The natural hormone auxin is found in a liquid seaweed concentrate sold by Afrikelp™ and applied to roots and foliage as a natural biostimulant. This enhances root formation, improving nutrient uptake from the soil. The fast-growing brown kelp, Ecklonia maxima, found in the coastal region of Cape Town, contains remarkably high levels of auxin, an important plant hormone.

The active ingredients in natural biostimulants have the tendency to fluctuate due to it being derived from a natural plant species that is highly influenced by its surroundings. Factors include the phases of the moon, the tides and currents, temperature, salinity, nutrients, UV exposure, herbivores feeding on the kelp, the age of the plants, as well as the growth density. All these factors also have an impact on the auxin levels extracted from Ecklonia maxima.

“Due to the natural fluctuation of the auxin content in Ecklonia maxima, it is extremely important that we constantly measure the auxin content in each sustainably harvested batch and determine the levels in order to standardise the content in our products,” says Kobus Lindeque, Managing Director Afrikelp.

Plant hormones affect plant growth and yield production under different environmental conditions, including stress. Plants produce numerous hormones which include auxins and cytokinins. The effect of these two hormones depends on the ratio and final plant hormonal balance. Auxin plays a role in cell growth and cell expansion and is primarily produced in parts of the plant that are fast growing such as the stem. Interestingly, auxin is the only known plant hormone that is transported in one direction in a plant, that is from stem tip to roots. Therefore, the concentration of auxin is always higher at the top to control the overall shape of the plant. On the other hand, cytokinins are involved in cell division and produce new shoots and roots including delaying the natural aging process that causes the plant to die. Cytokinins together with auxins, are involved in repairing the plant if wounded. When concentration levels are equal between auxin and cytokinin, normal cell division will take place. If auxin concentrations are greater than cytokinin, then roots will form, but when auxin concentrations are lower than cytokinin, shoots will form. This demonstrates the importance of plant hormonal balancing.

Afrikelp Dunesha

“To address this fluctuation tendency, Afrikelp recently invested in new infrastructure such as a new Agilent triple quadruple liquid chromatography–mass spectrometry, or LC-MS device. The sole purpose of this investment is to improve the quality of our products.”

The liquid extract is tested extensively in Afrikelp’s laboratories in Cape Town. “We have increased our inhouse quality control capacity and are now able to do contamination, pH, conductivity, total polyphenols, moisture, rooting and germination assays tests locally in South Africa. This allows us to have a hands-on approach and provides us with the opportunity to be more efficient with our evaluations,” says Dr Naicker Production and Process Improvement Manager at Afrikelp.

In addition, the company also upgraded the growing rooms with state-of-the-art growing lights set at precise LUX readings to ensure that the trials conducted are accurate and unbiased. “Our temperature controlled growing rooms have been equipped with specific growing lights in the red and white wavelength range. This aligns with growing rooms used at other institutes and offers us the opportunity to provide our customers and clients with unbiased scientific data,” says Dr Naicker.

With the new infrastructure, the company can test the full plant hormone range in the kelp, including auxin and cytokinin, amino acids and other key components. This is important as it enables the company to get a precise and accurate measure of the plant hormones consequently allowing them to determine more effectively how their products will perform in the field.

This also aligns with future plans to become a world-renowned testing facility of plant hormones and extracts providing industries with accurate and meaningful data.

In addition to in-house QC, all liquid extracts will continue to be tested at the Technical University of Dresden in Germany to ensure that our analyses are aligned and consistent, thereby maintaining the highest quality products at all times.

For farmers, it means that they can be assured that what is written on the label is exactly what is delivered on farm.