Trehalose in Biofertilisers & Microbial Inoculants
One of the most commercially important agricultural uses of trehalose has little to do with applying it directly to plants.
Instead, trehalose can be used to help protect the beneficial microorganisms contained within modern biological agricultural products.
Biofertilisers and microbial inoculants increasingly use living bacteria and fungi to support processes such as nitrogen fixation, nutrient availability, root development and plant establishment. But these organisms face a fundamental problem:
They have to survive manufacture, drying, storage, transportation and application before they can benefit the crop.
Trehalose is particularly well suited to this challenge because of its ability to help protect cells, membranes and proteins against desiccation, osmotic stress and other environmental pressures.[1,2]
Research spanning more than two decades has demonstrated these protective effects in agriculturally important microorganisms including Bradyrhizobium, Rhizobium and, more recently, Azospirillum brasilense.[1–5]
Nagase now supplies dedicated TREHALOSE Agricultural Grade for applications including microbial inoculants, seed coatings and biological agricultural formulations.[6]
What are biofertilisers and microbial inoculants?
Microbial agricultural products contain beneficial living organisms intended to interact with plants, roots or soils.
Depending on the organism and product, they may help with:
- biological nitrogen fixation
- nutrient mobilisation
- root colonisation
- plant-growth promotion
- establishment of beneficial microbial communities
- improved nutrient-use efficiency.
Some of the best-known examples are rhizobia, the nitrogen-fixing bacteria that form nodules on the roots of legumes.
Other important agricultural microorganisms include:
- Azospirillum
- Bacillus
- Pseudomonas
- arbuscular mycorrhizal fungi
- other plant-growth-promoting rhizobacteria.
These biological inputs can offer valuable agricultural functions, but they are fundamentally different from conventional chemical fertilisers.
The active component is alive.
If too many microbial cells die before the product reaches the field, the formulation may no longer perform as intended.
The formulation problem: keeping microorganisms alive
Microbial inoculants can encounter severe stresses during manufacture and use.
These include:
- drying
- freeze-drying
- spray-drying
- changes in osmotic pressure
- high or fluctuating temperature
- prolonged storage
- low humidity
- exposure on seed surfaces
- rehydration after storage.
Seed-applied microorganisms face an especially demanding environment.
Bacteria may have to survive the drying stage during seed coating, remain viable throughout storage and then tolerate environmental conditions after planting.
Research into Rhizobium leguminosarum describes desiccation as one of the major causes of microbial losses during seed-coating and storage processes.[2]
This creates a significant formulation challenge:
How can a biological agricultural product keep enough microorganisms alive for long enough to remain useful?
Trehalose offers one potential solution.
Why does trehalose protect microorganisms?
Trehalose is a naturally occurring non-reducing disaccharide found in many microorganisms and other organisms exposed to environmental stress.
Many bacteria naturally produce or accumulate trehalose when conditions become difficult.
It acts as a compatible solute, helping organisms respond to changes in osmotic pressure without disrupting normal cellular processes.
Trehalose can also help stabilise:
- cell membranes
- proteins
- enzymes
- other biological structures
during dehydration.[2]
One important explanation involves its interaction with water.
As cells dry, water molecules that normally help maintain membrane and protein structure disappear. Trehalose can interact with these biological structures and help preserve their organisation during dehydration.
Under sufficiently dry conditions, trehalose can also contribute to formation of a highly viscous or glass-like matrix, reducing molecular movement and helping stabilise sensitive biological material.
These properties explain why trehalose is used far beyond agriculture in applications involving the protection of cells, proteins and other biological systems.
For microbial agricultural formulations, the same properties can be highly valuable.
Evidence from Bradyrhizobium japonicum
One of the clearest early demonstrations came from research into Bradyrhizobium japonicum, an agriculturally important soybean-associated bacterium.
A 2003 study specifically investigated whether trehalose could improve bacterial survival during desiccation.[1]
The researchers supplied trehalose either immediately before drying or during bacterial growth.
Adding trehalose immediately before desiccation produced only a modest improvement.
Much stronger protection occurred when the bacteria were grown in the presence of trehalose, allowing the cells themselves to accumulate more of it.[1]
Growth with 3 mM trehalose increased intracellular trehalose by approximately threefold.
When these cells were subsequently placed on soybean seeds, survival after drying was around two to four times greater than in untreated bacteria after the periods examined.[1]
Across the experiments, growing the bacteria with trehalose produced an average 294% increase in survival after 24 hours of desiccation.[1]
The concentration of trehalose within the cells was also strongly associated with bacterial survival.
This provided an important early demonstration that trehalose metabolism and accumulation could materially influence the ability of an agricultural microorganism to survive dehydration.
Trehalose is part of the microorganisms' own stress defence
Research in Rhizobium leguminosarum subsequently strengthened this conclusion.
Scientists investigated bacterial strains able to manufacture trehalose naturally and compared them with mutants in which important trehalose-biosynthesis pathways had been disrupted.[2]
The bacteria unable to accumulate trehalose were significantly more vulnerable to drying.
They also performed less successfully when competing to occupy root nodules.[2]
When bacterial cells were experimentally dried in trehalose solution, survival was also greater than under several comparator conditions used in the study.[2]
Together, these findings demonstrate something important:
Trehalose is not simply an arbitrary additive chosen by formulators. It is already part of the natural stress-protection system used by many agricultural microorganisms.
Reviews of rhizobial and plant-microbial relationships have subsequently identified trehalose as an important compatible solute associated with survival under desiccation, osmotic and temperature stress.[3]
Why this matters for nitrogen-fixing inoculants
Rhizobial inoculants are particularly important in legume agriculture.
These bacteria form specialised structures called nodules on plant roots.
Inside the nodules, they convert atmospheric nitrogen into forms that the plant can use.
This biological nitrogen fixation can substantially reduce the crop's dependence on externally supplied nitrogen.
But successful inoculation requires the bacteria to survive long enough to:
- reach the soil,
- colonise the developing root,
- interact with the plant,
- establish functional nodules.
Microbial death during formulation, seed coating or storage can therefore reduce the opportunity for successful nodulation.
Trehalose's ability to protect rhizobia during dehydration has obvious relevance to the development of more stable inoculant products.[1–3]
Nagase Viita has also identified rhizobial formulation as an established commercial agricultural application for trehalose, particularly in South American soybean production.[7]
Trehalose in biological seed coatings
One particularly interesting development combines microbial inoculation with modern seed-coating technology.
Researchers reported a sophisticated two-layer seed coating in Nature Food in 2021.[4]
The system contained:
an inner silk-and-trehalose layer containing beneficial rhizobacteria
and
an outer pectin/carboxymethylcellulose layer designed to absorb water after sowing.
The outer layer effectively acted as a small water-retaining environment around the germinating seed, while the inner layer delivered the microorganisms.
The technology was tested using common bean in semi-arid conditions in Morocco.
The coated seeds successfully delivered rhizobacteria to the roots, promoted nodule formation and produced healthier plants under water-stress conditions.[4]
Trehalose was only one component of a deliberately engineered multi-material system, so the complete agricultural response cannot be attributed to trehalose alone.
However, the research demonstrates a particularly important future application:
Trehalose can form part of engineered seed coatings designed to preserve and deliver living beneficial microorganisms.
That creates an opportunity quite different from conventional foliar biostimulants.
Dry biofertilisers and Azospirillum
A significant development was published in 2026.
Researchers at Embrapa and collaborating institutions developed a dry biofertiliser containing Azospirillum brasilense.[5]
Azospirillum is one of the most important groups of plant-growth-promoting bacteria used in agriculture.
Conventional liquid inoculants can have limitations because the bacteria remain vulnerable to environmental and storage stresses.
The researchers therefore encapsulated A. brasilense within a matrix made from poly(glycerol citrate) and trehalose.[5]
They then compared three drying techniques:
- convection drying
- freeze-drying
- spray-drying.
All three produced initial bacterial viability of approximately:
10⁸ colony-forming units per gram
under the conditions investigated.[5]
Most importantly, the freeze-dried formulation maintained approximately this level of viability for more than 180 days.[5]
When applied to maize seed, the freeze-dried formulation also produced significantly greater bacterial recovery than the conventional liquid inoculant used for comparison.[5]
This is highly relevant commercially.
It demonstrates the feasibility of using trehalose as part of a formulation designed to turn a sensitive living bacterial product into a dry, storable agricultural inoculant.
Again, the protective system contained both the polymer and trehalose, so the result represents the performance of the complete formulation rather than trehalose alone.
Nevertheless, trehalose was deliberately incorporated as an osmoprotectant to help protect the bacterial cells during drying.[5]
Why dry microbial formulations are attractive
Dry biological agricultural products potentially offer several advantages over conventional liquid inoculants.
Depending on the organism and formulation, these can include:
- improved storage stability
- easier transportation
- reduced contamination risk
- compatibility with seed treatment
- potentially longer shelf life
- easier handling
- reduced dependence on tightly controlled storage conditions.
The major obstacle is that drying itself can kill microorganisms.
This is precisely where trehalose becomes interesting.
Rather than merely serving as an inert carrier, trehalose can contribute directly to protecting biological structures while water is removed.
This creates potential applications in:
- freeze-dried inoculants
- spray-dried microbial formulations
- powdered biofertilisers
- biological seed coatings
- dry microbial concentrates.
The appropriate formulation nevertheless depends heavily on the microorganism being protected and the drying process being used.
Trehalose and microbial seed survival
The seed surface presents another important challenge.
Once an inoculant is applied, bacteria may encounter:
- rapid dehydration
- temperature fluctuations
- long periods before germination
- interactions with seed-treatment chemicals
- changing humidity
- limited nutrient availability.
Research in rhizobia demonstrates that desiccation losses can occur very quickly after microorganisms are applied to seeds.[1,2]
The 2003 Bradyrhizobium experiments showed that bacteria containing higher concentrations of trehalose survived substantially better after placement on soybean seeds.[1]
The later Nature Food and Azospirillum studies demonstrate two different technological approaches to the same problem:
protect the microorganism during storage and delivery so that viable cells remain available when the seed germinates.[4,5]
This makes microbial seed treatments one of the strongest areas for future trehalose formulation development.
Trehalose and microbial stress tolerance
The protective role of trehalose is not limited to drying.
Agricultural microorganisms can also experience:
- osmotic stress
- salinity
- heat
- cold
- oxidative stress.
Trehalose is widely involved in microbial responses to these environmental pressures.[2,3]
Rhizobia naturally accumulate trehalose during stressful conditions, and research into trehalose biosynthesis has demonstrated links between cellular trehalose concentration and survival.[1–3]
That suggests two related formulation strategies.
External protection
Trehalose is added directly to a formulation where it helps protect microbial structures during drying and storage.
Cellular trehalose accumulation
Culture conditions are designed so that microorganisms accumulate more trehalose within their own cells before processing.
The Bradyrhizobium study is particularly interesting because the second strategy proved more effective than simply adding trehalose immediately before drying.[1]
This raises opportunities not only for trehalose as a finished-product ingredient, but also as part of the microbial production and fermentation process.
Rhizobia, mycorrhizae and plant–microbe interactions
Trehalose also has biological roles within the interactions between microorganisms and plants.
Research reviews have examined trehalose metabolism in relationships involving:
- legumes
- rhizobia
- arbuscular mycorrhizal fungi.[3]
Rhizobia can accumulate considerable quantities of trehalose, particularly during stressful conditions and during parts of their symbiotic relationship with plants.
Trehalose is therefore involved not only in preserving microbial cells outside the plant but also in microbial stress physiology associated with plant colonisation and nodulation.[2,3]
The research involving arbuscular mycorrhizal fungi is scientifically interesting but less mature from a formulation perspective.
At present, the strongest commercial evidence remains with bacterial inoculants, particularly rhizobia and plant-growth-promoting bacteria.
Does trehalose increase microbial inoculant shelf life?
The evidence strongly supports the underlying principle that trehalose can improve microbial stability, but there is no universal shelf-life figure.
Shelf life depends on:
- microbial species and strain
- formulation chemistry
- trehalose concentration
- carrier material
- drying method
- residual moisture
- storage temperature
- packaging
- oxygen exposure
- relative humidity.
The 2026 Azospirillum formulation maintained approximately 10⁸ CFU/g for more than 180 days, but that result applies specifically to the polymer-trehalose formulation and storage conditions tested.[5]
Nagase also commercially positions agricultural trehalose for improving the stability and shelf life of microbial inoculants.[6]
Any commercial inoculant therefore needs its own shelf-life and viability validation rather than relying on a figure derived from another organism or formulation.
Trehalose in bio-control formulations
Trehalose's stabilising properties may also be useful where the biological active ingredient is a microorganism used in a biological-control formulation.
Nagase identifies bio-control formulations among the applications for its agricultural-grade trehalose.[6]
The underlying formulation challenge is similar:
a living organism must retain sufficient viability and functionality during manufacturing and storage.
However, microbial plant-protection products can fall within specific regulatory regimes depending on the organism, intended use and claims.
Trehalose should therefore be regarded as a formulation stabiliser, not as evidence that the finished product itself has regulatory approval or proven pest-control efficacy.
Formulation matters
Trehalose is not a magic preservative that will stabilise every organism under every condition.
Successful microbial formulation requires optimisation of the entire system.
Important variables include:
Microorganism
Different bacteria and fungi vary substantially in their tolerance to dehydration, heat and osmotic stress.
Trehalose concentration
The optimum amount depends on the organism and formulation process.
Carrier system
Trehalose may be combined with polymers, proteins, polysaccharides or other protective ingredients.
Drying method
Freeze-drying, spray-drying and conventional drying expose microorganisms to very different stresses.
Residual moisture
Too much remaining water can reduce storage stability, while excessive drying may damage sensitive cells.
Storage conditions
Temperature, humidity and oxygen exposure can materially affect long-term survival.
Rehydration
A microorganism must survive not only drying but also the transition back into an active hydrated state.
For these reasons, agricultural trehalose should be regarded as a functional formulation ingredient requiring system-specific validation.
Liquid inoculants
Trehalose can also have applications in liquid biological formulations.
Even without a complete drying step, microorganisms may experience osmotic and temperature stresses during production and storage.
Nagase currently positions agricultural-grade trehalose for liquid inoculant stabilisation as well as dry and seed-coating applications.[6]
The exact role will depend on the organism and formulation, but potential objectives include:
- maintaining microbial viability
- reducing stress during storage
- stabilising cell membranes and proteins
- helping formulations tolerate changing environmental conditions.
This broadens the potential market beyond dry biofertilisers alone.
A potentially important B2B agricultural application
From a commercial perspective, microbial formulation is particularly interesting because it represents an ingredient-to-manufacturer market.
The customer is not necessarily a farmer applying pure trehalose directly to a crop.
Instead, the potential customer may be:
- a biofertiliser manufacturer
- an inoculant producer
- a seed-treatment company
- an agricultural biotechnology company
- a fermentation business
- a microbial formulation laboratory
- a biological-control manufacturer
- a university or agricultural research organisation.
The trehalose then becomes one component within a more sophisticated finished agricultural product.
This is particularly attractive because the value proposition is based on one of trehalose's most established technical characteristics:
the stabilisation and protection of biological materials during environmental stress.
Agricultural-grade trehalose
Nagase Viita manufactures a dedicated TREHALOSE Agricultural Grade.
The company identifies agricultural applications including:
- biofertilisers
- microbial inoculants
- seed coatings
- biological formulations
- plant-biostimulant development.[6]
Nagase has also described commercial use of trehalose in rhizobial formulations for soybean production in South America, where it has been used to improve microbial stability.[7]
In 2026, Nagase Viita further described trehalose as an indirect biostimulant stabiliser within its international agricultural-development programme, alongside its direct use on crops.[8]
This confirms that microbial formulation is not merely an academic application of trehalose: it is already part of Nagase's agricultural commercial strategy.
TREHALOSE Agricultural Grade and TREHA® are not the same product
This distinction is important for commercial users.
Nagase Viita manufactures different trehalose grades for different markets and technical requirements.
TREHA® is its established food-grade trehalose.
For specialist agricultural formulation, Nagase produces TREHALOSE Agricultural Grade.[6]
Although both products contain trehalose, agricultural manufacturers should select a product grade with the specifications, documentation and supply arrangements appropriate to their intended application.
Trehalose UK should therefore not assume that existing food-grade TREHA® is automatically interchangeable with Nagase's dedicated agricultural product.
From living microorganism to stable agricultural product
The potential of microbial agriculture depends on more than discovering useful organisms.
Those organisms must also be converted into products that can be:
- manufactured reliably
- stored
- transported
- applied
- and remain biologically active when they reach the crop.
That formulation challenge is increasingly important as agriculture moves towards more sophisticated biological inputs.
The research surrounding trehalose provides a strong underlying proposition:
Trehalose can help beneficial agricultural microorganisms survive dehydration and other formulation stresses, creating opportunities for more stable biofertilisers, inoculants and biological seed treatments.
The evidence now spans early rhizobial desiccation studies, microbial physiology, engineered seed coatings and modern dry biofertiliser formulations.[1–5]
For agricultural biotechnology companies, this potentially makes trehalose much more than a plant biostimulant.
It is also a biological formulation ingredient.
Trehalose for microbial agricultural formulations
Trehalose UK is developing its support for agricultural and biological-formulation applications of genuine Japanese trehalose.
We welcome enquiries from:
- biofertiliser manufacturers
- microbial inoculant producers
- seed-treatment businesses
- agricultural biotechnology companies
- formulation laboratories
- fermentation businesses
- research organisations.
For product-grade requirements, development quantities, technical enquiries or commercial supply, contact:
For a broader overview of agricultural applications, read:
Trehalose in Agriculture: Uses, Benefits & Research
References & further reading
[1] John G. Streeter. 2003. “Effect of Trehalose on Survival of Bradyrhizobium japonicum during Desiccation.” Journal of Applied Microbiology 95, no. 3: 484–491. DOI: 10.1046/j.1365-2672.2003.02017.x. Demonstrates the relationship between intracellular trehalose and survival of B. japonicum during drying and on soybean seed. EnviroMicroJournals
Read the study
[2] Helen J. McIntyre, Holiday Davies, Timothy A. Hore, Simon H. Miller, Jean-Pierre Dufour, and Clive W. Ronson. 2007. “Trehalose Biosynthesis in Rhizobium leguminosarum bv. trifolii and Its Role in Desiccation Tolerance.” Applied and Environmental Microbiology 73. DOI: 10.1128/AEM.00412-07. Demonstrates the importance of trehalose biosynthesis for rhizobial survival during drying and nodulation-related stress. ASM Journals
Read the study
[3] Meghna P. Sharma et al. 2020. “Deciphering the Role of Trehalose in Tripartite Symbiosis Among Rhizobia, Arbuscular Mycorrhizal Fungi, and Legumes for Enhancing Abiotic Stress Tolerance in Crop Plants.” Frontiers in Microbiology 11: 509919. DOI: 10.3389/fmicb.2020.509919. Review of trehalose in rhizobial, mycorrhizal and legume stress biology. Frontiers
Read the review
[4] Augustine T. Zvinavashe, Julie Laurent, Benedetto Marelli, et al. 2021. “Programmable Design of Seed Coating Function Induces Water-Stress Tolerance in Semi-Arid Regions.” Nature Food 2: 485–493. DOI: 10.1038/s43016-021-00315-8. Describes a silk/trehalose microbial seed-coating system tested with common bean in semi-arid Morocco. Nature
Read the study
[5] Bruna Lendzion Alves, Lucas S. Ribeiro, Mariangela Hungria, and Caue Ribeiro. 2026. “Dry Biofertilizer Development Containing Azospirillum brasilense: A Protective PGCit-Based Strategy for Seed Inoculation.” ACS Agricultural Science & Technology 6, no. 2: 322–331. DOI: 10.1021/acsagscitech.5c00714. Reports a polymer–trehalose dry biofertiliser formulation retaining approximately 10⁸ CFU/g for more than 180 days following freeze-drying. ACS Publications
Read the study
[6] NAGASE Europe. “Trehalose for Agriculture.” Current technical and commercial information on agricultural-grade trehalose for microbial inoculants, seed coatings, biological-control formulations and plant biostimulants. NAGASE | Europe
NAGASE agricultural information
[7] Nagase Viita Co., Ltd. “Pioneering the Way to Making Sustainable Agriculture a Reality: Biostimulants Offering New Solutions.” Describes the company's development and commercial use of trehalose in rhizobial preparations for soybean production in South America. Nagase Group
Read the Nagase article
[8] Nagase Viita Co., Ltd. 2026. “Trehalose-Based Agricultural Support Project Selected for JICA Biz Program (FY2025).” Describes trehalose both as a direct crop biostimulant and as an indirect stabilising ingredient for biological agricultural formulations. Nagase Group
Read the Nagase announcement