Objective: To find a natural plant essential oil (EO) with excellent antimicrobial effect on food-borne bacteria and to explore the mechanism of its antimicrobial function against Escherichia colt (E. cal). Methods: T...Objective: To find a natural plant essential oil (EO) with excellent antimicrobial effect on food-borne bacteria and to explore the mechanism of its antimicrobial function against Escherichia colt (E. cal). Methods: The antimicrobial activity of seven EOs against Gramnegative E. coli ATCC 8739 and Gram-positive Staphylococcus aureus ATCC 6538 was investigated using agar disk diffusion method, and the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of each EO was determined using the broth dilution method. The chemical composition of the Trachyspermum copticum (T. copticum) EO was analyzed using gas chromatography mass spectrometry (GC/MS). In order to explore the mechanism of the antimicrobial action, 1 MIC and 2 MIC of T. copticum. EO was added to a suspension of E. coli, the growth curve and the scanning electron microscopy (SEM) analysis of E. coli, and the release of cell constituents and protein and potassium ions from the bacterial cell were measured. Results: The T. optician EO had the best antimicrobial activity against the test bacteria, and 10 compounds accounting for 94.57% of the total oil were identified, with the major components being thymol (46.22%), p-cymene (19.03%), and y-terpinene (22.41%). The addition of I MIC T. copticum. EO significantly inhibited the growth of E. coli and increased the release of cell constituents and protein and potassium ions from the bacterial cells. Scanning electron micrographs showed that T. copticum EO caused most of the E. co/i cell membranes to collapse and rupture, leading to cell death. Conclusions: These results indicate that T. copticum EO is a good natural antimicrobial agent for food-borne pathogens.展开更多
This survey was conducted to evaluate the impact of virgin olive oil nanoemulsion(ONE) combined with ajowan(Carum copticum) essential oil(AEO) on quality of lamb loin under refrigerated condition. The treatments were ...This survey was conducted to evaluate the impact of virgin olive oil nanoemulsion(ONE) combined with ajowan(Carum copticum) essential oil(AEO) on quality of lamb loin under refrigerated condition. The treatments were control, ONE, ONE + 1% AEO, and ONE + 2% AEO. The treatments caused a delay in growth of mesophilic and psychrotrophic bacteria, Enterobacteriaceae, and lactic acid bacteria during chilled storage. The increasing rate of total volatile nitrogen content, lipid and protein oxidation, metmyoglobin formation, and color deterioration was more retarded in treatment groups. The treatments including ONE + 1% AEO and ONE + 2% AEO were more efficient than ONE alone to delay microbial flora growth, slow down oxidative processes, and improve color in the loins. According to the results of microbial, chemical, and sensory parameters, shelflife of lamb loins was 4 days in control, 8 days in ONE, and at least 16 days in ONE + 1% AEO and ONE + 2% AEO groups. In conclusion, combination of ONE and AEO is appropriate as natural preservative to extend the shelflife of lamb loins stored under chilled condition.展开更多
Microwave-assisted rapid extracellular biosynthesis of silver nanoparticles was carried out by using carom seed (Trachyspermum copticum) extract as the reducing agent. The reaction mixture containing AgNO3 and carom s...Microwave-assisted rapid extracellular biosynthesis of silver nanoparticles was carried out by using carom seed (Trachyspermum copticum) extract as the reducing agent. The reaction mixture containing AgNO3 and carom seed extract when exposed to microwave irradiation resulted in reducing silver ions to bio-functionalized silver nanoparticles of size 6- 50 nm. The AgNP were characterized by UV-vis spectroscopy (UV-vis), X-ray diffraction (XRD), energy dispersive X-ray analysis (EDAX), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and atomic force microscopy (AFM). Themogravimetric analysis (TGA) and fourier transform infrared spectroscopy (FTIR) are used to understand the possible mechanism of biosynthesis. In this study, we have also investigated the antimicrobial and antioxidant activities of bio-functionalized AgNP. The antibacterial activity is investigated by measuring the zone of inhibition and antioxidant study is done using 1,1-diphenyl-2-picryl hydrazyl (DPPH) method.展开更多
Plant secondary metabolites play an important role in plant-insect interactions and therefore such compounds may have insecticidal or antifeedant activity against insects. Carum copticum C. B. Clarke （Apiaceae） is o...Plant secondary metabolites play an important role in plant-insect interactions and therefore such compounds may have insecticidal or antifeedant activity against insects. Carum copticum C. B. Clarke （Apiaceae） is one of these plants that have medicinal effects on humans. The chemical composition of the essential oil from dry seeds of C. copticum was studied by gas chromatography （GC） and gas chromatography mass spectrometry （GC-MS）. Thymol （41.34%）,α-terpinolene （17.46%） and ρ-cymene （11.76%） were found to be the major constituents of the oil. In fumigant toxicity tests with the essential oil against adults of Sitophilus oryzae （L.） and Tribolium castaneum （Herbst） at 27 ±1℃ and 60% ± 5% RH, it was observed that S. oryzae （LC50 = 0.91 μL/L） were significantly susceptible than T. castaneum （LC50 = 33.14 μL/L）. The mortalities of the insect species reached 100% at concentrations higher than 185.2 μL/L and 12-h exposure time. The findings indicate the strong insecticidal activity of C. copticum oil and its potential role as a fumigant for storedproduct insects.展开更多
基金supported by the ‘13th Five-Year’ scientific research and innovation team of Tianjin University of Science&Technology(green food packaging and intelligent packaging)the ‘12th Five-Year’ National Science and Technology Support Project of People's Republic of China(Grant No.2015BAD16B05-02)
文摘Objective: To find a natural plant essential oil (EO) with excellent antimicrobial effect on food-borne bacteria and to explore the mechanism of its antimicrobial function against Escherichia colt (E. cal). Methods: The antimicrobial activity of seven EOs against Gramnegative E. coli ATCC 8739 and Gram-positive Staphylococcus aureus ATCC 6538 was investigated using agar disk diffusion method, and the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of each EO was determined using the broth dilution method. The chemical composition of the Trachyspermum copticum (T. copticum) EO was analyzed using gas chromatography mass spectrometry (GC/MS). In order to explore the mechanism of the antimicrobial action, 1 MIC and 2 MIC of T. copticum. EO was added to a suspension of E. coli, the growth curve and the scanning electron microscopy (SEM) analysis of E. coli, and the release of cell constituents and protein and potassium ions from the bacterial cell were measured. Results: The T. optician EO had the best antimicrobial activity against the test bacteria, and 10 compounds accounting for 94.57% of the total oil were identified, with the major components being thymol (46.22%), p-cymene (19.03%), and y-terpinene (22.41%). The addition of I MIC T. copticum. EO significantly inhibited the growth of E. coli and increased the release of cell constituents and protein and potassium ions from the bacterial cells. Scanning electron micrographs showed that T. copticum EO caused most of the E. co/i cell membranes to collapse and rupture, leading to cell death. Conclusions: These results indicate that T. copticum EO is a good natural antimicrobial agent for food-borne pathogens.
基金a part of MSc dissertation approved and financially supported by the Shahrekord University, Iran。
文摘This survey was conducted to evaluate the impact of virgin olive oil nanoemulsion(ONE) combined with ajowan(Carum copticum) essential oil(AEO) on quality of lamb loin under refrigerated condition. The treatments were control, ONE, ONE + 1% AEO, and ONE + 2% AEO. The treatments caused a delay in growth of mesophilic and psychrotrophic bacteria, Enterobacteriaceae, and lactic acid bacteria during chilled storage. The increasing rate of total volatile nitrogen content, lipid and protein oxidation, metmyoglobin formation, and color deterioration was more retarded in treatment groups. The treatments including ONE + 1% AEO and ONE + 2% AEO were more efficient than ONE alone to delay microbial flora growth, slow down oxidative processes, and improve color in the loins. According to the results of microbial, chemical, and sensory parameters, shelflife of lamb loins was 4 days in control, 8 days in ONE, and at least 16 days in ONE + 1% AEO and ONE + 2% AEO groups. In conclusion, combination of ONE and AEO is appropriate as natural preservative to extend the shelflife of lamb loins stored under chilled condition.
文摘Microwave-assisted rapid extracellular biosynthesis of silver nanoparticles was carried out by using carom seed (Trachyspermum copticum) extract as the reducing agent. The reaction mixture containing AgNO3 and carom seed extract when exposed to microwave irradiation resulted in reducing silver ions to bio-functionalized silver nanoparticles of size 6- 50 nm. The AgNP were characterized by UV-vis spectroscopy (UV-vis), X-ray diffraction (XRD), energy dispersive X-ray analysis (EDAX), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and atomic force microscopy (AFM). Themogravimetric analysis (TGA) and fourier transform infrared spectroscopy (FTIR) are used to understand the possible mechanism of biosynthesis. In this study, we have also investigated the antimicrobial and antioxidant activities of bio-functionalized AgNP. The antibacterial activity is investigated by measuring the zone of inhibition and antioxidant study is done using 1,1-diphenyl-2-picryl hydrazyl (DPPH) method.
文摘Plant secondary metabolites play an important role in plant-insect interactions and therefore such compounds may have insecticidal or antifeedant activity against insects. Carum copticum C. B. Clarke （Apiaceae） is one of these plants that have medicinal effects on humans. The chemical composition of the essential oil from dry seeds of C. copticum was studied by gas chromatography （GC） and gas chromatography mass spectrometry （GC-MS）. Thymol （41.34%）,α-terpinolene （17.46%） and ρ-cymene （11.76%） were found to be the major constituents of the oil. In fumigant toxicity tests with the essential oil against adults of Sitophilus oryzae （L.） and Tribolium castaneum （Herbst） at 27 ±1℃ and 60% ± 5% RH, it was observed that S. oryzae （LC50 = 0.91 μL/L） were significantly susceptible than T. castaneum （LC50 = 33.14 μL/L）. The mortalities of the insect species reached 100% at concentrations higher than 185.2 μL/L and 12-h exposure time. The findings indicate the strong insecticidal activity of C. copticum oil and its potential role as a fumigant for storedproduct insects.
