Demonstration of Allium sativum Extract Inhibitory Effect on Biodeteriogenic Microbial Strain Growth, Biofilm Development, and Enzymatic and Organic Acid Production

Abstract

To the best of our knowledge, this is the first study demonstrating the efficiency of Allium sativum hydro-alcoholic extract (ASE) againstFigure growth, biofilm development, and soluble factor production of more than 200 biodeteriogenic microbial strains isolated from cultural heritage objects and buildings. The plant extract composition and antioxidant activities were determined spectrophotometrically and by HPLC–MS. The bioevaluation consisted of the qualitative (adapted diffusion method) and the quantitative evaluation of the inhibitory effect on planktonic growth (microdilution method), biofilm formation (violet crystal microtiter method), and production of microbial enzymes and organic acids. The garlic extract efficiency was correlated with microbial strain taxonomy and isolation source (the fungal strains isolated from paintings and paper and bacteria from wood, paper, and textiles were the most susceptible). The garlic extract contained thiosulfinate (307.66 ± 0.043 µM/g), flavonoids (64.33 ± 7.69 µg QE/g), and polyphenols (0.95 ± 0.011 mg GAE/g) as major compounds and demonstrated the highest efficiency against the Aspergillus versicolor (MIC 3.12–6.25 mg/mL), A. ochraceus (MIC: 3.12 mg/mL), Penicillium expansum (MIC 6.25–12.5 mg/mL), and A. niger (MIC 3.12–50 mg/mL) strains. The extract inhibited the adherence capacity (IIBG% 95.08–44.62%) and the production of cellulase, organic acids, and esterase. This eco-friendly solution shows promising potential for the conservation and safeguarding of tangible cultural heritage, successfully combating the biodeteriogenic microorganisms without undesirable side effects for the natural ecosystems.

Byproducts (Flour, Meals, and Groats) from the Vegetable Oil Industry as a Potential Source of Antioxidants

“…The extracts were obtained by the ultrasound-assisted extraction method involving frequencies ranging from 20 kHz to 2000 kHz for 1h at room temperature. Then, the extracts were centrifuged for 10 min at 10,000 rpm to remove the secondary materials [25].…”

Eco-Friendly Solution Based on Rosmarinus officinalis Hydro-Alcoholic Extract to Prevent Biodeterioration of Cultural Heritage Objects and Buildings

“…Most of these have focused on the development of biocides based on EOs [ 36 , 37 ] and less on hydro-alcoholic plant extracts. Even so, it has been proven that various extracts derived from plants such as A. sativum [ 21 ], Clinopodium nepeta [ 38 ] or Robinia pseudoacacia [ 39 ] can be efficient for treating different cultural heritage objects.…”

“…An adapted diffusion method using 10 μL of hydro-alcoholic extract (50:50; 100 mg/mL) was performed on Potato Dextrose Agar medium inoculated with standard fungal cell suspensions (1 McFarland) belonging to A. niger , A. flavus , A. pseudoglaucus , A. nidulans , A. flavus oryzae , A. versicolor , A. montevidensis , A. clavatus , P. chrysogenum , P. corylophylum , P. expansum , P. digitatum , P. brevicompactum , P. namylowskii , Rhizopus oryzae , A. alternata , F. proliferatum , M. circinelloides , P. lilacinum and on Mueller Hinton (MH) for the bacterial strains, (0.5 McFarland) belonging to B. subtilis , B. megaterium , B. thuringiensis , B. cereus , B. pumilus , B. atrophaeus , A. aurascens , A. globiformis , and P. koreensis, previously isolated from the cultural heritage churches and museum collections of three different geographic locations in Romania [ 19 , 20 , 21 ]. After 5–7 days of incubation at room temperature/24 h at 37 °C the growth inhibition diameters were measured and converted in arbitrary units as previously described [ 21 ].…”

“…In Romania there are very few and scarce studies [ 20 , 21 ] regarding the antimicrobial activity of plant extracts against deteriogenic microorganisms of tangible cultural heritage. This study will address this knowledge gap and will present the in vitro antimicrobial activity of an eco-friendly strategy based on R. officinalis plant extract, against deteriogenic fungal and bacterial strains.…”

Evaluation of the Putative Duplicity Effect of Novel Nutraceuticals Using Physico-Chemical and Biological In Vitro Models

“…The extracts were obtained using the ultrasound-assisted extraction method involving frequencies ranging from 20 kHz to 2000 kHz for 30 min at room temperature. Then, the extracts were centrifuged for 10 min at 10,000× g rpm [ 14 ], filtered through a 0.45 µm porosity cellulose filter, and stored in the freezer until analysis…”