Researchers intention to strengthen the U.S. rubber market by extracting latex from North American vegetation. This is important attributable to threats to Southeast Asia’s rubber provide. Their efforts deal with enhancing extraction effectivity and leveraging the distinctive properties of guayule latex. A stunning discovery additionally improves dandelion latex extraction.

The world’s pure provide is in danger, making essential developments important.

Amid the challenges of illness and excessive demand affecting the first pure rubber provide in Southeast Asia, scientists are working to ramp up the U.S. rubber market by advancing strategies to extract latex from two sustainable North American plant sources: a dandelion species and a desert shrub.

Researchers reported their strategies to enhance effectivity and enhance latex yield in two current publications, constructing upon a long time of analysis led by Katrina Cornish, professor of horticulture and crop science and meals, agricultural and organic engineering at The Ohio State University.

Cornish and colleagues have added specialised brokers in the course of the processing of the Taraxacum kok-saghyz (TK) dandelion and the guayule shrub to coax a better quantity of latex from each vegetation. Neither supply can merely be tapped – the strategy used on tropical timber that produce the one commercially out there pure rubber on the planet.

“We need to have efficient extraction methods for any and all alternative natural rubber-producing species, especially at a large scale,” Cornish mentioned. “And they have to be low-cost if you’re going to be able to compete in the tire market in the long term.”

The TK dandelion work was revealed not too long ago in Industrial Crops and Products, and the guayule analysis in Environmental Technology & Innovation.

The Importance of a Domestic Rubber Industry

Beyond tires, rubber has purposes in an estimated 50,000 merchandise. The want is pressing for a home pure rubber business: While the United States produces artificial rubber, it’s solely depending on imports for pure rubber. In 2019, 10% of the pure rubber provide was misplaced to illness – and the chance for transmission of South American leaf blight to Southeast Asia has elevated with the enlargement of direct airline journey between Brazil and China.

It just isn’t an overstatement, Cornish mentioned, to counsel that if leaf blight had been to make it from South America to Asia, the illness may wipe out many of the world’s pure rubber provide in brief order.

“And then we could see the collapse of the world’s supply chains and, subsequently, entire economies,” she mentioned. “We’ve concentrated an entire global industry around a tropical plant. But TK dandelion and guayule are sustainable and can grow in temperate conditions.”

Unique Qualities of Guayule Latex

Guayule latex comes from generalized cells within the shrub’s bark. Extracting the latex includes grinding up the bark to interrupt open its cells and launch latex particles into what Cornish calls a “milkshake.” A sequence of washing and spinning cycles follows to separate the latex from different stable materials – and with every centrifugation step, some latex is misplaced.

The analysis crew discovered that including chemical substances known as flocculants to the milkshake helped bind different stable supplies collectively and separate them from the latex, successfully chopping the washing cycles in half and enhancing the general latex yield. The addition of 1 substance doubled the out there latex and that yield was elevated by 12-fold when a creaming agent was added for purification.

“By adding flocculants, latex extraction is more efficient and clean,” mentioned first research creator Beenish Saba, a postdoctoral researcher in meals, agricultural, and organic engineering at Ohio State. “We found specific flocculants that work best at improving the quality of latex extraction and reducing the time it takes.”

The research additionally confirmed that feeding the remaining solids again by the processing system enabled the extraction of much more latex and in addition lowered the environmental footprint of the whole operation, Saba mentioned.

Guayule accommodates a very engaging high-performance latex that’s stronger and softer than every other identified polymer, Cornish mentioned, which means extra filler could be added in manufacturing with none lack of its helpful properties. She used guayule latex to develop the primary hypoallergenic medical glove to dam each radiation and pathogens.

Innovative Extraction from TK Dandelion

Though TK dandelion latex is produced within the plant’s roots, the extraction course of is analogous – the roots are trimmed, blended right into a slurry, and filtered to take away stable chunks of plant materials and dust. Latex floating on the highest of the remaining liquid is slurped up with a pipette and rinsed as much as thrice for purification, after which dried.

A little bit of serendipity led to the development to this extraction methodology. First creator Nathaniel King-Smith, a graduate pupil in Cornish’s lab, discovered that processed samples sitting within the lab for 3 months had considerably extra latex floating on their surfaces. An evaluation confirmed that heavy divalent cations, like magnesium, certain to the latex particle membranes weighed down the particles – till the connection finally collapsed.

The crew discovered that including EDTA, a chelator that binds to divalent cations, to processing the dandelion roots allowed for the extraction of greater than twice as a lot latex than was extracted with out the addition of EDTA.

“Our question was, how can we free up the heavy fraction without waiting three months for rubber particles to suddenly become lighter and float?” King-Smith mentioned. “We found that the extra latex yield after months of storage could be achieved immediately in a standard extraction just by adding EDTA before spinning.”

Future Prospects and Collaborations

The use of EDTA additionally elevated the gel content material of the extracted latex as soon as it was dried – helpful data for potential manufacturing by industries which might be in search of higher-gel rubber, he mentioned.

EDTA could develop into relevant to latex extraction from guayule, although Cornish mentioned her lab hopes to accomplice with flocculant chemists who may assist additional refine that course of. She has been planting, harvesting, and extracting latex from TK dandelion for over a decade in Ohio and has a greenhouse filled with guayule on Ohio State’s Wooster campus, the place she hopes to sooner or later construct a full-scale latex processing plant.

“We are working on a small scale and focusing on premium latex markets where you can make something of great value with minimal materials so that we can fund expansion,” she mentioned. “And in the meantime, we’re making extraction more efficient so we can make the material clean and pure.”

Reference: “Extractable latex yield from Taraxacum kok-saghyz roots is enhanced by increasing rubber particle buoyancy” by Nathaniel King-Smith, Kristof Molnar, Joshua J. Blakeslee, Colleen M. McMahan, Aswathy S. Pillai, Meirambek Mutalkhanov, Judit E. Puskas and Katrina Cornish, 28 October 2023, Industrial Crops and Products.
DOI: 10.1016/j.indcrop.2023.117698

“Base-dependent flocculant treatment improves the extraction of latex from guayule” by Beenish Saba, Cindy S. Barrera, David J. Barker and Katrina Cornish, 4 October 2023, Environmental Technology & Innovation.
DOI: 10.1016/j.eti.2023.103388

This work was supported by the National Institute of Food and Agriculture.