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The tannin compounds are widely distributed in many species of plants, where they play a role in protection from predation (acting as pesticides) and might help in regulating plant growth. [1] The astringency from the tannins is what causes the dry and puckery feeling in the mouth following the consumption of unripened fruit, red wine or tea. [ 2 ]
Tannins are then released into the vacuole and stored inside as tannin accretions. They are responsible for synthesizing and producing condensed tannins and polyphenols . Tannosomes condense tannins in chlorophyllous organs, providing defenses against herbivores and pathogens, and protection against UV radiation.
The most abundant polyphenols are the condensed tannins, found in virtually all families of plants. Larger polyphenols are often concentrated in leaf tissue, the epidermis, bark layers, flowers and fruits but also play important roles in the decomposition of forest litter, and nutrient cycles in forest ecology.
Tannic acid can be applied to woods low in tannin so chemical stains that require tannin content will react. The presence of tannins in the bark of redwood (Sequoia) is a strong natural defense against wildfire, decomposition and infestation by certain insects such as termites. It is found in the seeds, bark, cones, and heartwood.
Phytochemicals are chemicals of plant origin. [1] Phytochemicals (from Greek phyto, meaning "plant") are chemicals produced by plants through primary or secondary metabolism. [2] [3] They generally have biological activity in the plant host and play a role in plant growth or defense against competitors, pathogens, or predators. [2]
There are a variety of crystal types and shapes that can be stored within an idioblast. Crystals form in plants when there is an excess of minerals available and play various roles in plant function. Druses are crystalline clusters that appear scale or box like and play structural roles in sclerenchymatous idioblasts.
The tannin causes the hide to become supple, less affected by water and more resistant to bacterial attack. [141] At least 120 drugs come from plant sources, many of them from the bark of trees. [142] Quinine originates from the cinchona tree and was for a long time the remedy of choice for the treatment of malaria. [143]
In addition, a number of non-metal salt substances can be used to assist with the molecular bonding of natural dyes to natural fibres—either on their own, or in combination with metal salt mordants—including tannin from oak galls and a range of other plants/plant parts, "pseudo-tannins", such as plant-derived oxalic acid, and ammonia from ...