Feb 19, 2015Scientists transform lettuce into ‘superfood’
A team of Rutgers University scientists has developed a lettuce product to compete with the nutritional value of blueberries, quinoa, almonds and kale.
According to information provided by Leon Segal, director of Rutgers’ Licensing and Technology Office of Technology Commercialization, the Rutgers lettuce is not that watery, flavorless sandwich topper that constitutes much of the public’s lettuce diet. Instead, the research team used tissue culture technology to create a colorful and nutritionally powerful red leaf plant they call Rutgers Scarlet Lettuce.
The new lettuce has more antioxidants and polyphenols, which are associated with preventing cancer and cardiovascular disease, than blueberries. It’s packed with fiber and low in calories, according to the scientists.
Most important, it tastes good – at least to Rutgers professor Ilya Raskin, who led the project.
With support from the National Institutes of Health, Raskin and his team from the School of Environmental and Biological Sciences set out about three years ago to see how they could boost the health value of the vegetable through “nutritional breeding.” They chose lettuce because it is an “ideal delivery vehicle,” as one of the most commonly consumed vegetables in domestic diets, Raskin said in a news release. It’s also a quick-growing plant that can be grown in warm and cooler months in parts of the country.
The new red leaf lettuce has twice the antioxidants and polyphenols of blueberries and cranberries, without the sugar. Regular consumption of antioxidants and polyphenols has been shown to protect against certain cancers, diabetes, cardiovascular diseases and inflammation. In October, capping three years of development, Rutgers Scarlet Lettuce was picked up by Coastline Family Farms of Salinas, California. The company began distributing it throughout North and South America. Marketed and trademarked as Nutraleaf, the new super lettuce comes in two varieties, a leaf and a romaine. Both are available locally at various Wegman’s supermarkets.
Why did the Rutgers scientists develop a new lettuce?
“Lettuce is the second most consumed vegetable after potatoes,” Raskin said.
Rutgers Scarlet is not a genetically modified plant. The researchers used what is called tissue culture technology. A plant is reduced to an individual cell; then millions are grown in a petri dish. The researchers select the ones that have the highest levels of the beneficial compounds they are looking for. In addition to being visually attractive, the deep burgundy Rutgers lettuce has only 10 calories per cup and is a good source of vitamins A and C, magnesium, iron and potassium.
Raskin, who grew up in Russia, received his Ph.D. from Michigan State University in 1984 and has been working at Rutgers for 25 years. He said non-GMO breeding of plants for nutritional benefit is “the next frontier” in food science. Rutgers Scarlet is “the first wave.” Rutgers Scarlet Lettuce is “our baby,” he said, “but hopefully there will be new lettuces to talk about in a year or so.”
He and his team are hard at work to make that dream a reality.
Antioxidants, phytonutrients and polyphenols have become familiar buzzwords to the health-oriented, and certain fruits and vegetables have achieved “superfood” status due to their high content of these beneficial compounds.
In the arena of produce with high antioxidant abilities, blueberries have topped the list. Blueberries are considered the gold standard due to their high levels of polyphenols, which are a subgroup of phytochemicals. Anthocyanins are a further subgroup of polyphenols and provide the pigments that color deep red and purple foods such as blueberries, acai berries, blackcurrants and red wine.
Research has shown these polyphenols to protect against diabetes, cardiovascular disease, memory loss, inflammation and cancer.
As blueberry availability is limited by its growing season, there are times when it is difficult to obtain the fresh product or the berries are priced at a premium – and blueberries are high in sugar, requiring limited consumption for people on restricted diets.
Is it possible for another commonly available fruit or vegetable to rival the high polyphenol content of blueberries? Raskin has selected lettuce, one of the most widely consumed and affordable vegetables and readily available year round in the United States.
Using red leaf lettuce, Raskin’s laboratory selected samples with the highest polyphenols. From there, using a non-transgenic process of tissue culture which replicates plant cells in a petri dish, then propagating in growth chambers and finally analyzing them for levels of polyphenols, anthocyanins and other antioxidants, Raskin developed a deep burgundy red lettuce that has elevated levels of polyphenols – two to three times that of blueberries.
The high polyphenol lettuce has been named Rutgers Scarlet Lettuce (RSL) – a tribute to Rutgers’ school mascot and color, the Rutgers Scarlet Knights. In addition to its high polyphenol profile, RSL has a low glycemic index, preventing spikes in blood sugar that foods high in carbohydrates or sugars, such as fruits and berries, can cause.
This was demonstrated through a trial in which diabetic mice given Rutgers Scarlet Lettuce showed significant decrease in blood glucose and insulin resistance compared to diabetic mice given regular lettuce. RSL is also high in chlorogenic acid, a polyphenolic compound known for its beneficial properties.
In addition to the study on blood glucose levels, Raskin’s team has conducted a 13-week feeding study where diet-induced obese mice fed a high-fat diet supplemented with RSL demonstrated improved glucose metabolism when compared to mice fed green lettuce or a high-fat diet without the RSL.
RSL is also being tested using an artificial gut model system that Rutgers uses to determine bioavailability of food to investigate whether nutrients make it through the digestive process. The system, known as TIM (TNO Intestinal Model), demonstrated that chlorogenic acid and quercetin glucosides from RSL are bioaccessible, and therefore are likely to be at least partially responsible for the beneficial health effects of RSL.
To introduce RSL to the market, Rutgers has patented and licensed RSL to Nutrasorb LLC, a Rutgers spinoff company that specializes in enhancing phytoactive compounds in foods.
Nutrasorb has granted a license to Shamrock Seeds as the exclusive seed dealer for RSL. Shamrock specializes in vegetable seed for commercial growers in the major salad growing regions in the United States and anticipates interest from U.S. growers. RSL seed is available to large and medium-size farms – there is a minimum purchase requirement – which must sign an agreement to use the licensed product. Commercial growers can obtain the RSL seed for growing as loose leaf lettuce or baby greens.
“We went to all the grower/shippers and produce companies in the area to announce this great development and talked to them about the opportunities that existed to be able to promote this new health benefit in lettuce,” said David Griffin, CEO for Shamrock. “We’re very excited by it and we look forward to getting it out in the marketplace.”
The produce companies that Shamrock is working with will be supplying it as whole head lettuce, bagged salad and bowls and through foodservice. The companies are not required by the agreement to use the Rutgers Scarlet Lettuce name; however, the cohesive factor that will help consumers identify the product is Nutrasorb’s “Food4Good” trademark, which will be on the product label.
The first company to launch this product will be Coastline Family Farms, a produce shipping company based in Salinas, California.
Coastline Family Farms has selected and trademarked the name Nutraleaf for the brand and will be the exclusive grower/shipper of whole head and artisan-pack Nutraleaf Burgundy Leaf Lettuce and Nutraleaf Burgundy Romaine for distribution throughout North and South America.
Its agreement with Shamrock allows for exclusive distribution of whole head lettuce for one year. Steve Henderson, Coastline Family Farms president, recognized the opportunity to enhance the company’s mission of providing health-promoting foods.
“We learned of the new high-antioxidant lettuce and Romaine, created by Rutgers, and decided we wanted to be a part of this trend in growing and marketing nutritionally superior products,” Henderson said.
Coastline’s product launch was Oct. 18, with official introductions taking place on both coasts. Coastline is also developing a nutrition-based marketing campaign, and its rollout will continue with test markets in major metropolitan areas.
Raskin’s lab is planning further research for increasing polyphenol and other nutrients in lettuces.