Morphological Diversity of Gracilaria blodgettii Harvey 1853 (Gracilariaceae, Rhodophyta) from Sarawak, Malaysian Borneo

Abstract

Gracilaria red algae are notable for their economic importance as agrophytes, sold as salad vegetable, and used as the base for selected food and nonalcoholic beverages. A wild population of Gracilaria exists in coastal areas of Sarawak, Malaysian Borneo, but there is only limited knowledge on species diversity and its abundance leaving the untapped economic potential of this resource. This study was carried out to determine diversity of wild Gracilaria populations in Lawas, Santubong, and Asajaya, Sarawak, using the combination of morphological character examination and 5′ region of the mitochondrial cytochrome c oxidase 1 (CO1-5P) gene analysis. Identification of the species using morphological characters revealed three species, namely, Gracilaria changii, G. blodgettii, and G. arcuata, had been collected from the sampling sites. However, based on 672 bp CO1-5P gene sequence analysis, all the three species were identified as G. blodgettii; besides, low genetic divergence values (0.17%–0.34%) were scored between samples in this study with the same species in GenBank. In the phylogenetic trees, all samples in this study group together with other G. blodgettii have high bootstrap values; thus, this species is monophyletic. This study implies that species identification of Gracilaria and other seagrass taxa which have a phenotypic plasticity problem should include the CO1-5P gene analysis as it is a reliable gene marker for species diversity assessment.

Molecular identification of Gracilaria species (Gracilariales, Rhodophyta) obtained from the South Coast of Java Island, Indonesia

“…The misidentification of three Gracilaria species in Malaysia i.e. G. blodgettii, G. arcuata, and G. changii, was observed by Hassan et al 2019. Molecular identification based on 672 bp CO1-5P gene sequence analysis indicated those three Gracilaria species need to be identified as one, namely Gracilaria blodgettii (Harvey 1853).…”

“…Identification is commonly based on morphological features. This process has some limitations that lead to the species misidentification due to their high phenotypic plasticity (Hassan et al 2019). Correct identification is crucial for biodiversity studies, while misidentification influences the faults in determining biodiversity.…”

Antioxidant Potential of Physicochemically Characterized Gracilaria blodgettii Sulfated Polysaccharides

“…Red algae, the profuse and primordial marine macrophytes [ 16 ], comprises one of the largest phyla of algae. It belongs to the genus Gracilaria , and it evidently shows its importance in the form of agrophytes by abundantly occupying vegetable market shelves as salad and serves as an imperative ingredient in the production of nonalcoholic drinks and certain foods [ 17 ]. It can grow and reproduce in a vast habitat extending from the Arctic Ocean to the Northern Hemisphere’s tropical seas, where Southeast Asia is located [ 18 ].…”

“…It can grow and reproduce in a vast habitat extending from the Arctic Ocean to the Northern Hemisphere’s tropical seas, where Southeast Asia is located [ 18 ]. Given its easy accessibility, the genus Gracilaria is important to industries as the main source of agar, and it is also consumed locally as an everyday food with great demand [ 17 ]. In addition, it also has the potential to be used in the manufacturing of functional foods and nutraceuticals [ 19 , 20 ], which is a vibrant revenue-making industrial segment [ 21 ].…”

Identification of Gracilariaceae (Rhodophyta) of central Portugal by histological and genetic methods

“…Molecular methods have been used to solve taxonomic and identification problems of seaweeds, including red algae (Hassan et al 2019). Gene markers that have been used to identify Gracilaria are the 5′ region of cytochrome oxidase subunit I (COI-5P) (Ferrer et al 2019;Saunders 2005), the plastid-encoded large subunit of ribulose-1,5-biphosphate carboxylase (rbcL) (Gurgel et al 2018), the intergenic spacer between the cytochrome oxidase subunits 2 and 3 (cox2-3 spacer) (Yow et al 2013), the internal transcribed spacers (ITS) (Destombe et al 2010) and the COI-5P which presents high interspecific variability, helping to identify red seaweeds at species level (Ferrer et al 2019).…”