hydroxy acid
Học thuậtThân thiện
Definition
- Noun:
- A type of organic acid: A hydroxy acid is any acid that contains one or more hydroxyl (-OH) groups in its molecular structure, in addition to the hydroxyl group that is part of the characteristic carboxylic acid (-COOH) group itself.
Usage and Examples
- Noun:
- Alpha hydroxy acids, like glycolic acid, are common ingredients in skincare products for exfoliation.
- Citric acid, found in citrus fruits, is a well-known hydroxy acid.
- The chemist synthesized a new hydroxy acid for the experiment.
Advanced Usage and Notes
- Hydroxy acids are classified into subgroups based on the position of the hydroxyl group relative to the carboxylic acid group. The two primary categories are:
- Alpha hydroxy acids (AHAs): The hydroxyl group is on the carbon atom adjacent (alpha) to the carboxyl group. Examples include glycolic acid and lactic acid.
- Beta hydroxy acids (BHAs): The hydroxyl group is on the second carbon atom (beta) from the carboxyl group. Salicylic acid is a common example.
- In biochemistry, many hydroxy acids are important intermediates in metabolic cycles, such as the citric acid cycle.
Variants and Related Words
- Alpha hydroxy acid (AHA) (n): A subclass of hydroxy acids used extensively in cosmetics and dermatology.
- Beta hydroxy acid (BHA) (n): A subclass of hydroxy acids, with salicylic acid being the most prominent member, often used for its ability to penetrate oily skin.
- Carboxylic acid (n): The broader class of organic acids containing a carboxyl (-COOH) group, to which hydroxy acids belong.
- Hydroxyl group (n): The functional group consisting of an oxygen atom bonded to a hydrogen atom (-OH).
Synonyms and Related Terms
- Hydroxylated acid: A less common term with the same meaning.
- Polyhydroxy acid: A hydroxy acid containing multiple hydroxyl groups.
Common Phrases and Contexts
- Hydroxy acid peel: A cosmetic procedure using a concentrated solution of hydroxy acids to improve skin texture.
- Fruit acid: A common marketing term for alpha hydroxy acids derived from fruit sugars, such as glycolic acid (from sugar cane) or malic acid (from apples).
Noun
- any acid that has hydroxyl groups in addition to the hydroxyl group in the acid itself