Insights into the physiology, biochemistry and ecological significance of the red seaweed Tricleocarpa fragilis in the Andaman Sea

Abstract

The present study focused on the physiological and biochemical aspects of Tricleocarpa fragilis, red seaweed belonging to the phylum Rhodophyta, along the South Andaman coast, with particular attention given to its symbiotic relationships with associated flora and fauna. The physicochemical parameters of the seawater at the sampling station, such as its temperature, pH, and salinity, were meticulously analyzed to determine the optimal harvesting period for T. fragilis. Seaweeds attach to rocks, dead corals, and shells in shallow areas exposed to moderate wave action because of its habitat preferences. Temporal variations in biomass production were estimated, revealing the highest peak in March, which was correlated with optimal seawater conditions, including a temperature of 34 ± 1.1 °C, a pH of 8 ± 0.1, and a salinity of 32 ± 0.8 psu. GC‒MS analysis revealed n-hexadecanoic acid as the dominant compound among the 36 peaks, with major bioactive compounds identified as fatty acids, diterpenes, phenolic compounds, and hydrocarbons. This research not only enhances our understanding of ecological dynamics but also provides valuable insights into the intricate biochemical processes of T. fragilis. The established antimicrobial potential and characterization of bioactive compounds from T. fragilis lay a foundation for possible applications in the pharmaceutical industry and other industries.

Keywords: Andaman Sea; Antimicrobial compounds; Biomass dynamics; Pharmaceutical applications; Physiological ecology; Seaweed biochemistry.

Fig. 1

Sampling stations along the coast of South Andaman

Fig. 2

Tricleocarpa fragilis from the study area

Fig. 3

Thallus of Tricleocarpa fragilis

Fig. 4

Cortex layer of T. fragilis

Fig. 5

Tricleocarpa fragilis growing on rocky substrata

Fig. 6

Biomass production of T. fragilis during Dec. 2016–Dec. 2017

Fig. 7

Physicochemical parameters of seawater at the sampling station during Dec. 2016–Dec. 2017

Fig. 8

Correlations between environmental attributes and T. fragilis biomass during Dec. 2016–Dec. 2017

Fig. 9

Associated flora and fauna of T. fragilis

Fig. 10

Percentage composition of different phyla associated with T. fragilis

Fig. 11

Antibacterial activity and inhibition zones of the purified fractions of T. fragilis

Fig. 12

GC‒MS chromatogram of the F4 fraction