Etching of Ag nanoparticles triggered bidirectional regulation for electrochemiluminescence ratiometric immunoassay.

A highly efficient ratiometric electrochemiluminescence (ECL) immunoassay was explored by bidirectionally regulating the ECL intensity of two luminophors. The immunoassay was conducted in a split-type mode consisting of an ECL detection procedure and a sandwich immunoreaction. The ECL detection was executed using a dual-disk glassy carbon electrode modified with two potential-resolved luminophors (g-C3N4-Ag and Ru-MOF-Ag nanocomposites), and the sandwich immunoreaction using glucose oxidase (GOx)-modified SiO2 nanospheres as labels was carried out in a 96-well plate. The Ag nanoparticles (NPs) acted as bifunctional units both for triggering the resonance energy transfer (RET) with g-C3N4 and for accelerating the electron transfer rate of the Ru-MOF-Ag ECL reaction. When the H2O2 catalyzed by GOx in the 96-well plate was transferred to the dual-disk glass carbon electrode, the doped Ag NPs in the two luminophors could be etched, thus destroying the RET between C3N4 and the accelerated reaction to Ru-MOF, resulting in an opposite trend in the ECL signal outputted from the dual disks. Using the ratio of the two signals for quantification, the constructed immunosensor for a model target, i.e. myoglobin, exhibited a low detection limit of 4.7 × 10-14 g/mL. The ingenious combination of ECL ratiometry, bifunctional Ag NPs, and a split-type strategy effectively reduces environmental and human errors, offering a more precise and sensitive analysis for complex samples.

H2O2-activated independently bidirectional regulation for a sensitive and accurate electrochemiluminescence ratiometric analysis.

Potential-resolved electrochemiluminescence (ECL) ratiometric analysis has become a research hotspot in bioassays by virtue of its good accuracy, versatility and specificity. Current ECL ratiometry mainly focuses on the competition for the co-reactant or quantitative analysis using a variable signal and a changeless signal; the disorganized change or small difference between the two signals may affect the accuracy and sensitivity of detection. In this study, we have developed a novel ECL ratiometric sensor based on the bidirectional regulation of two independent co-reaction systems by H2O2. H2O2 as a bidirectional moderator permits the ECL signals of the cathode and anode to independently change in opposite trends, which greatly enhances the organization and difference between the two signals. The ratio of the two signals is used to realize the quantitative analysis of myoglobin (MyO) with a good linear relationship between log(ECLcathode/ECLanode) and log CMyO in the range of 1.0 × 10-13 to 1.0 × 10-7 g mL-1. The detection limit is 4.0 × 10-14 g mL-1. Furthermore, it showed excellent performance in the determination of MyO in human serum samples. The proposed biosensor provides some developments for the sensitive and accurate detection of disease markers.

Dual-wavelength electrochemiluminescence ratiometry for hydrogen sulfide detection based on Cd2+-doped g-C3N4 nanosheets.

Herein, a novel and facile dual-wavelength ratiometric electrochemiluminescence-resonance energy transfer (ECL-RET) sensor for hydrogen sulfide (H2S) detection was constructed based on the interaction between S2- and Cd2+-doped g-C3N4 nanosheets (NSs). Cd2+-doped g-C3N4 NSs exhibited a strong ECL emission at 435 nm. In the presence of H2S, CdS was formed in situ on g-C3N4 NSs by the adsorption of S2- and Cd2+, generating another ECL emission at 515 nm. Furthermore, the overlapping of the absorption spectrum of the formed CdS and the ECL emission spectrum of g-C3N4 NSs led to a feasible RET, thus quenching the ECL intensity from g-C3N4 at 435 nm. Through an ECL decrease at 435 nm and an increase at 515 nm, a dual-wavelength ratiometric ECL-RET system for H2S was designed. The sensor exhibited a lower detection limit of 0.02 µM with a wide linear range of 0.05-100.0 µM. In addition, the applicability of the method was validated by plasma sample analysis with a linear range of 80.0-106.0%. We believe that such a proposal would provide new insight into advanced dual-wavelength ECL ratiometric assays.

Culture and in situ H2O2-mediated electrochemical study of cancer cells using three-dimensional scaffold based on graphene foam coated with Fe3O4 nanozyme.

For real-time evaluation of the cell behavior and function under in vivo-like 3D environment, the 3D functionalized scaffolds simultaneously integrate the function of 3D cell culture, and electrochemical sensing is a convincing candidate. Herein, Fe3O4 nanoparticles as the nanozyme (peroxide oxidase mimics) were modified on graphene foam scaffold to construct a 3D integrated platform. The platform displayed a wide linear range of 100 nM to 20 µM and a high sensitivity of 53.2 nA µM-1 toward detection of hydrogen peroxide (H2O2) under the working potential of + 0.6 V (vs. Ag/AgCl). The obtained 3D scaffold also displayed satisfactory selectivity toward the possible interferents that appeared in the cell culture environment. Furthermore, the cells still maintained high cell viability (almost 100%) after their growth and proliferation on the scaffold for 7 days. With the superior performance on cell culture and electrochemical monitoring, the functions on the 3D culture of MCF-7 or HeLa cells and in situ monitoring of cell-released H2O2 was easily achieved on this 3D platform, which show its great application prospects on further cancer-related disease diagnosis or drug screening. A nanozyme-based three-dimensional graphene scaffold was successfully constructed for cell culture and identification of cancer cells through in situ electrochemical monitoring of the cell-released H2O2.

Photogenerated Hole-Induced Chemical-Chemical Redox Cycling Strategy on a Direct Z-Scheme Bi2S3/Bi2MoO6 Heterostructure Photoelectrode: Toward an Ultrasensitive Photoelectrochemical Immunoassay.

To achieve high sensitivity for biomolecule detection in photoelectrochemical (PEC) bioanalysis, the ideal photoelectrode and ingenious signaling mechanism play crucial roles. Herein, the feasibility of the photogenerated hole-induced chemical-chemical redox cycling amplification strategy on a Z-scheme heterostructure photoelectrode was validated, and the strategy toward enhanced multiple signal amplification for advanced PEC immunoassay application was developed. Specifically, a direct Z-scheme Bi2S3/Bi2MoO6 heterostructure was synthesized via a classic hydrothermal method and served as a photoelectrode for the signal response. Under the illumination, the PEC chemical-chemical redox cycling (PECCC) among 4-aminophenol generated by the enzymatic catalysis from a sandwich immunoassay, ferrocene as a mediator, and tris (2-carboxyethyl) phosphine as a reducing agent was run on the Z-scheme Bi2S3/Bi2MoO6 heterostructure photoelectrode. Exemplified by interleukin-6 (IL-6) as the target, the applicability of the strategy was studied in a PEC immunoassay. Thanks to the multiple signal amplification originating from the high efficiency of the PECCC redox cycling system, the enzymatic amplification, and the fine performance of the Z-scheme Bi2S3/Bi2MoO6 heterostructure photoelectrode, the assay for IL-6 exhibits a very low detection limit of 2.0 × 10-14 g/mL with a linear range from 5.0 × 10-14 to 1.0 × 10-8 g/mL. This work first validates the feasibility of the PECCC redox cycling on the Z-scheme heterostructure photoelectrode and the good performance of the strategy in PEC bioanalysis. We envision that it would provide a new prospective for highly sensitive PEC bioanalysis on the basis of a Z-scheme heterostructure.

Liposome-assisted enzyme catalysis: toward signal amplification for sensitive split-type electrochemiluminescence immunoassay.

Developing an efficient signal amplification strategy is very important to improve the sensitivity of bioanalysis. In this paper, a liposome-assisted enzyme catalysis signal amplification strategy was developed for electrochemiluminescence (ECL) immunoassay of prostate specific antigen (PSA) in a split-type mode. The sandwich immunoreaction occurred in a 96-well plate, and glucose oxidase (GOx) encapsulated and antibody-modified liposomes were used as labels. The ECL detection was carried out using a rGO-Au NP modified glassy carbon electrode (GCE). The large amount of generated H2O2, i.e. the coreactant of the luminol system, and the excellent catalytic behavior of rGO-Au NPs greatly boosted the ECL signal, resulting in the signal amplification. The developed ECL immunosensor for detecting PSA achieved a wider linear range from 1.0 × 10-13 to 1.0 × 10-8 g mL-1 and a detection limit of 1.7 × 10-14 g mL-1. The application of the proposed strategy was demonstrated by analyzing PSA in human serum samples with recoveries from 89.0% to 113.0%, and relative standard deviations (RSDs) were less than 6.6%. This work provides a new horizon to expand the application of liposomes for ECL bioanalysis.

L-Histidine-DNA interaction: a strategy for the improvement of the fluorescence signal of poly(adenine) DNA-templated gold nanoclusters.

An interesting phenomenon is described that the fluorescence signal of poly(adenine) (A) DNA-templated gold nanoclusters (AuNCs) is greatly improved in the presence of L-histidine by means of L-histidine-DNA interaction. The modified nanoclusters display strong fluorescence emission with excitation/emission maxima at 290/475 nm. The fluorescence quantum yield (QY) is improved from 1.9 to 6.5%. Fluorescence enhancement is mainly ascribed to the L-histidine-DNA interaction leading to conformational changes of the poly(A) DNA template, which offer a better microenvironment to protect AuNCs. The assay enables L-histidine to be determined with good sensitivity and a linear response that covers the 1 to 50 nM L-histidine concentration range with a 0.3 nM limit of detection. The proposed method has been applied to the determination of imidazole-containing drugs in pharmaceutical samples. A turn-on fluorescent method has been designed for the sensitive detection of L-histidine as well as imidazole-containing drugs on the basis of the L-histidine-DNA interaction.

A turn-on fluorescence strategy for cellular glutathione determination based on the aggregation-induced emission enhancement of self-assembled copper nanoclusters.

As a class of ideal fluorescent nanomaterials, self-assembled copper nanoclusters (CuNCs) have attracted increasing interest. Unfortunately, most of these CuNCs only possessed bright luminescence in acidic solution, which limited their practical applications in a physiological environment. Retaining the strong fluorescence of these CuNCs in neutral or alkaline solution is still a challenging task. In this strategy, self-assembled CuNCs were prepared by using 4-methylthiophenol as the protecting ligand. The self-assembled CuNCs display stable and bright luminescence with excitation/emission maxima at 330/605 nm even in neutral and alkaline environments. Interestingly, with the addition of glutathione (GSH), the fluorescence intensity of CuNCs is enhanced strongly through the GSH-controlled aggregation-induced emission enhancement of self-assembled CuNCs. The turn-on fluorescence strategy can determine the GSH concentration in the range from 1 to 100 µM with a limit of detection of 300 nM. In addition, the method is employed for the determination of GSH levels in cells. Therefore, the turn-on fluorescence strategy is reliable, sensitive and suitable for the determination of cellular GSH levels.

Recent progress of heterostructure-based photoelectrodes in photoelectrochemical biosensing: a mini review.

Photoelectrochemical (PEC) biosensing has received increasing attention due to its great potential in the analysis of biomarkers. The performance of a PEC biosensor depends largely on photosensitive materials. The photoactive materials with excellent properties are of great importance to realize advanced PEC bioassays. Recently, as a special class of nanocomposites, heterostructures consisting of different types of semiconductors with potential applications in PEC systems have witnessed the rapid development to improve the performance of PEC biosensors. In this review, the research progress on the promising heterostructures has been introduced and summarized, and the applications of such heterostructures in PEC bioassays are provided. The future development of heterostructures pertaining to PEC biosensing systems has also been briefly discussed.

A turn-on fluorescence strategy for biothiols determination by blocking Hg(II)-mediated fluorescence quenching of adenine-rich DNA-templated gold nanoclusters.

Fluorescent adenine (A)-rich DNA-templated gold nanoclusters were demonstrated to be a novel probe for determination of biothiols (including cysteine, glutathione, and homocysteine). Fluorescence intensity of adenine-rich DNA-templated gold nanoclusters could be greatly quenched by Hg(II) ions through the formation of a gold nanoclusters-Hg(II) system. When biothiols (cysteine as the model) were introduced into the system, the fluorescence intensity recovered due to the formation of a more stable Hg(II)-thiol coordination complex using Hg-S metal-ligand bonds, which inhibited the Hg(II)-mediated fluorescence quenching of adenine-rich DNA-templated gold nanoclusters. Based on this fluorescence phenomenon, an on-off-on fluorescence strategy was designed for the sensitive determination of biothiols. The method allowed sensitive detection of cysteine with a linear detection range from 100 nM to 5 µM and a limit of detection of 30 nM. Additionally, the assay can be applied for detection of biothiol levels in human plasma samples. Therefore, it can provide a simple and rapid fluorescent platform for biothiol detection.

Highly selective fluorimetric and colorimetric sensing of mercury(II) by exploiting the self-assembly-induced emission of 4-chlorothiophenol capped copper nanoclusters.

A highly stable copper nanoclusters (CuNC) carrying 4-chlorothiophenol as a protective ligand is described. They display self-assembly-induced emission with excitation/emission maxima at 330/605 nm even in neutral or alkaline aqueous environment. The fluorescence of these CuNC is quenched by Hg(II). Quenching is mainly ascribed to the formation of a complex formed via Hg-S bonding between the Hg(II) ions and the ligand. This destroys the ordered architectures of the assembled CuNC. The assay enables Hg(II) to be determined with good sensitivity and a linear response ranging from 1 to 500 nM Hg(II) with a 0.3 nM limit of detection. In addition, the method was implemented in a test strip (which undergoes a color change from red to blue) that can be used for visual determination of Hg(II) in complex environmental water samples. Graphical abstractNovel and highly selective fluorimetric and colorimetric methods have been designed for mercury(II) ions determination based on stable self-assembly-induced emission of copper nanoclusters.

Ru(NH3)63+/Ru(NH3)62+-Mediated Redox Cycling: Toward Enhanced Triple Signal Amplification for Photoelectrochemical Immunoassay.

Herein we report an effective Ru(NH3)63+/Ru(NH3)62+-mediated photoelectrochemical-chemical-chemical (PECCC) redox cycling amplification (RCA) strategy toward enhanced triple signal amplification for advanced split-type PEC immunoassay application. Specifically, alkaline phosphatase (ALP) label was confined via a sandwich immunorecognition to convert 4-aminophenyl phosphate to the signal reporter 4-aminophenol (AP), which was then directed to interact with Ru(NH3)62+ as a redox mediator and tris (2-carboxyethyl) phosphine (TCEP) as reducing agent in the detection buffer. Upon illumination, the system was then operated upon the oxidation of Ru(NH3)62+ by the photogenerated holes on the Bi2S3/BiVO4 photoelectrode, starting the chain reaction in which the Ru(NH3)62+ was regenerated by Ru(NH3)63+-enabled oxidization of AP to p-quinoneimine, which was simultaneously recovered by TCEP. Exemplified by interleukin-6 (IL-6) as the analyte, the Ru(NH3)63+/Ru(NH3)62+-mediated, AP-involved PECCC RCA coupled with ALP enzymatic amplification could achieve triple signal amplification toward the ultrasensitive PEC IL-6 immunoassay. This protocol can be extended as a general basis for other numerous targets of interest. Besides, we believe this work could offer a new perspective for the further exploration of advanced RCA-based PEC bioanalysis.

Reduced graphene oxide-gold nanoparticles-catalase-based dual signal amplification strategy in a spatial-resolved ratiometric electrochemiluminescence immunoassay.

A novel spatial-resolved electrochemiluminescent (ECL) ratiometry for cardiac troponin I (cTnI) analysis was developed using resonance energy transfer (RET) and a coreactant consumption strategy for signal amplification. Specifically, the spatial-resolved dual-disk glassy carbon electrodes were modified with CdS nanowires (CdS NWs) and luminol-gold nanoparticles (L-Au NPs) as potential-resolved ECL emitters, respectively. After stepwise immobilization of anti-cTnI and bovine serum albumin on the dual-disk electrodes, the CdS NWs-based electrode, with varied concentrations of cTnI, was used to provide a working signal, whereas the L-Au NPs-based electrode, with a fixed amount of cTnI, was employed to provide the reference signal. To efficiently amplify the working signal on the CdS NWs-based electrode, an anti-cTnI-reduced graphene oxide-gold nanoparticles-catalase probe (anti-cTnI-rGO-Au NPs-CAT) was loaded onto the electrode to form a sandwich immunocomplex. The RET from CdS NWs to Au NPs and the coreactant (i.e. H2O2) consumption by the CAT generate a significant ECL decrease on the CdS NWs-based electrode in the presence of cTnI. This novel and sensitive ratiometric detection mode for cTnI was achieved using the ratio values of the working signal of the CdS NWs-based electrode and the reference signal of the L-Au NPs-based electrode. The integration of RET and coreactant consumption strategy in the designed spatial-resolved ratiometric platform endows the immunosensor with a wide linear range of 5.0 × 10-13 - 1.0 × 10-7 g mL-1 and a low detection limit of 0.10 pg mL-1 for cTnI. Furthermore, the method exhibits high accuracy and sensitivity for cTnI determination in human serum samples.

Photoelectrochemical-Chemical-Chemical Redox Cycling for Advanced Signal Amplification: Proof-of-Concept Toward Ultrasensitive Photoelectrochemical Bioanalysis.

Signal amplification is essential for ultrasensitive photoelectrochemical (PEC) bioanalysis. Exploration of the facile and efficient route for multiple signal amplification is highly appealing. Herein, we present the concept of photoelectrochemical-chemical-chemical (PECCC) redox cycling as an advanced signal amplification route and a proof-of-concept toward ultrasensitive PEC bioanalysis. The system operated upon the bridging between the enzymatic generation of signaling species ascorbic acid (AA) from a sandwich immunoassay and the PECCC redox cycling among the ferrocenecarboxylic acid as redox mediator, the AA, and the tris(2-carboxyethyl)phosphine as reducing agent at the Bi2S3/Bi2WO6 photoelectrode. Exemplified by myoglobin (Myo) as target, the proposed system achieved efficient regeneration of AA and thus signal amplification toward the ultrasensitive split-type PEC immunoassay. This work first exploited the PECCC redox cycling, and we believe it will attract more interest in the research of PEC bioassays on the basis of advanced redox cycling.

Immuno-Electrochemiluminescent Imaging of a Single Cell Based on Functional Nanoprobes of Heterogeneous Ru(bpy)32+@SiO2/Au Nanoparticles.

It is valuable to develop a sensing platform for not only detecting a tumor marker in body fluids but also measuring its expression at single cells. In the present study, a simple closed bipolar electrodes-based electrochemiluminescence (BPEs-ECL) imaging strategy was developed for visual immunoassay of prostate specific antigen (PSA) at single cells using functional nanoprobes of heterogeneous Ru(bpy)32+@SiO2/Au nanoparticles. Multiple-assisted ECL signal amplification strategy was introduced into the detection system on the basis of the synergetic amplifying effect of the anodic and cathodic amplification. On the basis of the synergetic amplifying effect, the detection limits of PSA by using photomultiplier tube and charge-coupled device (CCD) imaging are 3.0 and 31 pg/mL, respectively. The obtained immunosensor was employed to evaluate PSA levels in serum samples with a satisfying result. Moreover, the obtained functional nanoprobes were used to visually profile the PSA expression on the surface of single LNCaP cells (a kind of prostate cancer cells) based on a bare BPE. The results show that the functional nanoprobes-based ECL imaging immunoassay provides a promising visual platform for detecting tumor markers (proteins and cancer cells) and thus shows a high potential in cancer diagnosis.

Cathodic electrochemiluminescence behaviour of MoS2 quantum dots and its biosensing of microRNA-21.

The cathodic electrochemiluminescence (ECL) behaviour of nontoxic MoS2 quantum dots (QDs) was studied for the first time using potassium peroxydisulfate as the co-reactant. Ag-PAMAM NCs, serving as difunctional tags for quenching and enhancing ECL of MoS2-reduced graphene oxide composites, were introduced into the ECL detection system for signal amplification. By modulating the interparticle distance between MoS2 QDs and Ag-PAMAM NCs, the ECL quenching from resonance energy transfer and the ECL enhancement from surface plasma resonance were realized. Coupling the good ECL performance of MoS2 QDs with the excellent ECL quenching and enhancement effects of Ag-PAMAM NCs, a novel MoS2 QDs-based ECL biosensing platform for sensitive detection of microRNA-21 was achieved with a detection limit of 0.20 fmol L-1 (S/N = 3). This method was successfully applied to the determination of microRNA-21 in human serum samples with recoveries of 90.0-110.0%, suggesting great potential for its applications in biological and chemical analysis.

Bacteriocin Isolated from Lactobacillus Rhamnosus L34 Has Antibacterial Effects in a Rabbit Model of Infection After Mandible Fracture Fixation.

BACKGROUND Rigid internal fixation (RIF) technology is a recently developed fracture fixation technique in which use of specific antibiotics before and after the operation and timely treatment of local infections is necessary. MATERIAL AND METHODS The bacteriocins were isolated from Lactobacillus rhamnosus L34. Twenty-four New Zealand White female rabbits were divided into 2 groups: bacteriocins and control group. After mandible fracture fixation, the rabbits were infected with S. aureus and subsequently injected with either bacteriocins or saline. The biofilm samples were harvested from rabbits euthanized on the 1st, 3rd, and 5th days and observed using a fluorescence microscope. Blood samples were collected at 1 h, 12 h, 1 day, 3 days, and 5 days after the injection of either bacteriocin or saline to test the level of C-reactive protein and TNF-α. RESULTS Significant differences in the biofilm formation were evident between the bacteriocins and saline treatment group on days 1, 3, and 5. Moreover, the serum levels of TNF-α and CRP after treatment with bacteriocins were significantly lower than in controls. CONCLUSIONS Use of bacteriocins isolated from Lactobacillus rhamnosus L34 may be a promising way to control infections of mandible fracture after internal fixation in vivo.

Determination of the activity of alkaline phosphatase by using nanoclusters composed of flower-like cobalt oxyhydroxide and copper nanoclusters as fluorescent probes.

The authors describe a sensitive fluorometric method for the determination of the activity of alkaline phosphatase (ALP). It is based on the use of a composite prepared consisting of flower-like cobalt oxyhydroxide (CoOOH) and copper nanoclusters (CuNCs). On formation of the CuNC-CoOOH aggregates, the fluorescence of the CuNCs is quenched by the CoOOH sheets. If, however, the CoOOH sheets are reduced to Co(II) ions in the presence of ascorbic acid (AA), fluorescence recovers. AA is formed in-situ by hydrolysis of the substrate ascorbic acid 2-phosphate (AA2P) as catalyzed by ALP. Thus, the ALP activity can be detected indirectly by kinetic monitoring of the increase in fluorescence, best at excitation/emission wavelengths of 335/410 nm. The assay allows ALP to be determined in 0.5 to 150 mU·mL-1 activity range and with a 0.1 mU·mL-1 detection limit. The method was successfully applied to the determination of ALP activity in (spiked) human serum samples. The assay has attractive features in being of the off-on type and immune against false positive results. Graphical Abstract A fluorescent bioassay is reported for the determination of the activity of alkaline phosphatase (ALP). It is exploiting the ascorbic acid (AA)-induced decomposition of nanoclusters composed of flower-like cobalt oxyhydroxide and copper nanoclusters. ALP catalyzes hydrolysis of ascorbic acid 2-phosphate (AA2P) and dephosphorylation to form AA.

[Diversity, antibacterial activites and growth promoting characteristics of endophytic fungi from sandal (Santalum album)].

The aim of this study was to investigated the biological diversity, antibacterial activites and the plant growth-promoting traits of endophytic fungi of sandal (Santalum album), and to assess their potential in the development of antibacterial substances and rapid cultivation of sandal. The results of isolation and taxa analysis of endophytic fungi from sandal showed that 325 strains of endophytic fungi belonging to 16 genera of endophytic fungi were isolated from sandal (of which 86 from roots, 105 from stems and 134 from leaves). The isolation rate and colonization rate of endophytic fungi in different sandal parts showed the same pattern of change: leave>stems>roots. The diversity index of endophytic fungi in sandal roots was significantly higher than that of stems and leaves. The dominant endophytic fungi of sandal roots, stems and leaves showed significant differences. The dominant endophytic fungi of roots were Fusarium (50.00%) and Alternaria (10.47%), Alternaria (58.11%) and Acremonium (20.00%) for stems, and Pantoea (74.63%) for leaves. The antibacterial activity of 40 representative strains of sandal endophytic fungi were analyzed and the results showed that 90% of endophytic fungi exhibited inhibitory activity against at least one of the tested bacteria strains, and the strains with inhibitory activity to Escherichia coli, Enterobacter aerogenes, Shigella dysenteriae, Salmonella typhimurium, Staphylococcus aureus, and Bacillus subtilis accounted for 45.0%, 30%, 47.5%, 55%, 72.5%, and 62.5%, respectively. The sandal fungal endophytes with plant growth-promoting characteristics were screened, and 5 strains of endophytic fungi with phosphorus-solubilizing activity, 8 strains of endophytic fungi producing IAA, and 4 strains of endophytic fungi producing siderophores were found. Among them, endophytic fungus Monilia sp TXRF45 clould produced IAA and siderophores, and also show phosphate-solubilizing activity. The results indicated that the endophytic fungi of Sandal were rich in species diversity and their distribution had a certain tissue specificity. Some strains showed good antibacterial activity and growth-promoting properties, which could potentially applicable for the development of antibacterial substances and rapid cultivation of sandal.

Antibacterial Effect of Bacteriocin Isolated From Lactobacillus Plantarum ATCC 8014 on Postoperative Infection of Mandibular Fracture In Vivo.

OBJECTIVE: The primary objective of this study was to verify the effects of bacteriocin in treatment of postoperative infection of mandibular fracture in vivo. METHODS: Eighty-two mice were inoculated intravenously with staphylococcal suspensions. Bacterial cultures were obtained from implants. Blood samples were collected at 1, 2, 4, 6, and 8 hours after the injection of bacteriocins. RESULTS: Bacteriocins have significant inhibitory effects on Staphylococcus aureus (P < 0.05) and there are significant differences interleukin (IL)-8 and IL-10 in serum (P < 0.05). CONCLUSIONS: Bacteriocin isolated from L plantarum may be one of promising ways to control postoperative infection of mandibular fracture in vivo.