Chemical Composition and Antioxidant, Antimicrobial Activities of the Essential Oils of Thymus marschallianus Will. and Thymus proximus Serg.

Abstract

Due to the economical impacts of spoiled foods and the consumer's concerns over the safety of foods, a lot of attention has been paid to naturally derived compounds. Fresh and dried Thymus species as well as their processed products have been widely used as flavorings since ancient times; however, during the last few decades, they also have become a subject for a search of natural antioxidants and antimicrobial agents. Biological activities of Thymus essential oils depend on their chemical composition, which is determined by the genotype and influenced by environmental conditions. Recent studies have showed that Thymus species have strong antimicrobial and antioxidant activities. To the best of our knowledge, the properties of Thymus species growing wild in the Xinjiang have not been reported before.

Effect of the addition of plant extracts on the microbiota of minimally processed strawberry jam and its physicochemical and sensorial properties

“…In this case, the extract concentrations tested were 0.012, 0.008, 0.006, 0.004, 0.003, 0.002, 0.001 and 0.0005 g/mL. The result shown by the jam at 24 h was 6.06 6 10 8 cfu/mL and with MIC, defined as the minimum inhibitory concentration of extract that causes complete inhibition of visible growth (Jia et al, 2010), would be 0.001 g/mL. If MIC is considered as the concentration that produces a 90% reduction (Ponce et al, 2003), it would Antimicrobial activity of pomegranate extract tested in inoculums of 10 2 cfu/mL, 10 4 cfu/mL and 10 6 cfu/mL.…”

“…The minimum inhibitory concentration (MIC) is defined as the minimum level of natural extract concentration that produces a 90% reduction in the growth (population) of microbial colonies (Ponce, Fritz, Valle, & Roura, 2003) or a complete inhibition of visible growth (Jia et al, 2010). The minimum bactericidal concentration (MBC) is defined as the minimum level of natural extract concentration that produces at least a 99.9% reduction in the growth of microbial or fungal colonies, respectively (Skandamis, Koutsoumanis, Fasseas, & Nychas, 2001).…”

“…The chosen dose for the pomegranate extract was 0.0005 g/mL according to the CMI (Ponce et al, 2003). Using the definition of CMI by Jia et al (2010), the dose would be 0.001 g/mL.…”

Changes in the microbiological and physicochemical quality during storage of osmotically dehydrated strawberry jam stabilized with plant extracts

“…The minimum inhibitory concentration (MIC) is defined as the minimum level of natural extract concentration that produces a 90% reduction in the growth (population) of microbial colonies (Ponce, Fritz, Valle, & Roura, 2003) or a complete inhibition of visible growth (Jia, Ji, Xing, Zhang, Zhu, & Wang, 2010). The minimum fungicidal concentration (MFC) is defined as the minimum level of natural extract concentration that produces at least a 99.9% reduction in the growth of fungal colonies (Ernst, 2005).…”

“…In order to quantify this action with greater precision, the broth dilution technique was then used (Davison & Parish, 1989). The initial jam charge pattern at 24 h was 1.03 6 10 2 cfu/mL and MIC was 0.2 or 0.1 g/mL, as defined by Jia et al (2010) and Ponce et al (2003), respectively. Moreover, MFC was 0.1 g/mL.…”