Bioactive-based solutions in biotechnology, agriculture and environmental management

Objective: Explore natural product applications in industry.

Key questions: What are biotechnologies? How can natural products help us towards One Health?

Natural products have extensive applications in biotechnology, agriculture, aquaculture and environmental management. We will now look at some examples from these sectors.

Biotechnology – harnessing the power of biological systems

Biotechnology can be defined as the controlled and deliberate manipulation of biological systems (whether living cells or cell components) for the efficient manufacture or processing of useful products. It is possible to obtain a wide variety of substances that are useful to us as food, fuel and medicine. Biotechnology can also carry out specific processes that we need.

Biotechnology has applications in many industries. In the food industry, yeast and bacterial strains perform the fermentation processes needed to produce products like wine, cheese, breads and beer. Biotechnology has allowed huge advances in the manufacture of pharmaceuticals. With advances in genetic engineering, cells can be programmed to produce complex molecules.

One such molecule is insulin, used for the treatment of diabetes. In 1978, the bacteria Escherichia coli was engineered to produce synthetic ‘human’ insulin. Until then, insulin was extracted for use in medicine from the pancreas of pigs but with this advancement, large quantities could be synthesised cost-effectively in bacteria or yeast. Plant cells have also been successfully engineered to produce human insulin.

Biotechnology also harnesses the power of enzymes. Enzymes are proteins that can speed up or facilitate chemical reactions. They are biological catalysts. In living organisms, our metabolic pathways are dependent on enzymes performing functions to convert starting molecules into new molecules, the products. Enzymes are involved in all our physiological processes.

One example is the digestion of proteins into smaller components in the stomach by the enzyme pepsin. Enzymes also have applications outside living cells. Fermentation is one such process. For example, in alcohol production yeast enzymes convert sugars to ethanol and carbon dioxide. Fermentation is also of huge interest as process for production of renewable and sustainable fuels like bioethanol.

For some processes, enzymes can be used without whole cells, removing the need to provide nutrients or maintain cell growth in culture. We are familiar with biological washing powders that use enzymes to fight stains, breaking down the residues of food and stains such as grass.

In environmental biotechnology, enzymes can be utilised to aid decomposition of wastes. Enzymes can be used to degrade or reduce harmful or undesirable environmental pollutants to clean contaminated sites (enzyme mediated bioremediation). Enzymes can give highly specific actions, are biodegradable and nontoxic and so can be an ecofriendly alternative to chemical catalysts.

Natural products in livestock management

Natural products have applications as feed additives in the management of livestock increasing nutritional value to enhance growth. Natural products may also have applications in veterinary medicine and animal welfare and health.

Reducing antimicrobial use in livestock management with natural products

Antimicrobial resistance is one of the top 10 threats to global health according to the World Health Organisation. The development of antibiotics in the last century has allowed us to cure infections caused by bacteria that would otherwise result in significant morbidity and mortality.

However, the overuse of drugs can lead to drug resistance, and this can result in treatment failure. It is imperative that we use our armoury of antibiotics prudently to reduce the development of antimicrobial resistance. It is estimated that around 80% of total global antimicrobial use occurs in livestock and so this antimicrobial use is a focus of concern.

Public health is no longer considered to refer to just human health and there is increasing awareness of the interdependence of human and animal health and ecological change. One Health is an integrated, unifying approach to balance and optimize the health of people, animals and the environment.

The need for antimicrobials in livestock management is largely determined by husbandry practices. For example, in pig production, weaning of piglets frequently leads to intestinal disorders and diarrhoea due to change in diet, physical and social environment. This often requires antibiotic treatment. Feed additives and supplements in combination with improved animal husbandry practices, can reduce or completely remove the need for antibiotics.

Probiotics or live ‘good’ bacteria can support the microbiome for improved gut health. Inclusion of prebiotics such as dietary fibres in-feed can support growth of ‘good’ bacteria in the gut. Plant extracts such as tea tree oil, Chinese skullcap and fragrant agrimony have also been examined as alternatives to antibiotics in pig production.

In Europe, zinc oxide supplementation became a popular alternative following the ban of in-feed antibiotics in livestock in 2006. However, concerns remain about unintended environmental pollution consequences of zinc oxide usage as well as the promotion of antimicrobial resistance.

The research project “NATURPORKS”, carried out by the University of Murcia, the Murcia Institute for Agricultural Development and Food Research (IMIDA), and Dalland Hybrid Espana (DHESA) in Spain, focused on studying purple garlic powder and oregano essential oil as feed additives in 1,500 pigs under normal production conditions with the objective of replacing compounds like zinc oxide and to reduce the use of antibiotics.

Projects such as NATURPORKS provide us with the knowledge we need to produce high-quality pork with minimal antibiotic use in a sustainable way. Feed additive solutions must be considered alongside other ways to reduce reliance on antimicrobials that are under investigation.

Vaccination is an option for protection against specific pathogens. Other measures include adoption of good farming practices in biosecurity and hygiene but more study is needed to determine the impact of changes in production on disease and resultant antimicrobial usage.

Reducing agricultural methane emissions with seaweed

Teagasc, the Agriculture and Food Development Authority in Ireland, is investigating the effects of seaweeds and seaweed-ingredients on methane emissions from pasture-based sheep, cattle and dairy cows in its project “Seasolutions”.

Methane is the second most important greenhouse gas (GHG) contributor to climate change following carbon dioxide. 60% of global methane emissions result from human activity in the energy, agriculture and waste sectors and reducing methane emissions associated with human activity by 50% over the next 30 years would mitigate against global temperature change by 0.2°C, a significant step towards keeping the overall temperature increase below 2°C. Methane associated with livestock production account for 68% of Irish agricultural GHG emissions and almost 19% of our national GHG emissions.

Livestock such as cattle and sheep can derive nutrition from plant material such as grass. The microbes in their digestive system help them do this and methane is a natural by-product of this process.

The Seasolutions project team has achieved methane reductions of between 11% and 20% in early trials with native Irish brown seaweeds which could be a sustainable source for the livestock sector and contribute significantly to reducing emissions from the sector. In addition to the feeding of methane-reducing supplements, strategies to reduce agricultural methane emissions such as animal breeding and performance improvement measures such as optimisation of age at slaughter are under research.