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Leafy Vegetables (leafy + vegetable)
Kinds of Leafy Vegetables Selected AbstractsShelf Life of Leafy Vegetables Treated with Natural Essential OilsJOURNAL OF FOOD SCIENCE, Issue 2 2004A.G. Ponce ABSTRACT: Essential oils as natural sanitizing agents were sprayed on Swiss chard leaves produced by organic methods. Samples were stored at 0 and 5°C and 97% to 98% relative humidity. Microbial populations, peroxidase activity, and sensory attributes were monitored during storage. No significant differences were observed between treated and control samples stored at 0°C. However, samples treated with the essential oils of eucalyptus, tea tree, and clove and stored at 5°C presented microbial counts significantly lower than those of control samples. The essential oils of eucalyptus, tea tree, lemon, rosemary, and clove presented peroxidase activity inhibition that, in the case of eucalyptus, increased to 65% during storage. Although some of the essential oils did appear to reduce microbial counts and peroxidase activity compared with controls, they were not effective in extending the shelflife of the Swiss chard leaves from a sensory point of view. [source] Calcium Absorption from Commonly Consumed Vegetables in Healthy Thai WomenJOURNAL OF FOOD SCIENCE, Issue 9 2008S. Charoenkiatkul ABSTRACT:, The absorbability of calcium from ivy gourd, a green leafy vegetable (Coccinia grandix Voigt.) and winged bean young pods (Psophocarpus tetragonolobus [L] DC) were measured in 19 healthy adult women aged 20 to 45 y, in a 3-way, randomized-order, crossover design with an average calcium load of 100 mg and milk as the referent. The test meals were extrinsically labeled with 44Ca and given with rice as breakfast after an overnight fast. Absorption of calcium was determined on a blood sample drawn 5 h after ingestion of the test meal. Fractional calcium absorption (X± SD) was 0.391 ± 0.128 from winged beans, 0.476 ± 0.109 from ivy gourd, and 0.552 ± 0.119 from milk. The difference in fractional calcium absorption for these 2 vegetables was significant (P < 0.05) and the fractional calcium absorption from these 2 vegetables were both significantly lower than from milk. The difference was partly accounted for by the phytate, oxalate, and dietary fiber content of the vegetables. However, calcium bioavailability of these 2 vegetables, commonly consumed among Thais, was relatively good compared to milk (71% to 86% of milk) and could be generally recommended to the public as calcium sources other than milk and Brassica vegetables. [source] Genomic DNA fingerprints as a tool for identifying cultivated types of radicchio (Cichorium intybus L.) from Veneto, ItalyPLANT BREEDING, Issue 2 2003G. Barcaccia Abstract Red or variegated chicory (Cichorium intybus L., 2n = 2 ×= 18) native to, and very extensively cultivated in north-eastern Italy as a leafy vegetable, locally called ,radicchio', includes different types which represent valuable high-quality crops. The five major types of radicchio cultivated in the Veneto region were investigated by polymerase chain reaction (PCR)-derived markers. The experimental material was represented by two outbred populations (one of ,Variegato di Castel-franco' (CF) and one of ,Rosso di Verona' (VR)) and by eight inbred lines (three of early ,Rosso di Treviso' (TVP), three of late ,Rosso di Treviso' (TVT) and two of ,Rosso di Chioggia' (CH)). A total of 96 individual plant DNAs and 16 bulked DNAs of six plants each were assayed. The different types were well distinguished from one another if analysed by means of bulks using amplified fragment length polymorphism markers at the population level, while they were not if analysed at the individual level using random amplified polymorphic DNA, inter-simple sequence repeat and Arbitrarily Primed (AP)-PCR markers. The genetic variation was shown to be much higher within types than between types. This result suggests that, in each radicchio type, populations produced by breeders through controlled intercrossing (VR and CF) or repeated selfing (TVP, TVT and CH) conserved their well-separated gene pools over the years. The setting up of a molecular reference system seems to be feasible and suitable both for the precise identification of the single types of radicchio and for the evaluation of the extent of natural hybridization that can occur between different types. [source] Localization of deposited polycyclic aromatic hydrocarbons in leaves of PlantagoENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 5 2001Martine I. Bakker Abstract After deposition to foliage, polycyclic aromatic hydrocarbons (PAHs) may remain on the leaf surface, accumulate in the cuticular wax, or diffuse into the remaining interior of the plant. In a field study, the location of deposited PAHs in the leaves of two Plantago species was determined. To this aim, leaves of Plantago major and Plantago media were divided into three fractions. First, the leaves were washed (wash-off fraction), then cuticular wax was extracted (wax fraction). Finally, the remaining leaf material was extracted (interior fraction). The presence of PAHs could be demonstrated in all three fractions. For both plants, the distribution of PAHs over the three fractions changed with molecular weight (mol wt) of the PAHs. The wash-off fraction increased with increasing molecular weight, likely because high molecular-weight PAHs occur predominantly bound to particles, which can be readily washed off from the leaves. In contrast, the amount of PAHs detected in the interior of the leaves decreased with increasing molecular weight. This can be explained by a slow desorption of the PAHs from the particles and a low diffusion rate of the larger molecules. This study shows that washing reduces the amount of high molecular-weight PAHs on plant surfaces. Therefore, washing of leafy vegetables is important to minimize human dietary intake of PAHs. [source] Greater vegetable and fruit intake is associated with a lower risk of breast cancer among Chinese womenINTERNATIONAL JOURNAL OF CANCER, Issue 1 2009Cai-Xia Zhang Abstract The effect of vegetable and fruit consumption on breast cancer risk is controversial. We examined the association between vegetable and fruit intake and breast cancer risk in a hospital-based case,control study conducted in Guangdong, China. Four hundred and thirty-eight cases were frequency matched to 438 controls by age (5-year interval) and residence (rural/urban). Dietary intake was assessed by face-to-face interviews using a validated food frequency questionnaire. Multivariate logistic regression was used to estimate the odds ratios (ORs) and 95% confidence interval (CI) after adjusting for various potential confounders. Total vegetable and fruit intake was found to be inversely associated with breast cancer risk. The ORs of the highest quartile relative to the lowest quartile of total vegetable and fruit intake were 0.28 (95% CI 0.18,0.43) and 0.53 (95% CI 0.34,0.82), respectively. Consumption of individual vegetable and fruit groups such as dark green leafy vegetables, cruciferous vegetables, carrots and tomatoes, banana, watermelon/papaya/cantaloupe were all inversely and significantly related with breast cancer risk. An inverse association was also observed for vitamin A, carotene, vitamin C, vitamin E, and fiber intake. These data indicate that greater intake of vegetables and fruits is associated with a decreased risk of breast cancer among Chinese women residing in Guangdong. © 2009 UICC [source] The extent of marketability and consumer preferences for traditional leafy vegetables , a case study at selected markets in GhanaINTERNATIONAL JOURNAL OF CONSUMER STUDIES, Issue 3 2009Wilhemina Quaye Abstract This paper reports on a survey conducted at two major marketing centres in Ghana; Tamale in the dry savannah zone and Kumasi in the forest zone. One hundred traders were interviewed using a semi-structured questionnaire and focus groups discussions held on traders' perceptions and consumer preferences, relative importance and indigenous nutritional knowledge of traditional leafy vegetables (TLVs). The survey established that, with the exception of Xanthosoma mafafa (cocoyam leaves), inter-market distribution of TLVs is limited because of their perishable nature, narrow utilization base and lack of storage techniques. Socio-culturally related factors limiting the distribution of TLVs include regional diversity and ethnic differences in the dietary patterns of the Ghanaian populace, inadequate knowledge about the methods of preparations as well as nutritional and medicinal values of TLVs. The most preferred TLVs as reflected in the consumers' buying behaviour and traders' perceptions are Xanthosoma mafafa (cocoyam leaves), Corchorus spp.(Ayoyo), Amaranthus spp (Alefu) and Hibicus sabdariffa (Bra). The order of preference in the forest zone is Xanthosoma mafafa (cocoyam leaves) > Corchorus spp.(Ayoyo) > Amaranthus spp (Alefu) > Hibicus sabdariffa (Bra), while the reverse order pertains in the savannah zone. [source] Glutamine Nitrogen and Ammonium Nitrogen Supplied as a Nitrogen Source Is Not Converted into Nitrate Nitrogen of Plant Tissues of Hydroponically Grown Pak-Choi (Brassica chinensis L.)JOURNAL OF FOOD SCIENCE, Issue 2 2009H.-J. Wang ABSTRACT:, Many vegetables, especially leafy vegetables, accumulate NO,3 -N in their edible portions. High nitrate levels in vegetables constitute a health hazard, such as cancers and blue baby syndrome. The aim of this study was to determine if (1) ammonium nitrogen (NH+4 -N) and glutamine-nitrogen (Gln-N) absorbed by plant roots is converted into nitrate-nitrogen of pak-choi (Brassica chinensis L.) tissues, and (2) if nitrate-nitrogen (NO,3 -N) accumulation and concentration of pak-choi tissues linearly increase with increasing NO,3 -N supply when grown in nutrient solution. In experiment 1, 4 different nitrogen treatments (no nitrogen, NH+4 -N, Gln-N, and NO,3 -N) with equal total N concentrations in treatments with added N were applied under sterile nutrient medium culture conditions. In experiment 2, 5 concentrations of N (from 0 to 48 mM), supplied as NO,3 -N in the nutrient solution, were tested. The results showed that Gln-N and NH+4 -N added to the nutrient media were not converted into nitrate-nitrogen of plant tissues. Also, NO,3 -N accumulation in the pak-choi tissues was the highest when plants were supplied 24 mM NO,3 -N in the media. The NO,3 -N concentration in plant tissues was quadratically correlated to the NO,3 -N concentration supplied in the nutrient solution. [source] Effects of lutein and zeaxanthin on aspects of eye healthJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 1 2010Le Ma Abstract Lutein and zeaxanthin are members of the oxygenated carotenoids found particularly in egg yolks and dark-green leafy vegetables. A great deal of research has focused on their beneficial roles in eye health. The present article summarises the current literature related to the bioactivity of these carotenoids, emphasising their effects and possible mechanisms of action in relation to human eye health. Available evidence demonstrates that lutein and zeaxanthin are widely distributed in a number of body tissues and are uniquely concentrated in the retina and lens, indicating that each has a possible specific function in these two vital ocular tissues. Most of epidemiological studies and clinical trials support the notion that lutein and zeaxanthin have a potential role in the prevention and treatment of certain eye diseases such as age-related macular degeneration, cataract and retinitis pigmentosa. The biological mechanisms for the protective effects of these carotenoids may include powerful blue-light filtering activities and antioxidant properties. Although most studies point towards significant health benefits from lutein and zeaxanthin, further large-scale randomised supplementation trials are needed to define their effects on ocular function in health and disease. Copyright © 2009 Society of Chemical Industry [source] Antioxidant properties of polar and non-polar extracts of some tropical green leafy vegetablesJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 14 2008Ganiyu Oboh Abstract BACKGROUND: The higher consumption of vegetables and fruits could be a practical approach to the management of oxidative stress. The present study sought to compare the antioxidant properties of polar and non-polar constituents of some tropical green leafy vegetables (Struchium sparganophora, Amaranthus cruentus, Telfairia occidentalis, Ocimum gratissimum, Talinium triangulare, Cnidoscolous aconitifolius and Vernonia amygdalina). RESULTS: The polar antioxidant constituents (total phenol (3330,17 572 mg kg,1), total flavonoid (1668,4306 mg kg,1) and vitamin C (224,642 mg kg,1)) were higher than the non-polar antioxidant constituents (total phenol (703,3115 mg kg,1), total flavonoid (130,1303 mg kg,1) and carotenoids (132,1303 mg kg,1)). Furthermore, the polar extracts had a significantly higher (P < 0.05) 1,1-diphenyl-2-picrylhydrazyl radical scavenging ability (except T. triangulare), total antioxidant capacity, reducing power (except T. triangulare and A. cruentus) and Fe(II) chelating ability (except C. aconitifolius and S. sparganophora). However, the polar and non-polar extract of O. gratissimum had the highest antioxidant properties while that of T. triangulare had the least antioxidant properties. CONCLUSION: The polar extract of most of the vegetables had higher antioxidant properties than the non-polar extract, with O. gratissimum extracts having the highest antioxidant properties. Copyright © 2008 Society of Chemical Industry [source] The production of provitamin A-rich vegetables in home-gardens as a means of addressing vitamin A deficiency in rural African communitiesJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 3 2007Mieke Faber Abstract Vitamin A deficiency remains a public health problem in the developing world. The highest prevalence of vitamin A deficiency is in Africa and Asia (>30%). Dietary modification, a long-term strategy to address vitamin A deficiency, complements food fortification and vitamin A supplementation programmes. Provitamin A carotenoids from foods of plant origin are more affordable than preformed vitamin A from animal foods, and many resource-poor households rely on yellow/orange-fleshed vegetables and fruits and dark-green leafy vegetables as their main source of vitamin A. The provitamin A carotenoid content in plant foods varies widely and differences among cultivars of the same food exist. Several factors influence the bioavailability of provitamin A carotenoids. The potential contribution of plant foods to vitamin A status depends on the retention of provitamin A carotenoids after storage, preparation and processing. Home-gardens can provide households with direct access to provitamin A-rich vegetables that are not readily available or within their financial reach. The components and critical issues of home-garden projects are described. Copyright © 2006 Society of Chemical Industry [source] In vitro bioavailability of calcium and iron from selected green leafy vegetables,JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 13 2006Sheetal Gupta Abstract The objective of the present investigation was to analyze the relative influence of oxalic acid, phytic acid, tannin and dietary fiber on in vitro availability of iron and calcium from green leafy vegetables (GLV). Thirteen GLV were selected and analyzed for iron, calcium, oxalic acid, phytic acid, tannin and dietary fiber contents using standard methods. The bioavailability of calcium and iron in the GLV was estimated by equilibrium dialysis. Oxalic acid content was less than 1 g kg,1 in four greens and ranged between 1.22 to 11.98 g kg,1 in the remaining. Dietary fiber ranged from 19.5 to 113.7 g kg,1. Tannin content ranged between 0.6138 and 2.1159 g kg,1 with the exception of two GLV that had 0.1332 and 14.8619 g kg,1. Four GLV were found to have approximately 40% bioavailable iron, while the others were in the range of 6,30%. In vitro available calcium was less than or equal to 25% in eight GLV and between 34% and 52% in five GLV. Multiple regression analysis revealed that these factors together accounted for 53% (r2 = 0.53) and 45% (r2 = 0.45) inhibition of iron and calcium absorption, respectively. These findings infer that calcium and iron availability is influenced by the constituents present in the GLV. Copyright © 2006 Society of Chemical Industry [source] | |||||||||||||