Retinyl propionate is a synthetic derivative of a Vitamin A. Upon topical application, retinyl propionate is hydrolyzed by esterases to retinol, which is ultimately converted to retinoic acid. In mouse models, retinyl propionate induced epidermal thickening in mouse tail and promoted collagen formation in UV-irradiated mice. These results encouraged clinical trials of retinyl palmitate against photoaging. Topical retinyl propionate cream (0.15%) did not demonstrate any statistically significant improvement over placebo, but in later studies of combinations of retinyl propionate with climbazole or niacinamide improvements in the appearance of fine lines, wrinkles and age spots were demonstrated.

Stevioside is an ent-kaurene type diterpenoid glycoside isolated from leaves of Stevia rebaudiana (Bertoni) Bertoni, a perennial herb of the asteraceae (compositae) family. Stevioside and related compounds are responsible for the sweet taste of Stevia leaves. Stevioside is an intense sweetener and the extract of its source (S. rebaudiana) finds extensive use in countries like Japan, China, Russia, Korea, Paraguay, Argentina, Indonesia, Malaysia, Australia, New Zealand, South America, and others, to sweeten local teas, medicines, food, and beverages. Stevia leaves are also in use for their medicinal benefits in hypertension, obesity, topical dressing for wounds, and other skin disorders. Oral stevioside is not taken up by the human body (or the uptake is extremely low) and none of the digestive enzymes from the gastro-intestinal tract of different animals and human body are able to degrade stevioside into steviol. A number of studies have suggested that, beside sweetness, stevioside along with related compounds, which include rebaudioside A, steviol and isosteviol may also offer therapeutic benefits, as they have anti-hyperglycemic, anti-hypertensive, anti-inflammatory, anti-tumor, anti-diarrheal, diuretic, and immunomodulatory actions.

Palmatine is a protoberberine alkaloid. Palmatine is major component of herbal preparations mainly used in traditional medicine Chinese, Korean and Indian. Palmatine can be found in various medicinal plants such as Coptis chinensis, Rhizoma coptidis, Corydalis yanhusuo, Radix tinosporae, among others. It exerts diverse pharmacological and biological properties. Palmatine has been proposed as a promising DNA phototherapy drug, notably due to its ability to produce in situ singlet oxygen only when interacting with DNA.