• The Korean Journal of Food And Nutrition
• /
• v.33 no.3
• /
• pp.309-316
• /
• 2020

In this study, we investigated the protective effects of Ulva lactuca methanol extracts against ultraviolet B (UVB)-induced DNA damage in HaCaT cells. First, the contents of general and antioxidative nutrient contents of Ulva lactuca were measured. The moisture, carbohydrate, crude protein, crude fat and ash were 14.01%, 44.80%, 23.19%, 3.10% and 14.90%, respectively. Magnesium that acts as DNA repair enzyme cofactor was the most abundant mineral followed by Ca, P and Fe. The total phenolic and anthocyanoside contents of Ulva lactuca were 2.69 mg/g and 0.13 mg/g, respectively. Cells treated with Ulva lactuca methanol extracts for 24 hours post UVB exposure increased cell viability in a concentration-dependent manner compared to the non-treated control. Also, Ulva lactuca methanol extracts decreased the levels of UVB-induced DNA damage such as cyclobutane pyrimidine dimer and DNA damage response (DDR) proteins such as p-p53 and p21. These results suggest that Ulva lactuca methanol extracts comprising physiological active substances such as Mg, polyphenols and anthocyanosides promote DNA repair by regulating genes related with DDR.

• Environmental Mutagens and Carcinogens
• /
• v.26 no.2
• /
• pp.48-52
• /
• 2006

Our investigation of the seaweed extracts, Ulva lactuca. The biological activities antioxidant, antimicrobial activity, antifungal and haemolytic activity of ethy-ether and ethyl-acetate extracts from the seaweed, Ulva lactuca were investigated. They were separately extracted using ethyl-ether and ethyl-acetate from dried samples at room temperature and freeze dried. Seaweed extracts were found to cause significant free radical scavenging effects on DPPH (1,1-diphenyl-2-picrylhydrazyl). Seaweed extracts had not significant haemolytic activity against human erythrocyte. This extracts exhibited in vitro broad-spectrum antimicrobial activity of gram-negative, gram-positive bacteria and without antifungal activity.

• Biotechnology and Bioprocess Engineering:BBE
• /
• v.9 no.3
• /
• pp.236-238
• /
• 2004

This is the first report on the antitumor and immunostimulating activities of Ulva lactuca. Using the WSM (water-soluble fraction of a methanol extract from Ulva lactuca), a concentration of 140 g/mL was found to inhibit 50% of the human leukemia cell line U937 in growth, while splenocyte growth was stimulated up to a concentration of 100$\mu\textrm{g}$/mL. In addition, NO production by a macrophage cell line (RAW 264.7) and alkaline phosphatase activity in mouse splenocytes were both stimulated with 10$\mu\textrm{g}$/mL of WSM. Dose-dependent patterns were observed on all three cell-lines. Accordingly, the current results indicate that VUlva lactuca may be useful as a natural antitumor and immunostimulating agent.

• ALGAE
• /
• v.34 no.4
• /
• pp.253-266
• /
• 2019

Several species classified to the genus Ulva are primarily responsible for causing green tides all over the world. For almost two decades, green tides have been resulted in numerous ecological problems along the eastern coast of Jeju Island, Korea. In order to characterize the species of Ulva responsible for causing the massive blooms on Jeju Island, we conducted DNA barcoding of tufA and rbcL sequences on 183 specimens of Ulva from eight sites on Jeju Island. The concatenated analysis identified five bloom-forming species: U. australis, U. lactuca, U. laetevirens, U. ohnoi and a novel species, U. pseudo-ohnoi sp. nov. Among them, U. australis, U. lactuca, and U. laetevirens caused to the blooms coming mainly from the substratum. U. ohnoi and U. pseudo-ohnoi sp. nov. were causative the free-floating blooms. Four species, except U. australis, are characterized by marginal teeth. A novel species, U. pseudo-ohnoi sp. nov., is clearly diverged from the U. lactuca, U. laetevirens, and U. ohnoi clade in the concatenated maximum likelihood analysis. Accurate species delimitation will contribute to a management of massive Ulva blooms based on this more comprehensive knowledge.

• Environmental Mutagens and Carcinogens
• /
• v.26 no.3
• /
• pp.89-92
• /
• 2006

To enhance our understanding of immunological stimulating effects through the pathway by which nitric oxide (NO) activity and alkaline phosphatase(ALP) enzyme activity from the marine algae, Ulva lactuca, we have investigated NO activity by using mouse RAW264.7 cell line. And ALP enzyme activity performed by spleen of ICR mouse. The results showed that NO activity of the $H_2O$ fraction is the most effective than activities of other solvent fractions.

• Journal of Life Science
• /
• v.16 no.7 s.80
• /
• pp.1169-1173
• /
• 2006

Extracted fractions of the green seaweed Ulva lactuca were studied to verify the cytotoxicity and immunostimulating activity. The fractions from the ethanol extract of U. lactuca were prepared by the systematic extraction procedure with solvents such as hexane, ethyl ether, methanol, butanol and $H_2O$. The cytotoxic effects of U. lactuca fractions against human leukemia cell line U937, mouse neuroblastoma cell line (NB41A3), human hepatoma cell line (HepG2) and rat glioma cell line (C6) were investigated. Ethyl ether fraction showed the highest cytotoxicity against all four cell lines tested. In addition, $H_2O$ fraction also showed relatively high cytotoxicity. Dose dependent patterns were observed on all four cell lines. The immune-stimulating effects of U. lactuca fractions on rat macrophage cell line (RAW 264.7) were also investigated. All five fractions of U. lactuca extract stimulated NO production with concentration dependant manner. These results suggest that U. lactuca may be a useful candidate for a natural cancer preventing and immune-stimulating agents.

• Journal of Life Science
• /
• v.17 no.1 s.81
• /
• pp.51-55
• /
• 2007

The fractions of Ulva lactuca were studied to verify the antioxidant activities. The fractions from the ethanol extract of U. lactuca were prepared by the systematic extraction procedure with the solvents such as hexane, ethyl ether, ethyl acetate, butanol and $H_2O$. Furthermore, ethyl ether, ethyl acetate and aqueous fractions of U. lactuca were purified using HPLC. The antioxidant activities of purified samples from ethyl ether, ethyl acetate, and aqueous fractions were investigated using 1,1-diphenyl-2-picryl-hydrazil (DPPH). L-ascorbic acid, a positive control showed the highest DPPH radical scavenging activity. In addition, purified sample from aqueous fraction also showed relatively high activity. Purified sample from ethyl acetate fraction showed moderate activity, but purified sample from ethyl ether fraction showed the lowest activity. Dose dependent patterns were observed on all three samples tested. The lipid peroxidation inhibition activities of these three purified samples were also investigated. Purified sample from ethyl ether fraction of U. lactuca showed the highest activity and as strong activity as that of $\alpha-tocopherol$, a positive control. These results suggest that U. lactuca may be a useful candidate for a natural antioxidant agent.

• Journal of Life Science
• /
• v.32 no.5
• /
• pp.340-347
• /
• 2022

The anti-inflammatory and antioxidant activities of the Ulva lactuca Linnaeus extracts were measured. As a result of the MTT assay of the extract, it was found that the cell viabilities were higher than 90% at all concentrations, and the cell promotion rate exceeded 100% at a certain concentration. Therefore, in all subsequent experiments, the highest concentration was set at 500 ㎍/ml. In the nitric oxide (NO) assay, one of the anti-inflammatory experiments, the Ulva lactuca Linnaeus extracts exhibited inhibitory effects of 16%, 19%, and 62% at concentrations of 5, 50, and 500 ㎍/ml, respectively, compared with the LPS-only group. In tumor necrosis factor-α (TNF-α) assay, the extracts showed inhibitory effects of 16%, 17%, and 27% at concentrations of 5, 50, and 500 ㎍/ml, respectively, compared with the LPS-only group. In the interleukin-6 (IL-6) assay, the extracts also showed inhibitory effects of 15% and 28% at concentrations of 50 and 500 ㎍/ml, respectively, compared with the LPS-only group. In the total polyphenol content assay, the extracts exhibited 8.02, 9.90, and 23.8 mg GAE/g at concentrations of 0.3, 3, and 30 mg/ml, respectively. In the ABTS assay, the extracts exhibited scavenging activities of 2.6, 12.6, and 77.3% at concentrations of 0.3, 3, and 30 mg/ml, respectively. Therefore, it is considered that Ulva lactuca Linnaeus extracts can be used as anti-inflammatory and antioxidant substances for the development of functional foods.

• Proceedings of the Korean Society of Life Science Conference
• /
• 2005.09a
• /
• pp.54-54
• /
• 2005

• Proceedings of the Korean Society of Life Science Conference
• /
• 2003.10a
• /
• pp.124-124
• /
• 2003