Hoya is a semi-woody, succulent perennial climibing vine. Leaves are glossy, waxy, succulent and grayish green, elliptic to broad-oval, up to 20 centimeters long. Flowers are in umbels, 3 to 5 inches in diameter, pinkish-white with a red star-shaped crown.
- Indigenous to Australia, China and the Philippines.
- Ornamental cultivation.
- Popular as a hanging pot plant.
• Flowers yielded volatile compounds, viz., methyl butanal, ethylbenzene, o-xylene, p-xylene, benzaldehyde, 6-methyl-5-heptan-2-one, benzyl alcohol, linalool, 2-nonen-1-ol, phenylethylalcohol and 2-(E)-noneal.
• Stem yielded oligosaccharides A, B, and C (1-3) established as 6-deoxy-3-O-methyl-β-allopyranosyl(1→4)-β-cymaropyranosyl (1→4)-β-cymaropyranosyl(1→4)-β-cymaronic acid δ-lactone (compound 1) and 6-deoxy-3-O-methyl-β-allopyranosyl(1→4)-β-oleandropyranosyl(1→4)-β-cymaropyranosyl(1→4)-β-cymaronic acid δ-lactone (compound 2). Compound 3 was the sodium salt of compound 2. (6)
• No reported folkloric medicinal use in the Philippines.
• Volatile Compounds:
Study isolated volatile compounds from the flowers of Hoya carnosa: methyl butanal, ethylbenzene, o-xylene, p-xylene, benzaldehyde, 6-methyl-5-heptan-2-one, benzyl alcohol, linalool, 2-nonen-1-ol, phenylethylalcohol and 2-(E)-noneal. (2)
• Air-Purifying Plant: In a University of Georgia study, Hoya carnaso was shown to be good at absorbing VOCs. VOCs are volatile organic compounds, contaminants emitted by various common household items. More than 300 have been identified – carpets, wood panels, paints, pets, formaldehyde, benzene and toluene from old books, newspapers, waxes and adhesives. (1)
• ADPglucose Pyrophosphorylase: ADPglucose pyrophosphorylase from Hoya carnosa and Xerosicyos danguyi were partially purified for their regulatory and kinetic properties. The ADPglucose synthesized by the enzymes was found to be the most effective donor of the glucosyl portion to alpha-glucan primer in starch synthase reaction observed in CAM plants. (1)
• Hemolytic Crises Caused by H. Carnosa in G6PD Deficiency: Study reports a hemolytic crises caused by contact with Hoya carnosa in a 45-year old woman with G6PD deficiency. (7)
• Use for Anti-Aging Benefits / Patent: Patent application relates to the incorporation of Hoya carnosa extracts and their use to reduce fine lines and wrinkles, improve saffing, enhance lifting, and improve skin tone and to improve overall appearance by increasing epidermis thickness and stimulating collagen, and/or inducing lipogenesis. (9)
• Can plants control indoor air pollution? Recent reports in the media and promotions by the decorative houseplant industry characterize plants as "nature's clean air machine", claiming that National Aeronautics and Space Administration (NASA) research shows plants remove indoor air pollutants. While it is true that plants remove carbon dioxide from the air, and the ability of plants to remove certain other pollutants from water is the basis for some pollution control methods, the ability of plants to control indoor air pollution is less well established. Most research to date used small chambers without any air exchange which makes extrapolation to real world environments extremely uncertain. The only available study of the use of plants to control indoor air pollutants in an actual building could not determine any benefit from the use of plants69. As a practical means of pollution control, the plant removal mechanisms appear to be inconsequential compared to common ventilation and air exchange rates. In other words, the ability of plants to actually improve indoor air quality is limited in comparison with provision of adequate ventilation.
While decorative foliage plants may be aesthetically pleasing, it should be noted that over damp planter soil conditions may actually promote growth of unhealthy microorganisms. (4)