular spinacetin and patuletin. An adsorption procedure for the recovery of these flavonoids from a crude spinach extract was developed and evaluated. Four different resin and charcoal adsorbents, chosen for their high affinity for polyphenolic compounds, were tested in an open batch system. All proved to be very efficient in adsorbing polyphenols. However, while a major portion of the flavonoids could be desorbed from the resin matrices under the experimental conditions imposed by an industrial context, most of these compounds stayed irreversibly bound to the charcoal matrices. The use of a polymeric resin matrix, to purify a spinach crude extract, allowed the removal of almost 80% of the initial extract dry mass, while keeping the flavonoid content nearly constant. Using the nitro blue tetrazolium (NBT) and the DPPH tests to evaluate the antioxidant character of these preparations, it was determined that the spinach flavonoids, as well as the crude aqueous or resin-purified extracts, exhibit high antioxidant activities. Moreover, the antioxidant efficiency of the spinach polyphenol extracts was significantly increased by the elimination of a major part of non-phenolic components.

Natural essential oils as reducing agents of peroxidase activity in leafy vegetables

The effectiveness of natural essential oils eucalyptus ( Eucalyptus globulus), tea tree ( Melaleuca alternifolia), melisa ( Melissa officinalis), roomer ( Rosmarinus officinalis), clove ( Syzygium aromaticum) and lemon ( Citrus limonum) to reduce peroxidase activity of organic leafy vegetables extracts was evaluated. Three oil concentrations at the minimum inhibitory concentration (MIC, 2×MIC and 4×MIC) of each natural essential oils were used. Crude vegetable extracts of Swiss chard, spinach, lettuce, butter lettuce and cabbage were the source of peroxidase activity. The effectiveness of the essential oils as natural antioxidants varied with the enzyme sources. At the MIC, clove, rosemary, lemon, melisa and tea tree had the high antioxidant properties being clove more effective than the other oils.

Enriquecimento de macarrão tipo tubo (massa curta) com derivados de levedura (Saccharomyces sp.): impacto nutricional e sensorial

Esta pesquisa teve como objetivo investigar a viabilidade técnica e os melhores níveis de adição dos derivados de levedura, autolisado (AT) e extrato (Ex) ao macarrão, visando uma melhoria do valor nutritivo sem diminuir a sua aceitação pelo consumidor. Adição de 5 ou de 7,5% de derivado de levedura melhorou o escore de aminoácidos essenciais (EAE) de 9 e 19%, respectivamente, para o AT e o Ex. O índice que mede a capacidade da proteína de promover crescimento (NPR) se elevou de 25 e 40% para a adição de 7,5% de autolisado ou de extrato, respectivamente. No macarrão massa branca, a adição de 5% de Ex não alterou a aceitação do produto, contudo 5% de AT teve um impacto negativo na aceitação pelo consumidor. A adição à massa de extrato de espinafre (massa verde) de 7,5% de derivado de levedura afetou apenas a aparência do macarrão adicionado de extrato e a aparência e a cor do macarrão com 7,5% de autolisado, em relação ao macarrão contendo apenas extrato de espinafre. A adição de espinafre à massa melhorou as características sensoriais do macarrão adicionado de 7,5% de autolisado. As características tecnológicas de fabricação dos macarrões não foram alteradas pela adição à massa dos derivados de levedura.

Composition, Efficacy, and Safety of Spinach Extracts

Spinach leaves, containing several active components, including flavonoids, exhibit antioxidative, antiproliferative, and antiinflammatory properties in biological systems. Spinach extracts have been demonstrated to exert numerous beneficial effects, such as chemo- and central nervous system protection and anticancer and antiaging functions. In this review article, we present a compilation of data generated in our laboratories and those of other investigators describing the chemical composition of spinach, its beneficial effects, relative safety information, and its recommended inclusion in the human diet. A powerful, water-soluble, natural antioxidant mixture (NAO), which specifically inhibits the lipoxygenase enzyme, was isolated from spinach leaves. The antioxidative activity of NAO has been compared to that of other known antioxidants and found to be superior in vitro and in vivo to that of green tea,N-acetylcysteine (NAC), butylated hydroxytoluene (BHT), and vitamin E. NAO has been tested for safety and is well tolerated in several species, such as mouse, rat, and rabbit. NAO has been found to be nonmutagenic and has shown promising anticarcinogenic effects in a few experimental models, such as skin and prostate cancer; it has not shown any target-organ toxicity or side effects. The current review provides epidemiological and preclinical data supporting the efficacy of extracts of spinach and the safety of its consumption.