Phytogenics as a natural alternative to antibiotics

18-02-2014 | | |
The essential oil turmeric contains ar-turmerone, a phytogenic compound that can exert antioxidant effects.
The essential oil turmeric contains ar-turmerone, a phytogenic compound that can exert antioxidant effects.

With antibiotic growth promoters (AGP) being reduced in leading countries all over the world, the interest for natural alternatives rose. New strategies come with new principles… How can swine production benefit from ‘quorum quenching’ and ‘ar-turmerone’?

By Martin Brötel, Delacon, Steyregg, Austria

The rising global population comes with an increasing demand for food such as meat as a source of protein. Other than diminishing farm land for agriculture use to produce food, consumer concerns about food quality and safety are key issues. Therefore, the resulting challenge for the international feed and animal husbandry industry is to realise sustainable global livestock production strategies for efficient production and safe food for the consumers.

Since 2006 antibiotic growth promoters (AGP) in livestock feeding have been prohibited in the European Union. South Korea is one of the first Asian countries that restricted the use of AGPs in 2011. Contrary to the valid use of antibiotics for prevention and treatment of pathogenic infections to prevent diseases, animals are still administered antibiotic growth promoters in feed. The increasing consumer demand for meat results in more intensive meat production which implies that today more antibiotics are sold for animals than for humans, as is the case in the US. As a consequence, the improper application of antibiotics leads to residues in meat which enter the human organism and cause a higher risk of resistance towards antibiotics.

US health department

Last September the US health department confirmed the risk of supplemented antibiotics in regard to human health and as a consequence has recently banned a number of AGPs from livestock production. This is a crucial step to attain a sustainable livestock production which is a major driver economically, scientifically and legislatively. This action has the potential to generate a general rethinking in animal nutrition strategies and look for scientifically proven alternatives. Delacon started researching and  developing natural and sustainable solutions to replace AGPs with phytogenic feed additives more than 25 years ago. It resulted in the development and production of standardised feed additives comprising essential oils, herbs, and spices, with effects and benefits comparable to AGPs concerning nutrient efficiency, animal health and performance while guaranteeing safety in the food chain. Recently, the company held its first Advanced Swine Nutrition Conference for a professional audience in Vienna. Key accounts, European distributors and customers participated in an analytical exchange about swine nutrition and management as well as animal health with professionals and scientists from the economy and research institutions across Europe and the US. Promoting gut health for increased performance was one of the key topics within animal nutrition.

Quorum sensing

Dr Filip Boyen, Ghent University, introduced in his lecture ‘Quorum sensing in veterinary bacteriology’, the communication process amongst bacteria like Staphylococcus aureus and Salmonella typhimurium. He explained that this process is based on the sensing of certain molecules for communication purposes that are built and released by the bacteria themselves once they reached a certain population density within their host organism.

He said, “Thus, bacteria can act as ‘one organism’, which enables them to execute synchronised, pathogenic actions like biofilm formation and the production of antimicrobial substances against its host. The targeting of the quorum sensing mechanism provides a novel strategy for combating bacterial infections by disturbing their communication; thus increasing the susceptibility of the pathogen to the host’s defence mechanism. Plant substances may interfere with this quorum sensing, a process that is called ‘quorum quenching’.” He said, “Quorum quenching may have no direct effect on bacterial growth (in contrast to antibiotics) but rather interferes with the signalling of bacteria. Thus, it does not exert selective pressure towards the development of resistance and hence, could offer a significant alternative to AGPs.”

Antioxidant defense

One of the other speakers included Dr Andreas Mueller, Delacon R&D senior manager for poultry, presenting about antioxidant mechanisms in the metabolism for the maintenance and promotion of animal health. He touched on the link between damaging pro-oxidative processes and the potential of plant substances to counteract, such as essential oils, spices and herbs to act as direct antioxidants or activate antioxidative enzymes and thus, support health of high-performing farm animals. He said: “The antioxidant defence system of an organism basically assures protection against reactive oxygen compounds. In an organism, reactive oxygen species are derived from various sources. The highest amount of reactive oxygen species in an organism is generated during nutrient metabolism and during energy production in the respiratory chain. Thus rapidly growing farm animals like poultry, turkeys and piglets naturally have a high production of reactive  oxygen species, especially under warm temperature conditions, i.e. heat stress.

“Another important origin of reactive oxygen species may derive from the metabolism of environmental toxins like aflatoxin and other mold toxins. A further source of reactive oxygen species entering the organism comprises dietary factors like oxidised and just oxidising unsaturated fatty acids. The last important source for the generation of reactive oxygen species is the challenge of an organism with infections. Adequate antioxidant protection is necessary to prevent damage to the organism caused by oxidative stress.”


Phytogenic feed additives are an excellent source in the feed for bio-available antioxidants, Mueller explained. He said, “Various phytogenic compounds can exert both directly (by scavenging free radicals actively) and indirectly (by the excretion of enzymes) antioxidant effects. “Such a compound is ar-turmerone, contained in the essential oil of turmeric. Due to having an aromatic function ar-turmerone can scavenge and directly stabilise free radicals very well. On the other hand ar-turmerone has a keto group in its molecular structure which enables it to react with the sensitive sulphhydril group of Keap1 and to up-regulate endogenous antioxidant and phase II enzymes. “Moreover, various farm trials showed that all phytogenic feed additives increased the total antioxidant    capacity, measured using Trolox Equivalent Antioxidant Capacity, in the jejunum, representing the early small intestine, 2 to 4.5-fold. In addition, also Trolox Equivalent Antioxidant capacity in the liver, as an peripheral organ was strongly improved 2 to 3.5 fold. Phytogenic feed additives distinctly improve the total antioxidant capacity of an organism. The up-regulation of phytogenic additives in the intestine protects the organism against oxidative stress (intestinal barrier function).”

Concluding, Mueller said, “To find exact solutions to the increasing global population and consumer demand for high quality and safe food while saving the environment might not be as easy when looking for and evaluating alternatives to antibiotic growth promoters. Natural, standardised and proven scientifically and commercially phytogenic products offer vast potential for efficient animal production and safe food for the consumers.”

Source: Pig Progress magazine Vol 30 nr 1

Brötel Delacon