香兰素抗菌机制研究进展

食品安全问题在中国范围内频发,严重威胁民众的健康和安全。为防止此类问题发生,对于由微生物污染食品所产生的危害,可通过添加抗菌剂有效降低安全隐患,随着食品安全法的不断完善,抗菌剂的添加量也愈加严格和规范。香兰素是一种具有抗菌性的传统食品添加剂,但是目前缺乏对其抗菌机制的全面理解,因此,限制了香兰素在抗菌特性方面的广泛应用。有鉴于此,现对香兰素的结构、功能与抗菌活性的相关性及其抗菌机制研究进展予以综述,并对具有抗菌特性的香兰素衍生物进行探讨。     

植物精油的抗菌特性及在食品工业中应用研究新进展

概述了植物精油和其单组分的来源、安全性评价、抗菌性能以及在食品工业上应用研究的新进展。并简要讨论了在食品应用中,食物中脂肪、蛋白、水、盐、pH等含量以及外在条件如包装、精油的添加形态和病菌的特性对植物精油的抗菌活性的影响。     

家蝇抗菌物质的诱导

针刺损伤诱导的家蝇三龄幼虫免疫血淋巴对动、植物病原菌有广谱的抗菌活性,同时,未经诱导的家蝇幼虫也具有抗菌活性。ＳＤＳ－ＰＡＧＥ电泳分析表明：外源诱导能增强原有抗菌物质的表达量,并能激活新的蛋白产生。家蝇免疫血淋巴中的抗菌物质具热稳定性和耐冷冻贮藏的特性     

抗菌塑料的抑菌效果评价

抗菌塑料是含锌离子的可溶性玻璃粉,具有杀菌、抑菌性能的新型功能材料。国外抗菌塑料的研究应用起始于20世纪80年代初。欧美国家早期在日用品中应用,近年在玩具产品上应用较多。日本在应用抗菌塑料方面发展更快。首先在家电产品中应用抗菌塑料,抗菌电话等产品一面市,就深受消费者的欢迎。抗菌材料一般具有抗菌、杀菌、防霉、消毒、除臭、防潮等功能。抗菌材料应用范围十分广泛,主要应用于家电设备、医院设施和医疗卫生器具、商店和其他公共场所的设备用具及其他生活日常用品等。随着抗菌材料研究开发的不断进展,其应用范围也必然日益广泛,功能也必然更加齐全。20世纪90年代中后期,抗菌塑料在我国飞速发展。其抗菌塑料产品不断增加,现在已经有抗菌塑料碗、塑料盘、塑料电话、以及食品加工业和餐饮业的机械设备等抗菌塑料产品在我国问世。本文根据抗菌塑料的作用原理和特性,对抗菌塑料效果进行监测探讨,为抗菌塑料的推广和应用提供依据。     

植物精油化学成分及其抗菌活性的研究进展

植物精油是一类从植物中萃取的芳香味油状液体,是一类优良的天然抗菌材料。作为抗菌材料,植物精油具有以下优点:具有广谱高效的抗菌活性;具有熏蒸特性、气味芳香;取自天然植物,绿色环保;来源广,提取容易。植物精油因其多种优点,在抗菌领域具有巨大的潜在应用价值。本文从植物精油的分布及化学成分、抗细菌活性和抗真菌活性的研究,以及植物精油化学成分与抗菌活性之间的联系等方面对植物精油的抗菌性能进行评述,以期促进植物精油在抗菌领域的广泛应用,同时给从事植物精油抗菌研究的科研工作者提供参考。     

家蝇幼虫抗菌物质组成及其理化性质

用抑菌圈、酸碱性聚丙烯酰胺凝胶电泳(PAGE)等方法,对家蝇幼虫免疫血淋巴抗菌物质组成及其理化特性进行了研究。结果表明,家蝇抗菌物质是蛋白质,呈碱性和近中性,由5种成分组成。家蝇抗菌物质有较稳定的理化特性。如对热,对较高浓度盐溶液,较极端的pH溶液,室温放置6h及冻融12次等处理均有较高的稳定性。     

医用纳米金属及其氧化物的制备、性能与抗菌应用研究进展

抗生素在临床抗菌中发挥越来越重要作用,然而,其滥用也带来了毒副反应、出现耐药病原、免疫力降低等问题,临床亟需新的抗菌方案。近年来,纳米金属及其氧化物由于广谱抗菌活性而受到广泛关注,纳米银、纳米铜、纳米锌及其氧化物等逐渐应用于生物医用领域。本文介绍了纳米金属材料分类和导电、超塑延展、催化、抗菌等基本性能;概述了物理法、化学法和生物法等常见制备技术;总结了细胞膜、氧化应激、破坏DNA和降低细胞呼吸等4种主要抗菌机理;并综述了纳米金属及其氧化物的尺寸、形状、浓度和表面化学特性对抗菌有效性的影响以及细胞毒性、遗传毒性、生殖毒性等生物安全性的研究现状。尽管目前纳米金属及其氧化物已在医用抗菌、癌症治疗等临床领域得到应用,但诸如绿色制备工艺开发、抗菌机理完善、生物安全性改进以及应用领域拓展仍有待深入探索。     

铋基纳米材料在抗菌领域的研究进展

铋(bismuth, Bi)作为一种低毒性重金属,已被用于合成各种具有独特结构和物理化学特性的纳米材料。合成的铋基纳米材料具有良好生物相容性、高X射线衰减系数、循环半衰期长、稳定性高、优异的光热转换效率和光催化能力等特点。由于这些特点,铋基纳米材料在组织工程、抗菌和癌症治疗等生物医学方面得到广泛应用。据报道,铋基纳米材料已被制成药物用于疾病治疗。与传统抗菌药物相比,铋基纳米材料在抗菌领域的应用可有效避免细菌耐药性的发生。综述了铋基纳米材料的特性、抗菌机制及其在抗菌领域的研究进展,最后提出了铋基纳米抗菌材料未来的研发方向。     

壳聚糖及其衍生物抗菌性质的研究进展

壳聚糖对多种细菌、真菌具有广谱抗菌的功能,因此它被广泛地应用于广泛地用于口腔疾病、皮肤炎症、伤口感染、胃肠道疾病等各种疾病的治疗。本文综述了壳聚糖及其衍生物对常见的口腔致病菌、皮肤癣菌、伤口感染菌以及胃肠道疾病的致病菌的抗菌作用和壳聚糖及其衍生物的抗菌机理。     

抗菌药物与机体免疫功能的相互关系

随着抗菌药物的广泛应用，在治疗各种细菌性感染疾病过程中存在下列三个方面的相互作用，即抗菌药物与细菌之间、机体免疫功能与细菌之间以及抗菌药物与机体免疫功能之间的相互作用。近几年来，由于各种因素造成免疫缺陷的病人增多，引起了不少学者关注抗菌药物对机体免疫...     

Antibacterial components of honey

The antibacterial activity of honey has been known since the 19th century. Recently, the potent activity of honey against antibiotic-resistant bacteria has further increased the interest for application of honey, but incomplete knowledge of the antibacterial activity is a major obstacle for clinical applicability. The high sugar concentration, hydrogen peroxide, and the low pH are well-known antibacterial factors in honey and more recently, methylglyoxal and the antimicrobial peptide bee defensin-1 were identified as important antibacterial compounds in honey. The antibacterial activity of honey is highly complex due to the involvement of multiple compounds and due to the large variation in the concentrations of these compounds among honeys. The current review will elaborate on the antibacterial compounds in honey. We discuss the activity of the individual compounds, their contribution to the complex antibacterial activity of honey, a novel approach to identify additional honey antibacterial compounds, and the implications of the novel developments for standardization of honey for medical applications.     

A comparison of the sensitivity of wound-infecting species of bacteria to the antibacterial activity of manuka honey and other honey.

Both honey and sugar are used with good effect as dressings for wounds and ulcers. The good control of infection is attributed to the high osmolarity, but honey can have additional antibacterial activity because of its content of hydrogen peroxide and unidentified substances from certain floral sources. Manuka honey is known to have a high level of the latter. Seven major wound-infecting species of bacteria were studied to compare their sensitivity to the non-peroxide antibacterial activity of manuka honey and to a honey in which the antibacterial activity was primarily due to hydrogen peroxide. Honeys with activity in the middle of the normal range were used. A comparison of the median response of the various species of bacteria showed no significant difference between the two types of activity overall, but marked differences between the two types of activity in the rank order of sensitivity of the seven bacterial species. The non-peroxide antibacterial activity of manuka honey at a honey concentration of 1.8% (v/v) completely inhibited the growth of Staphylococcus aureus during incubation for 8 h. The growth of all seven species was completely inhibited by both types of honey at concentrations below 11% (v/v).     

A comparison of the sensitivity of wound-infecting species of bacteria to the antibacterial activity of manuka honey and other honey

Both honey and sugar are used with good effect as dressings for wounds and ulcers. The good control of infection is attributed to the high osmolarity, but honey can have additional antibacterial activity because of its content of hydrogen peroxide and unidentified substances from certain floral sources. Manuka honey is known to have a high level of the latter.
Seven major wound-infecting species of bacteria were studied to compare their sensitivity to the non-peroxide antibacterial activity of manuka honey and to a honey in which the antibacterial activity was primarily due to hydrogen peroxide. Honeys with activity in the middle of the normal range were used. A comparison of the median response of the various species of bacteria showed no significant difference between the two types of activity overall, but marked differences between the two types of activity in the rank order of sensitivity of the seven bacterial species. The non-peroxide antibacterial activity of manuka honey at a honey concentration of 1.8% (v/v) completely inhibited the growth of Staphylococcus aureus during incubation for 8 h. The growth of all seven species was completely inhibited by both types of honey at concentrations below 11% (v/v).     

Antibacterial activity of honey from stingless honeybees (Hymenoptera; Apidae; Meliponinae).

The aim of the study was to examine antibacterial activity of the honey of stingless honeybees (Meliponinae). An agar well diffusion assay demonstrated that many honey samples of stingless honeybees inhibited the growth of test strains of Staphylococcus aureus, Enterococcus faecalis, Escherichia coli and Pseudomonas aeruginosa; moreover, they exhibited non-peroxide antibacterial activity against those strains. This is the first time that non-peroxide antimicrobial activity of honey from a number of species of stingless honeybees has been demonstrated. These antibacterial activities appear to be powerful, even when compared to those of"manuka honey" from Apinae honeybees.     

Antibacterial activity of honey and propolis from Apis mellifera and Tetragonisca angustula against Staphylococcus aureus

AIMS: The antibacterial activity against Staphylococcus aureus of honey and propolis produced by Apis mellifera and Tetragonisca angustula was evaluated. Secondary aims included the study of the chemical composition of propolis and honey samples and its relationship with antibacterial activity against S. aureus. METHODS AND RESULTS: The antibacterial activity of honey and propolis was determined by the method of macrodilution. The minimum inhibitory concentration (MICs) of A. mellifera honey ranged from 126.23 to 185.70 mg ml(-1) and of T. angustula from 142.87 to 214.33 mg ml(-1). For propolis, the MIC ranged from 0.36 to 3.65 mg ml(-1) (A. mellifera) and from 0.44 to 2.01 mg ml(-1) (T. angustula). Honey and propolis were evaluated by high-performance liquid chromatography. Some typical compounds of Brazilian propolis were also identified in honey samples. Principal component analysis revealed that the chemical composition of honey and propolis samples was distinct based on the geographical location of the samples. CONCLUSIONS: Propolis samples had higher antibacterial activity against S. aureus when compared with honey. However, both propolis and honey samples had antibacterial against S. aureus. SIGNIFICANCE AND IMPACT OF THE STUDY: These antimicrobial properties would warrant further studies on the clinical applications of propolis and honey against S. aureus.     

In vitro effect of some Indian honeys on Staphylococcus aureus from wounds

Staphylococcus aureus is the most frequently isolated pathogen from wounds with multiple resistances to antibiotics. Honey has been demonstrated and reported to be effective antibacterial agent on Gram positive and Gram negative organisms. Hence, the present study was conducted to evaluate the in vitro antibacterial effect of Indian honeys on Staphylococcus aureus obtained from wounds. A total of 123 Staphylococcus aureus isolates along with ATCC 25923 were categorized as sensitive, multi drug resistant (MDR) and non-MDR strains. Out of total nine Indian honeys (three each of unifloral, multifloral and branded marketed honey) used, three unifloral and three multifloral honey samples showed antibacterial activity against all the organisms tested by Agar diffusion method but not the branded marketed honeys. The MIC values of all honey samples for all studied Staphylococcus aureus isolates ranged between 5-15% (v/v). Unifloral honey samples showed higher antibacterial activity than multifloral honey. The single sample of Jambhul honey showed the highest activity. Thus, Indian honeys were found to be effective for their antimicrobial activity on sensitive, non-MDR, MDR and ATCC strains of S. aureus.     

Antibacterial potential of some Saudi honeys from Asir region against selected pathogenic bacteria

Honey is a nutrient rich natural product and has been utilized as traditional and complementary medicine since ancient times. In this study, antibacterial activity of Sider (Ziziphus spina-christi), Dharm (Lavandula dentata), and Majra (Hypoestes forskaolii) honey samples collected from Asir region of Saudi Arabia was in vitro evaluated at 80% and 50% w/v concentrations against five pathogenic bacteria i.e. Escherichia coli, Proteus mirabilis, Staphylococcus aureus, Shigella flexneri, and Staphylococcus epidermidis. Well diffusion assays to measure the average zone of inhibition (ZOI) and minimum inhibitory concentration (MIC) values were employed in the experiments. All the tested honey samples showed antibacterial activity in a dose-dependent manner. Sider and Dharm exhibited a good antibacterial activity at high concentrations while, Majra honey of Apis mellifera jemenitica and of Apis florea showed comparatively low antibacterial activity. The average MIC values of Sider, Dhram from Rijal Alma, Dharm from Al-Souda, Majra (A.m. jemenitica), and Majra (A. florea) honey against all tested bacteria were 22%, 16%, 18%, 32%, and 28% (v/v) respectively. Dharm and Sider honeys showed better antibacterial activity than Majra honey. Saudi honey can be considered as a promising future antimicrobial agent and should be further investigated as an alternative candidate in the management of resistant bacterial pathogens.     

Floral markers and biological activity of Saudi honey

The objectives of this research were to identify certain chemical compounds that may be used as fingerprints of Saudi honey and to evaluate their antioxidant and antibacterial activities. Eleven Saudi ‘monofloral’ honey samples were analyzed and evaluated. Non-phenolic compounds, such as 2,3-dihydro-3,5-dihydroxy-6-methyl-4H-pyran-4-one, methyl 3-hydroxyhexanaote and 5-hydroxymethyl-2-furancarboxaldehyde were present in different types of tested honey samples. Glyceraldehyde was only detected in five of the honey samples tested. The most promising result was the detection of an alkaloid (by using GC–MS) in only two types of Saudi honey samples. This alkaloid may be of great importance and has the potential to be used as a fingerprint marker for the botanical sources of the various honey samples tested. This alkaloid was present in Toran and Saha. The detected compound is 2-amino-4-hydroxypteridine-6-carboxylic acid, which may originate from the degradation of folic acid as identified by previous studies. These findings can be used as a gateway to obtain a fingerprint for these two types of honey samples and can potentially be used to track any impurities in honey sold on the market. All of the tested honey samples showed antioxidant and antibacterial activities. The highly effective activity was in Toran honey against Staphylococcus aureus and Methicillin resistant Staphylococcus aureus (MRSA). Shafalah honey was effective against MRSA and Acinetobacter baumannii which showed bactericidal effects at concentrations 70–100%. This study also examined the antioxidant activity of honey samples using the DPPH assay. DPPH values of tested honey samples varied between 53.93?±?0.21%, as the highest value and 5.89?±?0.125%, as the lowest value. Significant correlations between the antibacterial and the antioxidant activities of the tested honey samples were noticed. The corresponding total phenolic contents (TPC) values supported the fact that phenolic compounds enhanced the antibacterial activity. The study revealed that some of the locally produced honey samples, specifically Zaitoon, Shaflah, Saha, Rabea Aja and Bareq contained the monosaccharides called glyceraldehydes which was the precursor to produce methylglyoxal (MGO) compound, which has antibacterial effects as documented in several previous studies. There was no clear relationship between these activities and the sum total of phenolic compounds present in Saudi honey.     

Potential effects of Saudi Shaoka (Fagonia bruguieri) honey against multi-drug-resistant bacteria and cancer cells in comparison to Manuka honey

The global spread of antimicrobial-resistant infectious diseases and cancer are the most widespread public health issue and has led to high mortality rates. This study aims to evaluate and verify the antibacterial and antitumor activities of Shaoka and Manuka honey against pathogenic bacteria, human hepatocarcinoma (HepG2) and breast cancer (MCF-7) cell lines. Shaoka hone was analyzed using HPLC, UV–vis, and GC/MC, while antibacterial activity was measured by agar diffusion, broth microdilution methods, and Transmission Electron Microscopy (TEM). Antitumor activity was investigated morphologically and by MTT assay. According to the presented data of HPLC analysis, Shaoka honey was generally richer in polyphenolic components, the antibacterial activity showed that Shaoka honey is equivalent or relatively more active than Manuka honey against a broad spectrum of multi-drug-resistant bacteria. It inhibited the growth of ESBL Escherichia coli in the absence or presence of catalase enzyme with a concentration approximately 8.5%–7.3% equivalent to phenol, which supported the highest level of non-peroxide-dependent activity. The minimum bactericidal concentrations (MBCs) ranged between 5.0% and 15.0% honey (w/v). TEM observation revealed distorted cell morphology, cytoplasmic shrinkage, and cell wall destruction of treated bacteria. The selected honey exerted cytotoxicity on both cancer cell lines, inhibiting cell proliferation rate and viability percent in HepG2 and MCF-7 cancer cells, by different degrees depending on the honey quality, Shaoka honey competed Manuka inhibitory effects against both cancer cells. The obtained data confirmed the potential for use of Saudi Shaoka honey as a remedy, this well introduces a new honey template as medical-grade honey for treating infectious disease and cancer.     

Effect of hydrogen peroxide on antibacterial activities of Canadian honeys

Honey is recognized as an efficacious topical antimicrobial agent in the treatment of burns and wounds. The antimicrobial activity in some honeys depends on the endogenous hydrogen peroxide content. This study was aimed to determine whether honey's hydrogen peroxide level could serve as a honey-specific, activity-associated biomarker that would allow predicting and assessing the therapeutic effects of honey. Using a broth microdilution assay, I analyzed antibacterial activities of 42 Canadian honeys against two bacterial strains: Escherichia coli (ATCC 14948) and Bacillus subtilis (ATCC 6633). The MIC90 and MIC50 were established from the dose-response relationship between antibacterial activities and honey concentrations. The impact of H2O2 on antibacterial activity was determined (i) by measuring the levels of H2O2 before and after its removal by catalase and (ii) by correlating the results with levels of antibacterial activities. Canadian honeys demonstrated moderate to high antibacterial activity against both bacterial species. Both MIC90 and MIC50 revealed that the honeys exhibited a selective growth inhibitory activity against E. coli, and this activity was strongly influenced by endogenous H2O2 concentrations. Bacillus subtilis activity was marginally significantly correlated with H2O2 content. The removal of H2O2 by catalase reduced the honeys' antibacterial activity, but the enzyme was unable to completely decompose endogenous H2O2. The 25%-30% H2O2 "leftover" was significantly correlated with the honeys' residual antibacterial activity against E. coli. These data indicate that all Canadian honeys exhibited antibacterial activity, with higher selectivity against E. coli than B. subtilis, and that these antibacterial activities were correlated with hydrogen peroxide production in honeys. Hydrogen peroxide levels in honey, therefore, is a strong predictor of the honey's antibacterial activity.