Medicinal value
Seaweeds offer a wide range of therapeutic possibilities both internally
and externally. The medicinal value of seaweed depends on the
type and particular species. There are several types of seaweed both
wild and cultivated (106) , this means seaweeds can be classified by its
use such as medicine, fertilizer and industrial raw materials (105).
Utilization of seaweeds as medicine date back to 13,000 years ago in
Chile at late Pleistocene settlement (107). Also, there was more
archaeological evidence as to the inclusion of seaweed in folk medicine
for thousands of years ago in Japan, China, Egypt and India (108).
Between 1977 and 1987, the newly discovered chemicals from seaweeds were
35%, followed by sponges 27% and cnidarians 22%.(108). Since then,
there is an increasing trend of discovering pharmacologically active
compounds from seaweed. This indicates that marine organisms can be
utilized as a source of variety compounds with pharmacological
activities including anticancer, antimicrobial, antifungal, antiviral
and anti-inflammatory which are potential sources of new therapeutic
agents (109).
Yi, et al. (2001) (110) investigated the extract from 23 species of
marine algae belonging to the Chlorophyta, Phaeophyta, and Rhodophyta,
using different solvents such as ethanol, acetone, and methanol-toluene.
The results indicated that ethanol extract had the strongest antifungal
activity, while the methanol-toluene extract had the weakest, indicating
the possibility of using ethanol extract as antifungal agent. Similarly,
Khanzada et al. (2007) (111) tested several fractions of an ethanolic
extract of Solieria robusta (Rhodophyta) for antifungal activity
against five fruit rotting fungi isolated from fruits in Pakistan and
found that all fractions inhibited fungal growth ; ethanol had the
highest inhibition ratios, followed by aqueous fraction. On the other
hand, Saidani, et al. (2012) investigated antifungal action of four
species of marine algae of Bejaia coast and reported that all
experimented extracts displayed antifungal action, the maximum
inhibiting effect was noted for Rhodomela confervoides (red
algae) and Padin apavonica (brown algae), respectively against
Candida albicans and Mucor ramaniannus (112). Furthermore, Indira, et
al. (2013) presented the antifungal property of seaweed Halimeda
tuna against nine fungal strains (Aspergillus niger, Aspergillus
flavus, Alternaria , Candida albicans, Epidermophyton floccossum,
Trichophyton mentagrophytes, Trichophyton rubrum, Pencillium sp. and
Rhizopus sp.) (113). Therefore, there is a need to investigate further
medical applicability of seaweeds present in the WIO in order to explore
its benefits for sustainable ecosystem.