• Korean Journal of Fisheries and Aquatic Sciences
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• v.41 no.3
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• pp.188-192
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• 2008

Methyl gallate isolated from bark of the tree Rhus verniciflua Stokes has significant antimicrobial activity against the fish pathogenic bacteria Edwardsiella tarda and Vibrio anguillarum. To evaluate the antimicrobial activity of gallate derivatives, eight alkyl gallates were tested. Ethyl gallate and propyl gallate had the highest activities, with MICs of $15.6-31.3{\mu}g/mL$ against E. tarda. For V. anguillarum, propyl gallate and butyl gallate were highly effective, with MICs of $7.81-31.3{\mu}g/mL$. When used in combination with antibiotics, methyl gallate exhibited synergistic effects with oxytetracycline against E. tarda and with norfloxacin against V. anguillarum. These results suggest that short-chain alkyl gallates can be used as alternatives to antibiotics against the fish pathogenic bacteria.

• Journal of fish pathology
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• v.18 no.3
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• pp.227-237
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• 2005

To obtain antimicrobial compounds against fish pathogenic bacteria from natural products, 80% methanolic extracts from 14 species of medicinal plant were screened for antimicrobial activity against fish pathogenic bacteria, Edwardsiella tarda and Vibrio anguillarum. Among them, Glycyrrhiza glabra, Rhus vemiciflua and Sanguisorba officinalis were effective for growth inhibition of Gram-negative bacteria, both E. tarda YSF and V. anguillarum YSR. Through the activity-guided isolation for R. verniciflua extract that exhibited the highest antimicrobial activity among three extracts, one antimicrobial compound (1) was isolated and identified as methyl-3,4,5-trihydroxybenzoate, or methyl gallate. This compound significantly inhibited the growth of tested strains of both E. tarda and V. anguillarum exhibiting MIC of 1 mg/ml for each strain.

• Natural Product Sciences
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• v.23 no.1
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• pp.5-8
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• 2017

An antimicrobial compound has been isolated from the leaves of Glochidion superbum. The compound was determined as methyl 3, 4, 5-trihydroxybenzoate (methyl gallate), based on ultraviolet (UV), infrared (IR), nuclear magnetic resonance (NMR) and mass spectroscopy (MS) analysis. The isolated compound exhibited potent antimicrobial activity against three clinical isolates of methicillin resistant Staphylococcus aureus (MRSA) by qualitative agar disc diffusion method and quantitative broth dilution method. Agar disc diffusion was done in a dose-dependent manner for each bacterial isolate at disc potencies of 25, 50, 100, and $150{\mu}g/disc$. The zones of inhibition were on average equal to 12.27, 14.20, 15.43, and 24.17 mm respectively. The inhibition zones were compared with that of vancomycin disc at $30{\mu}g$ as a reference standard. The MIC and MBC values were $50{\mu}g/ml$ and $100{\mu}g/ml$ respectively. The results of anti MRSA activity were analyzed using one-way ANOVA with Turkey's HSD and Duncan test. In conclusion, methyl gallate which was isolated from G. superbum showed the inhibition activity against methicillin resistant S. aureus.

• Journal of the Korean Wood Science and Technology
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• v.45 no.3
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• pp.250-257
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• 2017

Eight hydrolyzable tannin compounds, such as gallic acid (1), methyl gallate (2), kurigalin (3), 1,2,3,6-tetra-O-galloyl-${\beta}$-D-(+)-glucose (4), 1,2,3,4,6-penta-O-galloyl-${\beta}$-D-(+)-glucose (5), 6-m-digalloyl-1,2,3,4,6-penta-O-galloyl-${\beta}$-D-(+)-glucose (6), isocorilagin (7), macabarterin (8), were isolated from the EtOAc and $H_2O$ soluble fractions of Katsura tree (Cercidiphyllum japonicum) leaves, wood and bark. Then antioxidative and anti-inflammatory activity were evaluated on the each isolated compound. The antioxidative test was DPPH radical scavenging activity and all of the isolated compounds indicated much higher antioxidative values compare to the controls, BHT and ${\alpha}$-tocopherol. In the anti-inflammatory test measuring nitric oxide (NO) inhibition activity, methyl gallate, 1,2,3,6-tetra-O-galloyl-${\beta}$-D-glucose and 1,2,3,4,6-penta-O-galloyl-${\beta}$-D-glucose inhibited NO production, and especially, methyl gallate showed high inhibition activity. However, the anti-inflammatory activity of the hydrolyzable tannins did not show positive effect. Based on the above results, the hydrolyzable tannins of katsura tree may be used as one of the natural biomass sources that can substitute with the synthetic antioxidant.

• Korean Journal of Food Science and Technology
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• v.35 no.4
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• pp.726-732
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• 2003

The crude extracts from Rhus javanica Linne showed comparatively strong antioxidative activity in test oils. Antioxidative components were isolated and identified by column chromatography, thin layer chromatography, UV, and NMR. These antioxidative components were added to several oils to compare antioxidative activity with several commercial antioxidants, such as BHA, BHT, and tocopherol. After the sixth column chromatography, one fraction (R-18-9-3-2-4-2) was separated from chloroform layer of Rhus javanica Linne. The R-18-9-3-2-4-2 fraction was identified as methyl gallate by $^1H-NMR$ and $^{13}C-NMR$ and confirmed with methyl gallate standard as authentic. The R18-9-3-2-4-2 fraction from chloroform layer of Rhus javanica Linne showed stronger activity than that of the ${\alpha}-,\;{\delta}-tocopherol$, BHT, and BHA at the same concentration.

• Korean Journal of Pharmacognosy
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• v.22 no.1
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• pp.22-25
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• 1991

From the fresh unripe fruits of Paeonia moutan Sim. (Paeoniaceae), paeoniflorin and its acyl congeners, benzoylpaeoniflorin and benzoyloxypaeoniflorin, along with ${\beta}-sitosterol$ and methyl gallate were isolated. All compounds were identified on the basis of spectral data and chemical reactions. However, paeonol was not detected from this plant parts. These results suggested that the chemical components of the unripe fruits were virtually similar to those of root barks.

• Korean Journal of Pharmacognosy
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• v.27 no.3
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• pp.219-223
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• 1996

From the rachis of Cedrela sinensis A. Juss., methyl gallate, quercitrin, bis-(p-hydroxyphenyl)ether, adenosine, isoquercitrin, rutin, (+)-catechin and (-)-epicatechin were isolated and characterized by spectral data.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.spc1
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• pp.251-254
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• 2006

This study was conducted to identify changes of chemical components affected by different drying method and temperature conditions in leaves and stems of peony plant. Drying methods were the dried air heated $(50^{\circ}C)$, far-red ray $(50^{\circ}C)$, room temperature and oven dry $(50^{\circ}C)$. Drying temperature were 40, 50, 60, 70 and $80^{\circ}C$ on far-red ray dryer. Among the drying methods, the contents of components were the highest in far-red drying and normal temperature drying as compared with air heated drying and oven drying. Among the drying temperature conditions, the contents of components were the highest in drying temperature at $40^{\circ}C$ and decreased in high temperature of $70^{\circ}C\;and\;80^{\circ}C$.

• Korean Journal of Pharmacognosy
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• v.24 no.4
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• pp.319-321
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• 1993

A tannin compound has been isolated from the underground part of Rosa rugosa Thunb. and its structure has been established to be methyl gallate $3-O-{\beta}-D-(6'-O-galloyl)-glucopyranoside(1)$ on the basis of chemical and spectroscopic evidences. This compound was the first example in this plant.

• The Korean Journal of Physiology and Pharmacology
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• v.17 no.5
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• pp.441-446
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• 2013

In the present study, the anti-depressant like effect of methyl gallate (MG) isolated from the stem bark of Acer barbinerve was examined in ICR mice. Body weight (BDW) and blood glucose (BDG) levels significantly decreased in the repeated restraint stress (RRS) group (2 h/day for 14 days) compared to the no stress (NS) group. To examine the effect of MG on RS-induced BDW loss and hypoglycemia, MG (10 mg/kg) and the anti-depressant fluoxetine (10 mg/kg) were administered daily for 14 days. Orally administered MG and fluoxetine significantly attenuated the RS-induced BDW loss and hypoglycemia. Interestingly, MG administered mice showed increased BDG levels in the normal and glucose feeding condition. Chronic RS-subjected mice showed immobilized and depressed behaviors. The effect of MG on the depressed behaviors was evaluated using the tail-suspension test (TST) and the forced swimming test (FST). In both tests, RS-induced immobilized behaviors were significantly reversed in MG and fluoxetine administered groups. Taken together, MG significantly attenuated the RS-induced BDW loss, hypoglycemia, and depressed behaviors. Considering that decreased BDG levels (hypoglycemia) can cause depression, MG may exert its anti-depressant like effect by preventing hypoglycemia. Our results suggest that MG isolated from A. barbinerve can exert anti-depressant like effect, and could be used as a new and natural anti-depressant therapy.