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56-411: Benzoic acid occurs naturally in many plants and serves as an intermediate in the biosynthesis of many secondary metabolites . Salts of benzoic acid are used as food preservatives . Benzoic acid is an important precursor for the industrial synthesis of many other organic substances. The salts and esters of benzoic acid are known as benzoates ( / ˈ b ɛ n z oʊ . eɪ t / ). Benzoic acid

112-656: A Polish botanist Friedrich Czapek described secondary metabolites as end products of nitrogen metabolism . Secondary metabolites commonly mediate antagonistic interactions, such as competition and predation , as well as mutualistic ones such as pollination and resource mutualisms . Usually, secondary metabolites are confined to a specific lineage or even species, though there is considerable evidence that horizontal transfer across species or genera of entire pathways plays an important role in bacterial (and, likely, fungal) evolution. Research also shows that secondary metabolism can affect different species in varying ways. In

168-423: A chemical compound characterized by the presence of aromatic ring structure bearing one or more hydroxyl groups . Phenolics are the most abundant secondary metabolites of plants ranging from simple molecules such as phenolic acid to highly polymerized substances such as tannins . Classes of phenolics have been characterized on the basis of their basic skeleton. An example of a plant phenol is: Alkaloids are

224-590: A diverse group of nitrogen-containing basic compounds. They are typically derived from plant sources and contain one or more nitrogen atoms. Chemically they are very heterogeneous. Based on chemical structures, they may be classified into two broad categories: Examples of alkaloids produced by plants are: Many alkaloids affect the central nervous system of animals by binding to neurotransmitter receptors . Glucosinolates are secondary metabolites that include both sulfur and nitrogen atoms , and are derived from glucose , an amino acid and sulfate . An example of

280-474: A glucosinolate in plants is Glucoraphanin , from broccoli ( Brassica oleracea var. italica ). Many drugs used in modern medicine are derived from plant secondary metabolites. The two most commonly known terpenoids are artemisinin and paclitaxel . Artemisinin was widely used in Traditional Chinese medicine and later rediscovered as a powerful antimalarial by a Chinese scientist Tu Youyou . She

336-761: A large class of natural products which are composed of isoprene units. Terpenes are only hydrocarbons and terpenoids are oxygenated hydrocarbons. The general molecular formula of terpenes are multiples of (C 5 H 8 ) n, where 'n' is number of linked isoprene units. Hence, terpenes are also termed as isoprenoid compounds. Classification is based on the number of isoprene units present in their structure. Some terpenoids (i.e. many sterols ) are primary metabolites. Some terpenoids that may have originated as secondary metabolites have subsequently been recruited as plant hormones, such as gibberellins , brassinosteroids , and strigolactones . Examples of terpenoids built from hemiterpene oligomerization are: Phenolics are

392-458: A medium-high temperature. Use of supercritical water instead of acetic acid as a solvent diminishes environmental impact and offers a cost advantage. However, the scope of such reaction systems is limited by the even more demanding conditions than the industrial process (300–400 °C, >200 bar). As with any large-scale process, many additives have been investigated for potential beneficial effects. Promising results have been reported with

448-402: A methyl group, which have weaker C–H bonds than does the aromatic ring. Many intermediates have been isolated. p -xylene is converted to p -toluic acid , which is less reactive than the p-xylene owing to the influence of the electron-withdrawing carboxylic acid group. Incomplete oxidation produces 4-carboxybenzaldehyde (4-CBA), which is often a problematic impurity. Approximately 5% of

504-418: A narrow set of species within a phylogenetic group. Secondary metabolites often play an important role in plant defense against herbivory and other interspecies defenses. Humans use secondary metabolites as medicines, flavourings, pigments, and recreational drugs. The term secondary metabolite was first coined by Albrecht Kossel , the 1910 Nobel Prize laureate for medicine and physiology. 30 years later

560-448: A preservative in food are between 0.05 and 0.1%. Foods in which benzoic acid may be used and maximum levels for its application are controlled by local food laws. Concern has been expressed that benzoic acid and its salts may react with ascorbic acid (vitamin C) in some soft drinks, forming small quantities of carcinogenic benzene . Benzoic acid is a constituent of Whitfield's ointment which

616-543: A regenerative source of free radicals . Acetic acid is the solvent and compressed air serves as the oxidant. The combination of bromine and acetic acid is highly corrosive , requiring specialized reactors, such as those lined with titanium . A mixture of p -xylene , acetic acid , the catalyst system, and compressed air is fed to a reactor. The oxidation of p -xylene proceeds by a free radical process. Bromine radicals decompose cobalt and manganese hydroperoxides. The resulting oxygen-based radicals abstract hydrogen from

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672-492: A significantly lower tolerance against benzoic acid and its salts than rats and mice . Lethal dose for cats can be as low as 300 mg/kg body weight. The oral LD 50 for rats is 3040 mg/kg, for mice it is 1940–2263 mg/kg. In Taipei , Taiwan, a city health survey in 2010 found that 30% of dried and pickled food products had benzoic acid. Secondary metabolite Secondary metabolites , also called specialised metabolites or secondary products , are

728-518: A subsidiary of McDermott International ) has reported a route from the dinitrile, which can be obtained by ammoxidation of p -xylene. Virtually the entire world's supply of terephthalic acid and dimethyl terephthalate are consumed as precursors to polyethylene terephthalate (PET). World production in 1970 was around 1.75 million tonnes. By 2006, global purified terephthalic acid (PTA) demand had exceeded 30 million tonnes. A smaller, but nevertheless significant, demand for terephthalic acid exists in

784-442: A tissue plant culture, such as jasmonic acid , UV-B or ozone . These compounds induce stress onto a plant leading to increased production of secondary metabolites. To further increase the yield of SMs new approaches have been developed. A novel approach used by Evolva uses recombinant yeast S. cerevisiae strains to produce secondary metabolites normally found in plants. The first successful chemical compound synthesised with Evolva

840-490: A type of natural product (organic compounds produced by living organisms) generated by lifeforms (e.g., bacteria , archaea , fungi , plants , or animals ) that are not directly involved in the normal growth , development , or reproduction of the organism. Instead, they generally mediate ecological interactions , which may produce a selective advantage for the organism by increasing its survivability or fecundity . Specific secondary metabolites are often restricted to

896-598: A yield of around 65%. Like other nitriles and amides , benzonitrile and benzamide can be hydrolyzed to benzoic acid or its conjugate base in acid or basic conditions. Bromobenzene can be converted to benzoic acid by "carboxylation" of the intermediate phenylmagnesium bromide . This synthesis offers a convenient exercise for students to carry out a Grignard reaction , an important class of carbon–carbon bond forming reaction in organic chemistry. Benzyl alcohol and benzyl chloride and virtually all benzyl derivatives are readily oxidized to benzoic acid. Benzoic acid

952-596: Is penicillin discovered by Alexander Fleming in 1928. Later in 1945, Fleming, alongside Ernst Chain and Howard Florey , received a Nobel Prize for its discovery which was pivotal in reducing the number of deaths in World War II by over 100,000. Examples of other fungal secondary metabolites are: Lovastatin was the first FDA approved secondary metabolite to lower cholesterol levels. Lovastatin occurs naturally in low concentrations in oyster mushrooms , red yeast rice , and Pu-erh . Lovastatin's mode of action

1008-650: Is a cardiac glycoside first derived by William Withering in 1785 from the foxglove (Digitalis) plant. It is typically used to treat heart conditions such as atrial fibrillation , atrial flutter or heart failure . Digoxin can, however, have side effects such as nausea , bradycardia , diarrhea or even life-threatening arrhythmia . The three main classes of fungal secondary metabolites are: polyketides , nonribosomal peptides and terpenes . Although fungal secondary metabolites are not required for growth they play an essential role in survival of fungi in their ecological niche. The most known fungal secondary metabolite

1064-655: Is a phenolic compound of the flavonoid class. It is highly abundant in grapes , blueberries , raspberries and peanuts . It is commonly taken as a dietary supplement for extending life and reducing the risk of cancer and heart disease, however there is no strong evidence supporting its efficacy. Nevertheless, flavonoids are in general thought to have beneficial effects for humans. Certain studies shown that flavonoids have direct antibiotic activity. A number of in vitro and limited in vivo studies shown that flavonoids such as quercetin have synergistic activity with antibiotics and are able to suppress bacterial loads. Digoxin

1120-460: Is also enhanced in the CO 2 environment. Because more oxygen is available to the system, supercritical carbon dioxide ( T c = 31 °C) has more complete oxidation with fewer byproducts, lower carbon monoxide production, less decarboxylation and higher purity than the commercial process. In supercritical water medium, the oxidation can be effectively catalyzed by MnBr 2 with pure O 2 in

1176-488: Is also formed in apples after infection with the fungus Nectria galligena . Among animals, benzoic acid has been identified primarily in omnivorous or phytophageous species, e.g., in viscera and muscles of the rock ptarmigan ( Lagopus muta ) as well as in gland secretions of male muskoxen ( Ovibos moschatus ) or Asian bull elephants ( Elephas maximus ). Gum benzoin contains up to 20% of benzoic acid and 40% benzoic acid esters. In terms of its biosynthesis , benzoate

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1232-423: Is also the so-called " Henkel process" or "Raecke process", named after the company and patent holder, respectively. This route involves the transfer of carboxylate groups. Either potassium benzoate disproportionates to potassium terephthalate and benzene or potassium phthalate rearranges to the terephthalate. Phthalic anhydride can be used as a raw material and then potassium can be recycled. Lummus (now

1288-589: Is also used in the production of PBT plastic (polybutylene terephthalate) . Terephthalic acid was first isolated (from turpentine) by the French chemist Amédée Cailliot (1805–1884) in 1846. Terephthalic acid became industrially important after World War II . Terephthalic acid was produced by oxidation of p -xylene with 30-40% nitric acid . Air oxidation of p -xylene gives p -toluic acid , which resists further air-oxidation. Esterification of p -toluic acid to methyl p-toluate (CH 3 C 6 H 4 CO 2 CH 3 ) opens

1344-420: Is also used to treat shortness of breath and treatment of addiction to stronger opiates such as heroin . Despite its positive effects on humans, morphine has very strong adverse effects, such as addiction, hormone imbalance or constipation. Due to its highly addictive nature morphine is a strictly controlled substance around the world, used only in very severe cases with some countries underusing it compared to

1400-538: Is competitive inhibition of HMG-CoA reductase , and a rate-limiting enzyme responsible for converting HMG-CoA to mevalonate . Fungal secondary metabolites can also be dangerous to humans. Claviceps purpurea , a member of the ergot group of fungi typically growing on rye, results in death when ingested. The build-up of poisonous alkaloids found in C. purpurea lead to symptoms such as seizures and spasms , diarrhea , paresthesias , Itching , psychosis or gangrene . Currently, removal of ergot bodies requires putting

1456-539: Is excreted as hippuric acid . Benzoic acid is metabolized by butyrate-CoA ligase into an intermediate product, benzoyl-CoA , which is then metabolized by glycine N -acyltransferase into hippuric acid. Humans metabolize toluene which is also excreted as hippuric acid. For humans, the World Health Organization 's International Programme on Chemical Safety (IPCS) suggests a provisional tolerable intake would be 5 mg/kg body weight per day. Cats have

1512-474: Is mainly consumed in the production of phenol by oxidative decarboxylation at 300−400 °C: The temperature required can be lowered to 200 °C by the addition of catalytic amounts of copper(II) salts. The phenol can be converted to cyclohexanol , which is a starting material for nylon synthesis. Benzoate plasticizers , such as the glycol-, diethyleneglycol-, and triethyleneglycol esters, are obtained by transesterification of methyl benzoate with

1568-482: Is now produced synthetically. Benzoic acid is cheap and readily available, so the laboratory synthesis of benzoic acid is mainly practiced for its pedagogical value. It is a common undergraduate preparation. Benzoic acid can be purified by recrystallization from water because of its high solubility in hot water and poor solubility in cold water. The avoidance of organic solvents for the recrystallization makes this experiment particularly safe. This process usually gives

1624-470: Is produced in plants from cinnamic acid . A pathway has been identified from phenol via 4-hydroxybenzoate . Reactions of benzoic acid can occur at either the aromatic ring or at the carboxyl group . Electrophilic aromatic substitution reaction will take place mainly in 3-position due to the electron-withdrawing carboxylic group ; i.e. benzoic acid is meta directing . Reactions typical for carboxylic acids apply also to benzoic acid. It

1680-663: Is the main method of production. Atropine is an alkaloid first found in Atropa belladonna , a member of the nightshade family . While atropine was first isolated in the 19th century, its medical use dates back to at least the fourth century B.C. where it was used for wounds, gout, and sleeplessness. Currently atropine is administered intravenously to treat bradycardia and as an antidote to organophosphate poisoning . Overdosing of atropine may lead to atropine poisoning which results in side effects such as blurred vision , nausea , lack of sweating, dry mouth and tachycardia . Resveratrol

1736-400: Is used for the treatment of fungal skin diseases such as ringworm and athlete's foot . As the principal component of gum benzoin , benzoic acid is also a major ingredient in both tincture of benzoin and Friar's balsam. Such products have a long history of use as topical antiseptics and inhalant decongestants . Benzoic acid was used as an expectorant , analgesic , and antiseptic in

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1792-404: Is used to treat diarrhea and some forms of irritable bowel syndrome . Codeine has the strength of 0.1-0.15 compared to morphine ingested orally, hence it is much safer to use. Although codeine can be extracted from the opium poppy, the process is not feasible economically due to the low abundance of pure codeine in the plant. A chemical process of methylation of the much more abundant morphine

1848-403: The antifungal properties of benzoic acid, which was used for a long time in the preservation of benzoate-containing cloudberry fruits . Benzoic acid is produced commercially by partial oxidation of toluene with oxygen . The process is catalyzed by cobalt or manganese naphthenates . The process uses abundant materials, and proceeds in high yield. The first industrial process involved

1904-498: The Fair and Equitable Sharing of Benefits Arising from their Utilization to the Convention on Biological Diversity was signed in 2010. The protocol regulates the conservation and protection of genetic resources to prevent the exploitation of smaller and poorer countries. If genetic, protein or small molecule resources sourced from biodiverse countries become profitable a compensation scheme

1960-592: The absorption of benzoic acid into the cell. If the intracellular pH changes to 5 or lower, the anaerobic fermentation of glucose through phosphofructokinase is decreased by 95%. The efficacy of benzoic acid and benzoate is thus dependent on the pH of the food. Benzoic acid, benzoates and their derivatives are used as preservatives for acidic foods and beverages such as citrus fruit juices ( citric acid ), sparkling drinks ( carbon dioxide ), soft drinks ( phosphoric acid ), pickles ( vinegar ) and other acidified foods. Typical concentrations of benzoic acid as

2016-493: The acetic acid solvent is lost by decomposition or "burning". Product loss by decarboxylation to benzoic acid is common. The high temperature diminishes oxygen solubility in an already oxygen-starved system. Pure oxygen cannot be used in the traditional system due to hazards of flammable organic–O 2 mixtures. Atmospheric air can be used in its place, but once reacted needs to be purified of toxins and ozone depleters such as methylbromide before being released. Additionally,

2072-493: The corresponding diol . These plasticizers, which are used similarly to those derived from terephthalic acid ester, represent alternatives to phthalates . Benzoic acid and its salts are used as food preservatives , represented by the E numbers E210 , E211 , E212 , and E213 . Benzoic acid inhibits the growth of mold , yeast and some bacteria . It is either added directly or created from reactions with its sodium , potassium , or calcium salt. The mechanism starts with

2128-438: The corrosive nature of bromides at high temperatures requires the reaction be run in expensive titanium reactors. The use of carbon dioxide overcomes many of the problems with the original industrial process. Because CO 2 is a better flame inhibitor than N 2 , a CO 2 environment allows for the use of pure oxygen directly, instead of air, with reduced flammability hazards. The solubility of molecular oxygen in solution

2184-447: The early 20th century. In teaching laboratories, benzoic acid is a common standard for calibrating a bomb calorimeter . Benzoic acid occurs naturally as do its esters in many plant and animal species. Appreciable amounts are found in most berries (around 0.05%). Ripe fruits of several Vaccinium species (e.g., cranberry , V. vitis macrocarpon ; bilberry , V. myrtillus ) contain as much as 0.03–0.13% free benzoic acid. Benzoic acid

2240-496: The following. Terephthalic acid can also be made from toluene by the Gattermann-Koch reaction , which gives 4-methylbenzaldehyde . Oxidation of the latter gives terephthalic acid. Terephthalic acid can be prepared in the laboratory by oxidizing many para -disubstituted derivatives of benzene , including caraway oil or a mixture of cymene and cuminol with chromic acid . Although not commercially significant, there

2296-456: The global average due to the social stigma around it. Codeine, also an alkaloid derived from the opium poppy, is considered the most widely used drug in the world according to World Health Organization . It was first isolated in 1832 by a French chemist Pierre Jean Robiquet , also known for the discovery of caffeine and a widely used red dye alizarin . Primarily codeine is used to treat mild pain and relief coughing although in some cases it

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2352-600: The need to isolate intermediates and still using air as the oxidant. Amoco (as Standard Oil of Indiana) purchased the Mid-Century/ICI technology, and the process is now known by their name. In the Amoco process, which is widely adopted worldwide, terephthalic acid is produced by catalytic oxidation of p -xylene : The process uses a cobalt – manganese – bromide catalyst . The bromide source can be sodium bromide , hydrogen bromide or tetrabromoethane . Bromine functions as

2408-480: The presence of toxic cardiac glycosides . The butterflies are not only resistant to the toxins, but are actually able to benefit by actively sequestering them, which can lead to the deterrence of predators. Plants are capable of producing and synthesizing diverse groups of organic compounds and are divided into two major groups: primary and secondary metabolites. Secondary metabolites are metabolic intermediates or products which are not essential to growth and life of

2464-825: The producing plants but rather required for interaction of plants with their environment and produced in response to stress. Their antibiotic, antifungal and antiviral properties protect the plant from pathogens. Some secondary metabolites such as phenylpropanoids protect plants from UV damage. The biological effects of plant secondary metabolites on humans have been known since ancient times. The herb Artemisia annua which contains Artemisinin , has been widely used in Chinese traditional medicine more than two thousand years ago. Plant secondary metabolites are classified by their chemical structure and can be divided into four major classes: terpenes , phenylpropanoids (i.e. phenolics ), polyketides , and alkaloids . Terpenes constitute

2520-485: The production of polybutylene terephthalate and several other engineering polymers . Terephthalic acid is poorly soluble in water and alcohols; consequently, until about 1970 terephthalic acid was purified as its dimethyl ester . It sublimes when heated. Terephthalic acid and its dimethyl ester have very low toxicity , with LD 50 >1 g/kg (oral, mouse). In Comamonas thiooxydans strain E6, terephthalic acid

2576-1083: The prokaryotic cell wall are endotoxins . Examples of bacterial secondary metabolites are: Archaea are capable of producing a variety of secondary metabolites, which may have significant biotechnological applications. Despite knowing this, the biosynthetic pathways for secondary metabolites in archaea are less understood than those in bacteria. Notably, archaea often lack some biosynthesis genes commonly present in bacteria, which suggests that they may possess unique metabolic pathways for synthetizing these compounds. Extracellular polymeric substances can effectively adsorb and degrade hazardous organic chemicals. While these compounds are produced by various organisms, archaea are particularly promising for wastewater treatment due to their high tolerance to saline concentrations and their ability to grow anaerobically. Archaeocins are antibiotic peptides that can be mainly divided in two classes: Halocins and sulfolobicins . Diketopiperazines are cyclic dipeptides with potential for medical and industrial purposes . Selective breeding

2632-436: The reaction of benzotrichloride (trichloromethyl benzene) with calcium hydroxide in water, using iron or iron salts as catalyst . The resulting calcium benzoate is converted to benzoic acid with hydrochloric acid . The product contains significant amounts of chlorinated benzoic acid derivatives. For this reason, benzoic acid for human consumption was obtained by dry distillation of gum benzoin . Food-grade benzoic acid

2688-694: The rye in brine solution with healthy grains sinking and infected floating. Bacterial production of secondary metabolites starts in the stationary phase as a consequence of lack of nutrients or in response to environmental stress. Secondary metabolite synthesis in bacteria is not essential for their growth, however, they allow them to better interact with their ecological niche. The main synthetic pathways of secondary metabolite production in bacteria are; b-lactam, oligosaccharide, shikimate, polyketide and non-ribosomal pathways. Many bacterial secondary metabolites are toxic to mammals . When secreted those poisonous compounds are known as exotoxins whereas those found in

2744-458: The same forest, four separate species of arboreal marsupial folivores reacted differently to a secondary metabolite in eucalypts. This shows that differing types of secondary metabolites can be the split between two herbivore ecological niches. Additionally, certain species evolve to resist secondary metabolites and even use them for their own benefit. For example, monarch butterflies have evolved to be able to eat milkweed ( Asclepias ) despite

2800-511: The way for further oxidation to monomethyl terephthalate. In the Dynamit−Nobel process these two oxidations and the esterification were performed in a single reactor. The reaction conditions also lead to a second esterification, producing dimethyl terephthalate , which could be hydrolysed to terepthalic acid. In 1955, Mid-Century Corporation and ICI announced the bromide- catalysed oxidation of p -toluic acid directly to terephthalic acid, without

2856-399: Was discovered in the sixteenth century. The dry distillation of gum benzoin was first described by Nostradamus (1556), and then by Alexius Pedemontanus (1560) and Blaise de Vigenère (1596). Justus von Liebig and Friedrich Wöhler determined the composition of benzoic acid. These latter also investigated how hippuric acid is related to benzoic acid. In 1875 Salkowski discovered

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2912-454: Was first isolated in 1973 from barks of a coniferous tree, the Pacific Yew . Morphine and codeine both belong to the class of alkaloids and are derived from opium poppies . Morphine was discovered in 1804 by a German pharmacist Friedrich Sertürner t. It was the first active alkaloid extracted from the opium poppy . It is mostly known for its strong analgesic effects, however, morphine

2968-617: Was later awarded the Nobel Prize for the discovery in 2015. Currently, the malaria parasite , Plasmodium falciparum , has become resistant to artemisinin alone and the World Health Organization recommends its use with other antimalarial drugs for a successful therapy. Paclitaxel the active compound found in Taxol is a chemotherapy drug used to treat many forms of cancers including ovarian cancer , breast cancer , lung cancer , Kaposi sarcoma , cervical cancer , and pancreatic cancer . Taxol

3024-488: Was put in place for the countries of origin. Terephthalic acid Terephthalic acid is an organic compound with formula C 6 H 4 (CO 2 H) 2 . This white solid is a commodity chemical , used principally as a precursor to the polyester PET , used to make clothing and plastic bottles . Several million tons are produced annually. The common name is derived from the turpentine -producing tree Pistacia terebinthus and phthalic acid . Terephthalic acid

3080-564: Was used as one of the first biotechnological techniques used to reduce the unwanted secondary metabolites in food, such as naringin causing bitterness in grapefruit. In some cases increasing the content of secondary metabolites in a plant is the desired outcome. Traditionally this was done using in-vitro plant tissue culture techniques which allow for: control of growth conditions, mitigate seasonality of plants or protect them from parasites and harmful-microbes. Synthesis of secondary metabolites can be further enhanced by introducing elicitors into

3136-494: Was vanillin, widely used in the food beverage industry as flavouring. The process involves inserting the desired secondary metabolite gene into an artificial chromosome in the recombinant yeast leading to synthesis of vanillin. Currently Evolva produces a wide array of chemicals such as stevia , resveratrol or nootkatone . With the development of recombinant technologies the Nagoya Protocol on Access to Genetic Resources and

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