404 research outputs found
Investigating the potential applications of lentil seed components in mechanically separated chicken meat systems
The overall goal of this project was to explore the potential applications of lentil seed components in meat systems. Therefore, their functionality as an antioxidant and a binder were investigated in four studies. In study one, the antioxidant efficacy of water and (70% v/v) ethanol extracts of seed coat from two lentil cultivars (CDC Greenland, a large green and CDC Maxim, a small red variety) were studied in in vitro assays and a mechanically separated chicken (MSC) model meat system. The total phenolics (TPC) extracted in aqueous (70%) ethanol (43.96–50.46 mg gallic acid equivalents (GAE)/g) were higher (p<0.05) than that of water extracts (41.63 –44.30 mg GAE/g). Extracts demonstrated concentration-dependent antioxidant activity irrespective of cultivar or extraction solvent. The addition of seed coat extracts (500 ppm TPC) resulted in significant (p<0.001) inhibition of lipid oxidation in MSC during cooking and storage and there was an 11-fold difference in TBARS values between treated and control samples after seven days of refrigerated storage. The antioxidant capacity of seed coat was comparable to Herbalox, sodium ascorbate, (+)-catechin, and (+/-) - α- tocopherol.
In study two, the phenolic composition and antioxidant capacity of water extracts of seven lentil cultivars (CDC Greenland, CDC Greenstar, CDC Maxim, CDC Robin, CDC SB-3, ZT-4 and 6205-ZT) were determined. TPC, flavonoids (TFC) and condensed tannins (CTC) in normal tannin seed coats ranged from 35.88 to 39.72 mg GAE/g, 3.50 to 5.14 mg catechin equivalents (CE)/g and 21.63 to 28.07 mg CE/g, respectively. Condensed tannin was absent in zero tannin cultivars and TPC was around 6-times lower than that of normal tannin cultivars. Kaempferol tetraglycoside, catechin-3-glucoside, and procyanidins were the most abundant phenolic compounds in normal tannin cultivars, whereas kaempferol tetraglycoside was dominant in zero tannin cultivars. Antioxidant activity measured by DPPH, ABTS, and ferrous ion chelation assays showed strong activity (>70%) at concentrations higher than 400 ppm of TPC. Overall, lentil cultivars with seed coat had relatively higher phenolic content and antioxidant activity compared to other cultivars. TPC, TFC and CTC concentrations were highly correlated (r = 0.93 to 0.98) with antioxidant activities showing their positive contribution to antioxidant capacity of seed coat. Both free radical scavenging activity and chelation mechanisms were involved in the overall antioxidant efficacy of seed components.
The objective of the third study was to evaluate the applicability of lentil seed components (flour, seed coat and seed coat water extracts) as replacements for synthetic phosphates in non-cured bologna sausage. The combination of infra-red heated (IR) lentil flour and seed coat extracts (300 ppm or 500 ppm of TPC) were able to replace the techno-functional properties of synthetic phosphates with no negative effects on water-holding, texture, and sensory properties and oxidative stability of bologna, while seed coat itself had negative impact on color, flavor and texture attributes.
The fourth study investigated the efficacy of infra-red heated lentil flour as a binder in wiener type chicken sausages developed for the Sri Lankan market. The water-holding and texture properties, and the proximate composition of the sausages containing lentil flour, were similar to those of the commercial formulation made with isolated soy protein and corn starch, and the level of lentil flour added (4% to 8%) had minimal effect. Oxidative stability of sausages formulated with lentil flour was similar to the commercial formulation, and samples with lentil flour showed no difference in oxidative stability compared to those added sodium nitrite. The cross-cultural consumer acceptability tests conducted with three consumer panels (Canadian consumers, Sri Lankan consumers living in Canada and Sri Lankan consumers living in Sri Lanka, each consisting of 60 panelists) revealed that the liking for sensory properties and overall acceptability of MSC sausages were similar between the commercial product and those with lentil flour added, demonstrating that lentil flour could be an economical and effective meat replacer product. The functionality of lentil flour as a binder were possibly attributable to its high amounts of starch and protein.
In conclusion, this study demonstrated the potential for use of lentil seed components as a potential plant antioxidant and binder in meat products without decline in sensory characteristics and nutritive value. The findings of this study will help in the development of clean label meat products, nutraceutical applications, and breeding strategies for lentil cultivars with health and functional benefits
The role of eco-villages in community-based environmental education: a comparative study of communities in Sri Lanka and the United Kingdom
This thesis explores the role of eco-villages in community-based environmental education and presents a comparative study of eco-communities in Sri Lanka and the UK. In Sri Lanka, the focus is upon the village of Damniyamgama, and in the UK the focus is upon Findhorn village in Scotland. Community-based environmental education is in its infancy, yet is gradually becoming recognised as a crucial process given the rapidly deteriorating 'environmental health' of planet Earth. This thesis sets the context by outlining some of the major environmental problems the world faces. It then addresses the development of environmental education, theoretical perspectives relevant to the emerging field of community-based environmental education, the role of NGOs and the concept of an eco-village. The empirical dimension is presented as research-based case studies of the two contrasting eco-villages. Visits were made to both sites and in-depth interviews were conducted. Data from these interviews were combined with information derived from informal discussions, observations and secondary sources to enable analysis to be undertaken. Through this combination of literature review and empirical research, the thesis examines how successfully concepts and practices of sustainable development are incorporated within Damniyamgama and Findhorn eco-villages; how educational activities are conducted in both locations and the role that the villages play in changing attitudes and practices. Comparisons are made between the case study villages and transferable outcomes are identified. Finally the thesis identifies areas that would benefit from further development in the eco-villages studied. It is concluded that a successful eco-village is a socially harmonious, economically viable and ecologically sustainable settlement that enables human beings to live co operatively with each other and with the natural environment. Eco-villages can be splendid settings for community-based environmental education, which changes personal attitudes and behaviours relating to the environment. This thesis makes an original contribution to the literature of environmental education. Little has been published on the emerging process of community-based environmental education; even less on the educational role of eco-villages. It is believed that no previous empirical study has focused on a comparison of community-based environmental education or indeed a comparison of eco-communities in Sri Lanka and the United Kingdom
Impact of Early-Life Exposure to Bisphenol A on Survival and Histopathology of Liver and Kidney of Zebrafish (Danio rerio)
Bisphenol A (BPA) is a highly used chemical and an ubiquitous environmental contaminant in urban aquatic ecosystems. BPA disrupts hormonal and metabolic pathways of living organisms through its endocrine disrupting activity. Early-life BPA exposure could perturb key developmental processes, thus affecting the survival of living organisms. BPA is known to accumulate in water bodies, therefore it is important to understand the impact of BPA on aquatic organisms and ecosystem health. The objective of this study was to investigate the impact of early-life BPA exposure on survival and histology of kidney and liver of zebrafish. Zebrafish model is widely used in environmental monitoring and BPA-related studies. During the study zebrafish were treated for 60 days with two environmentally prevalent concentrations of BPA (1 μg/L and10 μg/L) and with a treatment control. Twenty wild-type juvenile zebrafish of age 35 dpf (days post fertilisation) were assigned to triplicate tanks and were treated until maturity in 95 dpf. Water of the tanks were changed once per three days. Survival percentage of the fish were calculated weekly. The kidney and liver of a sample of five fish from control treatment and 10 μg/L of BPA were obtained at 95 dpf for histopathological study. Kidney and liver sections were stained using heamatoxylin/eosin and examined under light microscope for structural pathology. The highest mean survival of 90% was observed in the control group at the end of the treatment period while, 56.57% and 41.67 % of survival were observed at 1 μg/L and 10 μg/L of BPA treatments respectively. This observation led to the conclusion that BPA has a significant impact on fish survival where high BPA concentrations resulted in significantly low survival. Histopathological analysis of the kidneys of fish treated with 10 μg/L of BPA revealed damaged renal tubules, shrinkage of tubules or tubule lumen, degeneration of tubules and hematopoietic tissue when compared with the control group. The liver histopathology of BPA-treated fish revealed lipid accumulation in hepatocytes. The reduced survival and structural distortion of liver and kidney of zebrafish in BPA-treated tanks could be due to chronic early-life BPA exposure as the quality of water significantlyaffects the fish survival, growth and development. It can be concluded that early-life exposure to environmentally prevalent doses of BPA can result in increased mortality in zebrafish model. This study calls for more comprehensive studies to understand the physiological impact of early-life BPA exposure on aquatic organisms.Keywords: Bisphenol A, Zebrafish, Survival, Histology, Liver, Kidne
Surface Functionalized Mesoporous Silica Nanoparticles for Enhanced Removal of Heavy Metals: A Review
Human health and environmental sustainability are strongly influenced by the contamination of water resources with hazardous heavy metal ions due to the accumulation in human body via food chains. Thereby, researchers’ attention has been paid on effective methods for heavy metal ion scavenging to prevent them releasing to environment. Notably, Mesoporous Silica Nanoparticles (MSNPs) with high surface area, massive surface area to volume ratio, large pore volume and uniform pore distribution play a crucial role in addressing this challenge. Additionally, researchers focus on novel surface functionalization methods of MSNPs with suitable organic and inorganic moieties to amplify the adsorption efficiency of heavy metals. MSNPs possess easily functionalizable surface which facilitates the modifications and enhanced removal of heavy metals. The review article summarizes the different moieties used for functionalization of MSNPs such as amino, thio, carboxyl, phenyl, cyano groups, different types of polymers, inorganic functional groups. Further, a comparison has been made between functional and unmodified MSNPs to elaborate how these modifications have enhanced the removal performance of heavy metals in water. Further, this review provides an overview on different synthesis routes and structure directing agent used in synthesis of MSNPs. Moreover, pH effect on adsorption andreusability of modified NPs, while illustrating the mechanism of adsorption on to modified MSNPs surface has also been elaborated. Maximum adsorption capacity of each functional moiety has been taken into consideration with the aim of supporting future advancements.
Keywords: Adsorption, Mesoporous silica nanoparticles, Heavy metals, Functionalization, Maximum adsorption capacit
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