cover pic from PCM

Surfactants are an essential component of a wide variety of formulations across personal care, home care, cosmetics, and industrial applications. They are prevalent in the personal care products we choose and even the packaged goods we eat.

Surfactants are an essential component of a wide variety of formulations across personal care, home care, cosmetics, and industrial applications. They are prevalent in the personal care products we choose and even the packaged goods we eat.

For the last 20 years, the surfactant industry has championed sustainable efforts to curb greenhouse gas emissions by shifting the production of surfactants from petrochemicals to bio-based alternatives derived from plant-based feedstocks such as palm oil and manufacturing by chemical catalysis.

However, the rapid increase in demand for vegetable oils coupled with deforestation concerns have challenged the palm oil industry, and the presence of unwanted contaminants in ingredients creates risks for both suppliers and brands. These efforts to improve ingredient options have been good enough for a time, but the age of chemistry alone is looking to biology to offer better ingredient options. Biosurfactants are quickly taking centre-stage as a big innovative jump into the solutions needed for the future.

Feedstock and regulatory challenges, what is wrong with current surfactants?

Now, let us consider the surfactant landscape with two major trends, feedstock shifts and global regulatory concerns. Petrochemical based surfactants have been slowly moving away from fossil oil to source the hydrophobic carbon chains to renewable, naturally derived feedstocks, such as tropical tree oil (Figure 2), rapeseed oil (Figure 3), and even soybean oil.

Figure 4 demonstrates the spike in global production as a function of demand for these plant-based oils, which will continue expanding with global population growth and consumerism. Even more compelling is the vast efficiency difference shown in Figure 5 between palm kernel oil and all other vegetal-based oils, shown in the study conducted by the Food and Agriculture Organization of the United Nations in 2023.⁶

Read the full figure pics on PCM

Based on this data, one could conclude that shifting from palm oil to another oil source is not an efficient choice. The Roundtable on Sustainable Palm Oil (RSPO) works diligently to address deforestation, geopolitical, and social challenges with palm-based feedstock, creating positive progress. However, the recent experiences with supply chain challenges for regionally bound items during the pandemic have caused heightened awareness among brands and product companies as they seek more viable options with better global availability.

Furthermore, the recent destocking of personal care ingredients has exposed weaknesses in global supply chains, deepening the imperative for supply chain security and resilience across markets for raw materials and formulations. There seems to be no simple answer to surfactant’s dependency on oil feedstocks.

The second trend impacting surfactants is the regulatory concerns, like 1,4-dioxane contamination. 1,4-dioxane is an undesirable byproduct of the manufacturing process of ingredients such as sodium laurel ether sulfate (SLES), ethoxylated surfactants, some emollients, and ingredients produced by PEGylation.

According to the Center for Disease Control (CDC), 1,4-dioxane is listed in the Toxic Substance Portal with the statement, ‘The US Department of Health and Human Services (HHS) considers 1,4-dioxane as reasonably anticipated to be a human carcinogen. The EPA has established that 1,4-dioxane is likely to be carcinogenic to humans’.⁷

Furthermore, 1,4-dioxane contamination levels from specific raw materials in finished products may drift over time. The drift can come with a rate of change that is temperature and pH dependent, such that even if you assay a raw material for 1,4-dioxane, the level could drift over the shelf life of your finished product, driving uncertainty throughout the product’s lifecycle.

Raw material suppliers have worked to address this challenge with various manufacturing controls, but suppliers have limited ability to ensure the level of 1,4-dioxane presence in the final finished good by the time it reaches the consumer. Despite the debate on 1,4-dioxane, governments and regulatory bodies are driving discussions and/or restrictions on present levels in New York,⁸ California,⁹ Germany,¹⁰ Australia, and other regions.

What are the experts saying?

What is the answer to the 1,4-dioxane challenge? According to Kathleen Stanton, assistant vice-president of technical & international affairs at the American Cleaning Institute, and Douglas G. Hayes, institute professor of biosystems engineering and soil science at the University of Tennessee, one solution is to shift formulations to biosurfactants – specifically glycolipids – explaining they ‘possess excellent surface activity… highly biocompatible and biodegradable’.¹¹

Ruby Bio’s glycolipid approach

Biosurfactants can address the issues of 1,4-dioxane, but not all biosurfactants can remove the yoke our surfactant society has to oil, specifically palm oil. Charlie Silver and Pavan Kambam, co-founders of Ruby Bio, saw this as a landmark opportunity to bring positive change to personal care, home care and other industries.

These challenges warranted the development of a new class of biosurfactants produced via a nature-based fermentation process using abundant feedstock, such as sugar or sugar-waste, with no use of oil. Ruby Bio is pioneering a novel platform for biosurfactants that are also tunable.

Tunability enables the production of a wide range of surfactant variants and derivatives that closely resemble the core structure of legacy surfactants, with functionality that delivers equivalent or better performance. This new class of biosurfactants offers brands an opportunity to implement strategies for replacing petrochemical and other oil-based alternatives without compromising efficacy.

To make this opportunity a reality, Charlie and Pavan needed to identify a glycolipid-generating set of microorganisms with a high-performance profile. Pavan, having worked in industrial and food biotechnology leveraging precision fermentation, knew the parameters to make the biggest impact and pave the way for top performance.

The remarkable natural yeast used in Ruby’s platform is native to various regions across the globe but survives in hostile climates due to the high-performance glycolipid the yeast produces. This yeast uses internal metabolic pathways to convert simple sugars into the hydrophilic headgroup and a broad range of lipophilic tail groups, generating surfactant molecules up and down the HLB scale.

In nature, the yeast only has access to sugar as a feedstock, so the yeast naturally creates the molecules it needs to function using only sugar. The molecules constructed by the yeast vary by chain length, delivering different surfactant properties associated with the HLB values shown in Figure 1.

The yeast generates these molecules naturally to serve environmental functions of cleaning, emulsification, and even defence from pathogens. In harnessing nature’s own solutions to emulsification and cleaning challenges, we discover new biodegradable, environmentally friendly and gentle alternatives to historically oil-based synthetic ingredients.

Bio-fermented glycolipid from Ruby Bio; RubyGL-EM1™

Consider the emulsification properties of the glycolipid generated by the yeast at an HLB of 8- 9. This hydrophilic-lipophilic balance demonstrates strong oil-in-water emulsification as a primary emulsifier, or as a co-emulsifier in water-in-oil systems.

Unlike other glycolipids, the molecular structure is linear, and the material develops stable emulsions by forming small, uniform droplets dispersed in the continuous phase (Figure 6). These small uniform droplets enhance emulsion stability. The yeast evolved the glycolipid to naturally withstand severe shifts in temperature, which provides good thermostability as an ingredient.

Critical micelle concentration (CMC) is an important characteristic of a surfactant. The CMC specifies the limiting concentration for meaningful use in formulations in concert with other components. The CMC is the dose or level of surfactant at which the surfactant delivers optimum surface tension reduction, and surface tension cannot further reduce beyond this level.

Therefore, a surfactant with an extremely low CMC improves efficiency of the system. As demonstrated in Figure 7, the glycolipid bio-emulsifier can reduce the CMC of the primary surfactant at an impressively low dose, improving efficiency of the system and delivering top performance.

Since the yeast needs the glycolipid to perform various tasks beyond emulsification, we see great wetting and dispersing properties of our glycolipid. In nature, the yeast will experience minerals, dust, and various other external particles that the yeast has evolved the glycolipid to manage. This is useful for formulations.

Minerals such as titanium oxide, zinc oxide and pigments are used in cosmetic products and need proper dispersing and wetting to provide optimal performance. The challenge addressed by the yeast’s glycolipids in nature is the same as the challenge presented by minerals in formulations. Solid pigments added to the liquid medium will agglomerate, often entrapping air at the surface of the pigment agglomeration.

For proper wetting to occur, the air entrapped in the pigment needs wetting with a liquid medium. The use of a wetting agent, such as the glycolipid, speeds up the process and ensures complete wetting of the pigment and removal of the trapped air.

Ruby’s glycolipid provides excellent dispersing and wetting, with the same level of performance it has provided in nature for the yeast. These dispersing and wetting characteristics are key to excellent performance in formulations, as they are key to survival of the natural yeast. Ruby Bio is capturing the best performers in nature and harnessing these qualities into raw material ingredients.

Biology meets chemistry for an improved world

Another approach to this tunable platform is derivatization to create other functionalities. The yeast generates a simplistic base molecule with site-specific reactive groups, which provides opportunities for derivatization using chemistry to enhance and adjust properties of the original base molecule.

For example, simple attachment of the anionic group to the original molecule shows powerful fragrance solubility properties shown in Figure 8, while maintaining a 95% bio-based naturally fermented ingredient.

Other known glycolipids have not ventured towards such derivatization, potentially due to absence of unique desirable reactive groups but Ruby’s glycolipid base structure allows for a new class of surfactants and opportunities to arise from our simple fermentation. These derivatizations can provide bio-based, biodegradable solutions for personal care and other large volume industries such as oil & gas and home care.

Utilizing both nature and chemistry unlocks not only superior performance but also improved sustainability. Leveraging the initial molecule with various derivatizations creates multiple biosurfactant solutions from the same fermentation process while reducing cost, increasing demand, and driving economies of scale.

Ruby Bio at scale with sustainability in mind

Ruby Bio’s innovative fermentation platform harnesses highly efficient natural strains to produce novel glycolipids. We screened natural variants for robust glycolipid production to deliver optimal output naturally under specific conditions.

Focusing on natural efficiency unlocks commercially viable fermentation titers without needing to engineer the production strain. This allows the process to scale quickly and cost-effectively. The platform does employ genetic engineering efforts, but they are focused on pioneering new glycolipids, offering more solutions to our customers’ needs in the future.

Our initial glycolipid is a natural non-GMO yeast that produces a >95% pure glycolipid that is easily recovered from the fermentation. With manufacturing flexibility in mind, we intentionally developed our processes for efficient technology transfer and scale up.

Where possible, we simplified unit operations and opted for readily available equipment and well-proven manufacturing technologies. Robust but straightforward process conditions are employed and easily maintained, keeping product quality as our key focal point. This approach provides optionality and flexibility in manufacturing and reduces costs.

Our technology has easily transferred to manufacturing, with simple downstream processing, allowing us to manufacture in any geography as sugar feedstock is available everywhere. Our goal is to manufacture as close to our customers as possible, reducing our carbon footprint and improving overall sustainability. Fortunately, both sugar and sugar-waste are available anywhere, enabling global production.

In line with our commitment to sustainability, we have integrated the principles of Green Chemistry into our process design. For example, the feedstock for fermentation is renewable sugar. In fact, a wide range of sugars from various sources may be used, including sugar derived from waste streams.

Throughout the process we have kept energy consumption low by avoiding extreme processing conditions. We have also worked to find alternatives and limit the use of solvents in our derivatization processes for the functionalized ingredients.

After manufacturing, our spent biomass can easily be repurposed in other industries and our process has shown great ability to recycle and reuse water. These approaches not only align with our company’s values of offering environmentally responsible products, but they also contribute to cost control and supply chain security, enabling broad market potential.

Conclusion

Ruby Bio is focused on continuing our efforts to provide the world with high-performance bio-based, bio-derived surfactants, free from palm and toxic contaminants. We have launched two high-performing surfactants, with many more on the horizon.

The yeast naturally creates molecules up and down the HLB scale, so our job is to harness these molecules and offer them as useful building blocks for consumer products. We want to see the world shift to natural and nature-based ingredients, and our platform was designed to support this change.

In the face of elevated levels of geopolitical chatter, consumers need to know their choices are doing good and less harm. At the same time, consumers deserve the best performance, sustainably. Consumers are demanding transparency so they can understand when they are making good choices.

The desire for increased transparency and awareness of ingredient origins drives complexity only when an ingredient is complex. Bio-based and bio-derived ingredients offer consumers a simple understanding of a formulation’s composition and origins, reducing this complexity and improving consumer confidence. In our case, this origin is just sugar, and therefore transparency is easy to offer.

This simplicity of sustainability around biobased ingredients can help demystify the complexity that has been created for consumers around issues like 1,4-dioxane, feedstock origins, and calculating sustainability measures.

Leveraging a sugar-only feedstock has benefits beyond easy tracing. Ruby’s yeast variant is agnostic to sugar source, which unlocks a future for sugar-waste as a feedstock. This upcycling potential for waste-sugar drives our surfactants – the building blocks of any formulation – toward a circular economy and the next generation of bio-surfactants.