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In recent years, bio-healing based on microbial induced carbonate precipitation in cracks has been widely exploited to improve concrete properties and thus increase its durability. In this context, the present study aims to explore the possibility of using nine bacterial isolates as biohealing agent of cementitious materials; these bacteria (coded B1 to B8) were obtained from the three different rocky sites, i.e., 795 L1 (limestone rock site), 795 L2 (ordinary soil site), and 812 (clayey site); situated in Oulad Rahmoun (Constantine-Algeria). The primary identification showed that eight isolates belonged to a Bacillus genus, and one isolate B8 developed particularly morphological characterized by branched and septate hyphae. The isolates B4 and B8 were selected for their ability to produce calcium carbonate in precipitate calcium (PC) liquid and solid media after five days of incubation. The addition of urea in PC liquid media accelerated the formation of calcite which appeared after 3 days of incubation. The growth curve of both selected isolates on LB liquid medium showed that B8 was characterized by a long exponential growth phase (up to 72 hours) compared to B4 which had an exponential phase up to 48 hours, which could explain the largest amount of calcite precipitate observed in the case of B8 cultivated in PC liquid medium. Results of the bio-healing experiment carried on cementitious batches showed that a beginning of a slight repair of the cracks from the 11th day was only observed in the case of the bacterium B8 but the bio-healing capacity was absent in the control. This bio-healing agent was identified as Micromonospora echinospora (NCBI-NO139612), according to N-Blast of 16S-DNA sequence. In conclusion, the present study is the first to isolate M. echinospora species from rocky sites; and to describe it as an efficient bacterial agent in concrete bio-healing applications.

Tetraclinis articulata is a forest plant species that is widely used in North African folk medicine due to its immense bioactive potential. The objective of the present study was to characterize flavonoids present in butanolic extract of aerial part of T. articulata (TABE) and to test its antibacterial synergistic effect, anticoagulant and antioxidant properties. The analysis of the TABE by colorimetric tests and TLC revealed the presence of flavonoids. The dosage showed that the proportions of total flavonoids and flavonols were 19.25 ± 0.07 and 13.6 ± 1.6 mg QE/g DW, respectively. Besides, the greatest antibacterial activity of the extract was shown against S. aureus. In contrast no effect was observed against E. coli. Furthermore, the most synergistic potential inhibitory effect was noted in the case of E. coli, when the extract was combined with penicillin. In addition, the MICs was determined used microdilution method, the values obtained were ranged from 2.5 to 20 mg/ml. Moreover, the in vitro anticoagulant activity was assessed by PT and KCT tests. The results showed interesting anticoagulant activity, with KCT value of 55.4 s which is superior to that obtained by the anticoagulant drug –Lovenox- (39.37s). The antioxidant activity was evaluated in vitro using DPPH• method. The result expressed in terms of IC50 was found to be 0.04 mg/ml. To conclude, the TABE constitutes a valuable source of anticoagulant, antioxidant and antibacterial synergism metabolites, which makes it a potential candidate to isolate responsible flavonoids and to develop novel pharmaceutical formulations.

Among the postharvest pathogens of apple fruit, Penicillium expansum (P.expansum) is considered to be one of the most common fungal pathogens worldwide. It is the causal agent of blue mold decay; the main serious economically disease of apple fruits, and the main producer of patulin (PAT). The principal objective of this work was to evaluate the aggressiveness and the PAT production of three isolated strains from apples produced in the East of Algeria. These strains were isolated then screened for their inhibitory activity against Escherichia coli and Bacillus subtilis (18 mm and 18 mm for S7; 10 mm and 11mm for S3), as well as their ability to cause blue rot (S4). The three strains S7, S3, and S4 (MN904448, MT023795 and MN904449, respectively) were identified as P. expansum by ITS1, ITS4, and β-tubulin gene sequences analysis. The in vitro ability to produce PAT was confirmed by Gas chromatography-mass spectrometry of strains’ crude extracts cul-tured on YES (Yeast-Extract-Sucrose) medium. Indeed, these strains exhibited a great capacity to cause blue mold decay for all tested apples (26 to 52 mm lesion diameter), after nine days of incubation at 25°C. Apples rotten area analysis that was performed by UPLC analysis revealed that these three strains were able to produce PAT at different concentrations ranging from 0.57 to 469 μg/mL. Thus, these strains constitute a risk to consumer health because these amounts exceed the permissive level of PAT.

Brown rot disease of Canino apricots and FlordaPrince peaches is a major serious decay disease during cold storage in Egypt and worldwide, Infection of stone fruits may occur during blooming until harvest harvest which cause decay during cold storage. The effect of fungicide safe alternatives, (Chemical salts and Inducing resistance). The effect of fungicide safe alternatives, i.e. sodium bicarbonate, calcium chloride, potassium sorbate, potassium silicate,boric acid and salicylic acid, on growth of Monilinia laxa M. fructigena and Monilinia sp. as major pathogens on apricots and peaches ,was investigated at different concentrations ranged from 1000 ppm to 5000 ppm amended in PDA in vitro. Sodium bicarbonate at 1000 ppm completely suppressed the growth of the three isolates of Monilinia spp., Calcium chloride at 1000 ppm to 5000 ppm, did not show any suppression of M. laxa or Monilinia sp., while it suppressed M. fructigena when used at ≥4000 ppm. Potassium silicate did not show considerable effectiveness against different tested isolates of Monilinia spp. IC50 values (chemical concentration that reduce fungal growth to 50%) of sodium bicarbonate, potassium sorbate and salicylic acid on M. fructigena were less than 1000 ppm. On M. laxa, only sodium bicarbonate showed IC50 less than 1000 ppm, while the IC50 values of potassium sorbate and boric acid were less than 2000 ppm. Regarding Monilinia sp. sodium bicarbonate and potassium sorbate IC50 values were less than 1000 ppm. Generally, sodium bicarbonate, potassium sorbate and salicylic acid showed IC50 values less than 1000 ppm, 2000 ppm, and 3000 ppm, respectively. These salts and inducers at 3000 ppm, were used as three preharvest sprays starting at growth stage no. 64 and then repeated twice at 10 days intervals in orchard located at Qualyubia and Ismailia, during seasons 2015 and 2016. These salts and acids were also adopted at 3000 ppm on naturally infected or artificially inoculated fruits after harvest at growth stage no. 81 during season 2016. Sodium bicarbonate, calcium chloride, potassium sorbate and boric acid were the most effective treatments to control brown rot disease on apricots and peaches during cold storage at 0oC and 90% RH for 15 days and 30 days, either these chemicals were sprayed preharvest or adopted after harvest. These treatments maintained fruit quality regarding firmness and acidity.

Еssеntial oils (ЕOs) from cinnamon (Cinnamon zylanicum), clovе (Syzygium aromaticum) camphor (Еucalyptus globulus), and rockеt (Еruca sativa), wеrе еvaluatеd for thеir botryocidal еffеct. In-vitro, Botrytis cinеrеa was еxposеd to 4 diffеrеnt concеntrations of ЕOs, using thrее diffеrеnt tеchniquеs, i.е. amеndеd mеdium, vapourisation, and volatilising. Cinnamon and clovе ЕOs wеrе thе highеst tеstеd concеntrations found to bе thе most еffеctivе in all tеchniquеs which complеtеly inhibitеd 100% of radial growth for B. cinеrеa in vitro. A post-harvеst trial to control grеy mould on grapе bunchеs of Flamе sееdlеss and Supеrior sееdlеss cvs. were conductеd using cinnamon and clovе oils in sеasons 2014 and 2015. Both of the two ЕOs wеrе usеd at concеntrations of 25, 50 and 100 µL./L-1air v/v, еxposеd as vapour trеatmеnt significantly supprеssеd grеy mould during thе cold-storagе. Thеrе was not a significancе diffеrеncеs obsеrvеd among both ЕOs trеatmеnts. Howеvеr, cinnamon at 100 µL.1L-1air v/v was thе most еffеctivе trеatmеnt to control grеy mould of both grapе cultivars

In this study, chemical and bio-control agents were evaluated for their efficiency to control of citrus fruit-rot disease caused Alternaria citri (K2) both, in vitro and in vivo trials. The most effective fungicides were score, montro and Iprodione compared with other fungicides depend on Ec50 and Ec90. While, the fungicide Pyraclostrobine had moderate effect on linear growth of A. citri. Meanwhile, the Coprax, Coprareekh and Azoxystrobine were the least effective fungicide at Ec90. Trichoderma harzianum and Bacillus subtilis tested showed antagonistic action effect to a highly pathogenic isolate of Alternaria citri, with different degrees of inhibition. T. harzianum was the most effective compared with B. subtilis, in vitro trials. Also, all fungicides were evaluated on incidence of citrus fruit rot disease in vivo trials. The disease incidence was reduced, but with different degrees. In addition, using T. harzianum, B. subtilis, B. megaterium (Bio-ARC) and Trichoderma album (Bio-Zeid) decreased incidence of citrus fruit rot disease. On the other side, T. harzianum showed the highest suppressive effect against citrus fruit rot pathogen. Generally, all tested fungicides and bio-agents were effective against the causal fungus in vitro and in vivo trials, but with different degrees.

Calycotome spinosa (L.) Link is one of the important plants in traditional medicine especially in Algeria. The present work deals with the phytochemical screening, the flavonoids extraction from leaves and flowers of this plant, the quantification of total polyphenols and flavonoids, as well as the evaluation of antioxidant and antimicrobial properties of ethyl acetate and n-butanol fractions. While, the rest, interacted with its phenolics identification. The results of preliminary phytochemical screening showed that C. spinosa contained various metabolites: Polyphenols, flavonoids, alkaloids, saponins etc. In addition, the findings of polyphenols determination using Folin Ciocalteu was high in all the fractions: 107.75±0.41 and 64.24±1.81 mg gallic acid equivalents/g extract for leaves ethyl acetate and n-butanol respectively and 81.45±0.6 and 96.06±2.72 mg gallic acid equivalents/g extract for flowers ethyl acetate and n-butanol successively. Conversely, the flavonoids content in the four fractions by AlCl3 was less important than polyphenols. Moreover, the obtained fractions were evaluated for their antioxidant capacity using DPPH assay. Besides, the obtained result revealed that Ethyl acetate and n-butanol fractions of leaves exerted very high antioxidant activities with IC50 equal to 45.25±1.8 and 52.80±2.05 µg/mL, respectively compared with flowers. Furthermore, the antimicrobial activity of those fractions against many microbial strains have also been investigated using the disc diffusion method; the leaves ethyl acetate fraction showed the highest activity against Acinetobacter baumannii with a zone inhibition diameter equal to 22±0.06 mm. Additionally, high-performance liquid chromatography/diode-array detector (HPLC/DAD) analysis performed with C. spinosa fractions revealed the richness of plant in many phenolic compounds. Key words: Calycotome spinosa (L.) Link, medicinal plant, phenolics and flavonoids content, antioxidant activity, antimicrobial potential, high-performance liquid chromatography/diode-array detector (HPLC/DAD).

Several Bacillus strains were isolated from “Ouled Yelass” hot spring soil, located in Setif city (Eastern Algeria). Three isolates of them coded (4RH), (14 RH), and (Set-oxy), were screened for their ability to inhibit the growth of some phytopathogenic fungi, such as Fusarium oxysporium, Botrytis cinerea, Aspergillus niger, Cladosporium cucumerinium and Alternaria alternata. The molecular identification of the strain (4RH) based on the 16S-DNA and gyrase-A genes sequences analysis, showed that it is closely related (99.9%) to the Bacillus amyloliquefaciens species. This bacterium was characterized by a high sporulation yield reaching 22±0.86 × 108 spores/ml and had important inhibition rates up to 80 and 70%, against F. oxysporium and B. cinerea, respectively. The bacterium (4RH) was able to produce cell wall degrading enzymes of cellulase and protease, in contrast to chitinase activity which was negative. Furthermore, it produced the three lipopeptides families, which are, iturins A (C14; C15), fengycin A (C14, C15, C16, C17, and C18), and surfactin (C12, C13, C14, C15, C16). Interestingly, LC-MS profiles of 80% acetonitrile fengycin extract of the (4RH) strain, showed the presence of some new molecular ions (MH+) with masses different, but near to conventional fengycin variants, which correspond to new variants described for the first time in this work. The isolate (4RH) produced 5 µg/ml of the phytohormone (IAA), on TGE medium and siderophores with more than 10 mm of yellow-orange zones, on CAS medium. To conclude, B. amyloliquefaciens (4RH) strain possessed interesting biocontrol and biofertilization characteristics, in vitro, in addition to its high sporulation yield, which make it a potential agent for future biopesticide that could be efficient in the integrate pest management and organic agricultural production systems. Key words: Bacillus, biocontrol, biofertilization, plant protection, hot spring, lipopeptides.

The aim of this study is to explore the impact of Lycium halimifolium Mill leaves extracts on mycotoxin B1 production in vitro, as well as the inhibitor effect of the aflatoxin B1 synthesis by Aspergillus flavus strain. The strain was isolated, identified (gi |146746162 | EF409803.1.) and positively tested for the production of Aflatoxin B1. The antimycotoxinogenesis effect was investigated using L. halimifolium Mill leaves consisting of butanol and ethyl acetate fractions. Indeed, the fractions were tested to stop the secretion of aflatoxin B1 by A. flavus in submerged culture (YES), simultaneously. The growth of the strain was evaluated as biomass response. The antimycotoxinogenesis activity showed that the two fractions: ethyl acetate and butanol of L. halimifolium Mill leaves were able to inhibit significantly the synthesis of mycotoxin AFB1. Thus, the secretion inhibition percentage was calculated in comparison with the control, using HPLC-PDA technique, and estimated at 96.83% for butanolic fraction and 94.99% for ethyl acetate fraction. To verify its correlation with biomass, the growth inhibition percentage was also estimated. The results showed that the dry weight concentration under butanolic and ethyl acetate fractions was 1.6 and 2 g/l, respectively, corresponding to 65.22 and 56.53% of inhibition growth percentage. Key words: Aflatoxin B1, antimycotoxinogenesis activity, high performance liquid chromatography coupled with photodiode array detector (HPLC-PDA), natural extract.

Synthesis, characterization, corrosion inhibition as well as antimicrobial activity of the coordination compounds {Co(bbms)Cl2}, {Zn(bbms)Cl2}, {Co(btmb)Cl2} and {Zn(btmb)Cl2} containing benzimidazole thioether have been described. Co(bbms) and Zn(bbms) as well as Co(btmb) and Zn(btmb) are isostructural with space group Pbca and P21 respectively. The coordination polyhedron around the metal center for all complexes may be described as a quasi-regular tetragonal geometry. The corrosion inhibition study of these complexes for steel in 0.5 M H2SO4 medium has been investigated using potentiodynamic polarization and EIS techniques. These later show the corrosion inhibition ability of the prepared complexes for steel in acid medium. A new procedure has been developed for antimicrobial assay using a solid tablet of the corresponding complexes. These later show moderate to significant antimicrobial activities against: Pseudomonas syringae, Staphylococcus aureus and Pichia caribbica. DFT/BP86 calculations have been carried out on the neutral complexes and on the monoanionic of (1) and (3) forms of singlet and triplet species. The optimized structures reproduce those observed experimentally, while the reduced ones undergo remarkable geometrical parameters variations.

The growth kinetics and modeling of ethanol production from inulin by Pichia caribbica (KC977491) were studied in a batch system. Unstructured models were proposed using the logistic equation for growth, the Luedeking-Piret equation for ethanol production and modified Leudeking-Piret model for substrate consumption. Kinetic parameters (X0, μm, m, n, p and q) were determined by nonlinear regression, using Levenberg-Marquart method implemented in a Mathcad program. Since the production of ethanol was associated with P. caribbica cell growth, a good agreement between model predictions and experimental data was obtained. Indeed, significant R2 values of 0.91, 0.96, and 0.95 were observed for biomass, ethanol production and substrate consumption, respectively. Furthermore, analysis of variance (ANOVA) was also used to validate the proposed models. According to the obtained results, the predicted kinetic values and experimental data agreed well . Finally, it is possible to predict the development of P. caribbica using these models. Key words : Pichia caribbica, inulin, bioethanol, numerical simulation.

The soil bacteria, CWBI-B1567 and CWBI-B1568, isolated from arid regions and identified as Bacillus subtilis (accession number KC341751) and Bacillus mojavensis (accession number KC341749) respectively, were screened and evaluated for their antifungal activity against Candida albicans, one of the most important human fungal pathogens. In vitro assay with the antagonists and their cell-free culture supernatants on agar plates showed that the two Bacillus strains effectively inhibited growth of the yeast. The capacity of these Bacillus strains to produce the cell-wall degrading enzymes was further studied. B. subtilis and B. mojavensis are able to produce cellulase and protease, but not chitinase. Bioactive molecules were produced by B. subtilis CWBI-B1567 and B. mojavensis CWBI-B1568 in a liquid culture medium optimised for lipopeptide production. The antifungal activity was equally demonstrated by testing the resulting supernatants and lipopeptide-enriched extracts. The electro-spray mass spectrometry coupled to liquid chromatography (ESI-LC-MS) analysis showed that both the B. subtilis and the B. mojavensis produced surfactin and iturin. However the fengycin group was produced only by B. mojavensis. Through this study, we have demonstrated that B. subtilis and B. mojavensis have a strong antifungal activity especially against C. albicans. This growth inhibition is probably due to the production of cell-wall degrading enzymes and different families of lipopeptide including iturins, fengycins and surfactins. Key words: Bacillus subtilis CWBI-B1567, Bacillus mojavensis CWBI-B1568, antifungal activity, Candida albicans, lipopeptides, electro-spray mass spectrometry coupled to liquid chromatography (ESI-LC-MS), arid regions.

This report is to our knowledge the first to study plant growth promotion and biocontrol characteristics of Bacillus isolates from extreme environments of Eastern Algeria. Seven isolates of 14 (50 %) were screened for their ability to inhibit growth of some phytopathogenic fungi on PDA and some roots exudates. The bacteria identification based on 16S r-RNA and gyrase-A gene sequence analysis showed that 71 % of the screened isolates belonged to Bacillus amyloliquefaciens and the rest were closely related to B. atrophaeus and B. mojavensis. Most of them had high spore yields (22 × 10(8)-27 × 10(8) spores/ml). They produced protease and cellulase cell wall-degrading enzymes while the chitinase activity was only observed in the B. atrophaeus (6SEL). A wide variety of lipopeptides homologous was detected by liquid chromatography-electrospray ionization-mass spectrometry analysis. Interestingly, some additional peaks with new masses were characterized, which may correspond to new fengycin classes. The isolates produced siderophores and indole-3- acetic acid phytohormone. The greenhouse experiment using a naturally infested soil with Sclerotonia sclerotiorum showed that the B. atrophaeus (6SEL) significantly increased the size of the chickpea plants and reduced the stem rot disease (P < 0.05). These results suggest that these isolates may be used further as bio-inoculants to improve crop systems.

Tomato, Solanum lycopersicum is one of the most important vegetable crops consumed in Algeria. Tomato crops are often infected by Alternaria alternata, which causes early blight disease. Chemical pesticides are intensively used to protect this plant, which lead to environmental pollution that might endanger animal and human health. The main objective of this study is to select potential biocontrol agents from arid soil as an alternative to chemical products. The phytopathogenic fungus which was isolated from infested tomato leaves, stems and fruits cultured in Constantine-Algeria, was identified as Alternaria cf. alternata. Thirty five bacteria isolates were obtained from arid soil in the south of Algeria. Three of the isolates inhibited the growth of A. alternata. However, the most potent isolate, E1B3 reached a 75% inhibition rate. The molecular identification of this isolate showed that it was closely related to Bacillus mojavensis (KC977492). This strain does not produce chitinase, but does produce lipase, protease and lipopeptides. The interaction between A. alternata and B. mojavensis was investigated for the first time in this work by flow cytometric analysis. In conclusion, B. mojavensis strain was antagonistic to A. alternata which could possibly be exploited as a biopesticide in tomato crops management. Key words: Tomato, Bacillus mojavensis, early blight, Alternaria alternata, flow cytometry.

Lactic bacteria are used in fermentation and food bio‐preservation through their production of organic acids and other antimicrobial substances like bacteriocins which restrain certain fungal strains. The main objective of this study is the isolation of Lactobacillus strains from curdled milk samples, in order, to inhibit, in vitro, mycotoxins production by Aspergilus flavus. Six bacterial isolates were obtained from curdled milk commercialized in the region of Constantine. Among them, one isolate coded (B6) had a significant inhibitory effect against A. flavus (the diameter of colony not exceeding 1.5 cm after 72 hr of incubation at 28°C). This isolate (B6), was identified morphologically and biochemically. The obtained results showed that this bacterial isolate belongs Lactobacillus genus. In addition, its antimycotoxinogen activity had been confirmed using some test bacteria, such as E. coli, Staphylococcus aureus, Klebsiella sp., and Pseudomenas syringae. PRACTICAL APPLICATIONS: This paper describes the isolation of lactic bacteria strains from Algerian curdled milk and the study of their antifungal and antimycotoxinogen activity. The method used to test the effect of lactic bacteria strains against toxigenic fungi was not previously exploited. The main objectives were to: (a) Isolate and select the lactic bacteria from curdled milk; (b) Isolate and identify the toxigenic fungi; (c) Select bacterial isolates for antifungal effect against toxigenic fungi; (d) Study of their antimycotoxinogen activity, in vitro.

Several nurseries of olives in Fayoum and Giza were surveyed for root rot incidence during early summer of 2003. In Fayoum, root rot incidence reached 53% while in Giza, disease incidence was 44%. Disease symptoms consist of partial wilting, leaves browning and twig dieback, which was associated with severe root rot and basal stem cankers and followed, in most cases, by plant decline and death. The most frequently isolated fungi from rotted roots were Fusarium oxysporum, F. solani, F. moniliforme, Rhizoctonia solani, Sclerotium rolfsii, Cylindrocarpon sp. and Alternaria alternata. Isolation frequency of different fungi varied among olive cultivars. Generally, Fusarium spp. were the most frequently isolated pathogens and Fusarium oxysporum was the most frequent (35.5%) on all cultivars followed by F. solani (19.3%) R. solani (16.1%). Meanwhile, S. rolfsii, F. moniliforme, Cylindrocarpon sp. and A. alternata occurred at lowfrequencies. Pathogenicity tests showed that all tested isolates caused varied degrees of root rot symptoms on olive transplants, cvs. Manzanillo and Picual. Fusarium oxysporum, F. solani and R. solani caused the highest root rot incidence and severity on both cultivars. There was a positive correlation between disease severity on roots and severity of foliar symptoms. All evaluated olive cultivars were susceptible or extremely susceptible to fungal pathogens. All cultivars showed high disease severity with root rots, especially in response to infection by F. solani, F. oxysporum and S. rolfsii. However, the least foliar symptoms were recorded on cultivar Coratina. Application of two commercial biological control products (Rhizo-Plus and Trichoderma 2000) to soil, 24h before planting olive cuttings in the nursery, significantly reduced incidence of root rot on transplants of cultivars Manzanillo and Picual, up to 28 weeks after planting

This work aims to study the production of the biomass of S. cerevisiae on an optimized medium using date extract as the only carbon source in order to obtain a good yield of the biomass. The biomass production was carried out according to the central composite experimental design (CCD) as a response surface methodology using Minitab 16 software. Indeed, under optimal biomass production conditions, temperature (32.9 °C), pH (5.35) and the total reducing sugar extracted from dates (70.93 g/L), S. cerevisiae produced 40 g/L of their biomass in an Erlenmeyer after only 16 h of fermentation. The kinetic performance of the S. cerevisiae strain was investigated with three unstructured models i.e., Monod, Verhulst, and Tessier. The conformity of the experimental data fitted showed a good consistency with Monod and Tessier models with R2 = 0.945 and 0.979, respectively. An excellent adequacy was noted in the case of the Verhulst model (R2 = 0.981). The values of kinetic parameters (Ks, Xm, μm, p and q) calculated by the Excel software, confirmed that Monod and Verhulst were suitable models, in contrast, the Tessier model was inappropriately fitted with the experimental data due to the illogical value of Ks (−9.434). The profiles prediction of the biomass production with the Verhulst model, and that of the substrate consumption using Leudeking Piret model over time, demonstrated a good agreement between the simulation models and the experimental data.

Previous studies have shown that fosetyl-Al (and its active component H3P03) has little in vitro effect on mycelium growth of most Oomycete, while controlling a number of diseases they cause in plants. We have shown previously that preinoculation of Citrus leaves floated on fosetyl-Al or H3P03 with the H3P03-sensitive strain of P. citrophthora (P35), not only inhibited infection by the sensitive strain, but also prevented subsequent infection by the H3P03-insensitive mutant (PAD) of the fungus.