Loss of trans-resveratrol during storage and ageing of red wines
- Authors: Naiker, Mani , Anderson, S , Johnson, Joel , Mani, Janice , Wakeling, Lara , Bowry, Vincent
- Date: 2020
- Type: Text , Journal article
- Relation: Australian Journal of Grape and Wine Research Vol. 26, no. 4 (2020), p. 385-387
- Full Text: false
- Reviewed:
- Description: Background and Aims: The concentration of free trans-resveratrol in wine is expected to increase with storage because of hydrolysis of piceid (a bound form of resveratrol). This study measured resveratrol concentration in 16 Australasian red wines ranging from 1 to 6 years old, both initially and after a storage period of 16 months under ambient conditions. Methods and Results: During the study period, trans-resveratrol concentration decreased by an average of 76%. The decay in trans-resveratrol was first order over the tested range of wine source and vintage, with a mean trans-resveratrol bottle-storage half-life of 8 (±1 SD) months. Decay rate was remarkably independent of growing condition and year. Conclusion: The data suggest isomerisation of trans- to cis-resveratrol via residual enzymatic activity (rather than being catalysed by light or acid). Significance of the Study: In general, this may reduce the anticipated health benefits of the wine given that cis-resveratrol displays fewer health benefits than the trans isomer. © 2020 Australian Society of Viticulture and Oenology Inc.
Commercial lentils (lens culinaris) provide antioxidative and broad-spectrum anti-cancerous effects
- Authors: Kiran, Sudha , Johnson, Joel , Mani, Janice , Portman, Andrew , Mizzi, Trent , Naiker, Mani
- Date: 2021
- Type: Text , Journal article
- Relation: Legume Research Vol. 44, no. 2 (Feb 2021), p. 202-206
- Full Text: false
- Reviewed:
- Description: Background: Interest is growing surrounding functional foods, which provide health benefits in addition to nutritional value. In particular, there is a focus on pulse crops which contain high levels of polyphenolics, such as lentils. Methods: In this study, polyphenols were extracted from five L. culinaris varieties and characterized by both their antioxidant profile and cytotoxic activity. Result: Hulled varieties had a high content of secondary metabolites (>70 mg GAE/g), while all varieties demonstrated high antioxidant potential (1570-2020 Oxygen Radical Absorbance Capacity index). Furthermore, all extracts showed significant cytotoxicity against H9C2, HepG2, A549 and Calu-1 cancer cell lines. This recommends further investigation into the specific compounds present in L. culinaris, which could potentially be exploited for their anti-cancer activity.
Authentication using volatile composition : a proof-of-concept study on the volatile profiles of fourteen queensland ciders
- Authors: Wilson, Arron , Johnson, Joel , Batley, Ryan , Lal, Pawan , Wakeling, Lara , Naiker, Mani
- Date: 2021
- Type: Text , Journal article
- Relation: Beverages Vol. 7, no. 2 (2021), p.
- Full Text:
- Reviewed:
- Description: Although relatively small, the Australian cider industry has experienced significant growth in recent years. One of the current challenges in the industry is the lack of research specific to Australian ciders. Establishing baseline volatile organic compound (VOC) profiles of Australian cider is paramount to developing a better understanding of the industry. This understanding may ultimately be utilized for both the categorization and authentication of existing ciders, and the targeted modification of cider volatiles for the development and improvement of cider quality. This study utilized gas chromatography, coupled with mass spectrometry, to identify key VOCs present in 14 ciders sourced from four different manufacturers in Queensland, Australia. A total of 40 VOCs were identified across the ciders, with significant variation depending on the flavor and manufacturer. Principal component analysis indicated that the ciders were well-separated based on the manufacturer, supporting the prospect of using the volatile composition to discriminate between cider manufacturers. Furthermore, hierarchical cluster analysis highlighted the commonalities and differences in cider composition between different manufacturers, which may be indicative of the varying ingredients and manufacturing processes used to create the ciders. Future studies profiling the volatile composition of larger numbers of Australian ciders are recommended to support the use of this analytical technique for authentication purposes. Likewise, exploration of the relationship between specific processes and VOCs is recommended to fortify an understanding of how to optimize cider production to improve consumer satisfaction. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.
Attitudes towards science among senior secondary students in Fiji
- Authors: Naiker, Mani , Sharma, Bibhya , Wakeling, Lara , Johnson, Joel , Mani, Janice
- Date: 2020
- Type: Text , Journal article
- Relation: Waikato Journal of Education Vol. 25, no. 1 (2020), p. 57-72
- Full Text:
- Reviewed:
- Description: In order to investigate gender and ethnicity-based differences in scientific attitudes among Fijian students, the widely studied Test of Scientific Related Attitudes (TOSRA) was administered to 1401 senior secondary Fijian students (Years 11–13; approximately 15–18 years of age). Students generally had a positive attitude towards science overall in Years 11–13, with females showing a more positive attitude than males. By Year 13, the attitudes of females towards science had become more negative. The attitude of iTaukei students towards science started out lower than other ethnicities in Year 11 and increased during Year 12, before falling to below the starting attitude levels in Year 13. Fijian students of Indian descent generally had a positive attitude towards science that remained consistent throughout Years 11–13, with an increase in leisure and career interest in science in Year 13. A strong correlation was found between the ethnicity of a student and their first language. Continued science outreach programmes, particularly in Year 12, are important to achieve and retain scientific interest and attitudes among Fijian secondary students. © 2020, Wilf Malcolm Institute of Educational Research. All rights reserved.
Attitudes and experiences among first-year regional australian undergraduate students toward the study of chemistry
- Authors: Naiker, Mani , Wakeling, Lara , Johnson, Joel , Brown, Stephen
- Date: 2021
- Type: Text , Journal article
- Relation: Journal of University Teaching and Learning Practice Vol. 18, no. 4 (2021), p.
- Full Text:
- Reviewed:
- Description: Both attitude and previous experiences play a large role in shaping a student’s approach to and achievement in a given subject. Similarly, students’ enjoyment of their learning experiences is an important factor in determining their retention in their course of choice. Here, we explore the attitudes toward the study of chemistry amongst a cohort of first-year undergraduate students at a regional Australian university, including assessing these parameters at the beginning of their first term, the end of the first term and the end of their second term. In addition, metrics on the students’ experiences of studying chemistry were collected at the latter two timepoints. Generally, student attitudes toward chemistry were positive, as were student learning experiences in most instances. Two-step cluster analysis revealed the presence of two distinct clusters of students within the data, differing significantly in their overall attitude toward the study of chemistry. Students who had studied chemistry in Year 12 did not show any significant differences in their attitudes toward chemistry, when compared to students who had not studied Year 12 chemistry; however, their learning experiences in first-year chemistry were rated as being significantly more positive. We attribute this to their increased ability to engage with and successfully learn from the topic material presented in lectures and tutorials, as their previous exposure to the ‘language’ of chemistry may provide them with an advantage over chemistry-naïve students. © 2021, University of Wollongong. All rights reserved.
A cut above the rest : oxidative stress in chronic wounds and the potential role of polyphenols as therapeutics
- Authors: Johnson, Joel , Broszczak, Daniel , Mani, Janice , Anesi, Jack , Naiker, Mani
- Date: 2022
- Type: Text , Journal article , Review
- Relation: Journal of Pharmacy and Pharmacology Vol. 74, no. 4 (2022), p. 485-502
- Full Text: false
- Reviewed:
- Description: Objectives: The pathophysiology of chronic wounds typically involves redox imbalance and inflammation pathway dysregulation, often with concomitant microbial infection. Endogenous antioxidants such as glutathione and tocopherols are notably reduced or absent, indicative of significant oxidative imbalance. However, emerging evidence suggests that polyphenols could be effective agents for the amelioration of this condition. This review aims to summarise the current state of knowledge surrounding redox imbalance in the chronic wound environment and the potential use of polyphenols for the treatment of chronic wounds. Key findings: Polyphenols provide a multi-faceted approach towards the treatment of chronic wounds. Firstly, their antioxidant activity allows direct neutralisation of harmful free radicals and reactive oxygen species, assisting in restoring redox balance. Upregulation of pro-healing and anti-inflammatory gene pathways and enzymes by specific polyphenols further acts to reduce redox imbalance and promote wound healing actions, such as proliferation, extracellular matrix deposition and tissue remodelling. Finally, many polyphenols possess antimicrobial activity, which can be beneficial for preventing or resolving infection of the wound site. Summary: Exploration of this diverse group of natural compounds may yield effective and economical options for the prevention or treatment of chronic wounds. © 2021 The Author(s).
Attitude and achievement of first-year chemistry undergraduate students at the university of the South Pacific
- Authors: Johnson, Joel , Reddy, Pritika , Sharma, Sushita , Wakeling, Lara , Mani, Janice , Benveniste, Tessa , Naiker, Mani , Brown, Stephen
- Date: 2022
- Type: Text , Journal article
- Relation: Frontiers in Education Vol. 7, no. (2022), p.
- Full Text:
- Reviewed:
- Description: Student attitude toward chemistry may influence engagement and achievement in chemistry-related courses, however, equivocal results in studies conducted in Western countries to date indicate this relationship requires further investigation. In this study, we investigated the correlation between attitude toward chemistry and achievement amongst a cohort of first-year undergraduate students from The University of the South Pacific (USP). A cluster analysis was used to identify low- and high-achieving groups of students to further explore potential correlations. There was a positive correlation between the cognitive and affective components of attitude among low-achieving students, but not among high-achieving students. The cognitive component of attitude did not appear to be strongly correlated with achievement in students from either group, although the affective component was positively correlated with achievement. The single item most strongly correlated with student achievement was their response on the Worthless-Beneficial scale. One of the notable findings was the differences in the attitude-achievement relationship between low-achieving and high-achieving students, suggesting that combining these clusters of students into a single group for analysis may obscure underlying correlations. Chemistry educators should continue to target their teaching styles to cater to different learning styles and achievement levels of students, including cognitive and non-cognitive learning styles. Copyright © 2022 Johnson, Reddy, Sharma, Wakeling, Mani, Benveniste, Naiker and Brown.
Australian ethnomedicinal plant extracts promote apoptosis-mediated cell death In human hepatocellular carcinoma in vitro
- Authors: Kiran, Sudha , Chew, Guat , Johnson, Joel , Mani, Janice Sandra , Wakeling, Lara , Portman, Andrew , Naiker, Mani
- Date: 2021
- Type: Text , Journal article
- Relation: Pharmacognosy communications Vol. 11, no. 4 (2021), p. 210-213
- Full Text:
- Reviewed:
- Description: Introduction: Hepatocellular carcinoma (HCC) Is the leading cause of primary liver cancer with Its prevalence continuing to rise. Although the number of cases continues to rise In both developing and developed countries, prognosis remains poor due to a lack of successful treatments. Inspired by the prospect of developing complementary medicines for this condition, we explore several native Australian plants for anti-carcinogenic activity, especially against HCC. Methods: Cytotoxicity assays against HCC cell lines were conducted using various plant extracts. Biochemical profiling of the plant species was conducted for total phenolics and antioxidant capacity, while reverse transcription-polymerase chain reaction (RT-PCR) was used to determine the active apoptotic pathways. Results: Westringia fruticosa and Prostanthera ovalifolia (small-leaved variety) had high antioxidant (410 and 227 mg/g, respectively) and phenolic contents (72.7 and 42.7 mg/g, respectively). P ovalifolia (small-leaved variety) demonstrated the greatest cytotoxic activity against HepG2 cells (IC50 4.61 ± 0.98 pg/mL) followed by Solanum laciniatum leaves (11.79 ± 0.43 pg/mL) and fruit extracts (ripe, unripe) (14.85 ± 1.80 and 19 ± 1.32 pg/mL, respectively). RT-PCR results confirmed apoptotic events in HepG2 cells, exposed to ripe and unripe S. laciniatum fruit extracts, via caspase-3 pathway. The highest apoptotic induction occurred after 8 hr. Compared to unripe fruits, ripe fruits induced a greater level of apoptosis, as evidenced by a 73 % higher level of caspase-3 mRNA expression and 22 % lower IC50 value. Conclusion: With further investigation, these fruits may provide a valuable source of anticarcinogenic compounds for use as chemotherapeutic or complementary therapies.
Changes in anthocyanin and antioxidant contents during maturation of Australian highbush blueberry (Vaccinium corymbosum L.) Cultivars †
- Authors: Johnson, Joel , Steicke, Michelle , Mani, Janice , Rao, Shiwangni , Anderson, Scott , Wakeling, Lara , Naiker, Mani
- Date: 2021
- Type: Text , Journal article
- Relation: Engineering Proceedings Vol. 11, no. 1 (2021), p.
- Full Text:
- Reviewed:
- Description: The Australian blueberry industry is worth over $300 million, but there is limited information on factors influencing their chemical composition, particularly their ripeness and harvest stage. This pilot study investigated changes in total monomeric anthocyanin content (TMAC; measured using the pH-differential method) and total antioxidant capacity (TAC; measured with the cupric reducing antioxidant capacity assay) of four Australian highbush blueberry cultivars (Denise, Blue Rose, Brigitta and Bluecrop) at four time points and three maturity stages (unripe, moderately ripe and fully ripe). The TAC of most cultivars decreased by 8–18% during ripening, although that of the Blue Rose cultivar increased markedly. However, the TAC of ripe fruit from this cultivar also fluctuated markedly throughout the harvest season (between 1168–2171 mg Trolox equivalents 100 g