Transcription factor mediated control of anthocyanin biosynthesis in plant tissues (2023)

FAQs

What control anthocyanin biosynthesis? ›

The anthocyanin biosynthetic pathway is transcriptionally regulated by a MBW complex. The MYB transcription factors primarily determine the activation or repression role of the MBW complex, by binding to the promoters of structural genes, together with the common bHLH and WD40 factors.

In plants, anthocyanins are controlled by specific factors of the biosynthetic pathway: light, temperature, phytohormones and transcription factors.

The anthocyanin biosynthetic pathway (Figure ​4) is an extension of the general flavonoid pathway, which starts with the chalcone synthase (CHS) mediated synthesis of naringenin chalcone from 4-coumaroyl-CoA and malonyl-CoA. Then, naringenin chalcone is isomerized by chalcone isomerase (CHI) to naringenin.

The synthesis of anthocyanins in plants is controlled by structural genes and can be divided into four stages [21,22]. The early stage is from phenylalanine to 4-coumaryl CoA sequentially catalyzed by phenylalanine ammonialyase (PAL), cinnamate 4-hydroxylase (C4H), and 4-coumarate-CoA ligase (4CL).

However, anthocyanins have a major disadvantage, namely their low stability. Thus, their stability is influenced by a number of factors such as pH, light, temperature, co-pigmentation, sulfites, ascorbic acid, oxygen and enzymes.

The main factors affecting the extraction of anthocyanins from berries and fruit residue are the characteristics of sample matrix (such as water activity of sample, rigidity of plant cell wall, etc.) and extraction process parameters (such as pH, solvent, temperature, time, etc.).

Dihydroflavonol 4-reductase (DFR) is the key enzyme in the anthocyanin biosynthetic pathway. It is responsible for the reduction of flavonol to colorless anthocyanins, which plays an important role in the modification of flower color (Nakatsuka et al., 2005b).

A reaction between sugars and certain proteins in cell sap forms anthocyanins. This reaction does not occur until the sugar concentration in the sap is quite high.

Anthocyanins are a class of flavonoids, which impart different colors to plant parts. Plant tissue culture is an alternative for the production of natural colors to replace synthetic dyes. Anthocyanin possesses excellent antioxidant properties (Szymanowska et al.

Anthocyanins are derived from branches of the flavonoid pathway, which starts with phenylalanine via the general phenylpropanoid pathway. The phenylpropanoid pathway contains three major genes: PAL, C4H and 4CL.

How do you extract anthocyanin from plants? ›

This is the classical method of extracting anthocyanins from plant materials. This procedure involves maceration or soaking of the plant material in methanol containing a small concentration of mineral acid (e.g., HCl). Methanol extraction is a rapid, easy, and efficient method for anthocyanin extraction.

Anthocyanins are flavonoid pigments that accumulate in the large central vacuole of most plants.

Owing to their specific pyrylium nucleus (C-ring), anthocyanins express a much richer chemical reactivity than the other flavonoid classes. For instance, anthocyanins are weak diacids, hard and soft electrophiles, nucleophiles, prone to developing π-stacking interactions, and bind hard metal ions.

The stabilizing methods include additions of copigment compounds, such as polymers, phenolic compounds, and metals.

If plants lacked anthocyanin, no part of the plant would display purple or blue colour. Anthocyanin attracts the insects for pollination and seed dispersal. These processes will be affected due to lack of anthocyanin. These pigments are also said to be protective in nature for the plant.

Retention coefficients of anthocyanin of 0.94 to 0.99 corresponding to percentage recovery between 93 and 99% were obtained.

In fact, the processing can significantly influence anthocyanin content and by consequence the antioxidant capacity of convenience foods formulated from these raw materials. Processes applied to raw materials also affect the behavior of phenols; the analysis of these effects will be useful to optimize processes.

The color of anthocyanins is depending on the pH of the solution. This is because of the molecular structure of anthocyanins having an ionic nature [15]. In acidic condition, some of the anthocyanins appear red. Anthocyanins have a purple hue in neutral pH while the color changes to blue in an increasing pH condition.

The antioxidant mechanisms of the anthocyanins typically include the suppression of reactive species formation, through enzyme inhibition or the sequestration of trace elements involved in the production of free radicals [88].

The enzymes GOGAT and GDH catalyze the nitrogen assimilation reactions. In bacteria, the enzyme glutamate 5-kinase initiates the biosynthesis of proline by transferring a phosphate group from ATP onto glutamate.

What is anthocyanin regulation? ›

The colors regulated by anthocyanins give plants different visual effects through different biosynthetic pathways that provide pigmentation for flowers, fruits and seeds to attract pollinators and seed dispersers.

Other anthocyanin-rich foods include purple corn, pomegranate, eggplant, black carrots, red cabbage, and purple cauliflower, which may provide anywhere from a few to 200–300 mg per 3.5 ounces (100 grams) ( 6 ).

Anthocyanins are induced in plants in response to abiotic stresses such as drought, high salinity, excess light, and cold, where they often correlate with enhanced stress tolerance.

Not all land plants contain anthocyanin; in the Caryophyllales (including cactus, beets, and amaranth), they are replaced by betalains. Anthocyanins and betalains have never been found in the same plant.

Significance of Anthocyanins | Encyclopedia MDPI. Anthocyanins are widespread and biologically active water-soluble phenolic pigments responsible for a wide range of vivid colours, from red (acidic conditions) to purplish blue (basic conditions), present in fruits, vegetables, and coloured grains.

So plants produce anthocyanins specifically when light intensity is high, but temperatures are low enough to slow photosynthesis. They produce anthocyanins to protect themselves against the damaging effects of collecting more energy than they can use.

They are probably the most important group of visible plant pigments besides chlorophyll. Apart from imparting color to plants, anthocyanins also have an array of health-promoting benefits, as they can protect against a variety of oxidants through a various number of mechanisms.

Acetone, methanol, and ethanol were found to be the most efficient in extracting blueberry anthocyanins, whereas trifluoroacetic acid and hydrochloric acid were best suited for solvent acidification. Among these three solvents, ethanol is the least toxic.

Among these extraction methods, the most applied techniques to extract anthocyanins are: ultrasound-assisted extraction (UAE), microwave-assisted extraction (MAE), supercritical fluid extraction (SFE), high-pressure liquid extraction (HPLE), pulsed electric fields (PEFE), high voltage electrical discharge (HVED), and ...

What is the formula for anthocyanin extraction? ›

The supernatant was then removed, and the absorbance was read at 520 and 700 nm, and anthocyanin was calculated by formula (2). where A = (A₅₂₀ nm − A₇₀₀ nm) pH 1.0 − (A₅₂₀ nm − A₇₀₀ nm) pH 4.5; V = volume of extract (ml) and M = mass of the sample (g).

Cytokinins enhance anthocyanin content and transcript levels of sugar inducible structural gene UDPglucose: flavonoid 3-O-glucosyl transferase and regulatory gene PRODUCTION OF ANTHOCYANIN PIGMENT 1.

Anthocyanins are colored water-soluble pigments belonging to the phenolic group. The pigments are in glycosylated forms. Anthocyanins responsible for the colors, red, purple, and blue, are in fruits and vegetables. Berries, currants, grapes, and some tropical fruits have high anthocyanins content.

Anthocyanins are derived from branches of the flavonoid pathway, which starts with phenylalanine via the general phenylpropanoid pathway. The phenylpropanoid pathway contains three major genes: PAL, C4H and 4CL.

Considering the law that “like dissolves like”, the solvents commonly used to extract anthocyanins are: methanol, ethanol, water, acetone, or mixtures thereof. Acid solutions are often added to these solvents to help stabilize the flavylium cation, which is stable in highly acidic conditions (pH ~ 3).

Under the pH conditions prevailing in plants, food and in the digestive tract (from pH = 2 to pH = 8), anthocyanins change to a mixture of colored and colorless forms in equilibrium through acid–base, water addition–elimination, and isomerization reactions [1,2].

Anthocyanins have been described as compounds that prevent or inhibit, the oxidation by scavenging free radicals and reducing the oxidative stress. On a regular basis, anthocyanins act as H-atom donator or as single electron transfer.

Plants rich in anthocyanins are Vaccinium species, such as blueberry, cranberry, and bilberry; Rubus berries, including black raspberry, red raspberry, and blackberry; blackcurrant, cherry, eggplant (aubergine) peel, black rice, ube, Okinawan sweet potato, Concord grape, muscadine grape, red cabbage, and violet petals.

Anthocyanins become unstable under different environmental conditions, mainly pH, temperature, light, and oxygen, factors which are critical for the effective control of their extraction, processing or storage. All three practices may involve the use of heat.

Anthocyanins absorb light in the blue-green wavelengths, allowing the red wavelengths to be scattered by the plant tissues to make these organs visible to us as red.