In vitro evaluation of new functional properties of poly-γ-glutamic acid produced by Bacillus subtilis D7

Abstract

We investigated the functionality of poly-γ-glutamic acid (γ-PGA), which is produced by Bacillus subtilis D7, for its potential applications in medicine and cosmetics. The γ-PGA had angiotensin-converting enzyme (ACE) inhibition activity. ACE inhibition activity was dependent on the γ-PGA concentration; the highest ACE inhibition activity was observed at 1.25 mg/l of γ-PGA. IC50 (0.108 mg/ml) of the γ-PGA was lower than that of standard ACE inhibitory drug, N-[(S)-mercapto-2-methylpropionyl]-L-proline (0.247 mg/ml). The γ-PGA also had water-holding capacity and hygroscopicity. Furthermore, the γ-PGA inhibited growth of some pathogenic bacteria, including Listeria monocytogenes, Salmonella typhimurium, Staphylococcus aureus, Klebsiella pneumonia and Esherichia coli. The γ-PGA exhibited a good metal adsorption capacity; Cr (VI) adsorption capacity of γ-PGA increased with decreasing pH, and the maximal adsorption was observed at pH 2. Our results suggest that γ-PGA may be expected to be widely applied in cosmetics, biomedical and environmental industries with the feature of being less harmful to humans and the environment.

Preparation of γ-PGA hydrogels and swelling behaviors in salt solutions with different ionic valence numbers

“…52 This phenomenon can be explained by the chemical structure of g-PGA hydrogels which contained a vast amount of -COOH in the polymeric network. 55 As a result, g-PGA hydrogels were more ion-sensitive and presented more limited swelling Fig. 2 The effect of temperature on the swelling behavior of g-PGA hydrogels.…”

A novel approach to improve poly-γ-glutamic acid production by NADPH Regeneration in Bacillus licheniformis WX-02

“…Poly-γ-glutamic acid (γ-PGA) is a multifunctional biopolymer consisting of D- and L-glutamate as monomers. Due to its features of cation chelating, hygroscopicity, water-solubility, non-toxicity and biodegradability, γ-PGA has been applied in cosmetics, medicine, food, water treatment, and agricultural industries, such as material and drug carrier, food preservative, metal ion chelating agents and highly water absorbable hydrogels 1 2 3 .…”

Preparation, Performances, and Mechanisms of Microbial Flocculants for Wastewater Treatment

“…[129], Bacillus sp. [16,[130][131][132][133][134][135], and Rhodococcus erythropolis [136][137][138].…”