Antioxidant Activity and Bioactive Compounds of Lamium album Flower Extracts Obtained by Supercritical Fluid Extraction

Abstract

In this research, supercritical CO2 extraction is applied to extract bioactive compounds from Lamium album (white dead nettle, Lamiaceae). Extraction was performed at various temperatures (40, 50, and 60 °C) using methanol as co-solvent at a constant flow rate of CO2, methanol, and pressure. The collected extracts were characterized in terms of antioxidant capacity by using DPPH, ABTS and FRAP in vitro antioxidant activity assays, whereas the Folin–Ciocalteu procedure was employed to estimate the total phenols content (TPC). On the other hand, phenolic compounds in the extracts were quantitated by liquid chromatography coupled with a photodiode array detector (UPLC-PDA) and confirmed with a mass detector (TQD). The extracts have shown high TPC ranged between 234.17 to 650.17 mg GAE/g extract. DPPH scavenging of the extracts was estimated and obtained EC50 values ranged from 0.12 to 0.37 mg/mL of solution. The ABTS radical scavenging activity ranged from 43.20 to 44.53 µg TE/g. The FRAP value was found within the range of 19.48 to 44.74 µmol TE/g of extract. Differences between extraction conditions were observed. In this research, 50 °C/250 bar was efficient for the TPC, DPPH, ABTS, and FRAP assays; moreover, statistically, TPCs and FRAP assay showed significant differences between the conditions at α = 0.05. The identification of phenolic compounds in the obtained extract of Lamium album flowers, using UPLC/PDA, revealed that chrysin, pinostrobin, myricetin, and trans-3-hydroxycinnamic acid were the significant molecules present, which may be responsible for the high content of polyphenols and antioxidant activity. The results obtained indicated that SC-CO2 could be considered an alternative method for extracting bioactive compounds of Lamium album. High antioxidant activity and the presence of various bioactive compounds indicate the potential of this plant from the Lamiaceae family and the possibility of its application in various industries, including agriculture, food technology, or pharmacy.

An Overview of Bioactive Flavonoids from Citrus Fruits

“…On this basis, finding various extraction strategies to overcome this difficulty becomes a critical step to improve extraction efficiency and/or selectivity. Or, using dedicated aids/energy-intensive intrants, such as microwave-assisted extraction [50], pressurized liquid extraction [51], supercritical fluid extraction [52], ultrasound-assisted extraction, cold plasma-assisted extraction [53], high pressure assisted extraction [54], pulsed electric field assisted extraction [55], and enzyme-assisted extraction [56], is well documented in the scientific literature as an efficient alternative. In general, while studying plant-derived chemicals, the method and solvents utilized for extraction must be carefully adopted [57].…”

Extraction of natural bioactive compounds using clean label technologies and their application as muscle food preservatives

“…Additionally, the study reported that the SCE improved the yield of bioactive compounds when compared with other extraction techniques (Pimentel-Moral et al, 2019). Similarly, methanol was used as a co-solvent for SCE extraction of bioactive compounds from Lamium album flower (Uwineza et al, 2021). The results indicated that the obtained extract had high antioxidant properties (estimated using FRAP, ABTS, and DPPH assays) and the presence of co-solvent had significantly influenced the phenolic content in the extract (Uwineza et al, 2021).…”

“…Similarly, methanol was used as a co-solvent for SCE extraction of bioactive compounds from Lamium album flower (Uwineza et al, 2021). The results indicated that the obtained extract had high antioxidant properties (estimated using FRAP, ABTS, and DPPH assays) and the presence of co-solvent had significantly influenced the phenolic content in the extract (Uwineza et al, 2021). Besides this, SCE also reported for the extraction of other biomolecules such as lipids (especially polyunsaturated fatty acids and omega-6 fatty acids), proteins, from the cells of microalgae (Sarkar et al, 2022).…”

“…MAE has reported both stances as complete elimination and reduction of solvent requirement for extraction. Hence it can be clearly suggested MAE as a technique that can reduce or eliminate the need for organic solvents in the extraction process, leading to benefits in terms of safety, environmental impact, and cost (Klimek et al, 2021;Uwineza et al, 2021;Sarkar et al, 2022).…”

Clitoria ternatea Flower and Its Bioactive Compounds: Potential Use as Microencapsulated Ingredient for Functional Foods

“…Food industries nowadays are interested in finding natural food additives, such as colorants and preservatives, that are stable to develop and have functional derivative products [6][7][8]. C. ternatea can be a great source of natural food additives due to its bioactive compounds, especially anthocyanin.…”