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Issue 2, December 2014

PUB - Public Understanding of Biotechnology
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“Secret” technology turns local farm into green tea extract factory

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Only the actively-growing leaf tips of the Camellia sinensis plants grown on the Senteeko Tea Estate are harvested for the Plandaí Biotechnology Inc. extraction process. Image by ScienceLink.

Green tea is often punted as a health drink that contains valuable anti-oxidants. But Roger Duffield, president and CEO of Utah (US)-based company Plandaí Biotechnology Inc., says a cup a day may not keep the doctor away.

“The amount that actually gets into your body is minimal, and the addition of milk and sugar destroys what is available because it attaches to the molecules.”

Duffield says the problem lies in how the tea, and even commercially-available extracts of the tea, are processed.

“The industry cuts the leaves, puts them into containers and take them to a factory where they dry it. During the journey, the leaf sweats, burns and bruises, and quickly becomes limp. Once it’s limp it starts to sweat and once it sweats it loses the catechins.”

What is bioavailability?

 Bioavailability is a measure of how well the body absorbs molecules like pharmaceuticals or nutrients from the gut into the bloodstream.

Some molecules may be destroyed during the digestion process, so they may never reach the bloodstream and hence may never reach the body’s cells or their target – such molecules are said to have a low bioavailability.

Plandaí, he says, has found the solution in a “secret” piece of technology that apparently has its origins in Eastern Europe in the 1960s. Fast forward to today, the technology is ready for full-scale operations right here in South Africa.

“That farm was abandoned,” Duffield recalls. “The tea bushes were 20 feet high, the roads didn’t exist and the old tea factory had been ransacked with the roofs caved in and owls nesting in it.”

A few years and about 20 million US dollars later, the Senteeko estate in the Barberton District of Mpumalanga is now a lush and neatly-maintained tea farm hidden deep within hundreds of hectares of Sappi paper plantations, with Plandaí’s brand new, on-site agro-processing facility soon to ship its first batch of Phytofare™ Catechin complex from green tea.

What are catechins?

Catechins are anti-oxidants found in many plants, including green tea (unfermented Camellia sinensis). Various studies into the potential medical applications of these compounds have been conducted – see for instance Lim et al. (2013), Mandel et al. (2008), Haque et al. (2006) and Hou et al. (2005). References provided by Prof Anne Grobler.

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The Senteeko Tea Estate in the Barberton District of Mpumalanga is once again a flourishing farm that employs local workers. Above: The entrance to the Estate. Image by ScienceLink.

One of the most important discoveries that led Plandaí to this point was figuring out that the growing tea plants maintain a low “body” temperature. As such, the Senteeko harvest will be chilled to as close to plants’ natural temperature as possible, using a special cooling unit. This ensures that when the plants are shredded in the first processing step, they don’t turn into a “bog of green water”, as Duffield puts it.

The shredding step, which takes place in section 1 of the agro-processing plant, works a bit like a lawn mower that’s able to cut a hectare of grass into just one bucket – the volume of plant material is drastically reduced and no moisture is lost from the leaves. “Nobody’s ever done it; it’s amazing science and it took six prototypes to get here,” says Duffield.

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Workers spray herbicide to keep the Camellia sinensis tea plants free from weeds. Image by ScienceLink.

Section 2 is where the real magic happens. The temperature around the leaf cuttings shoots up to near boiling within a few seconds, and within another couple of minutes the cuttings are sheared down to sub-micron and nano sizes, with all the phytonutrients (including catechins) released in active, stable forms.

Next, the extraction and evaporation steps yield a powder of catechins that is 90-95% pure and contains eight different catechins in substantial quantities. After packaging, says Duffield, some of the powder goes to Prof Anne Grobler’s Preclinical Drug Development Platform (PCDDP) based at North-West University (in partnership with the Department of Science and Technology), for entrapment into their pioneering drug delivery system known as Pheroid®.

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Prof Anne Grobler and her team at the Preclinical Drug Development Platform (PCDDP) of North-West University (in partnership with the Department of Science and Technology), have pioneered a drug delivery system known as Pheroid®. Image courtesy of the PCDDP.
According to Grobler, Pheroid® acts as a protective barrier against the harsh and acidic environment of the human stomach, which might destroy the catechins. In this way, the Pheroid® delivery system could improve the bioavailability – preliminary results of a human clinical study looking into this are promising, and Grobler and her team hope to publish findings to this effect in 2015.

This particular Pheroid®-Phytofare™ catechin product will be sold as a nutriceutical under the name ph²™.

As for the Senteeko farm and processing facility, preparations are underway to add lemon and sweet wormwood (Artemisia annua) extracts. Duffield adds that Plandaí’s patented agro-processing technology could in fact be applied to the live leaves of almost any plant, including our local favourite Rooibos tea.
Listen to Roger Duffield talking about phytonutrients in lemons and his ‘lemon test’:

And, the farm could become even “greener” than it already looks, with plans for a hydro-power unit to be installed at its dam and for waste plant material to be used as fuel for the facility’s boiler.
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Plandaí Biotechnology Inc. plans to install a hydro-power unit at its Senteeko Tea Estate dam (above), and it intends using waste plant material as fuel for the facility’s boiler (below). Image by ScienceLink.

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Roger Duffield is president and CEO of Plandaí Biotechnology Inc. and Prof Anne Grobler is the director of the DST/NWU Preclinical Drug Development Platform (PCDDP). With thanks to Louise Willemse (CEO Dunn Roman Holdings - Africa (Pty) Ltd.), Etienne O’Connel (Senteeko Factory Manager) and James Goosen (Senteeko Farm Manager).

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