• Preventive Nutrition and Food Science
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• v.19 no.3
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• pp.129-135
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• 2014

The protective role of phloroglucinol against oxidative stress and stress-induced premature senescence (SIPS) was investigated in vitro and in cell culture. Phloroglucinol had strong and concentration-dependent radical scavenging effects against nitric oxide (NO), superoxide anions ($O_2{^-}$), and hydroxyl radicals. In this study, free radical generators were used to induce oxidative stress in LLC-PK1 renal epithelial cells. Treatment with phloroglucinol attenuated the oxidative stress induced by peroxyl radicals, NO, $O_2{^-}$, and peroxynitrite. Phloroglucinol also increased cell viability and decreased lipid peroxidation in a concentration-dependent manner. WI-38 human diploid fibroblast cells were used to investigate the protective effect of phloroglucinol against hydrogen peroxide ($H_2O_2$)-induced SIPS. Phloroglucinol treatment attenuated $H_2O_2$-induced SIPS by increasing cell viability and inhibited lipid peroxidation, suggesting that treatment with phloroglucinol should delay the aging process. The present study supports the promising role of phloroglucinol as an antioxidative agent against free radical-induced oxidative stress and SIPS.

• Fisheries and Aquatic Sciences
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• v.16 no.4
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• pp.229-235
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• 2013

In an effort to develop biopolymer-based antioxidant and antibacterial materials, a chitosan-phloroglucinol conjugate was prepared and cellular antioxidant activity and minimum inhibitory concentration against foodborne pathogens and methicillin-resistant Staphylococcus aureus (MRSA) evaluated. The chitosan-phloroglucinol conjugate showed higher antioxidant activities than the unmodified chitosan (P < 0.05). The chitosan-phloroglucinol conjugate showed 62.29% reactive oxygen species scavenging activity, 56.11% lipid peroxidation inhibition activity, and 2.21-fold increase of glutathione expression in mouse macrophage cells. Additionally, the chitosan-phloroglucinol conjugate exhibited higher antibacterial activities than the unmodified chitosan, and the chitosan-phloroglucinol conjugate showed fourfold higher antibacterial activities against MRSA and clinical isolates and twofold higher activities against foodborne pathogens compared to the unmodified chitosan.

• Biomolecules & Therapeutics
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• v.29 no.1
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• pp.90-97
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• 2021

Ultraviolet B (UVB) radiation causes DNA base modifications. One of these changes leads to the generation of 8-oxoguanine (8-oxoG) due to oxidative stress. In human skin, this modification may induce sunburn, inflammation, and aging and may ultimately result in cancer. We investigated whether phloroglucinol (1,3,5-trihydroxybenzene), by enhancing the expression and activity of 8-oxoG DNA glycosylase 1 (Ogg1), had an effect on the capacity of UVB-exposed human HaCaT keratinocytes to repair oxidative DNA damage. Here, the effects of phloroglucinol were investigated using a luciferase activity assay, reverse transcription-polymerase chain reactions, western blot analysis, and a chromatin immunoprecipitation assay. Phloroglucinol restored Ogg1 activity and decreased the formation of 8-oxoG in UVB-exposed cells. Moreover, phloroglucinol increased Ogg1 transcription and protein expression, counteracting the UVB-induced reduction in Ogg1 levels. Phloroglucinol also enhanced the nuclear translocation of nuclear factor erythroid 2-related factor 2 (Nrf2) as well as Nrf2 binding to an antioxidant response element located in the Ogg1 gene promoter. UVB exposure inhibited the phosphorylation of protein kinase B (PKB or Akt) and extracellular signal-regulated kinase (Erk), two major enzymes involved in cell protection against oxidative stress, regulating the activity of Nrf2. Akt and Erk phosphorylation was restored by phloroglucinol in the UVB-exposed keratinocytes. These results indicated that phloroglucinol attenuated UVB-induced 8-oxoG formation in keratinocytes via an Akt/Erk-dependent, Nrf2/Ogg1-mediated signaling pathway.

• Environmental Mutagens and Carcinogens
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• v.25 no.4
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• pp.129-133
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• 2005

We investigated the cytoprotective effect of phloroglucinol, which was isolated from Ecklonia cava (brown seaweed), against oxidative stress induced cell damage in Chinese hamster lung fibroblast(V79-4) cells. Phloroglucinol was found to scavenge intracellular reactive oxygen species (ROS) generated by $\gamma-ray$ radiation. In addition, Phloroglucinol inhibited cell damage induced by radiation through scavenging ROS. Phloroglucinol increased the superoxide dismutase and glutathione peroxidase activity, Taken together, the results suggest that phloroglucinol protectes V79-4 cells against oxidative damage by enhancing the cellular antioxidant enzymes activity.

• Journal of Life Science
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• v.31 no.8
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• pp.729-735
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• 2021

Type 2 diabetes occurs when there is an abnormality in the tissue's ability to absorb glucose. Glucose uptake and metabolism by insulin are the basic mechanisms that maintain blood sugar. Glucose uptake goes through various signaling steps initiated by the binding of insulin to receptors on the cell surface. In line with the foregoing, the purpose of this study was to investigate the effect of 2,7-phloroglucinol-6,6-bieckol (PHB), an active compound isolated from Ecklonia cava, on glucose uptake in 3T3-L1 adipocytes. Notably, PHB increased glucose uptake in a dose-dependent manner owing to the enhanced glucose transporter type 4 (GLUT4) expression in the plasma membrane of 3T3-L1 adipocytes. These effects of PHB were attributed to the phosphorylation of insulin receptor substrate-1 and protein kinase B (PKB or AKT), as well as to the phosphoinositide 3-kinase (PI3K) activation in the insulin signaling pathway. PHB also stimulated 5' AMP-activated protein kinase (AMPK) phosphorylation and activation. The phosphorylation and activation of the PI3K/AKT and AMPK pathways by PHB were identified using wortmannin (a PI3K inhibitor) and compound C (an AMPK inhibitor). In this study, we showed that PHB can increase glucose uptake in 3T3-L1 adipocytes by promoting GLUT4 translocation to the plasma membrane via the PI3K and AMPK pathways. The results indicate that PHB may help improve insulin sensitivity.

• Biomolecules & Therapeutics
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• v.20 no.2
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• pp.158-164
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• 2012

Inhibiting the bioactivities of circulating endothelial progenitor cells (EPCs) results in significant inhibition of neovessel formation during tumor angiogenesis. To investigate the potential effect of phloroglucinol as an EPC inhibitor, we performed several in vitro functional assays using $CD34^+$ cells isolated from human umbilical cord blood (HUCB). Although a high treatment dose of phloroglucinol did not show any cell toxicity, it specifically induced the cell death of EPCs under serum free conditions through apoptosis. In the EPC colony-forming assay (EPC-CFA), we observed a significant decreased in the small EPC-CFUs for the phloroglucinol group, implying that phloroglucinol inhibited the early stage of EPC commitment. In addition, in the in vitro expansion assay using $CD34^+$ cells, treatment with phloroglucinol was shown to inhibit endothelial lineage commitment, as demonstrated by the decrease in endothelial surface markers of EPCs including $CD34^+$, $CD34^+/CD133^+$, $CD34^+/CD31^+$ and $CD34^+/CXCR4^+$. This is the first report to demonstrate that phloroglucinol can inhibit the functional bioactivities of EPCs, indicating that phloroglucinol may be used as an EPC inhibitor in the development of biosafe anti-tumor drugs that target tumor angiogenesis.

• Journal of Marine Bioscience and Biotechnology
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• v.2 no.3
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• pp.187-191
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• 2007

The radical scavenging activity of methanol extracts of seaweeds and their active compounds, alginic acid, fucoidan and phloroglucinol, were investigated under in vitro. Among methanol extracts of seaweeds (sea mustard, sea tangle, seaweed papulosa, fusiforme, sea lettuce, purple laver and chlorella), seaweed papulosa and sea tangle showed strong scavenging activities of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and hydroxyl radical (${\cdot}OH$). In addition, under in vitro, the scavenging activities on DPPH radical of alginic acid and fucoidan, which are active compounds of brown algae, and phloroglucinol, the active compound from Ecklonia species, were evaluated and compared. Fucoidan and phloroglucinol showed strong DPPH scavenging effect, in particular, phloroglucinol had strongest activity among the active compounds. On the other hand, alginic acid did not exert DPPH scavenging activity. From the present study, we could confirm the antioxidative activity of seaweeds and its active compounds.

• Journal of the East Asian Society of Dietary Life
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• v.5 no.1
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• pp.87-93
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• 1995

The oxidized mixture of lipid(methyl linoleate) and phenolics(phloroglucinol) at 37$^{\circ}C$, 82$m\ell$ O/min., for 9 days were separated each by C cartridge and silica cartridge making use of different eluting solvent. And the oxidation products were analyzed by HPLC. In conclusion, the oxidized mixture were separated into methyl linoleate and phloroglucinol by cartridge on HPLC. and also in this experiment, separated methyl linoleate and phloroglucinol could be analyzed in the common eluant, water and acetonitrile on HPLC. SEP-PAK cartridges were used almost sample purification until now, but under the various eluting solvents and conditions, cartridge will be expected to mini columns which can separate different polarity materials.

• Natural Product Sciences
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• v.3 no.1
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• pp.1-7
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• 1997

Eucalyptus is a rich source of biologically active compounds. Among these, phloroglucinol compounds such as sideroxylonals, macrocarpals, euglobals, and robustadials are unique to Eucalyptus species. Sideroxylonal A is a very potent attachment-inhibitor. Macrocarpals show very strong antibacterial activity against gram positive bacteria. Macrocarpals also show HIV-RTase inhibitory activity. Euglobals are potent inhibitors of Epstein-Barr virus activation and are developed as skin and antitumor agents. They also show granulation inhibitory activity. In this review we aim to remove the existing confusion in literature on macrocarpals and discuss the biological activities and structure-activity relationships of phloroglucinol compounds.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.3
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• pp.448-452
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• 2000

실험동물에서 곰피로부터 분리한 phlorglucinol은 acetaminophen의 투여로 현저히 증가된 간조직에 있어서 지질과선화의 함량을 억제하였다. Acetaminophen 투여에 따른 간 cytochrome P-450, aminopyrine N-deme-thylase 및 aniline hydroxylase 활성변동은 관찰할 수 없었다. 곰피 성분 투여군은 glutathione S-transferase의 활성에서는 대조군의 수준에는 미치지 않으나 효소의 활성이 acetaminophen 단독 투여군보다 현저히 증가되었다. 그리고 간조직중 glutathione의 함량은 phlorglucionl을 전처리군에서 acetaminophen 단독 투여군보다 증가되었다. Glutathione reductase 활성에서는 acetaminophen 투여군은 대조군보다 활성이 감소되었으며, 성분으로 전처리한 군은 acetaminophen 단독 투여군보다 증가 되었다. 따라서 곰피에서 분리한 페놀성화합물인 phloroglucinol은 acetaminophen 투여로 증가되던 지질과 산화함량을 감소시키며, acetaminophen 대사효소활성에서는 glutathione S-transferase의 활성이 증가되어 acetaminophen 의 대사를 촉진시키는 것으로 추정된다.