Ferulic acid is an antioxidant found naturally in plant cell walls, leaves and seeds. A good amount of ferulic acid is found in oats, brown rice, whole wheat, peanuts, apples, and pineapples.

Health benefit of ferulic acid
Ferulic acid may be beneficial in the health of sperm and fertility.

Food Chem Toxicology. 2014. Ferulic acid: Pharmacological and toxicological aspects. FA belongs to the family of phenolic acids and is very abundant in fruits and vegetables. Over the past years, several studies have shown that FA acts as a potent antioxidant by scavenging free radicals and enhancing the cell stress response through the up-regulation of cytoprotective systems, e.g. heme oxygenase-1, heat shock protein 70, extracellular signal-regulated kinase 1/2 and the proto-oncogene Akt. Furthermore, FA was shown to inhibit the expression and/or activity of cytotoxic enzymes, including inducible nitric oxide synthase, caspases and cyclooxygenase-2. Based on this evidence, FA has been proposed as a potential treatment for many disorders including Alzheimer's disease, cancer, cardiovascular diseases, diabetes mellitus and skin disease. However, despite the great abundance of preclinical research, only a few studies were carried out in humans, the majority of which used foods containing FA, and therefore the clinical efficacy of this mode of administration needs to be further documented.

Brain cell protection
Iran J Basic Med Sci. 2015. Ferulic acid protects PC12 neurons against hypoxia by inhibiting the p-MAPKs and COX-2 pathways.

Chemistry
Ferulic acid is a ubiquitous plant constituent found in plant cell walls, leaves and seeds. It is made from the metabolism of phenylalanine and tyrosine. It occurs primarily in seeds and leaves both in its free form and covalently linked to lignin and other biopolymers. Due to its phenolic nucleus and an extended side chain conjugation, it readily forms a resonance stabilized phenoxy radical which accounts for its potent antioxidant potential. UV absorption by ferulic acid catalyzes stable phenoxy radical formation and thereby potentiates its ability to terminate free radical chain reactions. By virtue of effectively scavenging deleterious radicals and suppressing radiation-induced oxidative reactions, ferulic acid may serve an important antioxidant function in preserving physiological integrity of cells exposed to both air and impinging UV radiation. Similar photoprotection is afforded to skin by ferulic acid dissolved in cosmetic lotions. Its addition to foods inhibits lipid peroxidation and subsequent oxidative spoilage. By the same mechanism ferulic acid may protect against various inflammatory diseases. A number of other industrial applications are based on the antioxidant potential of ferulic acid.  

Ferulic acid and vanillin
Vanillin, vanillic and protocatechuic acids are catabolic products of ferulic acid degradation. Conversion of ferulic acid to vanillin occurs. Ferulic acid is similar to curcumin in chemical structure. Ferulic acid is a derivative of trans-cinnamic acid and a precursor to vanillin.

Ferulic acid in coffee
Coffee is particularly rich in bound phenolic acids, such as caffeic acid, ferulic acid, and p-coumaric acid. Chlorogenic acid (5'-caffeoylquinic acid), a bound form of caffeic acid, is present in coffee at high levels. Wheat bran contains several ester-linked dehydrodimers of ferulic acid.

Research
Amaranth as a rich dietary source of beta sitosterol and other phytosterols.
Plant Foods Hum Nutr. 2003.
The analysis of 4 commonly available amaranth varieties (Amaranthus K343, RRC1011, K433, K432) revealed the presence of all three major phytosterols (beta-sitosterol, campesterol, stigmas-terol) with a total sterol content being several fold higher than those found in other studied plants. Substantial differences in total phytosterol content and beta-sitosterol content were found between the amaranth varieties. The most commonly cultivated amaranth variety in the United States, i.e., Amaranthus K343 was found to possess the highest levels of phytosterols of the varieties tested. The possibility of screening for superior amaranth varieties with various health properties is outlined.

Ferulic acid is bound to the primary cell walls of all gymnosperm families.
Biochem Syst Ecol. 2000.
Unlignified primary cell walls containing ester-linked ferulic acid fluoresce blue in ultraviolet radiation which changes to green with increased intensity on treatment with ammonium hydroxide. Using this fluorescence behaviour, we detected ester-linked ferulic acid in the primary cell walls of all 41 species of gymnosperms we examined. These species were in 17 families representing all four extant classes of gymnosperms. In addition, we obtained cell-wall preparations containing >95% primary cell walls from nine gymnosperm species in nine families, representing all four extant classes. These preparations were analysed for ester-linked monomeric phenolic acids. We found ferulic acid (mostly trans) (88-1,561microg/g cell walls) in all of the preparations and p-coumaric acid (mostly trans) (0-106microg/g cell walls) in all except one of them. Ferulic acid ester-linked to primary cell walls has previously been found in angiosperms: in the commelinoid monocotyledons and in the dicotyledon order Caryophyllales, both monophyletic groups. From the present results, we postulate that the extant classes of gymnosperms are monophyletic and no class is sister to the angiosperms.

Reactivity of ferulic acid and its derivatives toward hydrogen peroxide and peracetic acid.
J Agric Food Chem. 1999.
The reactions of ferulic acid and its derivatives with hydrogen peroxide and peracetic acid in lignin-retaining bleaching conditions have been investigated to determine their susceptibility to oxidative degradation. The conjugated side chain of ferulic acid and its etherified or esterified derivative was shown to be fairly stable, especially to hydrogen peroxide. The major reaction was trans-cis isomerization that possibly involved a radical mechanism but did not cause bond cleavage. The peracetic acid reaction increased the rate of trans-cis isomerization and was also accompanied by a minor cleavage of the side chain. Esterification did not have a substantial effect on the reactivity of ferulic acid, but 4-O-etherification significantly stabilized it against these two oxidants. By contrast, aldehyde substitution tremendously enhanced the susceptibility of the cinnamyl side chain to oxidative degradation, as evidenced by an intensive degradation of coniferaldehyde.

Effects of ferulic acid on fertile and asthenozoospermic infertile human sperm motility, viability, lipid peroxidation, and cyclic nucleotides.
Free Radic Biol Med. 1997.
Department of Biology, Lanzhou University, P.R. China.
The capacity of human sperm fertilization principally depends on sperm motility and membrane integrity. Reactive oxygen species, such as superoxide anion and hydrogen peroxide, are known to impair sperm motility and membrane integrity by inducing membrane lipid peroxidation (LPO). Ferulic acid, an effective constituent in various medicinal herbs, has recently been shown to scavenge oxygen free radicals and increase the intracellular cAMP and cGMP. The aim of this study is to investigate the effects of ferulic acid on human sperm motility, viability, lipid peroxidation, and cyclic nucleotides in fertile and asthenozoospermic infertile individuals in vitro. The results showed: in both fertile and infertile spermatozoa, the viability, trans-membrane migration ratio (TMMR) and the levels of intracellular cAMP and cGMP in ferulic acid -treated spermatozoa were significantly higher than those of spermatozoa in control groups, while TBA-reactive substances contents in treated spermatozoa were significantly lower than those in control spermatozoa. The effects of ferulic acid on these processes were concentration dependent. These data suggested that ferulic acid is beneficial to sperm viability and motility in both fertile and infertile individuals, and that reduction of lipid peroxidative damage to sperm membranes and increase of intracellular cAMP and cGMP may be involved in these benefits. It is possible that ferulic acid may be used for cure of asthenozoospermic infertility.

Trans-4-hydroxy-3-methoxycinnamic acid (ferulic acid) inhibits the effect of androgens on the rat prostate.
Experientia. 1979.
Trans-4-hydroxy-3-methoxycinnamic acid antagonized the effect of exogenous androgens on the ventral prostate (VP) in castrated rats as well as the effect of endogenous androgens in intact rats. Ferulic acid, however, had no effect on the seminal vesicles (SV) and levator ani muscle (LAM), nor oestrogenic effect in female rats and mice. Ferulic acid did not antagonize the receptor binding of testosterone nor inhibit the conversion of testosterone into 5 alpha-dihydrotestosterone (DHT).