Screening Ontario Grown Onion Varieties for Antioxidant Properties

Agricultural products are in great demand in nutra-pharmaceutical and biomedical industries due to their potential health benefits to humans. Among all vegetables, onions are the most widely and largely consumed vegetable. Onions are rich in phenolic such as flavonoids, and anthocyanins. Flavonoid has the potential to be antioxidant, antibacterial, anti-inflammatory and anticancerous. Studies indicate that the decline in cardiovascular diseases, breast cancer, diabetes, inflammation and osteoporosis could be linked to the consumption of flavonoid based foods. In this study, we screen Ontario grown onion varieties namely Stanley, Safrane, Fortress, Lasalle and Ruby Ring for their antioxidant properties, and isolate the flavonoids present in them and the best Ontario grown onion variety was chosen for developing functional food traits. Extraction with solvents, low polarity water and supercritical carbon dioxide produced flavonoids such as kampferol, quercetin, myricetin, isorhamnetin from all the 5 onion varieties. High Performance Liquid Chromatography analysis of the extracted flavonoids showed the presence of sulfur containing compounds. The antioxidant efficacy of these extracts evaluated by oxygen radical scavenging assays, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) assays provided a better understanding of the nutrient profile of the Ontario grown onion varieties. Identification, enhancement and development of market quality traits such as antioxidants properties of Ontario-grown onions enhances their marketability as nutraceutical products, as natural antibiofilm coating agent for improved shelf life of packaged food and as a preservative in processed food.


Design and Development of an Internet of Things (IoT) based Poultry Monitoring Telemetry System

Simranjit Shahni & Suresh Neethirajan

Globalization and ecological pressures have increased the emergence of novel infections and global pandemics in poultry sector. This means that not only livestock such as poultry and egg laying birds are at increasing risk of contracting new and difficult to control diseases, but the people who care for them are as well. This is a game changer brought on by the speed of evolution of disease organisms. To meet the current and emerging challenges of poultry and egg laying birds’ disease surveillance, diagnostics and control, it is imperative that a paradigm shift occurs in how diseases are identified. This shift involves predicting diseases even before it occurs and preventing them through enhanced surveillance tools. Canadian poultry and livestock sector is under heavy pressure to improve its biosecurity protocols and enhance animal welfare. Canadian Food Inspection Agency is seeking new tools to enable rapid, real-time and on-farm monitoring of diseases, disease causing factors, and record keeping. The development of affordable; nanotechnologies based wireless networks that can be used for accurate real-time monitoring of the poultry farm environment is being addressed.  The BioNanolab of the University of Guelph has developed a real-time warning system for monitoring multiple environmental factors such as carbon dioxide and ammonia concentrations, temperature, humidity, water level, and activity of the chicken birds in the poultry farm using a user-friendly mobile ‘App’ and a wireless telemetry network architecture. The development of a framework and integration of wireless sensors and mobile system network to control and remotely monitor environmental parameters in the poultry farm provides as a promising biosecurity tool.

Rapid Detection of Food Allergens by Microfluidics ELISA Based Optical Biosensor

The risks associated with the presence of hidden allergens in food have increased the need for rapid, sensitive, and reliable methods for tracing food allergens in commodities. Conventional enzyme immunosorbent assay (ELISA) has usually been performed in a centralized lab, requiring considerable time and sample/reagent consumption and expensive detection instruments. In this study, a microfluidic ELISA platform combined with a custom-designed optical sensor was developed for the quantitative analysis of the proteins wheat gluten and Ara h 1. The developed microfluidic ELISA biosensor reduced the total assay time from hours (up to 3.5 h) to 15–20 min and decreased sample/reagent consumption to 5–10 μL, compared to a few hundred microliters in commercial ELISA kits, with superior sensitivity. The quantitative capability of the presented biosensor is a distinctive advantage over the commercially available rapid methods such as lateral flow devices (LFD) and dipstick tests. The developed microfluidic biosensor demonstrates the potential for sensitive and less-expensive on-site determination for rapidly detecting food allergens in a complex sample system.

Ultra-Sensitive Detection of Breast Cancer Biomarkers Using Time-Resolved FRET and Quantum Dots

Breast cancer is defined as a malignant neoplasm that occurs at or around the breast issue area. This disease affected 25,000 women last year in Canada and claimed the lives of 5,000 women. These numbers represent 26% and 14% of all new breast cancer and deaths, respectively, for Canadian women in 2015. These numbers do not tell us the amount of lives that were affected due to the disease, which can go into the hundred thousands. Here we develop a multiplexed microfluidics chip that accurately detects miR-195 and let-7a in human serum samples. MicroRNAs (miRNA) are small non-coding messenger RNA that are derived from messenger RNA. These small robust RNAs are looked at as precursors to many different diseases including breast cancer. Both miR-195 and let-7a have been shown to increases in concentration in human serum samples during cancer and decrease in concentration within tumor cells during cancer. To effectively measure miRNA concentration in blood with minimally invasive techniques, the developed microfluidics chip detects the miRNA levels from human blood using time resolved-förster resonance energy transfer. The detection mechanism uses a DNA zipper that binds the miRNA with an 8 base pair (bp) DNA supporter sequence and a complementary DNA sequence. When the supporter, complementary and miRNA sequences bind together a terbium-cryptate molecule excites a quantum-dot (710 nm for let-7a and 655 nm for miR-195) and the fluorescence is measured. Detection limits of the miRNAs are 10 picomolar, with a dynamic range of 10 nM to 0.1 nM when measured with microfluidics chips.

Development of Bulk Acoustic Wave Sensors for Detection of Melamine in Milk and Infant Formula

Melamine, a synthetically produced compound, is considered as an illegal adulteration and also a contamination in dairy products. Food contaminated with the trace amount of melamine can result in the urinary calculi and the kidney failure. Health Canada has set a maximum tolerable limit of 0.5 ppm in infant formula and 2.5 ppm in other food products. Different techniques have been employed. However, they need expensive laboratory facilities, which is not applicable for the field test application. Therefore, there is a need for a real-time detection of melamine.

In this project, a Bulk acoustic wave (BAW) sensor was employed to detect trace amounts of melamine in the milk. Using thiolation chemistry, the gold electrode surface was modified to provide selective sensing. A change in mass loading on the crystal, results a shift in resonant frequency. By monitoring the resonant frequency versus the change in the melamine concentration, sensor specification is obtained. The preliminary results show that there is a decreasing trend of the resonant frequency with increase in the concentration of melamine. Bulk wave acoustic sensor has the potential to detect food adulterants such as melamine with higher specificity and sensitivity. The sensor will significantly aid the management of dairy products to preserve quality and thus quality of processed foods made from milk.

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