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Tomato (Solanum lycopersicum) are consid­ered one of the most important vegetable crops and infected by numbers of different diseases. Studying the use of biological alternatives, instead of chemical substances against plant diseases became necessary for the treatment by beneficial microorganisms endophytes, which can excrete natural products benefits to plant in reducing disease severity, promoting growth and inducing plant defence mechanisms. In this work, three endophytes strains were isolated from tomato stems and their 16srDNA have been found to belong to Bacillus species. The first strain was named BMG100, the second BMG101 and the third BMG102. Two Bacillus strains BMG100 and BMG101 have been found to harbour synthetases genes from three lipopeptides families; surfactin, plipastatin, and iturin (mycosubtilin) which can be detected by degenerated primers designed to detect the presence of synthetases genes encoding lipopeptides. The lipopeptides production was proved by their quantification using High Performance Liquid Chromatography (HPLC), whereas BMG100 produced 105, 178 and 293 mg/L of plipastatin, mycosubtilin and surfactin, respectively, BMG101 produced 385 mg/L of surfactin and 236 mg/L of mycosubtilin, while BMG102 showed no lipopeptides production. Keywords: Tomato; Endophytic bacteria; Lipopeptides; Bacillus species

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Fruit peels annually accumulate in huge amounts, fruit wastes are rich in lignocellulosic component which can be recovered into mono simple carbohydrates able to utilize for bioethanol production. The enzymatic hydrolysis of lignocelluloses is known to be a key to the second-generation biofuel, the challenge is the still expensive enzymes involved in the saccharification process, loss of the most hemicellulose pentose sugars which were non-fermentable as base, beside the presence of hampers lignin thus require to resolve its problem. As part of study, followed the cost-effective means for bioethanol producing from four fruit peels (Banana, Orange, Mango and Watermelon), yielding of enzymes from co-fungal cultivation carried by Aspergillus niger and Phanerochaete chrysosporium, followed by co-fermentation of the saccharified sugars using yeast belong to Saccharomyces cerevisiae and Kluyveromyces marxianus which contributed for bioethanol production in 8 L lab-scale reactor. The fermented sugars recovering was reached to 27.77 g.l -1 from banana peels which were found to be good exploited as potential raw source, co-fungal enzymatic hydrolysis followed by yeast co-fermentation led to substantial yield by 10.74 g.l -1 , the adding of calcium oxide increased the purity which leads finally to 97.5 wt % of pure bioethanol. Thrust towards fossil fuels replacement with renewable clean fuels such as bioethanol by using fruit peels residuals which are considered renewable energy source may also help in CO2 mitigation.

Twelve dissimilar plant associated bacterial colonies were isolated from five different tomato seedlings, the Non Ribosomal Lipopeptides genes were detected by degenerated primers technique in the twelve tomato endophytic isolates, only the long rode bacilli endophytic strains were found to harbour the lipopeptides synthetases genes, these three strains were given laboratory names of (BMG100, BMG101 and BMG102) for further pursuit. Partial sequencing of 16s RNA gene and protein profile analysis for the three bacilli isolates showed that all isolates belonged to Bacillus subtilis. The lipopeptides production by HPLC analysis revealed that all the endophytic isolates from tomato stems had the ability to produce lipopeptides except the third isolate named B. subtilis BMG102 showed no production. different levels of volumetric oxygen transfer coefficient (KL a) were used as cursors for lipopeptides production. The maximum concentration of surfactin type was about 1431, 529 and 437 mg.L -1 , the plipastitin (fengycin type ) was 360 198 mg.L -1 and zero while the Mycosubtilin (iturin type) was zero, 228 and 414 mg.L -1 for the strains B. subtilis ATCC21332, BMG100 and BMG101, respectively. Surfactin production is visibly optimal at high oxygen transfer (k L a) and showed more than 0.07 S -1 , while the optimum production of the fengycin and iturin could be observed at mild values of O 2 transfer (k L a) which equal 0.01 and 0.015 S -1 respectively. The antibacterial -antifungal effects of the three B.subtilis extracts collected during lipopeptides productivity regimes showed inhibition activity againstPseudomonas syringae, Ralstonia solanacearum and Erwinia amylovora, as will as the antifungal activity against Aspergillus niger, Phanerochaete chrysosporium and Alternaria alternata. These results indicate potential use of B.subtilis strains as biocontrol agents, especially when considering commercial implementation. Studies regarding the lipopeptides applications, should also be considered as this will influence the efficacy of the lipopeptides against the target organisms.