Raspberry ketone, also known as raspberry ketone, belongs to the flavonoid class of compounds. Its chemical name is p-hydroxyphenylbutanone, with a molecular weight of 164.22. It is a white, needle-like crystalline solid with a sweet fruity aroma, slightly soluble in water, and found in natural raspberry juice. It is an important aroma component of raspberry essential oil and a widely used fragrance both domestically and internationally, possessing an elegant fruity scent.
[Raspberry ketone structural formula: raspberry]
There are various methods for synthesizing raspberry ketone, such as using the petrochemical raw material p-hydroxybenzaldehyde and acetone (Figure 1). Natural-grade raspberry ketone can be prepared from natural anisaldehyde and fermented natural acetone through condensation, hydrogenation, and demethylation reactions (Figure 2).
With the further development of the fragrance industry and organic synthesis industry, the research value of raspberry ketone has steadily increased. Besides its use as a fragrance, it also has wide applications in other fields, such as cosmetics.
I. Preservative Efficacy Kong Qiuchan et al. studied the antibacterial properties of raspberry ketone and investigated the inhibitory effects of raspberry ketone combined with 1,2-hexanediol or phenoxyethanol on bacteria, yeasts, and molds. Table 1 shows the combined preservative schemes.
As shown in Table 2, #3 showed good inhibitory effects on bacteria and fungi on day 14, and #4 on day 7. However, when the content of the antibacterial component was low, the inhibitory effect of the system on Staphylococcus aureus and Candida albicans was slightly weaker. Table 2 Antibacterial properties of raspberry ketone and 1,2-hexanediol combination (logarithmic value)
As shown in Table 3, #7 showed good antibacterial effects on day 14, and #8 on day 7. However, when the content of the antibacterial component was low, the inhibitory effect of the system on Aspergillus niger and Candida albicans was slightly weaker. Table 3. Antibacterial Properties of Raspberry Ketone and Phenoxyethanol Combination (Logarithmic Value)
In summary, raspberry ketone has antibacterial effects, but its use alone is not recommended. It can be used in combination with 1,2-hexanediol or phenoxyethanol. For example, in emulsion or cream formulations, using 0.4% raspberry ketone combined with 0.5% 1,2-hexanediol or 0.2% phenoxyethanol can meet the product's preservative requirements.
II. Antioxidant Properties Lin Weikang et al. studied a low-cost preparation method for raspberry ketone and then evaluated its efficacy.
Figure 3. Effects of Different Drug Groups on ROS Levels in UVB-Induced Senescent HaCaT Cells In Figure 3, Normal represents the normal control group, Model represents the UVB model group (the aforementioned cell clusters were irradiated with UVB at a dose of 80 mJ/cm²), Positive control represents the positive control group, and Sample represents the raspberry ketone group.
As shown in Figure 3, compared with the normal control group, the intracellular ROS level in the UVB-irradiated model group was significantly increased. Compared with the model group, raspberry ketone significantly inhibited the increase in intracellular ROS level induced by UVB irradiation in senescent cells (P < 0.05), indicating that raspberry ketone has antioxidant activity and can also resist photoaging.
In summary, raspberry ketone is naturally derived, has a mild and unique odor, and can be used as a fragrance in cosmetics. Because it contains phenolic hydroxyl groups, raspberry ketone has certain antioxidant properties and is usually used as an antioxidant. However, due to its strong preservative effect, it is also often used as a preservative synergist (often used in combination with 1,2-hexanediol, pentanediol, caprylyl glycol, ethylhexylglycerin, etc. to replace traditional preservatives). It exhibits excellent stability across a wide range of pH and temperature. In addition, raspberry ketone alone has a good effect on skin whitening. When using a toner containing 0.1% to 3% raspberry ketone, the skin becomes bright and moist, and the wrinkles and sagging of the skin are significantly improved.
END References: [1] Hao Jiajin, Wang Bi, Yang Guangyuan, et al. Research progress of raspberry ketone [J]. Progress in Fine Petrochemicals, 2015, 16 (05): 48-50. [1] Gu Yuncui, Qian Liqun, Huan Yueqin, et al. Preparation of natural raspberry ketone [J]. Fragrance, Flavor and Cosmetics, 2013 (S1): 39-41+35. [1] Lin Weikang, Kang Le, Chen Yanxin, et al. Low-cost preparation method of natural active ingredient raspberry ketone and its efficacy evaluation [J]. Zhejiang Chemical Industry, 2023, 54 (04): 15-22+30. [1] Kong Qiuchan, Jiang Jiaxin, Xia Gaohui, et al. Study on the preservative effect of raspberry ketone in cosmetics [J]. China Detergent Industry, 2023 (04):54-61.
