phenolic acid
{{Short description|Class of chemical compounds}}
File:Salicylic-acid-skeletal.svg, a common phenolic acid]]
Phenolic acids or phenolcarboxylic acids ? {{Clarification needed|date=May 2025}}are phenolic compounds and types of aromatic acid compounds. Included in that class are substances containing a phenolic ring and an organic carboxylic acid function (C6-C1 skeleton). Two important naturally occurring types of phenolic acids are hydroxybenzoic acids and hydroxycinnamic acids, which are derived from non-phenolic molecules of benzoic and cinnamic acid, respectively.{{Cite journal|last1=Heleno|first1=Sandrina A.|last2=Martins|first2=Anabela|last3=Queiroz|first3=Maria João R. P.|last4=Ferreira|first4=Isabel C. F. R.|date=2015-04-15|title=Bioactivity of phenolic acids: metabolites versus parent compounds: a review|journal=Food Chemistry|volume=173|pages=501–513|doi=10.1016/j.foodchem.2014.10.057|issn=0308-8146|pmid=25466052|hdl=1822/39808|url=http://repositorium.sdum.uminho.pt/bitstream/1822/39808/1/Bioactivity%20of%20phenolic%20acids.pdf|hdl-access=free}}
Occurrences
Phenolic acids can be found in many plant species. Their content in dried fruits can be high.
Natural phenols in horse grams (Macrotyloma uniflorum) are mostly phenolic acids, namely 3,4-dihydroxy benzoic, p-hydroxy benzoic, vanillic, caffeic, p-coumaric, ferulic, syringic, and sinapinic acids.{{Citation needed|date=December 2019|reason=removed citation to predatory publisher content}}
Phenolic acids can be found in several mushroom-forming species of basidiomycetes.{{ cite journal | title = Phenolic acids determination by HPLC–DAD–ESI/MS in sixteen different Portuguese wild mushrooms species |author1=Barros, L. |author2=Dueñas, M. |author3=Ferreira, I. C. |author4=Baptista, P. |author5=Santos-Buelga, C. | journal = Food and Chemical Toxicology | volume = 47 | issue = 6 | date = June 2009 | pages = 1076–1079 | doi = 10.1016/j.fct.2009.01.039 | pmid = 19425182 |hdl=10198/2650 }} It is also a part of the humic substances, which are the major organic constituents of soil humus.{{Citation needed|date=May 2025}}
Many phenolic acids can be found in human urine.{{ cite journal | title = The phenolic acids of human urine. Paper chromatography of phenolic acids |author1=Armstrong, M. D. |author2=Shaw, K. N. |author3=Wall, P. E. | journal = The Journal of Biological Chemistry | date = January 1, 1956 |volume = 218 |issue=1 | pages = 293–303 |doi=10.1016/S0021-9258(18)65893-4 |doi-access=free | url = http://www.jbc.org/content/218/1/293.full.pdf | pmid = 13278337 }}
Chemistry
Immobilized Candida antarctica lipase can be used to catalyze the direct acetylation of flavonoids with phenolic acids.{{cite journal |title=Direct acylation of flavonoid glycosides with phenolic acids catalysed by Candida antarctica lipase B (Novozym 435®) |first1=David E. |last1=Stevenson |first2=Reginald |last2=Wibisono |first3=Dwayne J. |last3=Jensen |first4=Roger A. |last4=Stanley |first5=Janine M. |last5=Cooney |journal=Enzyme and Microbial Technology |date=3 October 2006 |volume=39 |issue=6 |pages=1236–41 |doi=10.1016/j.enzmictec.2006.03.006}}