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排序方式: 共有1036条查询结果,搜索用时 15 毫秒
1.
We have assessed the antimicrobial, vapor-phase activity of the following natural essential oils (EOs) when used in paraffin-based “active coatings” for paper packaging materials intended to come into contact with foods: clove (Sygzium aromaticum), cinnamon (Cinnamomum zeylanicum), and oregano (Origanum vulgare) EOs, and cinnamaldehyde-enriched cinnamon EO. To our knowledge, this is the first time that such an approach has been presented for consideration by the scientific community. 相似文献
2.
以过硫酸铵、亚硫酸氢钠作为引发剂,N,N’-亚甲基双丙烯酰胺作为交联剂,将木薯淀粉与丙烯酸、辣椒碱在水溶液中接枝共聚,合成了具有抗菌性的高吸水性树脂。文章主要考察了添加辣椒碱形式、反应温度、反应时间、引发剂用量、丙烯酸中和度、交联剂用量对合成产物吸水性能的影响。 相似文献
3.
Maritza F. Díaz José A. Gavín Magali Gómez Vicente Curtielles Frank Hernández 《臭氧:科学与工程》2006,28(1):59-63
Prior studies have proven that ozonated vegetable oils present a high germicidal power. Ozonation of sunflower oil at different applied ozone dosage was carried out and peroxide and aldehydes indices along with antimicrobial activity were determined. The reaction products were identified using Proton Nuclear Magnetic Resonance Spectroscopy (1H NMR). The principal signals intensity values were used for following the reaction course between ozone and sunflower oil. The reaction was following up to peroxide index values of 1202 mmol-equi/kg. The intensities of olefinic proton signals decreased with the gradual increase in ozone concentration but without disappearing completely. The Criegee ozonides obtained at 107.1 mg/g of ozone doses were approximately 3.9-fold higher than that at beginning of the reaction. The aldehyde protons were observed as a weak intensity signal in all the spectra. The signals belonging to olefinic protons from hydroperoxides appeared weak and increased with the increase in ozone doses. Signals from other oxygenated groups were assigned. The highest action spectrum of antimicrobial activity was obtained with the higher peroxide index. It was concluded that at higher applied ozone doses, the higher the antimicrobial activity potential of ozonized sunflower oil 相似文献
4.
本论文以水杨醛为主要原料,经发烟硝酸硝化合成5-硝基水杨醛,再分别与对氟苯胺、邻甲苯胺、邻氯苯胺及均三嗪的衍生物作用,合成了四种席夫碱,其中与对氟苯胺、邻甲苯胺、均三嗪的衍生物作用合成而得的席夫碱未见报道。对所合成的四种席夫碱进行生物活性测试,结果表明,该四种席夫碱对供试菌种(大肠杆菌、假丝酵母菌、毛霉菌、鼠伤寒沙门氏菌)都有一定的抑制作用,对细菌的抑制作用强于对霉菌的抑制作用,且浓度愈高抑菌作用愈强。对氟苯胺席夫碱抑菌效果最为特出,是一种潜在的抑菌剂,可进一步深入研究。 相似文献
5.
《Food Control》2014
Escherichia coli O157:H7 and Salmonella spp. often contaminate fresh beef. In Japan, an E coli outbreak caused by raw beef made 181 people ill and 5 individuals dead in 2011. Responding to this outbreak, an effective sterilization method for fresh beef is expected to be developed. In this study, ε-polylysine combined with CO2-packaging method was examined for controlling these pathogens in fresh beef. At an incubation temperature of 4 °C, approximately 4.3 log and 2.4 log reduction in bacterial numbers were observed after 7-day incubation for E. coli O157:H7 and Salmonella, respectively, in ε-polylysine-added beef. When effectiveness of CO2-packaging combined with ε-polylysine was investigated, CO2 did not have additional inhibiting effect on bacterial growth compared to only-ε-polylysine-treated samples when incubated at 4 °C. However, effectiveness of CO2 was observed when incubated at 10 °C where approximately 2.9 log and 4.4 log reduction in E. coli cell numbers were observed in only-ε-polylysine-treated samples and polylysine- and CO2-treated group, respectively, and approximately 1.7 log and 3.5 log reduction in Salmonella cell numbers were observed in only-ε-polylysine-treated samples and polylysine and CO2-treated group, respectively. This study confirmed that ε-polylysine or ε-polylysine combined with CO2 packaging are effective in preventing foodborne diseases caused by raw beef. 相似文献
6.
Alejandra Cardelle-Cobas Patrícia J. M. Reis Eduardo Costa Manuela E. Pintado 《国际聚合物材料杂志》2019,68(9):481-488
Chitosan-impregnated gutta-percha points (ChitGPP) were tested for their ability to inhibit the growth of microorganisms usually involved in root canal infections. Their mechanical properties were also studied and compared with the commonly used commercial points in endodontics. ChitGPP were more efficient in reducing the microbial load than those without chitosan. ChitGPP also possess better tensile and elastic properties than commercial ones. After six months of storage, ChitGPP’s were still able to reduce the bacterial load by 1 log, suggesting that impregnation of gutta-percha points with chitosan could be a good alternative to obtain gutta-percha points with improved antimicrobial properties. 相似文献
7.
Antifungal activity of five different essential oils in vapour phase for the control of Colletotrichum gloeosporioides and Lasiodiplodia theobromae in vitro and on mango
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Anand Babu Perumal Periyar Selvam Sellamuthu Reshma B. Nambiar Emmanuel Rotimi Sadiku 《International Journal of Food Science & Technology》2016,51(2):411-418
Mango fruit has high commercial value; however, major postharvest losses are encountered throughout the supply chain due to postharvest diseases. These results lead to the search for natural fungicide for postharvest diseases control. The antifungal effects of five essential oils (thyme, clove, cinnamon, anise and vitex) were assessed by disc volatilisation method. Thyme oil vapours at 5 μL per Petriplate, and clove and cinnamon oil at 8 μL per Petriplate showed 100% growth inhibition of mango pathogens in vitro. GC/MS analysis of essential oil showed thymol (23.88), o‐cymol (23.88) and terpinolene (23.88) as the major constituents of thyme oil. Clove and cinnamon oils contain 3‐allyl‐2‐methoxyphenol (37.42%) and benzofuran 3‐methyl (17.97%), respectively. Thyme oil as a fumigant at 66.7 μL L?1 showed a significant (P < 0.05) inhibition on postharvest pathogens of mango fruits stored at 25 °C for 6 days. Results of our study suggest the possibility of using thyme oil as an alternate natural fungicide to manage postharvest diseases in mango. 相似文献
8.
《Ceramics International》2017,43(4):3706-3712
Silver phosphate is a promising photocatalyst since its energy band gap is situated in the visible range (Eg≈2.4 eV), thus this material is a potential candidate for replacing titania which is photoactive only under UV. However, Ag3PO4 suffers of photocorrosion and therefore composites should be prepared to limit this detrimental effect. In this work, pure Ag3PO4 and its composites with AgI, TiO2, and hydroxyapatite were prepared by using various methods. The photoactivity of the materials was evaluated by their ability to decolorize methylene blue and to mineralize phenol under non-filtered and UV-filtered artificial solar-like radiation. The use of UV cut-off filter enhanced the photocatalytic activity of pure silver phosphate by limiting the photocorrosion of silver(I) into Ag°. For composites with AgI and TiO2, despite their lower photoactivity compared to pure Ag3PO4, the efficiency in mineralization of phenol after repeated run is stabilized by using UV cut-off filter. On the other hand, the photocatalytic efficiency of Ag3PO4 composites containing hydroxyapatite remained low mainly due to high absorption properties of hydroxyapatite. The photoactive samples showed excellent photoinduced antimicrobial properties where Gram-negative E. coli was more susceptible to photocatalytic deactivation than Gram-positive S. aureus (MRSA). 相似文献
9.
A. Zomorodian I. A. Ribeiro J. C. S. Fernandes A. C. Matos C. Santos A. F. Bettencourt 《国际聚合物材料杂志》2017,66(11):533-543
Magnesium and magnesium alloys are attracting considerable interest as biodegradable materials with high potential for application as temporary implants. The high corrosion rate of Mg-based implants is considered a serious drawback, and it is crucial to design novel surface protection strategies that minimize the detrimental effects of corrosion, while contributing for introducing additional functionalities on the material surface. In this work, a layer-by-layer coating architecture composed of an inner poly(lactic-co-glycolic) acid layer, working as adhesion promoter, and additional polycaprolactone (PCL) layers working as reservoirs for antibiotic (levofloxacin) and for nanohydroxyapatite (nanoHA) particles was applied on the Mg alloy AZ31. The results demonstrate that the composition and number of PCL layers can tailor the biodegradation of the bare magnesium alloy, surface wettability, and the kinetics of release of antibiotic (levofloxacin). The distribution of nanoHA in the coating architecture plays a crucial role on tailoring the desired biocompatible functionalities and corrosion protection of the bare alloy. 相似文献
10.
Commiphora myrrha (Nees) Engl. extracts: evaluation of antioxidant and antiproliferative activity and their ability to reduce microbial growth on fresh‐cut salad
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Luisa Boffa Arianna Binello Valentina Boscaro Margherita Gallicchio Gabriella Amisano Stefania Fornasero Giancarlo Cravotto 《International Journal of Food Science & Technology》2016,51(3):625-632
With the aim to develop natural preservatives displaying also chemopreventive activity, different Commiphora myrrha (Nees) Engl. extracts were studied. Myrrh essential oils, obtained by steam distillation and microwave‐assisted hydrodistillation, and several other extracts, obtained by sequential procedures with petroleum ether (PE), ethanol, ethyl acetate and butanol, have been screened for their antioxidant (DPPH· scavenging assay) and antiproliferative activity (on both nontumour and colon cancer cell lines) without previous purification. Considering that the colon cancer cell lines were more sensitive to PE and ethanol extracts, the latter of which showed the highest antioxidant activity (EC50 = 0.160 ± 0.008 mg mL?1), both have been selected for further antibacterial/antifungal activity tests using an antimicrobial diffusion test and a growth inhibition test on salads. Results showed that the ethanol extract possessed the higher antibacterial and antifungal activity. Compared to untreated product, fresh‐cut salads treated with these two myrrh extracts displayed a significant lower bacterial growth. Although further investigation is required, these promising results offer hints as how to improve the shelf life of fresh‐cut salad. 相似文献