The company said the development is expected to decrease the cost of making high purity Reb A extracts by as much as 60%. The new strain, which GLG Life Tech calls “Super RA” or “SRA,” has more than triple the naturally-occurring amount of Reb A glycosides when compared to the conventional stevia varieties in the marketplace today.
GLG Life Tech said that far less raw material would be needed to produce the same amount of high purity Reb A extract using the new variety. Other cost savings, such as lower amounts of solvents, less machine time and lower labor costs involved in handling the lesser bulk of the new, high potency variety all figure into the ultimate cost saving calculation, the company said.
GLG Life Tech released assay details of its testing on the new variety. The tests show that The SRA leaf contains 21% total steviol glycosides (TSG), which the company says is double today’s average leaf content of 10%-11% TSG. This big jump in TSG content is the primary factor in the tripling of Reb A content. Additionally, the percentage of TSG that comprises Reb A is 76%, compared to an average value today of about 50%. The company said that on a dry weight basis, this means that Reb A is present in the SRA leaf at levels of about 16% (relative to total leaf weight), compared to less than 6% for conventional leaf. Furthermore, the SRA variety derives from GLG’s Huinong line of stevia plants, which, in addition to producing high-Reb A and high-TSG, also carries traits of high leaf or biomass yield (typically 30%-40% bigger than conventional plants) and high disease resistance.
Other breeding successes
This isn’t the first milestone in GLG Life Tech’s breeding program. As formulators have looked for ways to deal with the taste drawbacks of whole stevia or Reb A extracts, they have increasingly turned to other glycosides, such as Reb C or even Reb X. These sought-after glycosides - which lack the bitterness of best-known glycoside Reb A - typically occur in such low concentrations in the leaf that processing costs to extract and purify them on a commercial scale are “virtually prohibitive”, it claimed. The company recently announced it has developed another new stevia variety that can make a plant-dervied Reb C extract commercially viable.
“Reb C, at the low levels at which it previously occurred, is especially costly to process to a high level of purity, and there has been insufficient supply to meet market demand. But with GLG’s development of the H6 strain and its much higher natural concentrations of Reb C, these cost and processing challenges will be greatly mitigated, thus enabling production of high-purity Reb C at costs comparable to that of high-purity Reb A and at volumes the market requires,” the company said.
“This is an astounding leap forward in the natural, non-GMO agronomic development of the historically scarcer steviol glycosides; one that GLG expects will have a major impact on the stevia market as it exists today.”
The H6 stevia seedlings - developed via patented non-GMO breeding techniques by GLG’s wholly owned Chinese subsidiary Anhui Bengbu HN Stevia High Tech Development Co. Ltd - contain Reb C concentrations “verging on 7%” compared with the average of <1%.