Nanoemulsions show potential for fighting cancer
antioxidants like lycopene may reduce the growth and spread of
cancer cells by over 70 per cent, according to researchers.
The research may lead to new and cost-effective ways of reducing the risk or improving the fight against certain cancers, if the results of early animal studies can be repeated in humans. Professor Robert Nicolosi told attendees at the IFT International Food Nanoscience Conference in New Orleans that nanoemulsions created using a high-pressure microfluidiser have led to the reduction in the size and growth of cancer cells in lab animals. Animals injected with neuroblastoma to promote the growth of cancer cells and then exposed to antioxidant nanoemulsions experienced a shrinkage in tumours by 65 per cent. "They had about 70 per cent tumour regression," said Prof Nicolosi from the University of Massachusetts. The majority of the results presented had yet to be published in peer-review journals and NutraIngredients.com has not seen the full data. Unlocking nanoemulsions Preparation of the nanoemulsions - oil-in-water or water-in-oil mixture with particles in the nanometre scale - is achieved using a microfluidiser. Water and an emulsifier like lecithin are mixed with the bioactive, such as an antioxidant and then poured into the microfluidiser. Many antioxidants are hydrophobic, or lipophilic, and so do not dissolve in water. The microfluidiser compresses the solution and forces it through tiny channels. These micro channels are then split and the solution forced to collide with itself at extremely high speed. The collision produces a stable nanoemulsion. Using the microfluidiser has enabled the production of stable nanoemulsions, making them commercially viable. Previously, the particles in nanoemulsions were found in a wide size range, from five nanometres to five micrometres. According to Scott McMeil, director of the nanotechnology characterisation laboratory at SAIC-Frederick, this made them less effective and less likely to gain US FDA approval. "Nanoemulsions have been around for several years, but they weren't very stable," he said. "But with a microfluidiser, it looks like it's overcoming the stability issues." Health potential Prof Nicolosi and his group have used the nanoemulsions to carry a range of bioactive compounds ranging from vitamin E to lycopene, from omega-3 fatty acids to plant sterols. But it's the bioactive with the anti-cancer potential that stole the spotlight here in New Orleans. A combination of antioxidants called the antioxidant synergy formulation (ASF) showed potential to reduce cancer cell growth. Furthermore, a nanoemulsion of curcumin was found to inhibit the spread of melanoma cancer cells by about 89 per cent, Prof Nicolosi told attendees. An added advantage of the nanoemulsions, said Prof Nicolosi, was that smaller quantities of the bioactives can be used to achieve the beneficial effects. This makes for cost-saving on the ingredients. Studies from Prof Nicolosi's lab have shown that the bioavailability and efficacy of vitamin E, for example, is increased when formulated in the nanoemulsions. The University of Massachusetts researchers are exploring the potential of the microfluidised Nan particles to formulate food; beverages, and nutritional supplements to reduce inflammation, and cholesterol, and thereby reduce the risk of chronic disease such as cardiovascular disease.
