Optimization of Ultrasonic-Assisted Enzymatic Extraction of Freeze-Dried Sea Buckthorn (<i>Hippophae rhamnoides</i> L.) Berry Oil Using Response Surface Methodology

The ultrasound-assisted extraction (UAE) of oil has received immense importance nowadays because of the enormous benefits the process offers. However, the literature evaluating this process is scarce for sea buckthorn oil. Furthermore, to date, to the best of our knowledge, a study evaluating the combined use of enzymes and UAE for this oil is lacking. In this study, oil from freeze-dried sea buckthorn berries was extracted using ultrasound-assisted enzymatic extraction (UAEE) and the effect of variables (time, enzyme concentration, and solvent to sample ratio) was evaluated on oil yield and its physiochemical properties (acid value, peroxide value, iodine value, density, and color). The optimum conditions were determined using the response surface methodology. The optimum conditions established were 5.08 mL/g, 14.65 min, and 3.13 U/g for a solvent to sample ratio, ultra-sonication time, and enzyme units, respectively. The oil yield was 18.32%. Physicochemical parameters were found better in UAEE oil than in the Soxhlet-extracted oil. Gas chromatography detected relatively higher levels of fatty acids, including palmitic, palmitoleic, and oleic acids in UAEE oil. The optimum conditions were also verified for adequacy by validation and results were matched with predicted values with 0.8 to 1.5 error %, which states that the model can be utilized to predict oil yield percentage

Technical Support: Towards Mitigating Effects of Computer Anxiety on Acceptance of E-Assessment Amongst University Students in Sub Saharan African Countries

Part 1: Technology Adoption, Diffusion and Ubiquitous ComputingInternational audienceThe application of Information technology in educational context and environment has dramatically changed the pattern at which people teach and learn. Institutions of higher learning globally are increasingly adopting e-Assessment as a replacement for traditional pen on paper examination due to its cost effectiveness, improved reliability due to machine marking, accurate and timely assessment. In spite of the numerous benefits of e-assessment, it is unclear if University students in Sub Saharan African Countries are willing to accept it. The purpose of this study is to examine technical support role towards mitigating effects of computer anxiety on electronic assessment amongst University students in Nigeria and Cameroon. Therefore, the study extended Technology Acceptance Model and was validated using 102 responses collected randomly across universities in Nigeria and Cameroon. This study supports the body of knowledge by establishing that Computer Anxiety is an important factor which can affect University students regardless of their level of computer proficiency. The outcome of the proposed model indicated that when technical assistance is provided during e-Assessment, computer anxiety on majority of University students in Nigeria and Cameroon is reduced. The practical implication of this study is that students’ actual academic potentials may not be seen if education policy makers and University administrators do not always strive to ensure that all measures, including technical support that can reduce fear associated with use of computer for assessment, are introduced