42 research outputs found
Purposeful field trip:Impact on experiential learning opportunities and critical thinking skills
No full textWhile Bloom's taxonomy is a well-established learning hierarchy*higher-order thinking skills (HOTS)*defined as the three upper levels*are seldom attained due to traditional teaching practices and time constraints of units or subjects. Therefore*adopting innovative pedagogy models like experiential learning provides opportunities for the demonstration and development of HOTS. The study's objective shows that field trips are crucial components of experiential learning*and when designed with a purpose*promote higher-order thinking skills. This study used a descriptive design*specifically videos*to collect qualitative data for small sample sizes followed by a structured questionnaire consisting of closed questions. All videos were transcribed*and thematic analyses were used. The quantitative data were analysed descriptively*and data were presented using frequency distribution. It was found that this field trip assessment design enabled the skills demonstration spanning Bloom's learning spectrum. Furthermore*HOTS were used more frequently than basic thinking skills. A quantitative survey on student perceptions revealed that pre-trip activities are equally important as during-trip activities. Findings from this exploratory study provide insights for future education-related research in the field of HOTS*transferable skills*and values.</p
HPLC fucoxanthin profiles of a microalga, a macroalga and a pure fucoxanthin standard
No full textData in this article illustrate representative fucoxanthin chromatograms of a microalga, Chaetoceros calcitrans; a macroalga, Saccharina japonica and; a pure fucoxanthin standard. High performance liquid chromatography (HPLC) eluted fucoxanthin at the 7.008±0.024th min. This data article refers to the research article ‘‘Antioxidant capacities of fucoxanthin-producing algae as influenced by their carotenoid and phenolic contents’’ Foo et al. [1]; where a more comprehensive data interpretation and analysis is explained
Manipulation of Microalgal Lipid Production: A Genetic Engineering Aspect
No full textInterests in microalgal lipids as green and renewable energy sources are piquing as cheap hydrocarbon fossil fuels reach their limit. Lipids from microalgae have important human uses, i.e., energy, food, and pharmaceuticals, depending on its quantity and quality. Genetic engineering is the introduction or suppression of a target gene for the selective expression of a bio-product, e.g., hydrocarbons for fuel or polyunsaturated fatty acids (PUFAs) for food, at a favorable quantity. Past studies like nitrogen starvation or salinity stress have shown to increase lipid contents of microalgae; however, studies on the molecular mechanisms underlying these stress-induced lipid productions remain limited. Next, complementing environmental stress manipulation with genetic engineering would potentially be a better and more effective approach to increase microalgae lipid production and accumulation. There are generally two approaches to enhance microalgae lipid production on a molecular level: firstly, overexpression and improvement of key enzymes involved in fatty acid and isoprenoid biosynthesis and, secondly, repression of lipid catabolic and competitive pathways such as beta-oxidation and starch synthesis. This review provides an update of microalgae lipid research findings to date and aims to address recent system biology discoveries and approaches on microalgae lipid production, the roadblocks encountered, and help needed to realize the ultimate goal, that is, microalgal lipids as sustainable resources for energy and high-value products
Storage and degradation kinetics of physicochemical and bioactive attributes in microalgal-derived fucoxanthin-rich microcapsules
No full textMicroencapsulation can improve carotenoid stability by slowing down degradation. Studies on the production and processing effects of microencapsulated carotenoids were reported in the past however long-term storage studies on fucoxanthin stability remains limited. This study investigated the effects of an eighteen-week storage period across four conditions on fucoxanthin derived from the diatom, Chaetoceros calcitrans. The fucoxanthin powders were prepared using two microencapsulation methods i.e., freeze drying and spray drying. Briefly, the microcapsules produced were stored in amber bottles under room temperature (25 °C) or refrigerated (4 °C) in the dark or in the presence of light. Samples were collected every two weeks where the physicochemical characteristics, carotenoid stability and antioxidant activity were evaluated. It was found that the freeze-dried microcapsule stored in 4 °C showed significantly (p 25 °C (dark) > 40 °C (dark) > 25 °C (light). This finding offer useful insights into optimizing fucoxanthin microencapsulation methods, maintaining product quality during storage and distribution, and ensuring compliance with quality standards of fucoxanthin-based products available to consumers across the production and distribution chain
Online electronic information resources on business management
No full textThe paper discusses the Post Graduate Management Institutes in South Gujarat and the problems of their libraries. The author has described the freely available Internet resources on Business management like E-journals, business databases, stock exchanges, management virtual libraries etc. and has also started to compile the links of these free internet resources at URL http://www.geocities.com/ghoshtbin to integrate the resources in a uniform location for the benefit of the Management faculties and students
Freely available online information sources and their impact on libraries and information centres
No full textSince past few years free online information sources like e-journals, e-books, e-data- bases have increased cnsiderably. The traditional library systems are going to transform into digital library systems and different projects like Gutenberg e-book project, Virginia Tech. Digital Library Project, University of California Digital Library project etc. have been undertaken. The author has started to compile the links of such freely available online information sources on the Internet at URL: http://www.geocities.com/ ghosh_tbd and described the same in this paper. The paper also describes the impact on collection development, budget and technical processing etc. of the Library and Information centre
Physicochemical, microstructure and antioxidant properties of microalgae-derived fucoxanthin rich microcapsules
No full textThe conjugated double bonds in carotenoids confer antioxidant activities but also makes it unstable. The purpose of this study was to preserve the antioxidant activity of fucoxanthin rich fraction extracted from the microalgae, Chaetoceros calcitrans, via microencapsulation. The effect of selected microencapsulation parameters i.e., drying process, total solid content, type of carrier agent and emulsifier to the physicochemical, microstructure and antioxidant properties of the resulting microcapsule, were investigated. When compared to spray-dried microcapsules, the freeze-dried microcapsules showed better carotenoid preservation and antioxidant activities. Nevertheless, both spray-dried and freeze-dried microcapsules reported water solubility index, moisture, and water activity well within food powder recommended values. Among the formulations, formulation with 40% carrier agent at 1:1 maltodextrin: gum Arabic and 1% w/w Tween 20 emulsifier successfully microencapsulated fucoxanthin with the highest carotenoid and antioxidant activities (p < 0.05), both in freeze-dried and spray-dried microcapsules. This study found that the produced fucoxanthin microcapsule showed good bioactivity retainment leading to wider application possibilities where the microencapsulation formulation could prove useful for other carotenoids too
Qualitative and quantitative changes in the components of irradiated foodstuffs. Suggestions for further analytical studies as a contribution to the evaluation of wholesomeness
No full textEvaluation of high-pressure homogenization as a pretreatment for the extraction and drying of 6-gingerol from ginger
No full text<jats:p>6-Gingerol is the major biologically active component found in the ginger rhizome, and this study investigated the effect of high-pressure homogenization pretreatment on the recovery of 6-gingerol.</jats:p>
Microbubble-microalgae attachment in ionic liquids (ILs) for efficient microalgae harvesting via foam flotation
No full textFoam flotation has proven to be a promising method for harvesting microalgae on a commercial scale. However, high cost and low harvesting efficiency significantly impact the feasibility of this approach. Much of the harvesting performance hinges on the mechanics of bubble-microalgae attachment and the surfactants that facilitate this. This study investigates the microbubble-microalgae interaction (attachment) in ionic liquid of various carbon chain lengths. The dominance of hydrophobic attachment was evident when microalgae was most hydrophobic in ionic liquid 1,3-didecyl-2-methylimidazolium chloride ([C10C10MIM][CI]) of 90 ppm concentration. This coincided with the highest microbubble contact angle measurement of 40°, while a lower angle of 31° was observed during electrostatic attachment dominant conditions, at [[C10C10MIM][CI] concentration of 25 ppm. Gibb's Free energy was used to correlate the probability of attachment to contact angle measurements, indicating that the spontaneity of attachment occurring was higher at 90 ppm, with −7.61 mN/m, while at 25 ppm, the Gibb's free energy was only −4.98 mN/m. Furthermore, bench-scaled laboratory flotation results showed that at 90 ppm, the imidazolium-based ionic liquid [C10C10MIM][CI] achieved a maximum harvesting efficiency of 99 %, outperforming commercial surfactant cetyltrimethylammonium bromide (CTAB) by 15.2 %, further concurring the dominance of hydrophobic attachment of microbubble-microalgae. These results display the viability of ionic liquids as promising alternatives to commercial chemical surfactants.</p
