Summary of a doctoral dissertation of Renata Prusinowska M.Sc., Eng
New and innovative products from lavender (Lavandula angustifolia)
for cosmetic industry
It has been shown that narrow-leaved lavender (Lavandula angustifolia) grown in Poland, is a valuable raw material for obtaining components with good sensory and biological properties - both traditional essential oilsand new products - variants of hydrolates
orinnovative - fluidolates.
UV/VIS spectroscopy, near-infrared spectroscopy (NIR), gas chromatography (GC) and gas chromatography coupled with mass spectrometry (GC/MS) were used in the study.
It has been found that essential oils from fresh or dried flowers or lavenderherb differ,
to small extent, in chemical composition. The main compoundsinclude linalool (26.5-34.7%), linalyl acetate (19.7-23.4%), terpinene-4-ol (2.0-4.9%), α-terpineol (2.8-5.1%), β-ocimene (2.9-10.7%), and geranyl acetate (1.7-2.8%). Conventional drying of flowers or lavender herb resulted in a loss of approx. 36% to 45% of volatile organic compounds. The content
of essential oil in lavender is in line with the criteria of European Pharmacopoeia 8.0
(1.11%-1.16%) and at a similar level as in the raw materials of crop production in France (0.32-2.00%) and Bulgaria (1.25%-1.30%). The profile of organic compounds in the essential oils of lavender, as determined by near-infrared spectroscopy (NIR), was most similar,
in a sensory way, to the best oil from France (correlation coefficient of 90.39%).
Lavender essential oils, in the opinion of the Analysis Team, had a characteristic scentstructureof the fresh lavender with the green heart and the herb note; the oil of fresh flowers was considered as the most attractive.
Antimicrobial activity of essential oils from fresh or dried flowers or lavender herb was determined in relation to strains of Gram-negative (Escherichia coli, Pseudomonas aeruginosa) and Gram-positive bacteria (Staphylococcus aureus, Bacillus subtilis) as well asCandida albicansyeast and Aspergillus niger and Penicillium expansum molds. It has been found that essential oils exhibit high activity against Gram-positive and Gram-negative bacteria, and growth inhibition occurred at a concentration of 0.4-2.0 μL/mL. Essential oils showed much better activity against the Candida sp. yeast, and the MIC values were 1.5-5 times lower than those of bacteria. Aspergillus niger and Penicillium expansummolds had different resistivity, from MIC=2 μL/mLfor essential oil of dried flowers to MIC=5 μL/mL for fresh flowers or fresh or dried herb.
Antioxidant activity of essential oils of lavender has been shownby determining the ability to scavenge free radicals (DPPH method). The strongest antioxidant properties were found
in essential oil from fresh herb (IC50 of 180 mg/L) and the weakest - in the dried herb (IC50 513 mg/L).
In the process of the preparation of essential oils by steam distillation, the product referred to as hydrolate is also obtained. In the technologies used currently, only one type
of component is obtained, and the sensory evaluation is the only criterion for quality. For the isolation of organic compounds from aqueous matrix, liquid-liquid extraction (LLE)
or a dispersion liquid-liquid microextraction (DLLME) method was used. For both analytical procedures, on the basis of the statistical tool (Taguchi model), the optimal extraction conditions giving the greatest recovery of volatile compounds from an aqueous matrix were determined. 96.68±2.06% in theLLE method and 98±1.2% in the DLLME method of organic compounds was recovered in the hydrolate model. It has been shown that the sensory properties and biological activity of lavender hydrolates depend on both the volume
(400-1600 mL) ofplant material extracted from the weight unit of and the form (flowers, herbs). The main compounds in hydrolatesinclude linalool (24.2-53.0% LLE; 25.7-60.5% DLLME), terpinene-4-ol (LLE 2.9-8.0%, 3.7-9.6% DLLME), borneol (3.1-10.7% LLE; DLLME 0.9-7.7%) and α-terpineol (4.1-8.8% LLE; 4.1-10.6% DLLME). Linalyl acetate, present in the essential oil of lavender, has not been found. The highest content of volatile organic compounds was found in dried flowers hydrolate of 400 mL, from 660 µg/mL
of hydrolate to 712 µg/mL of hydrolate, including linalool 279-288 µg/mL of hydrolate, and the lowest in 1600 mL of dried herb, 96-105 µg/mL of hydrolate, including linalool 45-46 µg/mL of hydrolate.
The Analysis Team has ratedhydrolate variants of 400 mL, regardless of the form of raw material (flowers, herbs) and the method of preparation (fresh, dried) as the most valuable in terms of sensory qualities - fresh, floral, green, fruity. Hydrolates at the volume of 1600 mLwere considered the least attractive in terms of scent.
The strongest antioxidant activity, defined as the ability to deactivate ABTS•+cation radicals (ABTS method)was exhibited by the400 mLhydrolate of dried lavender flowers, 23% of ABTS cation radicals deactivation and the lowest by the 1600 mLhydrolates of dried herb with 9% deactivation of ABTS cation radicals.
Antimicrobial activity of lavender hydrolates has been determined both by disc diffusion and the dilution method. Variants of 400 mL or 800 mLfrom dried herb inhibited the growth of Candida yeasts in a small extent. 400 mLhydrolate of dried herb had the best antimicrobial properties and inhibited the growth of the Escherichia coli, Staphylococcus aureus and Bacillus subtilisbacteria already at a concentration of 1%,the hydrolate volume of 1600 mL of dried herb had no antibacterial and antifungal properties. In order to evaluate the antimicrobial properties of hydrolates in cosmetic products, moisturizing gels with addition
of selected components (400 mL, fresh or dried flowers or herbs) were prepared.
The cosmetic preparations contaminated with Staphylococcus aureus or Escherichia coli where, instead of water, dried flowers 400 mL hydrolate was added, showed no bacteria presentafter 14 and 7 days, respectively. The gels contaminated with Candida sp.
or Aspergillus niger, no viable cells were observed after two days. Cosmetics contaminated with Staphylococcus aureus or Escherichia colicontaining dried herb hydrolate(400 mL) exhibited no bacterial growth after 28 days.
According to the Analysis Team, cosmetic preparations with introduced 400 mL lavender hydrolates of fresh lavender flowers or dried herb were the most attractive, both in the sensory and hedonistic evaluation.
Comparing the yield of the essential oil from fresh or dried lavender,it has been found that the drying process before the isolation step resulted in 40% loss of the component. This observation was the basis for the development of innovative technology of drying the plant materials. Aso-far unknown component was achieved, defined as fluidolate®. The new product is condensed or resublimated water collected from the plant material, comprising biologically active volatile substances lost in the conventional drying procedures. The process was conducted in a closed circuit of the drying agent, at temperatures of from -10 to 50°C and a water loss from 25% to 85% of the raw material. 550 g of lavender herb was processed to achieve from 103 mL to 356 mLof fluidolate. The component did not contain the process water, the main component of hydrolates but only lavender water.
Main compounds in fluidolatesinclude linalool (38.6%-83.5%), α-terpineol (0.3%-14.3%) lavandulol (0.4%-8.6%) octan-3-on (0.4% -4.0%) and coumarin (0.2 to 21.8%), not revealed in essential oils and hydrolates. In the fluidolate obtained at drying medium temperature
of 30°C and 55% water loss, there was the highest amount of volatile organic compounds 817.6µg/mL of fluidolate including linalool 624.6 µg/mLof fluidolate, and thelowest
at -10°C and 55% water loss - 149.7µg/mL of fluidolate including linalool 107.5 µg/mL
of fluidolate.
Fluidolates have natural floral-herbal scent similar to the best, in the sensory evaluation, hydrolates. The components from the raw materials of 25% water loss had a fresh and green structureof fresh lavender. Fluidolates with 55% or 85% of water removed from the raw material, at all test temperatures of the drying agent, were considered as the most appealing
in a sensory attractive manner (herbal, floral, fresh and green).
For the evaluation of antimicrobial properties, agar diffusion method was used. Fluidolatewhich was obtained at 30°C and 85% water loss inhibited the growth of Escherichia coli and Staphylococcus aureusbacteria and Candida sp. and Aspergillus nigerfungi already at 10% of the sample. The component had the greatest amount of coumarinof 21.8% in volatile organic compounds. The fluidolate that was least effective against these microorganisms was obtained at 50°C and 55% water loss containing 0.2% of coumarin, as the inhibition percentage at the highest concentration (30%) was below 20. It has been found that Bacillus subtilis were least sensitive to all tested components.
The evaluation of antioxidant properties of fluidolateswas determined by their ability
to inactivate ABTS•+cation radicals. The greatest antioxidant properties were exhibited
by the fluidolate which was obtained at a temperature of -10°C and 25% water loss (51% inhibition), and the lowest at 50°C and 85% water loss (12% inhibition).
Components of lavender, both traditional - essential oils and new - hydrolates or innovative - fluidolatesperform sensory functions and constitute natural antimicrobial and antioxidant agents. Studies of the functional properties of the products obtained from thenarrow-leaved lavender (Lavandula angustifolia) grown in Poland indicate that small companies engaged
in the production of plant materials, due toconsiderable possibilities of the science-to-business technology transfer andjust-in-time production, have the conditions for the growth of financial efficiency and improvement of competitiveness, thus creating the strategy for their own success.
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