New Wave of Biosolutions Series

1. Metabolites in Crop Protection

Metabolites can originate from both chemical and biological processes, each playing a crucial role in crop protection and plant growth.

Chemical metabolites are the products formed when compounds, such as synthetic pesticides, undergo chemical reactions or degradation in the environment. These metabolites can sometimes be more active or effective than the parent compound, playing a critical role in the overall efficacy of crop protection chemicals.

Example: Metsulfuron-methyl

• Metsulfuron-methyl is a sulfonylurea herbicide used to control broadleaf weeds in cereals and pastures. After its application, it undergoes chemical transformation in the environment, leading to the formation of methylsulfonylurea, a metabolite that is primarily responsible for its herbicidal activity. This metabolite inhibits the acetolactate synthase (ALS) enzyme, which is essential for the synthesis of branched-chain amino acids in plants.

Biological Metabolites are produced naturally by living organisms and are classified into:

1. Primary Metabolites: Essential for the basic survival functions of the organism, such as energy production and growth.
2. Secondary Metabolites: Not essential for basic survival but provide the organism with additional advantages, such as defense against pests or pathogens.

Biological metabolite products with a complex composition, such as those derived from the fermentation of bacteria, consist of a wide array of compounds, including amino acids, carbohydrates, vitamins, and secondary metabolites. This complexity makes it challenging to pinpoint their exact mode of action. The diverse and heterogeneous nature of these products requires advanced and specialized analytical techniques to fully understand their effects, which can be time-consuming and resource-intensive.

In contrast, products with a specific composition containing only one or two metabolites offer a clearer and more straightforward approach. With fewer components, the mode of action can be more easily investigated and demonstrated. This simplicity allows for more precise studies, making it easier to understand how these specific metabolites interact with pests or plants, and how they contribute to crop protection or biostimulation. As a result, these products can be developed, validated, and brought to market more efficiently, with clear, scientifically backed explanations of how they work.

Examples of Biological Metabolites in Crop Protection

Spinosyn A and Spinosyn D

Spinosyn A + Spinosyn D are a prime example of the potential of biological metabolites as powerful crop protection products. Derived from the soil bacterium Saccharopolyspora spinosa, this metabolites are the active ingredients in Spinosad one of the best-selling insecticides, competing head-to-head with top synthetic counterparts. Its effectiveness in controlling a wide range of pests, combined with its low toxicity to non-target species, makes it a standout reference of how biological solutions could rival, and even surpass, synthetic options in the marketplace.

Despite its biological origins, Spinosad is not classified as a biological product due to the chemical modifications and processes involved in its production. These modifications, designed to enhance its efficacy and stability, mean it falls under the category of synthetic chemicals from a regulatory perspective, even though the metabolites are produced by a natural organism.

Metabolite-Based Biosolutions Classified as Biologicals

The success of Spinosad demonstrates the immense potential of biological metabolites in crop protection. The challenge lies in harnessing this potential in a way that allows these products to be classified as biologicals, which requires producing metabolites without extensive chemical modifications. To achieve this, the production process must align with regulatory requirements for biological crop protection or biostimulant products. One of the primary hurdles is the complexity of isolating and purifying specific metabolites from a natural fermentation mixture.

To overcome the challenges associated with using chemical stabilizers and solvent-based extraction methods, alternative approaches can be employed, such as utilizing organic substances to prevent degradation and stabilize the active ingredients. For instance, natural antioxidants or biopolymers can serve as stabilizers, protecting the metabolites from degradation without introducing synthetic chemicals. Similarly, organic solvents derived from natural sources, like ethanol or plant-based oils, can be used in the extraction process, ensuring the product remains within the boundaries of organic classification.

Furthermore, optimizing microbial fermentation conditions, using selective media to encourage the production of target metabolites, and applying advanced extraction methods such as molecularly imprinted polymers, solid-phase microextraction, countercurrent chromatography, membrane filtration, and pressurized liquid extraction can enhance the overall process. Additionally, integrating continuous bioprocessing and real-time monitoring using biosensors can help maintain product consistency and purity, making the process more efficient and viable for large-scale production. These approaches would enhance the feasibility of developing metabolite-based biosolutions that meet the stringent criteria for biological classification, ultimately expanding their use in sustainable and organic farming practices.

Benefits of Metabolite-Based Biosolutions Without Live Cells

1. Stability and Shelf Life: Metabolite-based products generally have much greater stability compared to those containing live organisms. Without the need to keep organisms viable, these products can maintain their effectiveness over a longer period. Longer shelf life reduces the frequency of product replacement and waste, leading to cost savings for both manufacturers and farmers. It also ensures that the product remains potent until it is used, providing consistent performance in the field.
2. Intellectual Property Protection: Metabolite-based products offer enhanced protection for intellectual property (IP). Since metabolites can be precisely characterized and synthesized, they can be patented with greater clarity compared to live organisms, which might evolve or change. Stronger IP protection encourages innovation by giving companies confidence that their investments in research and development will be safeguarded. It also reduces the risk of biopiracy, where biological resources are exploited without proper authorization or benefit-sharing.
3. Quicker Efficacy: Metabolite-based products often exhibit quicker efficacy compared to live biologicals. Since metabolites are the active substances responsible for pest control or plant growth promotion, they begin working immediately upon application, without the need for the establishment, growth, or activation of live organisms. Faster action means pests are controlled more quickly, reducing damage to crops and improving yield. This immediacy can be critical during peak pest outbreaks when timely intervention is essential to protect crops.
4. Consistency in Efficacy: Metabolites deliver consistent results because their activity is not influenced by environmental conditions that might affect live organisms, such as temperature, pH, or moisture levels. Farmers can rely on a predictable level of efficacy, which improves crop management and reduces the risk of crop loss due to inconsistent product performance.
5. Compatibility with Agrochemicals: Metabolite-based biosolutions are generally more compatible with other agrochemicals, such as synthetic pesticides and fertilizers, since they do not contain live organisms that could be harmed by these chemicals. This compatibility allows for integrated pest management strategies, combining the benefits of biological and chemical control methods without reducing the efficacy of either.
6. No Special Handling Required: Metabolite-based products do not require special handling, such as refrigeration or protection from environmental stressors, since they do not contain live cells. Easier storage and application make these products more accessible to farmers, particularly in regions with challenging conditions or limited infrastructure.
7. Reduced Environmental Impact: Metabolites typically degrade naturally in the environment, reducing the risk of long-term accumulation or harm to non-target organisms. This contributes to a lower environmental footprint, aligning with the goals of sustainable agriculture and minimizing potential negative effects on ecosystems.
8. Flexibility in Formulation: Metabolite-based products can be formulated in various forms, such as liquids, granules, or sprays, without worrying about keeping organisms alive. This flexibility allows for tailored application methods suited to different crops, climates, and farming practices.

By leveraging natural production methods, we can create effective, sustainable, and environmentally friendly solutions that meet the regulatory standards for biological products. As these next-generation biosolutions become more widely available, they are set to play a crucial role in sustainable agriculture, offering farmers effective tools to protect and nurture their crops while minimizing environmental impact. Looking ahead, as consumer demand for organic and eco-friendly food continues to rise and the prices of organically produced crops become more competitive with conventional options, organic and eco-farming practices are poised to take on a more prominent role in global agriculture. This shift will not only drive innovation in crop protection but also contribute to a healthier, more sustainable food system that meets the evolving preferences of consumers worldwide.