Agro-waste could provide nano-fibres for probiotics encapsulation

Waste fibres from the agricultural and food processing industry could be used for the nano-encapsulation of bioactives such as probiotics, according to new research.

The study, published in the Journal of Agricultural and Food Chemistry, explored the potential for using soluble dietary fibre from agro-wastes such as okara (soybean solid waste), oil palm trunk, and oil palm frond (leaf and foliage) for the nano-encapsulation of the probiotic Lactobacillus acidophilus.

“In view of sustainable development, there is aggressive research in transforming the high-volume wastes which cause disposal and environmental problems to natural resources for the production of sustainable products, such as liquid bio-fuel, fertilizer, fodder, and even human food products,” said the research team, led by Min-Tze Liong, from the School of Industrial Technology at the Universiti Sains Malaysia, Malaysia.

“To our knowledge, this is the first study to investigate the potential of agro-waste fibres as functional nano-materials, which may provide some indications for a potential alternative encapsulation technique for the selected beneficial bacteria,” they added.

Waste products

Liong and colleagues noted that oil palm and soybean are the two largest oil crop commodities in the world, cumulatively contributing more than half of the world’s total oil production of 163.9 million tonnes in 2009.

“The expansion of these commodities is resulting in overproduction of biomass wastes, because only a small fraction of the plants is commercially valuable,” they explained.

The authors said that around 90 per cent of the oil palm is made up of trunk, leaf (frond), and other fibrous wastes which contain large amounts of soluble fibres such as lignin, cellulose, and hemicelluloses. They added that okara, the main solid waste from soy- and tofu-processing industries, contains up to 49 per cent total dietary fibre.

Liong and co-workers suggested that such waste could be used in the production of other food and nutraceutical products in order to reduce waste production in the food industry.

Encapsulation

The authors noted that the incorporation of the beneficial bacteria is often challenged with the preservation of viability during processing, storage, and gastrointestinal transit.

Previous researchers have used encapsulation techniques to enhance the delivery of probiotics into the gut. The authors said that the use of nano-encapsulation techniques may offer many advantages compared to other encapsulation methods.

They added that biopolymers that are biocompatible, biodegradable, and nontoxic “are favoured for nano-encapsulation of bioactives for food and biomedical applications.”

The new study built on a previous study suggesting that agrowastes from oil palm and soybean contained dietary fibers that could be spun into nanofibers using electrospinning technology, by developing and evaluating an agrowaste-based nanofiber encapsulation of the probiotic Lactobacillus acidophilus.

The research team produced nanofibres from the soluble dietary fibre fractions of okara and oil palm which showed “good potential as a nano-encapsulant for probiotics.”

“Viability studies showed good bacterial survivability of 78.6–90 per cent under electrospinning conditions and retained viability at refrigeration temperature during the 21 day storage study,” said Liong and colleagues.

Source: Journal of Agricultural and Food Chemistry

Published online ahead of print, doi: 10.1021/jf2009342

“Agrowaste-Based Nanofibers as a Probiotic Encapsulant: Fabrication and Characterization”

Authors: W-Y Fung, K-H Yuen, M-T Liong