Successfully reported this slideshow.
We use your LinkedIn profile and activity data to personalize ads and to show you more relevant ads. You can change your ad preferences anytime.

SA

3,298 views

Published on

salicylic acid

Published in: Education
  • Login to see the comments

SA

  1. 1. University of Salahaddin-Erbil College of Science Environmental science department 1 Halala Rahman Qadir M.Sc. Plant physiology 2015
  2. 2. Outline Definition of Salicylic acid Structure of salicylic acid Properties of Salicylic acid Effects of salicylic acid 2
  3. 3. Definition of Salicylic acid 3 Salicylic acid (SA): is a phenolic derivative, distributed in a wide range of plant species. It is a natural product of phenylpropanoid metabolism. Decarboxylation of transcinnamic acid to benzoic acid and its subsequent 2- hydroxylation results to SA. It undergoes metabolism by conjugating with glucose to SA glucoside and an ester.
  4. 4. Properties of SA • An odorless, crystalline solid substance. • Has a sweetish taste. • Used externally for treatment of skin diseases. • It has a remote action after absorption. • Causes marked irritation of gastric mucous membrane. 4
  5. 5. Medical uses • Salicylic acid is known for its ability to ease aches and pains and reduce fevers. • salicylic acid is a key ingredient in many skin-care products for the treatment of seborrhoeic dermatitis, acne, psoriasis, calluses, corns, keratosis pilaris, acanthosis nigricans, ichthyosis, and warts. • SA is used in the production of other pharmaceuticals including 4-aminosalicylic acid, sulpiride, letimide (via Salethamide). 5
  6. 6. SA as a plant hormone • Salicylic acid (SA) is a phenolic phytohormone • Is found in plants with roles in plant growth and development, photosynthesis, transpiration, ion uptake and transport. • SA also induces specific changes in leaf anatomy and chloroplast structure. • SA is involved in endogenous signaling, mediating in plant defense against pathogens. • It plays a role in the resistance to pathogens by inducing the production of pathogenesis-related proteins. • It is involved in the systemic acquired resistance (SAR) in which a pathogenic attack on one part of the plant induces resistance in other parts. • The signal can also move to nearby plants by salicylic acid being converted to the volatile ester, methyl salicylate 6
  7. 7. Effects of Salicylic acid SA has direct involvement in plant growth, thermogenesis, flower induction and uptake of ions. It affects ethylene biosynthesis, stomatal movement and also reverses the effects of ABA on leaf abscission. Enhancement of the level of chlorophyll and carotenoid pigments photosynthetic rate and modifying the activity of some of the important enzymes are other roles assigned to SA. 7
  8. 8. Production • Salicylic acid is biosynthesized from the amino acid phenylalanine. In Arabidopsis thaliana it can also be synthesized via a phenylalanine- independent pathway. 8

×