Advance Magazine - Winter 2007/2008

O F F I C I A L P U B L I C AT I O N O F T H E A DVA N C E D F O O D S A N D M AT E R I A L S N E T W O R KVolume IV Number 1 Winter 2007/08

The “fullNelson”treatmentfor fruitdisease

INSIDE: Stressed bacteria are helping the food industry… page 8

Prof. Louise Nelson of the University of BritishColumbia has a newapproach to preserving fruit in storage. See page 9.

Prof. Louise Nelson of the University of BritishColumbia has a newapproach to preserving fruit in storage. See page 9.

The “fullNelson”treatmentfor fruitdisease

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Networks of Centres of Excellence

Ontario

Québec

British Columbia

Alber ta

Manitoba

Newfoundland &Labrador

Nova Scotia

New Brunswick

Saskatchewan

Prince Edward Island

42.2%

2,408

1,337192

231

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56

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23.9%

11.5%

10.8%

5.0%

2.8%

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NCE PERSONNEL NCE EXPENDITURES

Mobilizing ResearchExcellence, Creating ValueCanada has 14 Networks of Centres of Excellence (NCE). Each network builds partnerships between academia, industry and government to put newknowledge, research and technology to workto create a better Canada. Their work toucheseverything from disease care and engineering,to improving the quality of the food we eat and the water we drink. NCEs are helping to keepour forests flourishing and ease the impact of climate change. By involving thousands of talented young Canadians in their work, theyare training tomorrow’s scientific leaders and ensuring Canada’s continued role as a world science and technology leader.

The NCE Program supports thousands of researchers and highly qualified persons indozens of Canadian universities. The program partners include Canadian companies, provincialand federal government departments, and agencies from Canada, along with internationalpartners – making it a truly national and

international program.

In 2006, the networks stimulated outside cash and in-kind investments totaling almost $70 million, including more than $27 million by the participating private sector companies. With the program’s own investment, the totaldedicated to research, commercialization and knowledge transfer was more than $149 million.

www.nce.gc.ca

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Welcome

3AFMNet – ADVANCE 2007/ 08

Welcome to our fourth annual edition ofAdvance, the official publication of the AdvancedFoods and Materials Network (AFMNet).

For those of you who don’t know, AFMNet isCanada’s national food and biomaterials research net-work. Together, our researchers are presenting newideas and developing new biology-based technologiesto produce commercially viable, socially acceptablevalue-added products and processes that benefit allCanadians. Partnering with industry, government,not-for-profit organizations, and national and international research institutions, AFMNet has avision for a healthier Canada.

On the pages that follow, you will read howAFMNet researchers are examining the GLUT2 geneto gain insight into its role in carbohydrate consump-tion and how this may affect diabetes risk; arranginggel pores into an interconnected network that willrelease chemicals more consistently to ensure an evenrelease of medications; gathering protein- and gene-expression information to help regulators examine thecomposition and safety of genetically modified foodproducts; and studying how able Canada’s regulatorysystem is to cope with genetic tests available to consumers and new claims that may be made aboutsupplements, functional foods and nutraceuticals.

For the first time, you will also read about ourStrategic Transition and Application of Research(STAR) Program projects. In times of rapid technological advance-ment and growing global competition, it is critical that new productsand processes reach the market in a timely fashion. In February 2006,AFMNet introduced the STAR Program to fund research in emergingareas related to foods and biomaterials that benefit and are of relevanceto the social and economic health of Canada. The program is charac-terized by a rigorous, industrially focused arm’s-length review and arapid turnaround time, and is open to both AFMNet and non-AFMNet researchers, allowing us to capture untapped expertise withcommercial relevance.

Our cover story, detailing the work of Louise Nelson, is oneexample. Using DNA-macroarray technology, Nelson and her teamhave developed a way to detect fungal pathogens while apples are stillon the tree. They’ve also identified soil bacterial isolates that suppressthe growth of these pathogens and are ready to commercialize thedetection technology and soil bacterial isolates so they can be used ona larger scale. AFMNet is helping to make this possible.

We hope you enjoy this issue, encourage you to share it with oth-ers and, as always, welcome your feedback and ideas.

Sincerely,

Rickey Yada Murray McLaughlinScientific Director Chair of the Board of Directors

Volume IV Number 1 Winter 2007/08

The official publication of the Advanced Foodsand Materials Network

A publication to promote dialogue and understanding about sophisticated foods and materials research across Canada

Executive EditorsRickey Yada

Louise Jessup

Project Co-ordinatorAshley McCarl

Project ManagerLilian Schaer

EditorOwen Roberts

Associate EditorKim Waalderbos

Copy EditorBarbara Chance

DesignJnD Marketing

Financial ManagerJan Smith

Address correspondence to:Louise Jessup, Communications Manager

150 Research Lane, Suite 215Guelph, Ontario, Canada N1G 4T2

E-mail: [email protected]

Visit the AFMNet website:www.afmnet.ca

This publication was written by students in theSPARK program, Students Promoting Awareness

of Research Knowledge, at the University of Guelph in Ontario, Canada.

Publications Mail Agreement Number 40064673

Please return undeliverable Canadian addresses to:AFMNet, University of Guelph, 150 Research Lane,

Suite 215, Guelph, Ontario, Canada N1G 4T2

Dr. R

ickey Yad

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Fourth-year biological engineering student Ashley McCarl knows stress in bothengineering and emotional terms.As co-ordinator of this year’s Advance magazine,she hits the gym to burn off any stress. In her article on probiotic yogurt, sheexplores how foods can be structured to improve health. See page 7.

All contributors to Advance are part of the University of Guelph research writing program called Students Promoting Awareness of Research Knowledge (SPARK).

When researching this edition of Advance, SPARK writers found managing stress is vital for survival at many levels. For example, on page 8, they explain how bacteria take special measures to withstand harsh atmospheres.

So, how do SPARK writers manage stress? Read on...

In addition to his environmental studies, third-year arts and sciences student ArthurChurchyard keeps busy giving piano lessons and participating in student clubs. Tomanage his stress, he takes time to play with his feline family member, Simba.Arthur’s interest in regulations surrounding new foods led to his story on page 13about how Canada is coping with claims made about supplements, functional foodsand nutraceuticals.

Kaitlyn Little, a third-year public management student, likes to immerse herself inbooks, newspapers and magazines to reduce her stress. In this Advance issue,she satisfied her curiosity about why consumers yearn for certain foods with herarticle on a gene that could increase cravings for carbohydrates.Turn to page 11.

Fifth-year agricultural sciences student Sarah Van Engelen releases her stress bywhipping up cakes in the kitchen or sitting down to needlework. In this edition,Sarah discovered that even under stress, bacteria’s ability to survive humans’best cleaning efforts is actually helping the pharmaceutical industry. Find herstory on page 8.

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C O N T R I B U T O R S

Photos by Olivia Brown


C O N T E N T S

Strategic Transition and Application of Research

Cookies made with fat that’s good for the heart 6

Probiotic yogurt plays part in fighting ill effects of AIDS 7

Bacterial resilience is helping the food chain 8

New storage treatments to prevent rot in apples 9

Foods and Health

Research looks at fibre and its impact on the human gut 10

Linking higher carbohydrates and consumption patterns 11

Innovative model links breast milk and intestinal health 11

Consumer and Ethical Issues

Transgenic and conventional pigs compared for first time 12

Canadian regulations may be unprepared for novel foods 13

Materials

How to make peptides more economically feasible 14

Natural and synthetic gels get set for use in food, medicine 16

Cover photo by Tim Swanky

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Humans may be at their weakest pointin the checkout line at the grocery store.Amid the gossip magazines, batteries andchewing gum lurks a calorie counter’snightmare: racks of chocolate bars. Therecan’t be much harm in one little chocolatebar, can there? And isn’t there research say-ing chocolate is good for you?

The answer to both questions is yesand no. In moderation, sweets can be partof a balanced diet. And, yes, chocolate canbe good for you, especially dark chocolatewith its antioxidant properties. But foodswith large amounts of trans fat and saturat-ed fat are harmful, even in small quantities.And that’s what a lot of popular snackscontain.

But all is not lost for checkout-linejunkies.

Prof. Alejandro Marangoni of theUniversity of Guelph’s Department ofFood Science sits back as he recounts see-ing a Twix Bar production line runningsmoothly with his newly developed fat —one that contains no trans fat and is low insaturated fat, making it healthy for con-sumers. He saw it being tested on a line inGermany, home to some of the world’s bestchocolate.

“Now, that’scool,” he says.

In response tostrong consumerdemand for healthierfoods, companiesworldwide are reduc-ing or eliminatingtrans fats in many of their products. Doing sohas been a huge challenge for the food indus-try, which relies on solid fats such as trans fatsto maintain the texture, consistency andstructural properties of baked products.

To reduce trans fats, many food compa-nies turned to palm oil as the easiest alterna-tive to meet their needs. Palm oil (or palm fatas it’s called in Canada) is made from palmtree fruit and is a popular substitute becauseit’s cheap, is widely available and because itstays solid at room temperature in NorthAmerican climates. Most importantly, palmfat doesn’t contain trans fats. But it’s very highin saturated fat, which is also harmful.

“Trans fats are a public health concern,and now we’ve come up with a healthieralternative,” says Marangoni.

To make the new product, he firstlooked to the structure of trans fats. He knewthey formed a crystal structure at room tem-

perature, which created the necessary build-ing blocks to form the solid fat structure. Healso knew trans fats were cheap to manufac-ture and increased the shelf life of the finalproduct. Any new fat Marangoni developedwould have to keep pace with those proper-ties yet contain less saturated fat.

He began with standard oils — canolaand soybean — because they were pro-duced locally, making them easily avail-able. The challenge was to make the oilssolidify at room temperature. Part of thesolution, he found, was already widely usedin other areas of the food industry.

Emulsifiers such as egg yolk are com-monly used in food products to mixtogether two substances that wouldn’t oth-erwise combine. He was able to use a par-ticular emulsifier with his oil and watermixtures to make the liquids combine,solidify and produce a fat-like material.


Cookies madewith fat that’sgood for theheartResearcher developshealthy solid fat for industry baking needsBy Ashley McCarl Cookies are taking a

turn for the better healthwise, thanks

to a new processing fat created by

Prof. Alejandro Marangoniof the University

of Guelph.

Martin Schw

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Probiotic yogurt is now being used to help lessen side effects forAIDS patients in Africa, thanks to a Canadian researcher.

Prof. Gregor Reid of the Department of Microbiology andImmunology at the University of Western Ontario (UWO), took partin UWO’s inaugural mission to address the AIDS crisis in Africa in2003. When the students on the mission were in need of a projectthat would benefit their community of interest, Mwanza, Tanzania,Reid thought of tying in his probiotic work.

Probiotics are specific bacteria that in some cases can be added tofoods to enhance immunity and reduce the duration of illnesses suchas diarrhea. Research by Reid and Prof. Shari Hekmat of BresciaUniversity College at UWO had found their probiotic yogurt hasimmune-modulating properties. They wondered if the same proper-ties would have an effect on other conditions, including chronic diar-rhea in people with HIV/AIDS.

“The team has shown that local mothers in Tanzania can be taught to make probiotic yogurt, and some data show good health benefits from daily consumption,”says Reid.

Studies performed by UWO post-doctoral fellow Kingsley Anukam in Nigeriashowed that regular yogurt supplemented with Reid’s probiotic lactobacilli could improveimmunity and cure diarrhea. Meanwhile, in Tanzania, when the locally produced probiotic yogurt was consumed daily, it led to increased energy and fewer ill effects inpeople with AIDS.

Four years after the program began, the yogurt has become part of the supplemen-tary care given to more than 80 AIDS patients in Mwanza. Interns from UWO arrive inthe community three times a year to continue research and bring back messages to educate the UWO community.

The locally made probiotic yogurt has become widely popular in Tanzania and hashad such a high success rate that the World Bank — a group dedicated to eradicatingworld poverty — has decided to expand the project to Kenya.

Reid is now working with his UWO colleagues to create a probiotic yogurt that canbe given to people with other diseases linked to immune suppression. Graduate studentJamie Hemsworth and high school student Raj Bhayana, recipient of a Sanofi AventisBiotech Challenge award, have helped develop specific nutrient formulas for the yogurtand are about to begin human testing.

“If the trial shows promising findings, this food could be a great addition to currenttreatments and improve lives around the globe,” says Reid.

Funding is provided by AFMNet, the Canadian Institutes of Health Research, theLawson Health Research Institute, the Natural Sciences and Engineering ResearchCouncil and the Ontario Ministry of Agriculture, Food and Rural Affairs. �

Marangoni explains how it works: Theemulsifier encircles the oil molecules, formingsmall droplets. The droplets crystallize and bindto each other to produce a solid structure that isvery similar to the structure of bread and foams.Even though the material looks like a fat, itsstructure is much different from that of the tra-ditional fat crystal network, he says. The mate-rial works extremely well as a bakery shorteningand, according to food regulations, should bereferred to either as a light margarine or a short-ening alternative.

But the research didn’t stop there.Marangoni quickly learned that his novel mate-rial couldn’t be substituted for conventional fatsources at a one-to-one ratio in many foodproducts. So he set out to determine how muchof the new shortening alternative was needed toproduce the same taste, texture and consistencycharacteristics provided by other fat sources.

He has hired three recent University ofGuelph graduates to work with his shorteningalternative in typical baking applications to findthe substitution ratios for each use. They’re find-ing that the new shortening alternative does agreat job in cookies and creates a flaky pie crust.They’ve also discovered that the new fat canmake batters somewhat “stickier,” which is espe-cially useful for baking cookies that containchocolate chips. Marangoni says the new mate-rial reduces the number of chocolate chips need-ed by 40 per cent because fewer chips break orfall off on the assembly line.

“And that can save a company millions ofdollars,” he adds.

Excitement is high as the product is putthrough its final marketing and commercializa-tion test phases. With a patent pending,Marangoni expects his low-saturated-fat prod-uct will be available commercially later this year.If it passes shelf-life testing, the fat will hit themarket sooner in cookies and chocolate bars.

The Guelph food scientist worked in col-laboration with physics professor Stefan Idziakof the University of Waterloo. Graduates work-ing on this project are Sarah Langmaid, BrittanyHuschka and Carolyn Challacombe. Thisresearch is supported by AFMNet, and com-mercialization is led by Steve Bernet of CoagelCorporation. �

Probiotic yogurt:A tool for fightingill effects of AIDS

Probiotic yogurt:A tool for fightingill effects of AIDSBy Ashley McCarl

Yogurt has longbeen touted for its

health benefits.Now, research atthe University ofWestern Ontario

is proving this andmore as yogurt iseyed as part of a

treatment plan forpeople with AIDS.

Elena Elisseeva



Benefiting frombacterial biofilmsNovel products from micro-organisms could aid in drug delivery, producing car parts... and moreBy Sarah Van Engelen

When scientists in physics and microbiology teamed up tostudy how bacteria grow on surfaces and protect themselves fromexternal influences, one of their areas of focus was identifyingcomponents and products of the bacteria that could be used indeveloping novel products. As time goes on, that focus is gettingclearer.

It was University of Guelph physicist John Dutcher and thelate Terry Beveridge, a renowned Guelph microbiologist whopassed away this fall, who had immersed themselves in studyinghow bacteria live, multiply and function on different surfaces invarious environmental conditions. Bacteria form communitiescalled biofilms on almost any surface, and now Dutcher is carry-ing on with the research, exploring the components and productsof biofilms for use in other applications to benefit humans.

“Bacteria are highly evolved and sophisticated,” he says. “Weneed to take advantage of their resiliency.”

Learning how bacteria grow and form colonies on surfacessuch as counters, filing cabinets and food materials is only halfthe process. Studying how they stick to surfaces and how theyproduce a biofilm is another major part of understanding howbacterial resiliency can be used. Despite being stressed fromantimicrobial agents and scrubbed from surfaces, many bacteriaare able to survive humans’ best eradication efforts. To Dutcher, that’s what makes their properties so interesting.

One material of particular interest is the stiff, strong mesh ofsmall proteins and sugars that encloses the bacterial cell. Thismatrix allows the cell to withstand harsh atmospheres and largedifferences in pressure. Dutcher is trying to understand the struc-ture and improve the purification process of this biomaterial.

“It’s often very difficult to make an artificial material that isbetter than something produced naturally,” he says, “so we wantto make use of the special properties of the components ofbiofilms.”

The ultimate goal is to use these components in novel wayssuch as incorporating them into car parts, medical tubing andpharmaceutical encapsulates, says Dutcher, who believes manyopportunities are possible.

Another option is to extract the unique biological meshmaterial from the cells and incorporate it into other materials toachieve improved strength and mechanical properties for use incar parts or medical tubing, he says.

“The applications for biofilms are limited only by yourimagination.”

This project involves a large number of AFMNetresearchers: 10 different groups with 24 students and post-doctoral researchers. Funding is provided by AFMNet, theCanada Research Chairs program, the Canada Foundation for Innovation and the Natural Sciences and EngineeringResearch Council. �

Physics professor John Dutcher takes a break from his lab,where he’s exploring the components and products of biofilmsfor use in applications that will benefit humans.

Olivia Brown


When apples in the orchard pick up fungal pathogens, there’strouble down the line. When the fruit is placed in cold storage forat least six months, the pathogens cause the apples to rot. It’s a realproblem: fungal rot results in crop losses of five to 10 per cent eachyear. Fungicides can be used to control this problem, but they’refalling out of favour. So now, researchers are taking a new approach.

Prof. Louise Nelson of the University of British Columbia andPeter Sholberg of Agriculture and Agri-Food Canada’s Pacific Agri-Food Research Centre have developed a way to detect fungalpathogens while the apples are on the tree. They’re part of a teamthat has also identified environmentally sustainable soil bacterialisolates that act as effective biological control agents against the fun-gal pathogen.

“There is greater demand for environmentally sustainable post-harvest treatments to counter health concerns from the public aswell as to meet the needs of an emerging organic market,” saysNelson.

The pathogens that cause the post-harvest decay in apples areblue mould, grey mould and Mucor. Detecting these pathogens

before the apples go into storage means producers can limit post-harvest rot by keeping the affected apples out, she says.

The research team developed a DNA-based macroarray tech-nology that detects all three fungal pathogens and allows users to gointo the orchards and check for incidence of disease.

Here’s how it works. Samples are taken from leaves, blossomsand air, then analyzed to determine if the three pathogens are pres-ent. Using DNA macroarray technology, Nelson can pinpoint therelationship between high levels of pathogens present in the air,leaves and blossoms and the presence of post-harvest decay duringstorage.

In cases where storage is needed for apples that have beenexposed to the pathogen, the research team has developed an organ-ic solution — they’ve identified soil bacterial isolates that suppressthe growth of all three pathogens. Before the apples go into storage,they’re dipped into solutions containing the isolates to protect themfrom post-harvest decay. By the time the apples come out of coldstorage months later, the soil isolates decrease to a minimal level onthe apples. Treating the apples this way eliminates the need forfungicides and eases consumer health concerns.

Now, Nelson and Sholberg hope to commercialize the DNAmacroarray technology and the soil bacterial isolates, so they can beused on a larger scale.

“This research will be relevant across the country as it can elim-inate the negative effects of moulds in orchards as well as in otherfruits that are susceptible to the pathogens,” says Nelson.

Also involved in this project is post-doctoral researcherDanielle Hirkala.

This research is sponsored by AFMNet and Western EconomicDiversification Canada. �

Rot notEnvironmentally friendlystorage effectively beatsfungal pathogensBy Kaitlyn Little

University of British Columbia researchers (left to right) Daylin Mantyka, Prof. Louise Nelson and Danielle Hirkala

evaluate whether fungus has affected apples that have come out of cold storage.

Tim Swanky


Foods and Health

What you eat has a significant effect on thebacterial community in the intestine, or gut.Although it’s widely accepted that fibre is animportant part of a healthy diet, it’s still unclearhow fibrous foods, particularly those with wheatand oat bran, specifically contribute to intestin-al health.

Prof. Brent Selinger of the University ofLethbridge and Prof. Martin Kalmokoff ofDalhousie University are examining the role

of dietary fibre and prebiotics (carbohydrate polymers) in gut bacteria

and their link to gut health. The scientists are delving into

unknown research territory to understandthe gut-associated bacterial communityand how diet affects it. The intestinalcommunity contains more than 400species of bacteria, but only about 10

per cent have been well-studied to date. Thevast majority have not been previously iso-

lated or characterized in terms of theirmetabolic activities.

But now, Selinger and Kalmokoffare working at a molecular level byusing BioBreeding rats (bred andreared in an inbred colony) to teaseout how the bacterial community is

structured, how it changes inresponse to different dietary fibresources and how this affects theimmune state of this animalmodel. This model offers theadvantage of a relatively stable

bacterial colony passed frommother to offspring.

“Understanding how dietary fac-tors change the gut community mayallow us to design functional foods thatmay manipulate these complex micro-

bial communities and result inimproved health for the host,” saysKalmokoff.

The gut is host to trillions ofbacteria that may play a crucial

role in host immune function, resistance toinfection and nutrient processing. The bacteriaprovide nutrition to the cells lining the intestinethrough the production of short-chain fattyacids, by fermenting dietary material enteringthe intestine. This complex bacterial communi-ty appears to interact significantly with thebody’s immune system, which may have a majoreffect on physiological health.

In the fibre study, the BioBreeding ratswere fed various dietary fibres, including wheatbran, oat bran and prebiotics. The rats werethen examined to see what impact the dietaryfibre had on the bacterial populations in theirgut and on the immune state of the host. Theresearchers have found significant differences incolonic bacterial viability depending on thedietary fibre source and changes in specific bac-terial strains in response to fructans (sugars).

The knowledge gained by these studieshelps support regulatory decisions at HealthCanada, providing evidence to help evaluate theefficacy claims associated with fermentable car-bohydrates and prebiotics. The trials with prebi-otics also help the scientists understand theircontribution to gut health. Once all the datahave been gathered on the response of bacterialintestinal communities to various fibres and prebiotics, the researchers hope the knowledge will help consumers make informedfibre choices.

“Dietary fibre is an important componentof a healthy lifestyle,” says Selinger. “Thisresearch will allow us to guide consumers to buyhigh-quality sources of this fibre.”

Other members of the research teaminclude Prof. Julia Green-Johnson of theUniversity of Ontario Institute of Technology, Dr. Stephen Brooks and Dr. John Austin ofHealth Canada, Prof. Doug Inglis of theUniversity of Lethbridge and Prof. LisbethTruelstrup-Hansen of Dalhousie University.This project is sponsored by AFMNet,Agriculture and Agri-Food Canada, and Health Canada. �

Researcherslook to digestive-tractbacteria for greaterunderstanding By Kaitlyn Little

Gut checkBr

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Fray


Here’s more evidence to bolster thebreast-is-best argument: a University ofManitoba researcher says mother’s milkhas a powerful ability to improve gastroin-testinal health.

Prof. William Diehl-Jones, Faculty ofScience, has built a model to mimic theinner conditions of an infant’s digestivetract. The model combines a digestionprocess similar to that occurring in theinfant gut and a cell culture system that’slike the innermost layer of the intestinaltract. It shows that compounds in breastmilk protect and nourish tissues of theintestine by preventing damage fromoxidative stress (where molecules interferewith normal cell functions), a problemcommonly encountered by prematureinfants.

Diehl-Jones developed the infant gas-trointestinal model to determine howbreast milk compounds are absorbed byand protect digestive organs from damage.Now he’s working with collaborators todetermine which specific compounds aremost effective. He hopes they will ultimately be used to improve foods suchas baby formula.

“We can learn from nature to createsmarter foods and treatments for infants,”he says. “As we isolate breast milk com-pounds that improve intestinal and overallhealth, we gain the ability to add healthbenefits to formula.”

The model is one part of a cross-Canada study linking biochemists, physiol-ogists and nutritional scientists who aredelving into what compounds make breastmilk best.

Breast milk diminishes the levels of freeradicals (highly reactive molecules) in thedigestive tract and reduces damage to DNA,lipids and proteins in mucosal cells, whichline the gastrointestinal tract. These free rad-icals can cause an imbalance in the bodythat has been linked to premature infantdiseases such as necrotizing enterocolitis (aninflammatory bowel disorder) and a condi-tion called retinopathy of prematurity,which causes visual impairment and evenblindness in infants.

Diehl-Jones and his collaborators alsoplan to determine the extent to whichantioxidant molecules are absorbed into theinfant’s circulatory system, which could giveadditional benefits to the pre-term infant.

He is part of a team working with University of Manitoba human nutri-tional sciences professor James Friel toisolate the most beneficial breast milkcompounds, The isolated compoundshold potential for infant formula, butfuture studies will establish whether thebreast milk compounds that protect thepre-term infant from oxidative stresscould do the same in adult diets.

This work contributes to a multidis-ciplinary breast milk partnership thatincludes University of Manitoba profes-sors Rotimi Aluko, Miyoung Suh andTrust Beta of the Department of HumanNutritional Sciences, as well as Prof.David Kitts of the University of BritishColumbia and Jean-Claude Lavoie of theCentre hospitalier universitaire Sainte-Justine in Montreal. �

Breast milk forgastrointestinalhealthBy Arthur Churchyard

Linking higher carbsand consumptionpatternsBy Kaitlyn Little

Researchers at the University of Torontohave found that a gene dubbed GLUT2 mayhave a bearing on increased carbohydrate con-sumption.

Prof. Ahmed El-Sohemy and master’sstudent Karen Eny of the Department ofNutritional Sciences discovered that peoplewith a genetic variation in the GLUT2 geneconsume larger amounts of carbohydrates.

“Previous studies linking the GLUT2gene with diabetes have been inconsistent,”says Eny. “Now we’re examining whetherenvironmental factors such as carbohydrateconsumption are also associated with thisgene, which may partly explain the inconsis-tencies in previous gene-disease associationstudies.”

In the study, two populations are beingexamined: one group that’s been diagnosedwith diabetes and a second group of young,healthy subjects. Members of the diabeticgroup kept a record of their food intake forthree days to determine their carbohydrateconsumption. The second group completed aone-month food-frequency questionnaire toassess their consumption of a variety of foods.All participants had their DNA isolated tolearn if they carry the genetic variation in theGLUT2 gene.

It’s hoped the study’s findings will pro-vide insight into the role this gene plays in car-bohydrate consumption and how this mayaffect diabetes risk.

“We hope this approach, which considersboth environmental and genetic factors, willhelp in designing and conducting genetic dia-betes risk association studies in the future,”says Eny.

Other collaborators involved in thisstudy are University of Toronto professorThomas Wolever and graduate studentBénédicte Fontaine-Bisson.

Funding for this project is provided byAFMNet, the Canadian Institutes of HealthResearch and the Natural Sciences andEngineering Research Council. Eny alsoreceived the Julie Payette ResearchScholarship. �

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Babies who consume breast milk are getting more health benefits than previouslythought, according to new research.

Comparing transgenic andconventional organisms:

A new approachBy Matt Teeter

The safety of foods made fromgenetically modified organisms can bebetter evaluated with information aboutdifferences in gene expression and proteinproduction, say researchers at theUniversity of Guelph and McGillUniversity.

They believe that, along with datasuch as the carbohydrate, protein and fat content of foods, protein- and gene-expression information would helpregulators examining the compositionand safety of genetically modified foodproducts.

The data currently used by regula-tors are limited, says Guelph professorCecil Forsberg, Department of Molecularand Cellular Biology. That’s why aresearch group at Guelph is examininggene expression and proteins to provide amolecular picture that will expand thedetail of information available to regulators.

Forsberg, co-inventor of the trans-genic Enviropig, which better uses dietaryphosphorus, is working with colleagues tocompare conventional pigs with theirtransgenic counterparts. Much testing isrequired before these animals can beintroduced into the food chain.

He says any variation between thetwo could signal a potential health risk forhumans. And although it’s early, no sig-nificant differences have been found sofar.

“We haven’t found any physiologicaldifferences to keep us from moving aheadwith the transgenic pigs.”

Two teams at Guelph and McGill areat work on porcine and soybean projects,each with the goal of creating a databaseof gene expression or the combination ofgene expression and proteins that can beused by regulators when examining futurefood products.

The first team is examining proteinexpression in the major food tissues ofconventional and transgenic pigs. Thesecond team is looking at changes in geneexpression between conventional andtransgenic soybeans under different envi-ronmental conditions.

Much of the raw data have now beencollected, leaving the researchers to workon data processing and interpretation,creating the databases for use by regula-tors, scientists and others interested inthese areas, including bioinformation andbiotechnology companies. When thework is completed, regulators could usethe databases to assess the compositionand safety of new food products.

Team members on this projectinclude Profs. Serguei Golovan andDavid Chiu, technician Roy Meidinger,post-doctoral researcher Hatam Hakimovand graduate student Moshe Gadish ofthe University of Guelph, and Profs.Marc Fortin and Martina Stromvik ofMcGill.

This research is sponsored byAFMNet, industry partners and le Fondsquébécois de la recherché sur la nature etles technologies. �

Cecil Forsberg

The Enviropig created at the University of Guelph is being measured against its

conventional counterpart at the genetic level to determine if differences exist in

protein production.


Consumer and Ethical Issues


Unprepared for change Delays could deprive Canadians of nutrigenomics benefits By Arthur Churchyard

The fledgling science of nutrigenomics —the study of how nutrients and genes interact —may raise issues that catch the Canadian regula-tory system off guard, says a University ofOttawa researcher.

Prof. David Castle, Canada Research Chairin Science and Society, is studying how wellCanada’s regulatory system would be able tocope with new ways genetic tests may be provid-ed to consumers and new claims that may bemade about supplements, functional foods andnutraceuticals.

“Our concern is that nutrigenomics willraise new issues for regulators,” says Castle, “andwe’re not confident that the Canadian regulato-ry system, as it stands, can address all of theseissues.”

He points to the United Kingdom as anexample of why Canadian regulators should beproactive in preparing for new social issues raisedthrough advances in nutrigenomics. In 2001,U.K. consumer associations campaigned toexpress fears about a genetic test that hit the mar-ket after clearing what they believed were inade-quate regulations. Because of this perceived gap

in the regulatory sys-tem, the company withthe genetic test wasforced to stop sellingdirectly to consumers,regardless of whetherthe product offeredlegitimate benefits.

The benefits ofnutrigenomics — andthe harm of potentiallymisleading advice orunfounded claimsabout nutrigenomicproducts — need to bebetter measured andunderstood by regula-tors, says Castle, who isincorporating what’sbeen learned from theUnited Kingdom andother countries into hisC a n a d i a n - f o c u s e dstudy.

Nutrigenomics has received internationalattention because of its potential to capitalize oninteractions between people’s genes and thefoods or supplements they consume, he says. Itallows genetic tests to be developed that can pre-dict whether an individual is predisposed to cer-tain diseases.

Theoretically, it also means that disease-causing genes could be inactivated through bio-logical changes evoked by certain nutrients, orthat disease-fighting genes could be activated.

But the complexity surrounding nutrige-nomics has elicited varied reactions fromresearchers, biotech companies and government.That’s why Castle is studying print media articlesused by these stakeholders to understand differ-ences in how each group portrays nutrigenomics.

In another part of his study, a series of focusgroups held in partnership with the PublicHealth Agency of Canada will assess the under-standing of the public and health-care practi-tioners about nutrigenomics. The focus groupswill reveal how much Canadians already knowabout nutrigenomics, while tracking opinionshifts that occur as groups become moreinformed.

When his study wraps up in 2009, Castlewill offer recommendations on how Canadianregulations could be adapted to better addressgenetic tests and their distribution, as well ashealth claims about supplements, functionalfoods and nutraceuticals.

“We aren’t talking about creating new regu-lations,” he says. “Instead, we’re asking howcomprehensive our current regulations are and ifthey can be improved.”

Legal analysis for the study is being con-ducted by University of Alberta professors TimCaulfield and Nola Ries of the School of PublicHealth and Faculty of Law and Tania Bubela ofthe Department of Marketing, BusinessEconomics and Law. University of Ottawa col-laborators include Prof. Karine Morin and stu-dents Sarah Scott and Juliana Aiken of theDepartment of Philosophy.

This research is part of Genome Canada’sGenomics, Ethics, Environment, Economics,Law and Society initiative. Funding is providedby AFMNet. �

Martin Schwalbe

Shoppers in health foodstores face a sometimes confusing array of options.Researchers are looking into Canadian health food guidelines to help protect consumers.


Materials

Researchers findways to make peptides more feasible for food useBy Ashley McCarl

Peptides — short chains of amino acids —are effective at providing protection from harm-ful bacteria by attacking the bacterial cell andinterfering with vital functions. Medical practi-tioners are running clinical trials to study howpeptides might be administered to patients inplace of antibiotics to help cure bacterial infec-tions. Now, members of the food sector hope toalso use peptides in consumer products toimprove food safety. But before this can happen,peptides need to be more economically feasible.

To that end, Prof. Robert Hancock of theDepartment of Microbiology and Immunologyat the University of British Columbia has beenstudying three different ways to reduce the costof peptides. He’s drawing on his 20-year knowl-edge of what he calls “the small molecule withhuge potential,” having worked with the twosmallest known natural peptides: bovinebactenecin and bovine indolicidin.

“These peptides can easily be used in thefood-service sector,” says Hancock, “but theyneed to cost mere pennies to be feasible, andtherein lies the challenge.”

In the first approach, his research focus ison the length of the peptide chain. He hopes to

shorten the peptide to save money by reducingmaterials (amino acids), production and time.Traditional methods of producing the peptidesin the laboratory are labour- and time-intensiveand result in a single peptide costing more than$600. Using the 20 amino acids as buildingblocks and a peptide array robot could greatlyreduce the scale of peptide synthesis and cut thecost to less than a dollar per peptide, he says.

“The robot allows us to explore a muchbroader range of possibilities because the pep-tides are so much more economical.”

Using the robot, Hancock’s team has beenable to assemble peptides of eight to 12 aminoacids in length that are just as potent as the nor-mal 18-amino-acid-length peptides. Cataloguesof the peptides the team has created are record-ed in a database with details about their geneticmakeup and effectiveness at protecting againstbacterial infection. The list is now extensiveenough that the researchers can predict whatpeptide chain sequences will be most efficientwith 90-per-cent accuracy, saving time andmoney.

In the second approach, Hancock is part ofan investigation into using lactic acid bacteria tocreate peptides. Once a particular peptide is iso-lated, large batches of the bacteria are used toproduce the peptide on a larger scale at low cost.

The third approach involves synthesizingpeptides using potato plants and Arabidopsis, aplant from the mustard family commonly usedin genetic studies. The researchers hope to usethe plants in two ways to produce peptides. Inthe first, genes for the peptide are transferredinto a plant, which acts as a factory to synthesizepeptides that are later harvested (analogous tothe bacterial production method). The secondmethod modifies the plant to produce lowerpeptide levels for self-protection, which are thentransferred to food products created with theplant material.

Ultimately, finding economical ways toproduce peptides will make their incorporationinto food products more feasible, says Hancock.

“If peptides can easily be placed in both thefood and food packaging, and at low cost, theywill protect the consumer from the many food-borne bacterial contaminants that can make ussick today.”

Also involved in this research are Prof. JohnVederas of the University of Alberta and Prof.Santosh Misra of the University of Victoria. �

Keeping it short

University of British Columbia researcherBob Hancock is developing three differentways to produce peptides, which could beused in food and food packaging to boostconsumer safety.

The simple DNA of Arabidopsis,such as the one pictured here,promotes the species use ingenetic trials. Researchers at the University of BritishColumbia are using these plantsto produce peptides, a potentialnew bacteria-fighting agent.

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Materials

Biopolymers — natural and syntheticmaterials that are made of repetitive molec-ular structures — have lots of promise fortissue regeneration, food preservation andantimicrobial agent delivery. But what’s thebest way to make them work? That’s thechallenge facing AFMNet researchersdeveloping new biopolymers or “gels” thatare capable of releasing embedded benefi-cial compounds over time.

Making microstructured gels can bedifficult and often requires special equip-ment, says Prof. Dérick Rousseau of theSchool of Nutrition at Ryerson University.He thought there should be a better way,so he took a back-to-basics approach tobiopolymer manufacturing.

“We asked: ‘Can we make gels usingbasic things we already have in the lab?’The answer was: ‘Yes, easily and with verygood results.’”

With nothing more than a microscopeslide, biopolymer solutions and standardlaboratory equipment such as a centrifugeto spin and separate the components,Rousseau was able to generate thin films ofgel without difficulty. He can saturate the

film with a compound, creating a slow-release biopolymer that has a wide range ofapplications. Now he’s teamed withresearchers across the country to put thegels into action.

It’s the pores within gels that hold thechemicals to be released. But when mostgels are made, these pores are arranged ran-domly. As the gel dissolves, this random-ness often means the chemicals aren’treleased uniformly, which is a big problemif the gel is holding medication thatrequires an even release.

So Rousseau is collaborating withresearchers at Dalhousie University whoare developing a process to arrange thepores into an interconnected network thatwill release chemicals more consistently.

One application of these gels is thecontrolled release of antimicrobial agents.Network researchers at Dalhousie andAgriculture and Agri-Food Canada areinvestigating the use of gels containingantimicrobials derived from natural foodsources.

“It’s amazing how many compoundsnaturally have antimicrobial properties,”

he says. “Many are everyday food items likevanilla and rosemary, and we’re incorporat-ing their benefits into these gels.”

One promising gel uses allyl isothio-cyanate, a broad-spectrum antimicrobialfound in mustard. The gel will be tested inchickens to eliminate harmful gut bacteria.

This mix of basic and applied scienceis a big benefit to the biopolymer researchprogram, says Rousseau.

“One of our greatest strengths isresearch diversity. Our researchers span thecountry and all themes of AFMNet.”

The other researchers leading theseprojects are Profs. Allan Paulson, AmylGhanem and Lisbeth Truelstrup-Hansenof Dalhousie, Prof. David Pink of St.Francis Xavier University, Prof. MollyShoichet of the University of Toronto,Prof. Wankei Wan of the University ofWestern Ontario, Prof. Brian Amsden ofQueen’s University and Pascal Delaquis ofAgriculture and Agri-Food Canada.

This research is funded by AFMNet. �

Research that gelsBiopolymers find use in food and medicineBy Matt Teeter

Brandon Denard

Holes in the gels producedby bacteria are not evenlyspaced, as seen in Figure 1.Researchers are trying tomanipulate the structure tobe evenly spaced, as seen inFigure 2, so these gels canbe used to release chemicalsin pharmaceutical or foodapplications in a more uniform way.

Figure 1 Figure 2

Documents

Advance Magazine - Winter 2007/2008