Inhibitory activity of an extract from a marine bacterium Halomonas sp. HSB07 against the red-tide microalga Gymnodinium sp. (Pyrrophyta)

Marine organisms are recognized as a source of compounds with interesting biological activities. Vibrio neocaledonicus has been reported on for its high effectiveness against corrosion in metals but it has been little studied for its chemical and biological activities. In this study, four compounds were isolated from V. neocaledonicus: indole (1); 1H-indole-3-carboxaldehyde (2); 4-hydroxybenzaldehyde (3) and Cyclo (-Pro-Tyr) (4); using a bioassay-guided method, since in a previous study it was found that the ethyl acetate extract was active on the enzymes acetylcholinesterase (AChE), alpha-glucosidase (AG) and xanthine oxidase (XO). The inhibitory activities of the three compounds against AChE, AG and XO was also evaluated. In addition, the enzymatic inhibitory activity of indole to the toxins from the venom of Bothrops asper was tested. Results showed that indole exhibited strong inhibitory activity to AG (IC50 = 18.65 ± 1.1 μM), to AChE, and XO (51.3% and 44.3% at 50 μg/mL, respectively). 1H-indole-3-carboxaldehyde displayed strong activity to XO (IC50 = 13.36 ± 0.39 μM). 4-hydroxybenzaldehyde showed moderate activity to XO (50.75% at 50 μg/mL) and weak activity to AChE (25.7% at 50 μg/mL). Furthermore, indole showed a significant in vitro inhibition to the coagulant effect induced by 1.0 μg of venom. The findings were supported by molecular docking. This is the first comprehensive report on the chemistry of V. neocaledonicus and the bioactivity of its metabolites.

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Purification and characterization of the protease inhibitor "monastatin" from a marine Alteromonas sp. with reference to inhibition of the protease produced by a bacterium pathogenic to fish

Canadian Journal of Microbiology ◽

10.1139/m85-206 ◽

1985 ◽

Vol 31 (12) ◽

pp. 1089-1094 ◽

Cited By ~ 11

Author(s):

Chiaki Imada ◽

Masachika Maeda ◽

Nobuo Taga

Keyword(s):

Protease Inhibitor ◽

Inhibitory Activity ◽

Marine Bacterium ◽

Polyacrylamide Gel Electrophoresis ◽

Gel Filtration ◽

Ammonium Sulfate Precipitation ◽

Purification And Characterization ◽

Wide Range ◽

Thiol Proteases

A novel protease inhibitor, which we named "monastatin," produced by a marine bacterium was purified using ammonium sulfate precipitation, DEAE-cellulofine column chromatography, and gel filtration through Sephadex G-100. Monastatin was purified to homogeneity, as a single staining band in polyacrylamide gel electrophoresis. Monastatin was a glycoprotein with a molecular weight of about 20 000. It was stable up to 100 °C for a 30-min incubation with loss of 20% of inhibitory activity and also showed stability over a wide range of pH from 2 to 12. Metal ions such as Cu2+ and Fe2+ repressed the inhibitory activity to 0%. Monastatin had an inhibitory activity against thiol proteases such as papain and ficin.

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TEM study of a biofilm on copper corrosion

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100163563 ◽

1996 ◽

Vol 54 ◽

pp. 220-221

Author(s):

W. A. Chiou ◽

N. Kohyama ◽

B. Little ◽

P. Wagner ◽

M. Meshii

Keyword(s):

Marine Bacterium ◽

Culture Medium ◽

Copper Alloys ◽

Pure Copper ◽

Localized Corrosion ◽

Natural Seawater ◽

Copper Corrosion ◽

New Approach ◽

The Past ◽

Copper Tolerant

The corrosion of copper and copper alloys in a marine environment is of great concern because of their widespread use in heat exchangers and steam condensers in which natural seawater is the coolant. It has become increasingly evident that microorganisms play an important role in the corrosion of a number of metals and alloys under a variety of environments. For the past 15 years the use of SEM has proven to be useful in studying biofilms and spatial relationships between bacteria and localized corrosion of metals. Little information, however, has been obtained using TEM capitalizing on its higher spacial resolution and the transmission observation of interfaces. The research presented herein is the first step of this new approach in studying the corrosion with biological influence in pure copper.Commercially produced copper (Cu, 99%) foils of approximately 120 μm thick exposed to a copper-tolerant marine bacterium, Oceanospirillum, and an abiotic culture medium were subsampled (1 cm × 1 cm) for this study along with unexposed control samples.

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Inhibitory effects of bioaccessible anthocyanins and procyanidins from apple, red grape, cinnamon on α-amylase, α-glucosidase and lipase

International Journal for Vitamin and Nutrition Research ◽

10.1024/0300-9831/a000652 ◽

2020 ◽

pp. 1-9

Author(s):

Pınar Ercan ◽

Sedef Nehir El

Keyword(s):

Inhibitory Activity ◽

Digestive Enzymes ◽

Positive Control ◽

Anthocyanin Content ◽

Inhibitory Effects ◽

Total Anthocyanin ◽

Total Anthocyanin Content ◽

Before And After ◽

Red Grape

Abstract. The goals of this study were to determine and evaluate the bioaccessibility of total anthocyanin and procyanidin in apple (Amasya, Malus communis), red grape (Papazkarası, Vitis vinifera) and cinnamon (Cassia, Cinnamomum) using an in vitro static digestion system based on human gastrointestinal physiologically relevant conditions. Also, in vitro inhibitory effects of these foods on lipid (lipase) and carbohydrate digestive enzymes (α-amylase and α-glucosidase) were performed with before and after digested samples using acarbose and methylumbelliferyl oleate (4MUO) as the positive control. While the highest total anthocyanin content was found in red grape (164 ± 2.51 mg/100 g), the highest procyanidin content was found in cinnamon (6432 ± 177.31 mg/100 g) (p < 0.05). The anthocyanin bioaccessibilities were found as 10.2 ± 1%, 8.23 ± 0.64%, and 8.73 ± 0.70% in apple, red grape, and cinnamon, respectively. The procyanidin bioaccessibilities of apple, red grape, and cinnamon were found as 17.57 ± 0.71%, 14.08 ± 0.74% and 18.75 ± 1.49%, respectively. The analyzed apple, red grape and cinnamon showed the inhibitory activity against α-glucosidase (IC50 544 ± 21.94, 445 ± 15.67, 1592 ± 17.58 μg/mL, respectively), α-amylase (IC50 38.4 ± 7.26, 56.1 ± 3.60, 3.54 ± 0.86 μg/mL, respectively), and lipase (IC50 52.7 ± 2.05, 581 ± 54.14, 49.6 ± 2.72 μg/mL), respectively. According to our results apple, red grape and cinnamon have potential to inhibit of lipase, α-amylase and α-glucosidase digestive enzymes.

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