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1.
N,N,N-Trimethyl O-(2-hydroxy-3-trimethylammonium propyl) chitosans (TMHTMAPC) with different degrees of O-substitution were synthesized by reacting O-methyl-free N,N,N-trimethyl chitosan (TMC) with 3-chloro-2-hydroxy-propyl trimethyl ammonium chloride (CHPTMAC). The products were characterized by 1H NMR, FTIR and TGA, and investigated for antibacterial activity against Staphylococcus aureus and Escherichia coli under weakly acidic (pH 5.5) and weakly basic (pH 7.2) conditions. TMHTMAPC exhibited enhanced antibacterial activity compared with TMC, and the activity of TMHTMAPC increased with an increase in the degree of substitution. Divalent cations (Ba2+ and Ca2+) strongly reduced the antibacterial activity of chitosan, O-carboxymethyl chitosan and N,N,N-trimethyl-O-carboxymethyl chitosan, but the repression on the antibacterial activity of TMC and TMHTMAPC was weaker. This indicates that the free amino group on chitosan backbone is the main functional group interacting with divalent cations. The existence of 100 mM Na+ slightly reduced the antibacterial activity of both chitosan and its derivatives. 相似文献
2.
Antibacterial activity of quaternary ammonium chitosan containing mono or disaccharide moieties: Preparation and characterization 总被引:1,自引:0,他引:1
Warayuth Sajomsang Pattarapond Gonil Supawan Tantayanon 《International journal of biological macromolecules》2009,44(5):419-427
The 9 quaternary ammonium chitosans containing monosaccharides or disaccharides moieties were successfully synthesized by reductive N-alkylation then quaternized by N-(3-chloro-2-hydroxypropyl) trimethylammonium chloride (Quat-188). The chemical structures of quaternary ammonium chitosan derivatives were characterized by ATR-FTIR and 1H NMR spectroscopy. The degree of N-substitution (DS) and the degree of quaternization (DQ) were determined by 1H NMR spectroscopic method. It was found that the DS was in the range of 12–40% while the DQ was in the range of 90–97%. The results indicated that the O-alkylation was occured in this condition. Moreover, all quaternary ammonium chitosan derivatives were highly water-soluble at acidic, basic, and neutral pH. Minimum inhibitory concentration (MIC) antibacterial studies of these materials were carried out on Escherichia coli (Gram-negative) and Staphylococcus aureus (Gram-positive) bacteria compared to quaternary ammonium N-octyl and N-benzyl chitosan derivatives. The quaternary ammonium mono and disaccharide chitosan derivatives showed very high MIC values which were in the range of 32 to >256 μg/mL against both bacteria. Also it was found that the antibacterial activity decreased with increasing the DS. This was due to the increased hydrophilicity of mono and disaccharide moieties. On the other hand, the low MIC values (8–32 μg/mL) were obviously observed when the DS of quaternary ammonium N-octyl and N-benzyl chitosan derivatives was lower than 18%. The results showed that the presence of hydrophobic moiety such as the N-benzyl group enhanced the antibacterial activity compared to the hydrophilic moiety against both bacteria. 相似文献
3.
《Saudi Journal of Biological Sciences》2022,29(4):2582-2590
Despite the wide range of available antibiotics, food borne bacteria demonstrate a huge spectrum of resistance. The current study aims to use natural components such as essential oils (EOs), chitosan, and nano-chitosan that have very influential antibacterial properties with novel technologies like chitosan solution/film loaded with EOs against multi-drug resistant bacteria. Two strains of Escherichia coli O157:H7 and three strains of Listeria monocytogenes were used to estimate antibiotics resistance. Ten EOs and their mixture, chitosan, nano-chitosan, chitosan plus EO solutions, and biodegradable chitosan film enriched with EOs were tested as antibacterial agents against pathogenic bacterial strains. Results showed that E. coli O157:H7 51,659 and L. monocytogenes 19,116 relatively exhibited considerable resistance to more than one single antibiotic. Turmeric, cumin, pepper black, and marjoram did not show any inhibition zone against L. monocytogenes; Whereas, clove, thyme, cinnamon, and garlic EOs exhibited high antibacterial activity against L. monocytogenes with minimum inhibitory concentration (MIC) of 250–400 μl 100?1 ml and against E. coli O157:H7 with an MIC of 350–500 μl 100?1 ml, respectively. Among combinations, clove, and thyme EOs showed the highest antibacterial activity against E. coli O157:H7 with MIC of 170 μl 100?1 ml, and the combination of cinnamon and clove EOs showed the strongest antibacterial activity against L. monocytogenes with an MIC of 120 μl 100?1 ml. Both chitosan and nano-chitosan showed a promising potential as an antibacterial agent against pathogenic bacteria as their MICs were relatively lower against L. monocytogenes than for E. coli O157:H7. Chitosan combined with each of cinnamon, clove, and thyme oil have a more effective antibacterial activity against L. monocytogenes and E. coli O157:H7 than the mixture of oils alone. Furthermore, the use of either chitosan solution or biodegradable chitosan film loaded with a combination of clove and thyme EOs had the strongest antibacterial activity against L. monocytogenes and E. coli O157:H7. However, chitosan film without EOs did not exhibit an inhibition zone against the tested bacterial strains. 相似文献
4.
Antimicrobial activity of saponin fractions of the leaves of Gymnema sylvestre and Eclipta prostrata
Venkatesan Gopiesh khanna Krishnan Kannabiran 《World journal of microbiology & biotechnology》2008,24(11):2737-2740
The antimicrobial activity of saponin fractions from the leaves of Gymnema sylvestre and Eclipta prostrata was evaluated against pathogenic bacteria and fungi in an in vitro condition. A series of concentrations of crude and pure
saponin fractions were tested for antimicrobial activity by zone of inhibition method. The pure saponin fractions were found
to be more effective against tested bacterial pathogens when compared to crude saponin fractions. The minimum inhibitory concentration
(MIC) exhibited by the pure saponin fraction of G. sylvestre was found to be in the range of 600–1,200 mg/l against bacterial strains and 1,400 mg/l for fungal isolates. In the case
of E. prostrata, the range was 1,000–1,200 mg/l for bacteria and 1,400 mg/l for fungal isolates. The susceptibility of bacterial pathogens
for saponin fractions was in the order of P. aeruginosa, E. coli, S. typhi, K. pneumoniae, P. mirablis, S. aureus and for fungal pathogens A. fumigatus followed by A. niger and A. flavus. Whereas, A. niger was more susceptible to inhibition by E. prostrata saponin fractions, followed by A. flavus and A. fumigatus. The antimicrobial potential of saponin fractions was compared with antibiotics, Chloramphenicol and Amphotericin-B with
respect to bacteria and fungi. The present study suggests that the saponin fractions G. sylvestre and E. prostrata possess significant antibacterial and antifungal activity. Our results further suggest that saponins of G. sylvestre and E. prostrata can be used as a potential fungicide against pathogenic fungi. 相似文献
5.
Lavandin (Lavandula × hybrida) is an evergreen shrub and cultivated worldwide for its essential oil which possesses various biological activities. In this study, the essential oils were isolated from the leaves of ten lavandin populations in western Iran. The hydrodistilled essential oils were analyzed by GC‐FID/MS. Results indicated significant differences (P ≤ 0.05) among the various populations for the main essential oil constituents. The major components from different populations were 1,8‐cineole (31.64 – 47.94%), borneol (17.11 – 26.14%), and camphor (8.41 – 12.68%). In vitro antibacterial activity was evaluated against S. agalactiae, S. aureus, E. coli, and K. pneumoniae. The inhibition zones were in the range of 09.36 mm for S. aureus to 23.30 mm for E. coli. Results indicated that there was a significant correlation between essential oil composition and level of antibacterial efficacy expressed as inhibition zones. 相似文献
6.
Chandrasekaran M. Kannathasan K. Venkatesalu V. Prabhakar K. 《World journal of microbiology & biotechnology》2009,25(1):155-160
The antibacterial activity of aqueous and methanol extracts of leaves/shoots of five salt marsh halophytes and six mangroves
was studied against methicillin resistant, clinical isolates of Staphylococcus aureus. There was a clear comparability between the salt marsh halophytes and mangroves in their antibacterial action. The mangrove
plants possessed higher antibacterial potency than the salt marsh halophytes. The highest activity was recorded with the methanol
extract of Excoecaria agallocha followed by the methanol extracts of Aegiceras corniculatum, Lumnitzera racemosa and Ceriops decandra. The minimum inhibitory concentration (MIC) values ranged from 0.125 to 4 mg/mL and 1 to 16 mg/mL for methanol and aqueous
extracts, respectively. Further separation of active principle from the potent mangrove plant will be useful for the control
of drug resistant strains of S. aureus. 相似文献
7.
Warayuth Sajomsang Uracha Ruktanonchai Pattarapond Gonil Varissaporn Mayen Praneet Opanasopit 《Carbohydrate polymers》2009,78(4):743-752
In this study, three kinds of methylated chitosan containing different aromatic moieties were synthesized by two steps, reductive amination and methylation, respectively. The chemical structures of all methylated derivatives, methylated N-(4-N,N-dimethylaminocinnamyl) chitosan chloride (MDMCMChC), methylated N-(4-N,N-dimethylaminobenzyl) chitosan chloride (MDMBzChC), and methylated N-(4-pyridinylmethyl) chitosan chloride (MPyMeChC) were characterized by ATR–FTIR and 1H NMR spectroscopy. The complexes between the chitosan derivatives and plasmid DNA at different N/P ratios were characterized by gel electrophoresis, dynamic light scattering, and atomic force microscopic techniques. The smallest particle sizes of these complexes were obtained at N/P ratio of 5 and ranged from 95 to 124 nm while the zeta-potentials were in the range of 18–27 mV. Transfection efficiencies of these complexes were investigated by expression of the plasmid DNA encoding green fluorescence protein (pEGFP-C2) on human hepatoma cells (Huh 7 cells) compared to N,N,N-trimethyl chitosan chloride (TMChC). The rank of transfection efficiency was MPyMeChC > MDMBzChC > TMChC > MDMCMChC, respectively. The cytotoxicity of these complexes was also studied by MTT assay where the MPyMeChC complex exhibited less toxicity than other derivatives even at high N/P ratios. Therefore, MPyMeChC demonstrated potential as its safe and efficient gene carrier. 相似文献
8.
Isolation of an Antibacterial Substance from Mahonia fortunei and its Biological Activity against Xanthomonas oryzae pv. oryzicola 总被引:1,自引:0,他引:1
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Gaoqing Yuan Yuanyuan Chen Fangjing Li Rongjin Zhou Qiqin Li Wei Lin Lihong Huang 《Journal of Phytopathology》2017,165(5):289-296
This study aimed to isolate the antibacterial substance from Mahonia fortunei and determine its antibacterial activity against Xanthomonas oryzae pv. oryzicola (Xoc). Bacterial leaf streak of rice, caused by Xoc, is an important rice disease and difficult to control. During a screening of antibacterial plants against plant pathogenic bacteria at an early stage, the extract from M. fortunei was found to have a strong inhibitory effect on Xoc. In this study, the chemical components of M. fortunei stems were extracted using methanol solvent, the antibacterial substance was isolated and purified by liquid–liquid partition and silica gel column chromatography and its structure was identified by nuclear magnetic resonance. The effect and mode of action of the antibacterial substance on bacterial leaf streak of rice were also detected under greenhouse conditions. Two compounds were identified, berberine and jatrorrhizine, which had a strong inhibitory effect on Xoc. The antibacterial activity of berberine was stronger, with a half‐maximal inhibitory concentration (IC50) of 2.9008 mg/l. At the concentration of 0.5 g/l, its control efficacy on bacterial leaf streak of rice was more than 84%. Additionally, berberine could be absorbed by rice leaves and be translocated up and down in the rice plant, and the effective period was long, but its capability of lateral translocation inside the blade was poor. 相似文献
9.
Waraporn Putalun Orapin Udomsin Gorawit Yusakul Thaweesak Juengwatanatrakul Seiichi Sakamoto Hiroyuki Tanaka 《Biotechnology letters》2010,32(5):721-724
Methyl jasmonate, 50 μM, 0.5 mg yeast extract/l and 100 mg chitosan/l stimulated plumbagin production in Drosera burmanii whole plant cultures after 6 days of elicitation. Yeast extract (0.5 mg/l) was the most efficient enhancing plumbagin production
in roots of D. burmanii to 8.8 ± 0.5 mg/g dry wt that was 3.5-fold higher than control plants. 相似文献
10.
Syed Sultan Beevi Lakshmi Narasu Mangamoori Naveen Anabrolu 《World journal of microbiology & biotechnology》2009,25(3):465-473
Aqueous, methanol, ethyl acetate, and chloroform extracts of the root, stem, and leaf of Raphanus sativus were studied for antibacterial activity against food-borne and resistant pathogens. All extracts except the aqueous extracts
had significant broad-spectrum inhibitory activity. The ethyl acetate extract of the root had the potent antibacterial activity,
with a minimum inhibitory concentration (MIC) of 0.016–0.064 mg/ml and a minimum bactericidal concentration (MBC) of 0.016–0.512 mg/ml
against health-damaging bacteria. This was followed by the ethyl acetate extracts of the leaf and stem with MICs of 0.064–0.256
and 0.128–0.256 mg/ml, respectively and MBCs of 0.128–2.05 and 0.256–2.05 mg/ml, respectively. The ethyl acetate extracts
of the different parts of R. sativus retained their antibacterial activity after heat treatment at 100°C for 30 min, and their antibacterial activity was enhanced
when pH was maintained in the acidic range. Hence this study, for the first time, demonstrated that the root, stem, and leaf
of R. sativus had significant bactericidal effects against human pathogenic bacteria, justifying their traditional use as anti-infective
agents in herbal medicines. 相似文献
11.
Kathawut Sopalun Kanchit Thammasiri Keiko Ishikawa 《Plant Cell, Tissue and Organ Culture》2010,101(2):143-150
Protocorm-like bodies (PLBs) were induced from shoot tips of Grammatophyllum speciosum, a Thai orchid. The highest frequency of PLBs (93%) were observed on explants incubated on 1/2-Murashige and Skoog (MS) liquid
medium containing 2% (w/v) sucrose without any plant growth regulators (PGRs). Tests with different carbon sources compared
to sucrose revealed that maltose promoted the highest relative growth of G. speciosum PLBs (7-fold increase), while trehalose and sucrose yielded 5-fold and 4-fold increases, respectively. In 1/2 MS liquid medium,
addition of 15 mg/l of chitosan promoted a 7-fold increase in PLB growth while 25 mg/l promoted a 4-fold increase. However,
the relative growth rate in solid culture was significantly lower than that in liquid culture. In addition, chitosan supplementation
in solid medium promoted shoot formation but not rooting. Plantlet regeneration was induced using a combination of NAA and
BA supplementation in 1/2 MS solid medium with optimum induction shoot and root formation at 2.0 mg/l NAA and 1.0 mg/l BA.
Using this protocol, approximately 8 months was required to obtain a hundred plantlets from one shoot tip. The plantlets showed
no changes in ploidy when tested by flow cytometry. 相似文献
12.
Giuseppina Sandri Maria Cristina Bonferoni Silvia Rossi Franca Ferrari Cinzia Boselli Carla Caramella 《AAPS PharmSciTech》2010,11(1):362-371
The aim of this paper was to evaluate the penetration enhancement properties of nanoparticles (NP) based on N-trimethyl chitosan (TMC 35% quaternization degree) loaded with insulin. The permeation performances of TMC NP were compared
with those of chitosan (CS) NP and also with TMC and CS solutions. To estimate the mechanism of penetration enhancement, two
different approaches have been taken into account: an in vitro study (Caco-2 cells) and an ex vivo study (excised rat duodenum, jejunum, and ileum). Insulin-loaded CS and TMC NP had dimensions of about 250 nm and had high
yield and high encapsulation efficiency. The in vitro study evidenced that TMC and CS were able to enhance insulin permeation to the same extent. Penetration enhancement properties
of TMC NP seem to be prevalently related to endocytosis while the widening of tight junctions appeared more important as mechanism
in the case of CS NP. The ex vivo study put in evidence the role of mucus layer and of its microclimate pH. In duodenum (pH 5–5.5), CS and TMC solutions were
more effective than NP while TMC NP were more efficient towards jejunum tissue (pH 6–6.5) for their high mucoadhesive potential.
Confocal laser scanning microscopy study supported the hypothesis that penetration enhancement due to TMC NP was mainly due
to internalization/endocytosis into duodenum and jejunum epithelial cells. The good penetration enhancement properties (permeation
and penetration/internalization) make TMC NP suitable carriers for oral administration of insulin. 相似文献
13.
Rasanthika Nayomi Jayatissa Rohan Prasantha Perera Chamari Madhu Hettiarachchi Pathum Manjula Weerawarna 《Indian journal of microbiology》2012,52(1):83-87
The continuing increase in the incidence of multi drug resistant pathogenic bacteria and shortage of new antimicrobial agents
are the prime driver in efforts to identify the novel antimicrobial classes. In vitro antibacterial activity of 4-phenyl-1-(2-phenylallyl)
pyridinium bromide was tested against Gram positive Staphylococcus aureus, Streptococcus species, Bacillus subtilis, and Gram negative Klebsiella aerogenes and Escherichia coli using disk diffusion method. Among them S. aureus showed strong antibacterial activity (21.99 ± 0.03 mm) while E. coli showed very little activity (8.97 ± 0.06 mm) towards the compound. The MIC of 4-phenyl-1-(2-phenyl-allyl)-pyridinium bromide
for 90% S. aureus was ≤20 μg/ml and was compared with phenoxymethylpenicillin, cloxacillin, erythromycin and vancomycin. When 4-phenyl-1-(2-phenyl-allyl)pyridinium
bromide showed MIC at ≤20 μg/ml, all others showed MIC at ≤100 μg/ml. Strong antibacterial activity of 4-phenyl-1-(2-phenyl-allyl)pyridinium
bromide against S. aureus indicates that there is a possibility to use it as an effective antibacterial agent. 相似文献
14.
Tocci N Simonetti G D'Auria FD Panella S Palamara AT Valletta A Pasqua G 《Applied microbiology and biotechnology》2011,91(4):977-987
Hypericum perforatum is a well-known medicinal plant which contains a wide variety of metabolites, including xanthones, which have a wide range
of biological properties, including antifungal activity. In the present study, we evaluated the capability of roots regenerated
from calli of H. perforatum subsp. angustifolium to produce xanthones. Root biomass was positively correlated with the indole-3-butyric acid concentration, whereas a concentration
of 1 mg l−1 was the most suitable for the development of roots. High auxin concentrations also inhibited xanthone accumulation. Xanthones
were produced in large amounts, with a very stable trend throughout the culture period. When the roots were treated with chitosan,
the xanthone content dramatically increased, peaking after 7 days. Chitosan also induced a release of these metabolites into
the culture. The maximum accumulation (14.26 ± 0.62 mg g−1 dry weight [DW]) and release (2.64 ± 0.13 mg g−1 DW) of xanthones were recorded 7 days after treatment. The most represented xanthones were isolated, purified, and spectroscopically
characterized. Antifungal activity of the total root extracts was tested against a broad panel of human fungal pathogen strains
(30 Candida species, 12 Cryptococcus neoformans, and 16 dermatophytes); this activity significantly increased when using chitosan. Extracts obtained after 7 days of chitosan
treatment showed high antifungal activity (mean minimum inhibitory concentration of 83.4, 39.1, and 114 μg ml−1 against Candida spp., C. neoformans, and dermatophytes, respectively). Our results suggest that root cultures can be considered as a potential tool for large-scale
production of extracts with stable quantities of xanthones. 相似文献
15.
Purification,Characterization and Antibacterial Activity of l‐amino Acid Oxidase from Cerastes cerastes
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Ziad‐Meziane Hanane‐Fadila Laraba‐Djebari Fatima 《Journal of biochemical and molecular toxicology》2014,28(8):347-354
Antibiotic resistance presents a real problem in which new antibacterial molecules from natural secretions could be beneficial in the development of new drugs. In this study, Cerastes cerastes venom was investigated for its antibacterial activity against Gram‐positive and Gram‐negative bacteria. The antibacterial activity was evaluated by measuring the halo inhibition and minimum inhibitory concentration (MIC). An l ‐amino acid oxidase (CcLAAO) was purified from this venom using three chromatographic steps; its homogeneity (60 kDa) was confirmed by SDS‐PAGE. LC–MS/MS analysis of CcLAAO showed similarities with other LAAO enzymes from Echis ocellatus and Viridovipera stejnegeri venoms. CcLAAO presents an antibacterial activity against three bacterial strains (Staphylococcus aureus, Methicillin‐resistant S. aureus, and Pseudomonas aeruginosa) with MIC values of 10, 10, and 20 μg/mL, respectively. However, no effect was observed against Escherichia coli and yeast strains. Kinetic parameters of CcLAAO evaluated on l ‐leucine at pH 8.0 and 20°C were Km = 0.06 mmol and Vmax = 164 mmol/min. 相似文献
16.
Acacia catechu, commonly known as catechu, cachou and black cutch is an important medicinal plant and an economically important forest tree.
The methanolic extract of this plant was found to have antimicrobial activities against six species of pathogenic and non-pathogenic
microorganisms: Bacillus subtilis, Staphylococcus aureus, Salmonella typhi, Escherichia coli, Pseudomonas aeruginosa and Candida albicans. The maximum zone of inhibition (20 mm) was found to be exhibited against S. aureus. For this organism the minimum bactericidal concentration (MBC) of the crude extract was 1,000 μg/ml. The extract was found
to be equally effective against gram positive and gram negative bacteria. The antimicrobial activity of the extract was found
to be decreased during purification. The chemical constituents of organic plant extracts were separated by thin layer chromatography
(TLC) and the plant extracts were purified by column chromatography and were further identified by Gas chromatography–mass
selection (GC–MS) analysis. The composition of A. catechu extract had shown major components of terpene i.e. camphor (76.40%) and phytol (27.56%) along with other terpenes in minor
amounts which are related with their high antibacterial and antifungal properties. 相似文献
17.
K. Srinivasa Babu T. Muthukumaran Aju Antony S. D. Prem Singh Samuel M. Balamurali V. Murugan S. Meenakshisundaram 《Biotechnology letters》2009,31(5):659-664
Human granulocyte-macrophage colony stimulating factor (hGMCSF) is an important therapeutic cytokine. As a novel attempt to
purify hGMCSF protein, without the enzymatic cleavage of the affinity tag, an intein-based system was used. The gene was fused
by overlap extension PCR to the intein sequence at its N-terminal in pTYB11 vector. The hGMCSF was expressed as a fusion protein in E. coli BL21(DE3), and E. coli GJ1158. In the former, the protein was expressed as inclusion bodies and upon purification the yield was 7 mg/l with a specific
activity of 0.5 × 107 IU/mg. In salt-inducible E. coli GJ1158, hGMCSF was expressed in a soluble form at 20 mg/l and a specific activity of 0.9 × 107 IU/mg. The intein-hGMCSF was purified on a chitin affinity column by cleaving intein with 50 mM DTT resulting in a highly
pure 14.7 kDa hGMCSF. 相似文献
18.
Lu Huang Xiaojie Cheng Chengsheng Liu Ke Xing Jing Zhang Gangzheng Sun Xiaoyan Li Xiguang Chen 《Frontiers of Biology in China》2009,4(3):321-327
An oleic acid-grafted chitosan oligosaccharide (CSO-OA) with different degrees of amino substitution (DSs) was synthesized
by the 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC)-mediated coupling reaction. Fourier transform infrared spectroscopy
(FT-IR) suggested the formation of an amide linkage between amino groups of chitosan oligosaccharide and carboxyl groups of
oleic acid. The critical aggregation concentrations (CACs) of CSO-OA with 6%, 11%, and 21% DSs were 0.056, 0.042, and 0.028
mg·mL−1, respectively. Nanoparticles prepared with the sonication method were characterized by means of transmission electron microscopy
(TEM) and Zetasizer, and the antibacterial activity against Escherichia coli and Staphylococcus aureus was investigated. The results showed that the CSO-OA nanoparticles were in the range of 60–200 nm with satisfactory structural
integrity. The particle size slightly decreased with the increase of DS of CSO-OA. The antibacterial trial showed that the
nanoparticles had good antibacterial activity against E. coli and S. aureus. 相似文献
19.
Antibacterial peptides have a broad range of antibacterial properties that makes them highly toxic for expression in Escherichia coli. For prepare an antiserum to detect these peptides, we developed a cecropin B mutant with a green fluorescent protein fusion
partner resulting in high expression of a 37 kDa fusion peptide in E. coli with a yield of 7.9 mg/l culture medium after purification on Ni-IDA resin. Guinea pigs when immunized with the fusion peptide
produced a specific antiserum which titers in excess of 1:25,600. 相似文献
20.
Adriana de Lima Mendonça Carlos Eduardo da Silva Fernando Lucas Torres de Mesquita Rousseau da Silva Campos Ruth R. Do Nascimento Eulália Camelo Pessoa de Azevedo Ximenes Antônio Euzébio G. Sant’Ana 《Antonie van Leeuwenhoek》2009,95(4):295-303
The secretions of the mandibular and metapleural glands of leaf cutting ants contain antimicrobial substances that protect
the mutualistic fungal colony within the nest from attack by parasitic micro-organisms. The major constituents of these secretions
(citral, 4-methyl-3-heptanol, 2-heptanone, 3-octanone, 4-methyl-2-heptanone, β-citronellol, geraniol, phenylacetic, indolacetic,
hexanoic and octanoic acids were tested against resistant strains of the human pathogens, Escherichia coli, Staphylococcus aureus and Candida albicans. Assays were carried out using filter paper discs impregnated with either hexane or water solutions of the analytes in the
concentration range 250–6,000 ng/μl. Although most of the tested compounds presented strong antibacterial and antifungal activities,
citral, geraniol, 4-methyl-3-heptanol, hexanoic and octanoic acids were the most effective, particularly against C. albicans. The results suggest that these compounds may be of potential value as antibiotics in the treatment of human candidiasis. 相似文献