Role of acemannan and pectic polysaccharides in saline-water stress tolerance of Aloe vera (Aloe barbadensis Miller) plant

Int J Biol Macromol. 2024 May;268(Pt 1):131601. doi: 10.1016/j.ijbiomac.2024.131601. Epub 2024 Apr 16.

Abstract

This study investigates the impact of water and salinity stress on Aloe vera, focusing on the role of Aloe vera polysaccharides in mitigating these stresses. Pectins and acemannan were the most affected polymers. Low soil moisture and high salinity (NaCl 80 mM) increased pectic substances, altering rhamnogalacturonan type I in Aloe vera gel. Aloe vera pectins maintained a consistent 60 % methyl-esterification regardless of conditions. Interestingly, acemannan content rose with salinity, particularly under low moisture, accompanied by 90 to 150 % acetylation increase. These changes improved the functionality of Aloe vera polysaccharides: pectins increased cell wall reinforcement and interactions, while highly acetylated acemannan retained water for sustained plant functions. This study highlights the crucial role of Aloe vera polysaccharides in enhancing plant resilience to water and salinity stress, leading to improved functional properties.

Keywords: Abiotic stress; Acemannan; Aloe vera; Degree of acetylation; Functional properties; Pectins.

MeSH terms

  • Acetylation
  • Aloe* / chemistry
  • Cell Wall / chemistry
  • Cell Wall / drug effects
  • Mannans* / chemistry
  • Pectins* / chemistry
  • Polysaccharides / chemistry
  • Polysaccharides / pharmacology
  • Salinity
  • Salt Tolerance / drug effects
  • Stress, Physiological / drug effects
  • Water / chemistry

Substances

  • acemannan