Largest Growth Inhibition Zone Research Articles

Antifungal screening of silver nanoparticles biosynthesized by Aliinostoc oryzae against plant pathogenic fungi

Metallic nanoparticles exhibit exceptional antifungal characteristics and are regarded as a feasible substitute for the control of diverse fungus species. Cyanobacteria have received significant recognition as nanobiofactories across all identified taxa owing to their remarkable ability to assimilate toxins from their environment. Consequently, cyanobacteria-mediated metal nanoparticle synthesis represents an innovative strategy for biological regulation. The present investigation assessed the effectiveness of silver nanoparticles (AgNPs) manufactured using Iranian cyanobacteria, Aliinostoc oryzae, as fungus inhibitors against plant pathogens. For this purpose, the cyanobacterial strain was cultured in BG-110, medium and AgNPs were synthesized by the wet biomass method. The AgNPs were then characterized by UV–visible spectroscopy, DLS, zeta potential, field emission scanning electron microscope (FESEM), transmission electron microscopy (TEM), fourier transform infrared spectroscopy (FT-IR), and X-ray diffraction tests. Afterwards, the antifungal activities of fabricated nanoparticles were tested against fungal strains of Botrytis cinerea, Alternaria alternate, Colletotrichum gloeosporioides, Fusarium oxysporum, Phytophthora capsici, Pythium ultimum, and Rhizopus stolonifera. The results of UV–vis spectrophotometry confirmed the AgNP formation with a color change to dark brown at a wavelength range of 430–432 nm. Morphological examination through the Field Emission Scanning Electron Microscope (FESEM) indicated irregular and spherical shapes. X-ray diffraction (XRD) results showed a cubic crystalline structure with a crystallite size of approximately 20 nm. The zeta potential and electrophoretic mobility of the nanoparticles were −33.67 mV and 0.35 Vs/cm2, respectively. Fourier-transform infrared spectroscopy (FTIR) analysis identified a sharp and intense peak at 538 cm−1, corresponding to the stretching vibration of silver nanoparticle bonds. Based on the antifungal activity results, Pythium ultimum had the largest growth inhibition zone. On the other hand, Colletotrichum gloeosporioides and Alternaria alternate had the smallest inhibition zones. These findings demonstrate the ability to characterize and test AgNPs produced by Iranian cyanobacteria for their antifungal activity.

Antimicrobial Activity of Frankincense (Boswellia sacra) Oil and Smoke against Pathogenic and Airborne Microbes.

As they continuously evolve, plants will remain a renewable source for antimicrobial compounds. Omani frankincense is produced by B. sacra trees and is graded into Hojari, Nejdi, Shazri or Sha'bi. Air can be a source for pathogenic or food spoilage microbes; thus, inactivating airborne microbes is necessary in environments such as food and animal production areas. This study investigated the antimicrobial activity and the chemistry of steam-distilled oils of Hojari and Sha'bi grades. It also analyzed the antimicrobial activity of frankincense smoke and the size of its solid particles. Chemical analysis was performed using gas chromatography mass spectrometry (GC-MS). The antimicrobial activity of the oils against Staphylococcus aureus (NCTC 6571), Bacillus spp., Escherichia coli (NCTC 10418), Pseudomonas aeruginosa (NCTC 10662), Saccharomyces cerevisiae, Candida albicans, Aspergillus flavus, Aspergillus ochraceus, Aspergillus niger, Penicillium citrinum, Alternaria alternata and Fusarium solani was determined using well diffusion and micro-well dilution methods. A microscopic technique was used to determine the size of frankincense smoke solid particles. Microbes were exposed to frankincense smoke to test their susceptibility to the smoke. Hojari and Sha'bi oils were similar in composition and contained monoterpenes and sesquiterpenes. The Hojari and the Sha'bi oils possessed broad spectrum antimicrobial activity. The largest growth inhibition zones were obtained with S. cerevisiae and F. solani. An MIC of 1.56% (v/v) was found with E. coli, S. cerevisiae and F. solani. Frankincense smoke contained fine irregular solid particles with a diameter range of 0.8-2287.4 µm, and thus may pose a health risk to susceptible individuals. The smoke had potent antimicrobial activity against S. aureus, E. coli, and airborne bacteria, yeast and mold, with a maximum inhibition of 100%. It was concluded that Hojari and Sha'bi frankincense oils and smoke had significant antimicrobial activity that can be exploited in controlling human, animal and plant pathogenic microbes.

Indole Derivatives Bearing Imidazole, Benzothiazole-2-Thione or Benzoxazole-2-Thione Moieties-Synthesis, Structure and Evaluation of Their Cytoprotective, Antioxidant, Antibacterial and Fungicidal Activities.

In the search for new bioactive compounds, a methodology based on combining two molecules with biological properties into a new hybrid molecule was used to design and synthesize of a series of ten indole derivatives bearing imidazole, benzothiazole-2-thione, or benzoxazole-2-thione moieties at the C-3 position. The compounds were spectroscopically characterized and tested for their antioxidant, antibacterial, and fungicidal activities. The crystal structures were determined for five of them. Comparison of the closely related structures containing either benzothiazole-2-thione or benzoxazole-2-thione clearly shows that the replacement of -S- and -O- ring atoms modify molecular conformation in the crystal, changes intermolecular interactions, and has a severe impact on biological activity. The results indicate that indole-imidazole derivatives with alkyl substituent exhibit an excellent cytoprotective effect against AAPH-induced oxidative hemolysis and act as effective ferrous ion chelating agents. The indole-imidazole compound with chlorine atoms inhibited the growth of fungal strains: Coriolus versicolor (Cv), Poria placenta (Pp), Coniophora puteana (Cp), and Gloeophyllum trabeum (Gt). The indole-imidazole derivatives showed the highest antibacterial activity, for which the largest growth-inhibition zones were noted in M. luteus and P. fluorescens cultures. The obtained results may be helpful in the development of selective indole derivatives as effective antioxidants and/or antimicrobial agents.

Effect of Liquorice-Extract-Containing Antimicrobial Mouthwash on Helicobacter Pylori: An In Vitro Study

Background: The oral route is one of the main portals for Helicobacter pylori transmission. The elimination of this bacterial species from the oral cavity might be useful in oral health and decreasing infections due to H. pylori. This study aimed to evaluate the effect of a liquorice-extract-containing mouthwash at different concentrations on the proliferation of H. pylori in vitro. Methods: H. pylori bacterial species was cultured, and the isolated strains from the specific culture medium were prepared for the welling procedures. The liquorice (Glycyrrhiza glabra) mouthwash at 12.5% and 25% concentrations was added to the case group wells at 1,1/2,1/4,1/8, and 1/16 dilutions. In the control group, regular daily mouthwash containing cetylpyridinium chloride and sodium fluoride components was used. The growth inhibition zones were analyzed in the study groups. The data were analyzed by SPSS and reported using descriptive statistics (means±standard deviation). Results: In both the mouthwashes containing 25% and 12.5% concentration, the means of growth inhibition zones at 1, 1/2, 1/4, 1/8, and 1/16 dilutions were larger than those in the control group. Further, the largest growth inhibition zone was seen with the undiluted 25% mouthwash. There were no significant differences in the H. pylori growth inhibition zones between 25% and 12.5% mouthwashes (P=0.14). Conclusions: Mouthwashes containing liquorice extracts inhibited the growth of H. pylori more significantly than mouthwash with no liquorice extract. Therefore, it is suggested that liquorice extract-containing mouthwashes be used to prevent H. pylori infections in the oral cavity in clinical studies.

Evaluating the antimicrobial effect of postbiotic extract from Lactobacillus casei on Escherichia coli in commercial sterilized milk

The antimicrobial effect postbiotic extant of Lactobacillus casei was evaluated against Escherichia coli by well propagation method and growth inhibition zone diameter was measured. The selected concentration of the postbiotic extract of Lactobacillus casei was added to milk containing E. coli, followed by evaluating the changes in colony number and pH during storage (1 and 5) days at 4°C then compared with control milk. The largest growth inhibition zone was formed at a concentration of 800 µl/ml against E. coli. Also, the counts of E. coli decreased on days 1 and 5 in the evaluated milk containing postbiotic (p≤ 0.05). The pH of milk containing postbiotic was 6.5-6.8 (p≤ 0.05). The results showed that the postbiotics of L. casei inhibited the growth of E. coli in milk containing.

The Effect of Essential Oils on the Survival of Bifidobacterium in In Vitro Conditions and in Fermented Cream

Essential oils derived from plant materials are a mixture of compounds that exhibit antibacterial properties. Due to their distinct aroma, they also serve as a desirable natural additive for various food products, including dairy products. In this study, the essential oils of lemon peels, clove buds, and juniper berries were obtained by steam distillation and characterized using gas chromatography–mass spectrometry to determine their chemical compositions and effects on the viability of seven Bifidobacterium strains. Furthermore, the effect of essential oils on the viability of Bifidobacterium animalis subsp. lactis Bb-12 was investigated in cream samples during fermentation and after storage for 21 days at 6 °C. The fatty acid composition of fat extracted from essential oils containing sour cream samples and the volatile aroma compound profile of the sour cream samples were also determined chromatographically. Among the 120 compounds identified, monoterpene hydrocarbons were dominant in the essential oils of lemon peels (limonene and γ-terpinene) and juniper berries (sabinene and β-myrcene), while eugenol and eugenol acetate were abundant in the essential oil of clove buds. In addition to these compounds, butanoic and acetic acids were found in the tested sour cream samples. In turn, fat extracted from these samples was rich in saturated fatty acids, mainly palmitic acid. Among the tested strains of the genus Bifidobacterium, B. animalis subsp. lactis Bb-12 was the most sensitive to the essential oils of clove and juniper, as indicated by the larger growth inhibition zones. However, both the concentration and type of essential oils used had no effect on the number of cells of this strain present in the cream samples immediately after fermentation and after its 21-day storage, which suggests that the tested essential oils could be a natural additive to dairy products.

Effect of Magnesium Isotopes on Antibiotic Sensitivity of E. coli

The effect of 25Mg, a magnetic magnesium isotope, on the sensitivity of Escherichia coli K12 TG1 to quinolone/fluoroquinolone (nalidixic acid and ciprofloxacin) and aminoglycoside antibiotics (amikacin and tobramycin) was found. In the case of fluoroquinolones, determination of antibiotic sensitivity by the disc diffusion method revealed the 7‒14% larger growth inhibition zones on the medium with the magnetic magnesium isotope than for the same antibiotics in the variants with 24Mg, 26Mg, or the natural Mg isotope. The effect of the magnetic magnesium isotope 25Mg on the increase in resistance to the quinolones/fluoroquinolones group of antibiotics was observed independently of the determining method: the growth rate of E. coli culture incubated in the medium with 25Mg and ciprofloxacin decreased by 80% compared to the control without antibiotics, while in the variants with 24Mg, 26Mg, and natural Mg the decrease did not exceed 50%. An increase in antibiotic resistance (opposite magnetic isotopic effect) was shown for amikacin, tobramycin, and clindamycin. In the variants with amikacin and clindamycin, the growth inhibition zones of bacteria enriched with 25Mg were 16‒17 and 17‒24% smaller, respectively. An increase in resistance to tobramycin (aminoglycosides) was observed for submerged E. coli cultures growing in the medium with 25Mg: at the antibiotic concentration two times lower than the MIC, the growth rate of E. coli was 86% of the control, while in the variants with nonmagnetic isotopes or natural magnesium it decreased by 40‒50%. The mechanisms of magnetic isotopic effects of 25Mg are discussed: its effect on the enzymatic activity of Mg-dependent enzymes involved in protection of the cells from the action of antibiotics.

Smear Layer Removal from Root Canal Dentin and Antimicrobial Effect of Citric Acid-modified Chlorhexidine.

Objective:To study the effectiveness of various concentrations of citric acid (CA) added to 2% chlorhexidine (CHX) on smear layer removal from the root canal wall and antimicrobial efficacy against Enterococcus faecalis (E. faecalis) and Candida albicans (C. albicans).Methods:Fifty-three single-rooted mandibular premolars were decoronate and the root canals underwent mechanical instrumentation using MTwo rotary files to size 40/0.06. The samples were then randomly divided into 5 groups according to the root canal irrigants to be used: 17% ethylenediaminetetraacetic acid (EDTA), 2% CHX, 1%, 6%, and 10% citric acid-modified 2% chlorhexidine (CAmCHX). Three teeth irrigated with phosphate-buffered saline (PBS) were used as a negative control. The smear layer removal effectiveness was evaluated under scanning electron microscopy (SEM). Images were randomly taken at the apical, middle, and coronal third level. Statistical analysis was performed using Kruskal-Wallis and Mann-Whitney U tests. Disc diffusion and direct exposure tests were performed along with three additional control groups consisting of 1%, 6%, and 10% CA groups to assess and compare the antimicrobial efficacy of irrigants against E. faecalis and C. albicans. Statistical analysis was conducted using one-way ANOVA and Dunnett’s T3 tests.Results:Smear layer removal effectiveness in 17% EDTA group and 6% and 10% CAmCHX groups were not significantly different in the coronal and apical third of the root canal (P>0.05), however at the middle third of the root canal, the 10% CAmCHX group had significantly less remaining smear layer than all of the other experimental groups (P<0.05). There was significantly more smear layer remnant in the CHX group (P<0.01). For antimicrobial efficacy, the largest growth inhibition zone against E. faecalis was recorded in the 10% CAmCHX group (P<0.05). For planktonic E. faecalis, 1%, 6%, and 10% CAmCHX demonstrated an insignificant difference in antimicrobial efficacy compared to CHX (P>0.05). CA demonstrated no antifungal effect against C. albicans. Whereas, 6% and 10% CAmCHX resulted in the largest growth inhibition zone. Also, adding CA to CHX resulted in an insignificant difference in antifungal effect against planktonic C. albicans compared to CHX (P>0.05).Conclusion:When CA was added into CHX, the mixed irrigant demonstrated smear layer removal ability. Additionally, its antimicrobial effect remained the same.

The effectiveness of white turmeric (Curcuma zedoaria) extracts as root canal irrigation alternative material on Streptococcus viridans

Irrigation is one of the important principles of triad endodontic to eradicate microorganisms in root canal infections. The rhizomes of white turmeric (Curcuma zedoaria) contain compounds that have antibacterial activity and has a potential to be used as an alternative for irrigation solution. The study was done to evaluated the antimicrobial activity of white turmeric extracts againts Streptococcus viridans. This experimental in vitro study used four extracts of white turmeric with various concentrations (100%, 50%, 25%, 12.5%) as tested groups, 2% Chlorhexidine as positive control and distilled water as negative control group. Solid BHI medium containing Streptococcus viridans was perforated with a cork borer and dropped by 5 mL solution according to each group. The inhibition zone diameter was measured to evaluate antibacterial efficacy. Data were analyzed by One Way ANOVA and continued by Post-hoc Bonferroni. The results showed that all groups had significant differences. The largest growth inhibition zone was 100% white turmeric extracts group and had strong antibacterial effect, followed by 50% and 2% chlorhexidine, while 25% and 12.5% extracts had moderate antibacterial effect. Based on the results of this study it can be concluded that white turmeric extracts can inhibit the growth of Streptococcus viridans.

Perbandingan Aktivitas Antibakteri Ekstrak Curcuma zedoaria dan Bahan Irigasi Natrium Hipoklorit 2.5% terhadap Enterococcus faecalis

Sodium hypochlorite (NaOCl) is a powerful disinfectant used in root canal therapy, yet it has some disadvantages. There are growing interests of using extracts of natural materials containing antibacterial secondary metabolite compounds as an alternative of irrigation solution. Aim, to compare the antibacterial activity of white turmeric extracts and 2,5% sodium hypochlorite irrigant against Enterococcus faecalis. Methods, this was a quasi experimental study. White turmeric extracts at the concentrations of 75%, 50%, 25% and 10% were used as experimental groups, while 2,5% NaOCl and distilled water were the control groups. Suspensions of Enterococcus faecalis were prepared to a 0.5 Mc Farland standard and applied onto petri plates containing Muller Hinton Agar. Six wells were created in each plate, and filled with 20 mL of the test solution. Plates were incubated at 37 ° C for 24 hours. The antibacterial activity was evaluated by measuring the clear zone around the well. Data were analyzed by Kruskall Wallis and continued by Mann U Whitney. Results, the largest growth inhibition zones were produced when the test bacteria were in contact with 2,5% NaOCl (15,0233 mm). White turmeric extract 75% concentration had weak antibacterial effect, while white turmeric extract 50%, 25%, 10% concentration, and distilled water did not has antibacterial properties against Enterococcus faecalis. Conclusion, white turmeric extract 75% concentration can inhibit the growth of Enterococcus faecalis with weak antibacterial activity.

In Vitro Evaluation of Antimicrobial Activity of Alimentary Canal Extracts from the Red Palm Weevil, Rhynchophorus ferrugineus Olivier Larvae.

The invasive red palm weevil, Rhynchophorus ferrugineus Olivier (Coleoptera: Curculionidae), is considered one of the world's most devastating insect pests to palm trees. It was observed that larvae of this pest are able to inhibit microbial growth on the rearing media when they start feeding and this observation has led us to study the effect of red palm weevils on various microbial species. The antimicrobial effect of extracts from different parts of the alimentary canal on Gram positive bacteria (Enterococcus faecalis and Staphylococcus aureus), Gram negative bacteria (Escherichia coli and Klebsiella spp.), Candida albicans, and Penicillium sp. was tested using the agar well diffusion method. All extracts inhibited the tested microbial species. Foregut extracts had the greatest zones of growth inhibition. Enterococcus faecalis, Staphylococcus aureus, and Penicillium sp. were significantly sensitive to the extracts and had the largest growth inhibition zones. It is concluded that the gut extracts contain potent antimicrobial activity and may provide a new source of antimicrobial peptides.

First ever report on the antimicrobial activities of some selected mangrove halophytes of Sundarban against milk spoilage microflora

The study was governed by the objective of investigating the antimicrobial effects of mangrove leaf extracts. The fresh and dried leaf extracts from Avicennia marina (Forssk.) Vierh., Avicennia officinalis L., Aegiceras corniculatum (L.) Blanco, Aegialitis rotundifolia Roxb., Acanthus ilicifolius L, Lumnitzera racemosa Willd., Excoecaria agallocha L. and Sonneratia apetala Buch-Ham. were found to have inhibitory effects on the milk spoilage microflora obtained from curd sample. Methanol and Acetone were used as extraction solvents and in comparison, extracts by acetone were observed to suppress the microbial growth to lesser extents. Leaf extracts of A. marina, A. officinalis L. racemosa and A. rotundifolia were able to exert relatively greater inhibitory effect on the milk spoilage microbial broth than others, although all the species expressed some degree of suppression. Interestingly A. rotundifolia, S. apetala, L. racemosa and E. agallocha demonstrated greater efficiency in formation of larger growth inhibition zones on the petri plates. The extracts obtained from dry leaves produced greater adverse effects of the microbes than the raw leaf extracts. The data generated were analyzed with the help of 'ANOVA: Single factor' and 'F-test: Two sample for variance' and data sets were of statistical significance at 0.05 level of significance as null hypothesis was rejected.

Evaluation the antibacterial effects of Echinophora platyloba extracts against some Salmonella species.

IntroductionSalmonellosis, which is caused by nontyphoid salmonella bacteria, is one of the most common foodborne diseases, and it causes gastrointestinal infections worldwide, most of which are limited gastroenteritis that requires antimicrobial treatment. The aim of this study was to investigate the effects of echinophora platyloba extract on inhibiting the growth of Salmonella typhi, Salmonella enteritidis, and salmonella choleraesuis.MethodsEchinophora Platyloba extract was collected in the East Azarbaijan Province in Iran in June 2015. Weeds, infected plants, and dried roots were separated and removed. After drying and grinding the plant, 100 grams of powder were weighed, and the extraction of the plant was carried out by percolation. This study tested the Minimum Inhibitory Concentration (MIC) by the broth micro dilution method and Minimum Bactericidal Concentration (MBC). All of the data were analyzed by SPSS statistical software, version 22.0. One-Way ANOVA and the Duncan test were used to compare the effect of various concentrations of the extract on each type of bacteria.ResultsOur results indicated that, in 250 mg/ml of extracts discs, the largest growth inhibition zones were formed, and they were 26.11 ± 1.16, 21.23 ± 0.89, and 19.65 ± 0.60 in S. enteritidis, S. typhi, and S. choleraesuis groups, respectively. The statistical results indicated that, in each type of bacteria, there was a statistical difference (p < 0.01) between the various concentrations of the extracts and the chloramphenicol discs. Also, it was indicated that this extract at a concentration of 150 mg/ml had a germicidal effect on S. enteritidis and S. typhi bacteria and that 250 mg/ml had a bactericidal effect on S. choleraesuis.ConclusionThe results of this study indicated that E. platyloba extract has potential effects as antimicrobial agents.

Xanthomonas campestris pv. viticola on grapevine cutting tools and water: survival and disinfection.

Bacterial canker (Xanthomonas campestris pv. viticola) (Xcv) is the most important disease of grapevine in northeast of Brazil. The survival of Xcv2Rif was evaluated from 0 to 42 h following the dipping of the harvest shears in a pathogen suspension. An in vitro test of Xcv sensitivity to sanitizing agents and initial tests on shears were performed with dodecyl dimethyl ammonium chloride (1,140 ppm), benzalkonium chloride (245 ppm), sodium dichloroisocyanurate (16.2 ppm), sodium hypochlorite (20,000 ppm), calcium hypochlorite (130 ppm), calcium oxychloride (97,500 ppm) and chlorine dioxide (41 ppm). The ability of dodecyl dimethyl ammonium chloride (1,140 ppm) and sodium hypochlorite (20,000 ppm) to disinfect shears was tested with 50 sequential cuts on vine leaves. The maintenance of the efficacy of the sanitizing agents was tested between 0 and 8 h following solution preparation. The ability of five sanitizing agents to disinfect Xcv-contaminated water was also tested. Xcv survived for 24 h on harvest shears. Sodium hypochlorite and dodecyl dimethyl ammonium chloride presented the largest growth inhibition zones to four Xcv isolates and were 100% effective in disinfecting contaminated harvest shears. These two sanitizing agents maintained their efficacy for 8 h. Xcv was spread by contaminated harvest shears until the 24th cut, in average. Water disinfection was successfully achieved with dodecyl dimethyl ammonium chloride (570 ppm), sodium hypochlorite (5,000 ppm) and benzalkonium chloride (122.5 ppm).

Comparative study of the antimicrobial efficacy of chlorhexidine gel, chlorhexidine solution and sodium hypochlorite as endodontic irrigants

The purpose of this study was to assess the in vitro the antimicrobial efficacy of chlorhexidine gluconate gel as an endodontic auxiliary chemical substance compared to sodium hypochlorite (NaOCl) and chlorhexidine gluconate solution. The antimicrobial efficacy of the tested substances was evaluated using the agar diffusion test. The growth inhibition zones produced by 0.2%, 1% and 2% chlorhexidine gel were evaluated against 5 facultative anaerobic bacteria and 4 pigmented Gram-negative anaerobes, and compared to the results obtained by NaOCl and chlorhexidine solution. The largest growth inhibition zones were produced when the test bacteria were in contact with 2% chlorhexidine gluconate gel (11.79 mm), being significantly different (p<0.05) from the growth inhibition zones produced by all NaOCl concentrations, including 5.25% (9.54 mm). However, there was no statistically significant difference (p>0.05) between the growth inhibition zones obtained with equal concentrations of chlorhexidine solution and gel. The results of this study indicate that, as far as its antimicrobial properties are concerned, chlorhexidine gel has a great potential to be used as an endodontic auxiliary chemical substance.

Stimulation of nodulation and plant growth of chickpea ( Cicer arietinum L . ) by Pseudomonas spp. antagonistic to fungal pathogens

Two strains of Pseudomonas MRS23 and CRP55b showed antagonistic activity towards the pathogenic fungi Aspergillus sp., Fusarium oxysporum f. sp. ciceri, Pythium aphanidermatum and Rhizoctonia solani under culture conditions. Larger growth inhibition zones were obtained on nutrient agar (NA) and King's B media in comparison to potato dextrose agar and pigment production media. Both the strains produced siderophore in agar plates as well as in liquid cultures. Fungal inhibition zones were reduced in size and abolished in iron-supplemented NA medium by Pseudomonas strains MRS23 and CRP55b, respectively, indicating that some other metabolites along with siderophores are involved in growth inhibition of fungi by strain MRS23, whereas CRP55b produced only siderophores. Only Pseudomonas strain MRS23 was found to produce hydrocyanic acid (HCN). Seed bacterization with Pseudomonas strains of two chickpea (Cicer arietinum L.) cultivars, H8618 and C235, showed root-stunting effects at 5 days, whereas this inhibitory effect was overcome at 10 days of seedling growth in cv. H8618. Coinoculation of chickpea with Pseudomonas strains MRS23 and CRP55b, and Mesorhizobium sp. Cicer strain Ca181 resulted in the formation of 68.2–115.4% more nodules at 80 and 100 days after planting as compared to single inoculation with the Mesorhizobium strain under sterile conditions. The shoot dry weight ratios of coinoculated treatments at different stages of plant growth varied from 1.18 to 1.35 times that of Mesorhizobium-inoculated and 3.25 to 4.06 times those in uninoculated controls. The plant N contents were also increased significantly on coinoculation. Coinoculation effects of HCN-producing strain MRS23 were significantly lower than those of non-HCN-producing strain CRP55b in terms of shoot dry weight and shoot N. The results demonstrated the potential benefits of using rhizosphere bacteria as coinocula in nodule promotion and plant growth in chickpea.