Optimization of Extraction Conditions for Gracilaria gracilis Extracts and Their Antioxidative Stability as Part of Microfiber Food Coating Additives

Abstract

Incorporation of antioxidant agents in edible films and packages often relies in the usage of essential oils and other concentrated hydrophobic liquids, with reliable increases in antimicrobial and antioxidant activities of the overall composite, but with less desirable synthetic sources and extraction methods. Hydroethanolic extracts of commercially-available red macroalgae Gracilaria gracilis were evaluated for their antioxidant potential and phenolic content, as part of the selection of algal biomass for the enrichment of thermoplastic film coatings. The extracts were obtained through use of solid-liquid extractions, over which yield, DPPH radical reduction capacity, total phenolic content, and FRAP activity assays were measured. Solid-to-liquid ratio, extraction time, and ethanol percentages were selected as independent variables, and response surface methodology (RSM) was then used to estimate the effect of each extraction condition on the tested bioactivities. These extracts were electrospun into polypropylene films and the antioxidant activity of these coatings was measured. Similar bioactivities were measured for both 100% ethanolic and aqueous extracts, revealing high viability in the application of both for antioxidant coating purposes, though activity losses as a result of the electrospinning process were above 60% in all cases.

Exploring the Bioactive Potential of Gracilaria gracilis: An Extraction Optimization Study Using Response Surface Methodology

“…This result suggests G. gracilis may harbor heat-sensitive compounds that are extracted more effectively at colder temperatures [8]. Although TPC-specific data on G. gracilis is limited, Reboleira et al [6] highlighted that by comparing aqueous and ethanolic extracts with similar antioxidant potential, a better yield was obtained using water. This study underscores G. gracilis as a promising source of versatile bioactive compounds.…”

“…Gracilaria species, known for their significance in agar production, have gained attention as a promising source of bioactive compounds with potential applications in the food, feed, and pharmaceutical sectors [6]. Studies have revealed that Gracilaria gracilis, in particular, exhibits noteworthy antioxidant properties and radical scavenging activity.…”

Evaluation of bioprospecting potential of epiphytic Gracilaria edulis harvested from seaweed farm in Seriwe Bay, Lombok, Indonesia

“…The antioxidant potential of G. edulis is similar to that of tropical plants (Mustafa et al 2010). Further optimizing extraction conditions may produce different antioxidant activities (Reboleira et al 2020).…”

“…Indonesia contributes significantly to the global seaweed production, particularly the commercial carrageenan producing seaweeds from the generas Kappaphycus and Eucheuma. West Nusa Tenggara (NTB) regency is among the top seaweed producers, along with East Nusa Tenggara, South Sulawesi, and Central Sulawesi (Rimmer et al 2021). However, currently the Indonesian seaweed industry is also facing various challenges and problems, which have caused a steady decline in recent years.…”

Effect of Alga Gelidium sp. Flour Extract on Lipid Damage Evolution in Heated Fish Muscle System

“…Thus, and according to present results, previous in vitro studies have shown antioxidant properties of water extracts obtained from red macroalgae. Research has concerned red algae species such as Hypnea flagelliformis [38], Gracilaria verrucosa [39], and Gracilaria gracilis [40]. In all cases, the preservative behaviour was explained on the basis of the presence of phenolic compounds, flavonoids, carbohydrates, and alkaloids, which have the ability to neutralise free radicals.…”