Hydrangea common names hydrangea or hortensia, is a genus of 70–75 species of flowering plants native to Asia and the Americas. By far the greatest species diversity is in eastern Asia, notably Korea, China, and Japan. Most are shrubs 1 to 3 meters tall, but some are small trees, and others lianas reaching up to 30 m (98 ft) by climbing up trees. They can be either deciduous or evergreen, though the widely cultivated temperate species are all deciduous.
A pH indicator is a halochromic chemical compound added in small amounts to a solution so the pH (acidity or basicity) of the solution can be determined visually. Hence, a pH indicator is a chemical detector for hydronium ions (H3O+) or hydrogen ions (H+) in the Arrhenius model. Normally, the indicator causes the color of the solution to change depending on the pH. Indicators can also show change in other physical properties; for example, olfactory indicators show change in their odor. The pH value of a neutral solution is 7.0 at 25°C (standard laboratory conditions). Solutions with a pH value below 7.0 are considered acidic and solutions with pH value above 7.0 are basic (alkaline). As most naturally occurring organic compounds are weak protolytes, carboxylic acids and amines, pH indicators find many applications in biology and analytical chemistry. Moreover, pH indicators form one of the three main types of indicator compounds used in chemical analysis. For the quantitative analysis of metal cations, the use of complexometric indicators is preferred, whereas the third compound class, the redox indicators, are used in titrations involving a redox reaction as the basis of the analysis.
Hydrangea macrophylla is a species of flowering plant in the family Hydrangeaceae, native to Japan. It is a deciduous shrub growing to 2 m (7 ft) tall by 2.5 m (8 ft) broad with large heads of pink or blue flowers in summer and autumn. Common names include bigleaf hydrangea, French hydrangea, lacecap hydrangea, mophead hydrangea, penny mac and hortensia. It is widely cultivated in many parts of the world in many climates. It is not to be confused with H. aspera 'Macrophylla'.
Hydrangea quercifolia, commonly known as oakleaf hydrangea or oak-leaved hydrangea, is a species of flowering plant in the family Hydrangeaceae. It is native to the Southeastern United States, in woodland habitats from North Carolina west to Tennessee, and south to Florida and Louisiana. A deciduous shrub with white showy flower heads, it is a commonly grown garden plant. Numerous cultivars are available commercially.
Umbelliferone, also known as 7-hydroxycoumarin, hydrangine, skimmetine, and beta-umbelliferone, is a natural product of the coumarin family.
Hydrangea aspera is a species of flowering plant in the family Hydrangaceae, native to the region between the Himalayas, across southern China, to Taiwan. It is a large, erect deciduous shrub growing to 3 m (10 ft) tall and wide, with broadly oval leaves. The flowers are typically borne in large flat heads in late summer, and are in variable shades of pale blue and pink, fringed by white or pale pink sterile florets.
Hydrangea serrata is a species of flowering plant in the family Hydrangeaceae, native to mountainous regions of Korea and Japan. Common names include mountain hydrangea and tea of heaven. Growing to 1.2 m (4 ft) tall and broad, it is a deciduous shrub with oval leaves and panicles of blue and pink flowers in summer and autumn (fall). It is widely cultivated as an attractive ornamental shrub throughout the world in areas with suitable climate and soil.
Myrtillin is an anthocyanin. It is the 3-glucoside of delphinidin. It can be found in all green plants, most abundantly in blackcurrant, blueberry, huckleberry, bilberry leaves and in various myrtles, roselle plants, and Centella asiatica plant. It is also present in yeast and oatmeal. The sumac fruit's pericarp owes its dark red colour to anthocyanin pigments, of which chrysanthemin, myrtillin and delphinidin have yet been identified.
Hydrangenol is a dihydroisocoumarin. It can be found in Hydrangea macrophylla, as well as its 8-O-glucoside. (-)-hydrangenol 4'-O-glucoside and (+)-hydrangenol 4'-O-glucoside can be found in Hydrangeae Dulcis Folium, the processed leaves of H. macrophylla var. thunbergii.
Phyllodulcin is a dihydroisocoumarin found in Hydrangea macrophylla and Hydrangea serrata. It is a sweetener 400-800 times sweeter than sugar.
Thunberginol A is an isocoumarin found in Hydrangea macrophylla and the herbal preparation hydrangeae dulcis folium which is produced from its leaves.
Thunberginol B is an isocoumarin found in Hydrangeae Dulcis Folium, the processed leaves of Hydrangea macrophylla var. thunbergii.
Thunberginol C is a dihydroisocoumarin found in Hydrangeae Dulcis Folium, the processed leaves of Hydrangea macrophylla var. thunbergii.
Thunberginol D is a dihydroisocoumarin found in Hydrangeae Dulcis Folium, the processed leaves of Hydrangea macrophylla var. thunbergii.
Thunberginol E is a dihydroisocoumarin found in Hydrangeae Dulcis Folium, the processed leaves of Hydrangea macrophylla var. thunbergii.
Thunberginol F is a phthalide found in Hydrangea macrophylla.
Thunberginol G is a dihydroisocoumarin found in Hydrangeae Dulcis Folium, the processed leaves of Hydrangea macrophylla var. thunbergii.
Lunularic acid is a dihydrostilbenoid found in the liverwort Lunularia cruciata and in the roots of Hydrangea macrophylla.
3,4′-Dihydroxystilbene is a stilbenoid found in the roots of Hydrangea macrophylla.
Lunularin is a dihydrostilbenoid found in common celery. It has also been found in the roots of Hydrangea macrophylla.
