Maria Stewart

Dr. Maria Stewart


Research Focus & Metrics

Academic Career Length

15Years (2012-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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2 July 2015 in Nutrients
Verified
Journal Article
Open access
PDF file
AZAlison M. Zenel
Alison M. Zenel
MSMaria Stewart
Maria Stewart
The present study compared the effects of three rice cultivars on postprandial glycemic control and appetite. A single-blind, randomized, crossover clinical trial was performed with 18 healthy subjects, nine males and nine females. Three treatments were administered at three separate study visits: commercially available conventional white rice (short grain), specialty high amylose white rice 1 (Dixiebelle), and specialty high amylose white rice 2 (Rondo). Postprandial capillary blood glucose, venous blood glucose and insulin measurements, and appetite visual analog scale (VAS) surveys were done over the course of two hours. The capillary blood glucose concentrations were significantly lower for Rondo compared to short grain rice at 30 min, and for Dixiebelle and Rondo compared to short grain rice at 45, 60, and 120 min. Capillary blood glucose area under the curve (AUC) was significantly lower for Dixiebelle and Rondo compared to short grain rice. Subjects were significantly more hungry at 30 min after Dixiebelle intake than Rondo intake, but there were no other significant effects in appetite ratings. The present study determined that intake of high amylose rice with resistant starch (RS) can attenuate postprandial blood glucose and insulin response in comparison to short grain rice.

7 January 2013 in Nutrition Reviews
Verified
Journal Article
Closed access
PDF file
MSMaria Stewart
Maria Stewart
NSNatalia M Schroeder
Natalia M Schroeder

1 February 2012 in Journal of Medicinal Food
Verified
Journal Article
Closed access
YCYu-Ting Chiu
Yu-Ting Chiu
MSMaria Stewart
Maria Stewart
Konjac glucomannan (KGM) is a dietary fiber found in Amophophallus konjac. This fiber is fermentable based on human and animal trials, but short-chain fatty acid (SCFA) production profiles are unknown. The aim of this study is to characterize the digestibility and fermentability in vitro of two preparations of KGM, to better understand how KGM improves human health. Konnyaku (yam cake made of A. konjac), isolated KGM, inulin, and guar gum were subjected to in vitro digestion and in vitro fermentation. Fermentation samples were removed at 0, 4, 8, 12, and 24 hours for gas volume, pH, and SCFA measurements. Acetate, propionate, and butyrate were measured with gas chromatography. Results of the in vitro digestion confirm that KGM and konnyaku are resistant to degradation by digestive enzymes. Gas production in fermentation vessels containing konnyaku and KGM was lower than for inulin from 8 to 24 hours. Both samples produced SCFA concentrations similar to guar gum, which favored acetate and propionate over butyrate production. This study is the first to characterize SCFA production by KGM in its isolated form and in food form. Fermentation patterns presented in this study may provide a mechanism for the previously published health benefit of konnyaku and KGM.

1 June 2015
Verified
Open access
Jinan BannaJinan Banna
Jinan Banna
MLMeng-Fen Grace Lin
Meng-Fen Grace Lin
MSMaria Stewart
Maria Stewart
MFMarie K Fialkowski
Marie K Fialkowski
Fostering interaction in the online classroom is an important consideration in ensuring that students actively create their own knowledge and reach a high level of achievement in science courses. This study focuses on fostering interaction in an online introductory nutrition course offered in a public institution of higher education in Hawai‘i, USA. Interactive features included synchronous discussions and polls in scheduled sessions, and social media tools for sharing of information and resources. Qualitative student feedback was solicited regarding the new course features. Findings indicated that students who attended monthly synchronous sessions valued live interaction with peers and the instructor. Issues identified included technical difficulties during synchronous sessions, lack of participation on the part of fellow students in discussion and inability to attend synchronous sessions due to scheduling conflicts. In addition, few students made use of the opportunity to interact via social media. While students indicated that the interactive components of the course were valuable, several areas in which improvement may be made remain. Future studies may explore potential solutions to issues identified with new features to further promote interaction and foster learning in the course. Recommendations for instructors who are interested in offering online science courses in higher education are provided.