Butyric acid (butanoic acid) belongs to a group of short-chain fatty acids and is thought to play several beneficial roles in the gastrointestinal tract. The butyric anion is easily absorbed by enteric cells and used as a main source of energy. Moreover, butyric acid is an important regulator of colonocyte proliferation and apoptosis, gastrointestinal tract motility and bacterial microflora composition in addition to its involvement in many other processes including immunoregulation and anti-inflammatory activity. Butyric acid shows a protective effect in inflammatory response secondary to inflammatory bowel diseases. A beneficial effect of butyric acid as one constituent of a multifaceted mechanism modulating gastrointestinal function has also been stressed in patients with the stoma and coexisting constipation. Butyric acid supplementation combined with the use of probiotics should be adopted as one of the basic therapeutic strategies in this patient group, preceding treatment with laxatives. Sodium butyrate in the form of enemas (combined in a mixture with A-300 silicon dioxide) may be a successful method of therapeutic management in patients with radiation proctitis. Sodium butyrate may also prevent diarrhea through an increased passive absorption of water in the colon and its effects on the gut microflora.

Orotic acid is a minor dietary constituent. Historically it was believed to be part of the vitamin B complex and was called vitamin B13, but it is now known that it is not a vitamin and is synthesized in the body, where it arises as an intermediate in the pathway for the synthesis of pyrimidine nucleotides. Orotic acid is converted to UMP by UMP synthase, a multifunctional protein with both orotate phosphoribosyl transferase and orotidylate decarboxylase activity. The most frequently observed inborn error of pyrimidine nucleotide synthesis is a mutation of the multifunctional protein UMP synthase. As a result, plasma orotic acid accumulates to high concentrations, and increased quantities appear in the urine. Orotic acid levels are elevated in the urea cycle defects ornithine transcarbamylase (OTC) deficiency, citrullinemia and argininosuccinic acidemia, as well as the mitochondrial transport disorder hyperornithinemia-hyperammonemia-homocitrullinuria (HHH) syndrome. Orotic acid is also elevated in hereditary orotic aciduria, or uridine monophosphate synthase deficiency, an autosomal recessive disorder characterized by megaloblastic anemia and crystalluria. In addition, orotic acid in combination with leflunomide is in the phase II of clinical trial to evaluate the clinical efficacy and safety of a combination in kidney transplant patients with high levels of Polyoma BK viruria for the purpose of preventing polyoma BK viremia and nephropathy, that could lead to kidney transplant loss from viral damage, acute rejection or both.

Shikimic acid (SA), an active metabolite of polyphenol-rich food intake, originally extracted from Illicium verum Hook. fil. is an indispensable starting material for the synthesis of the antiviral drug oseltamivir and others useful compounds. In the biological studies, SA has been reported to have anti-inflammatory, analgesia, antioxidant, antithrombotic, and antibacterial activities. SA can play an important role in reducing platelet activation, aggregation related thrombus formation and biomarkers of thrombogenesis in sedentary individuals. In addition, was investigated antibacterial activity of SA against S. aureus, which could be caused by the interactions of SA with S. aureus membrane proteins and lipids, resulting in causing cell membrane dysfunction and bacterial damage or even death.

Caffeic acid is an organic compound that is classified as a hydroxycinnamic acid. Caffeic acid is naturally found in many agricultural products, such as fruit, vegetables, wine, olive oil, and coffee, and therefore, significantly present in human diet. Caffeic acid has been reported to have a wide variety of biological activities, including antioxidants, antithrombosis, antihypertensive, antifibrosis, antiviral and anti-tumor properties. Caffeic acid can be effectively employed as a natural antioxidant in various food products such as oils. Caffeic acid exhibits potent anticancer effect in HT-1080 cell line and that it may be used as an anticancer agent. Caffeic acid showed neuroprotective action against oxidative and DNA damage produced in the kindling epilepsy model, although they did not produce antiepileptogenic effect in vivo. Caffeic acid was effective in patients with primary immune thrombocytopenia. Detected in clinical trial caffeic acid-related adverse events were: mild nausea and elevation of liver enzymes.

Gamolenic acid also known as gamma-linolenic acid is a natural component of Oenothera biennis L. (Evening Primrose). Gamolenic acid was used for the treatment of breast painand atopic dermatitis in Europe, although now the drug is withdrawn from the market (there is no safety issue associated with the withdrawal of the licences). The mechanism of action of gamolenic acid is connected with its interaction with prostanoid pathway.

Cinnamic acid is a polyphenol found in cinnamon oil and used in commercial flavorings. Recent studies have shown the pharmacological properties of cinnamic acid and its derivatives, including hepatoprotective, anti-oxidant, and anti-diabetic activities. In preclinical studies cinnamic acid demonstrated to be a promising candidate for the treatment ob obesity and diabetes. The mechanism of action of cinnamic acid in obesity is explained by its ability to inhibit lipases and ACE (angiotensin-converting enzyme). However, there are several hypotesis regarding the effect of cinnamic acid in diabetes: cinnamic acid enhances glucose-induced insulin secretion, prevents palmitic acid-induced lipotoxicity, inhibits palmitic acid-induced alteration of lipogenic gene and protein expression (AMPK, SREBP-1c, FAS, ACC), inhibits DPP IV, exhibits an additive effect on the uptake of glucose, stimulates adiponectin secretion, etc.

Uric acid, generated from the metabolism of purines, has proven and emerging roles in human disease. Humans produce large quantities of uric acid. Excess serum accumulation of uric acid can lead to a type of arthritis known as gout. Hyperuricemia may increase risk factors for cardiovascular disease. High serum uric acid was associated with higher risk of type 2 diabetes and other diseases.

Palmitoleic acid, commonly known as omega-7, is a rare monounsatured fatty acid, which was generally reported to benefit the skin in promoting epithelialisation, and certain gynaecological problems (vaginal mycoses). Until now, sea buckthorn (Hippophae rhamnoides), a shrub widely found in Europe and Asia, and macadamia nuts have been the principal sources. Palmitoleic acid (PMA) has anti-inflammatory and antidiabetic activities. Palmitoleic acid is a gap junction uncoupler.

Glucuronic acid is a sugar acid that was first identified in urine. It is an intermediate metabolite of the uronic acid pathway. Moreover, glucuronic acid is involved in detoxification of certain drugs and toxins by conjugating with them and forming glucuronides. Glucuronic acid has been found to cause an increase in TLR4-dependent reporter protein expression in a cell line transfected with TLR4 and associated co-signaling molecules, and can cause TLR4-dependent pain in humans.