Natural Preservative Systems: Is Leucidal Antifungal?

diy ingredients
Spread the love

A question from a reader prompts my reply about Leucidal and using essential oils for preservation in natural cosmetics, particularly creams and lotions (water-based products). I think many people want this information so I turned it into a post! Enjoy and please leave comments or share!

Reader question:

Hi Michelle,

I’m interested in your use of Leucidal and your reference to Synergy antioxidant blend.

I have been studying herbalism for years, and have a small business in which I make a line of body products as well as various herbal edibles. I currently use a synthetic preservative in the three lotions I make because I want to offer shelf stability. I’d love to get away from the preservative and have been watching Leucidal. So far I haven’t made the change because it doesn’t address fungal spread in a cream. I’m wondering how you address that.

And simply haven’t heard of Synergy. I Googled it and got nowhere, and I checked at Mountain Rose. Can you tell me the full name so I can look into it?

It really bugs me that I have this chemical in my line. But short of telling people to use the product within a couple of months or to keep it in the frig, I don’t see options. I’d love to hear what you’ve come up with!

Thanks. I’ll be watching the site!


My answer:

Hi M,

I’m glad we got in touch.

Leucidal is a broad spectrum antifungal and antibacterial. It has been shown effective for the following microorganisms:

Staphylococcus aureus: gram positive bacterium
Escherichia coli: gram negative bacterium
Pseudomonas aeruginosa: gram negative
Klebsiella pneumoniae: gram negative
Burkholderia cepacia: gram negative
*Aspergillus brasiliensis (formerly called A. niger): fungus (mold)
*Candida albicans: diploid fungus/yeast

The asterisks indicate the fungal strains that it was tested against.

Of course, if you want to be super sure, you can always opt for challenge testing your finished product for a new formulation.
In general, I’ve used essential oils to additionally preserve the creams, though my olive oil cream does not have e.o.’s. Essential oils with antimicrobial properties are numerous so here is a start:

Oregano essential oil
Sandalwood essential oil
-Thyme essential oil
-Lemongrass essential oil
-Bay essential oil

Also note that these have been found to have antimicrobial properties, yet their action within a cosmetic system (ie a cream formulation) may be different and that is why testing is so highly condoned. Most small scale producers cannot afford extensive testing so do what you can with the information!

Antioxidant Synergy Blend is a proprietary mixture of tocopherols (vitamin E), ascorbic acid (vitamin C) and rosemary extract. I like to add this to prevent rancidity in the oil portions of creams and sometimes in facial oils and other oil-based products. I’ve found that through The Herbarie which manufactures it.

Thanks so much,

Leave a Comment