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This study investigated the effect of Pseudomonas stutzeri inoculation on Lemna minor treated with Cu(OH) 2 nanopesticide (NP). The results showed that P. stutzeri inoculation increased the relative growth rate (RGR) in NP-treated plants. Although chlorophyll and carotenoid contents decreased significantly in NP-treated plants, P. stutzeri inoculation led to an increase in chlorophyll and carotenoid contents in NP-treated plants. Copper (Cu) content increased with increasing NP concentration, but it decreased significantly in the presence of P. stutzeri. NP treatment caused increased H 2 O 2 and TBARS levels, as well as proline levels. However, P. stutzeri inoculation led to decreased H 2 O 2 and TBARS levels and increased SOD, POX, GST, GR, GPX, and DHAR activities. The expression of genes encoding SOD, GST, metacaspase-1, and chlorophyllase was upregulated by NP treatment alone. Additionally, when plants were inoculated with P. stutzeri , the expression of these genes was further enhanced. In conclusion, P. stutzeri inoculation had a positive effect on the growth and antioxidant system of L. minor treated with NP as it enhanced RGR, increased chlorophyll and carotenoid contents, and decreased Cu content and oxidative stress. These findings suggested that P. stutzeri has the potential to promote aquatic plant growth and counteract the negative impacts of NP on these plants. • Cu(OH) 2 NP treatment negatively affected photosynthetic pigments, caused lipid peroxidation, and decreased growth in L. minor. • Under Cu(OH) 2 NP stress, Pseudomonas stutzeri inoculation reduced Cu content, H 2 O 2 and TBARS levels, enhanced antioxidant enzyme activities in L. minor. • Inoculation of P. stutzeri under Cu(OH) 2 NP stress alleviated oxidative stress by up-regulating the expression of genes related to antioxidant system. • Under Cu(OH) 2 NP stress, P. stutzeri inoculation reduced NP-induced cytotoxicity by down-regulating the expression of metacaspase-1 and chlorophyllase genes. [ABSTRACT FROM AUTHOR]

Abstract: The present study was conducted to identify and characterize the thermophilic bacteria isolated from various hot springs in Turkey by using phenotypic and genotypic methods including fatty acid methyl ester and rep-PCR profilings, and 16S rRNA sequencing. The data of fatty acid analysis showed the presence of 17 different fatty acids in 15 bacterial strains examined in this study. Six fatty acids, 15:0 iso, 15:0 anteiso, 16:0, 16:0 iso, 17:0 iso, and 17:0 anteiso, were present in all strains. The bacterial strains were classified into three phenotypic groups based on fatty acid profiles which were confirmed by genotypic methods such as 16S rRNA sequence analysis and rep-PCR genomic fingerprint profiles. After evaluating several primer sets targeting the repetitive DNA elements of REP, ERIC, BOX and (GTG)5, the (GTG)5 and BOXA1R primers were found to be the most reliable technique for identification and taxonomic characterization of thermophilic bacteria in the genera of Geobacillus, Anoxybacillus and Bacillus spp. Therefore, rep-PCR fingerprinting using the (GTG)5 and BOXA1R primers can be considered as a promising genotypic tool for the identification and characterization of thermophilic bacteria from species to strain level. [Copyright &y& Elsevier]

Abstract: Fatty acid (FAs) and RAPD profiles were used to examine phenotypic and genetic relationships between eight Astragalus species including Astragalus maximus Willd. var. maximus, Astragalus coadunatus Hub. Mor. & Chamb., Astragalus kurdicus Boiss. var. kurdicus, Astragalus lagurus Willd, Astragalus christianus L., Astragalus cicer L., Astragalus atrocarpus Champ & Matthews and Astragalus onobrychioides Bieb., which were wildly growing in eastern Anatolia region of Turkey. All of the eight Astragalus species tested in this study were separated based on the presence and composition of 45 different FAs. Four of the Astragalus species including A. coadunatus, A. lagurus, A. christianus, and A. atrocarpus were rich in terms of FA contents containing at least 22–31 different FAs. The relative proportions of two fatty acids, 16:0, and 18:1:ω8c were higher in these four Astragalus species. The remaining species have limited number of FAs with unique FAMEs profiles. Six of the 10 decamer primers examined were selected to find out genetic polymorphism in Astragalus species. A total of 98 polymorphic bands were observed, ranging in size from 250bp to 3000bp. The RAPD results suggested that A. atrocarpus, A. onobrychioides and A. kurdicus are closely related and completely different from the other species. Six genetically distinct groups were found among the species of Astragalus. High genetic variations among Astragalus species growing wildly in eastern Anatolia region of Turkey may imply the differences in their origins. The results in the present study suggested that both RAPD and FA analyses are useful for differentiation of Astragalus species. [Copyright &y& Elsevier]

Effect of Alternaria alternata (OG14) isolated from a rock lichen (Xanthoria sp.) was investigated on the relief of boron stress in wheat. To determine the tolerance level to B stress, the fungus was grown at increasing boric acid (BA) concentrations in the range of 0.0–2.5 M. No significant change in colony development of the fungus was observed up to 1 M BA application compared to the control but after this dose, it decreased depending on the increase in the BA dose. When the element content of wheat seedlings was evaluated by ICP-MS, BA application increased B content together with Mg, P, K, Fe contents of the seedlings to very high levels compared to the control. However, fungus + BA treatments decreased the content of B and the other elements in the seedlings. The BA applications resulted in an increase in the levels of reactive oxygen species, including H 2 O 2 and O 2 .−as well as lipid peroxidation in the seedlings. However, when the fungal inoculation was performed under the same BA conditions, the levels of these parameters decreased. The fungus inoculation stimulated the activity of all studied enzymes compared to BA applications. BA applications alone increased non - enyzmatic the oxidized ascorbate level more than the reducing ascorbate, leading to a decrease in the AsA/DHA ratio. The results show that A. alternata treatment can mitigate the negative effects of B stress on wheat seedlings by reducing ROS, LPO, B content, increasing the capacity of enzymatic and non-enzymatic antioxidants, and improving root and shoot length. [Display omitted] • The fungal treatment reduced the high B content in wheat seedlings caused by boric acid (BA) application. • The fungal treatment decreased ROS accumulation and lipid peroxidation thereby mitigating the negative effects of BA stress on wheat seedlings. • The fungal treatment enhanced enzymatic and non-enzymatic antioxidant capacity of wheat seedlings thus improving their stress tolerance. [ABSTRACT FROM AUTHOR]

Abstract: Origanum vulgare L. (oregano) is a flavoring herb widely used around the world. In the present study, crude extract of O. vulgare L. (oregano) and its petroleum ether, chloroform, ethyl acetate, n-butanol, water fractions were prepared in order to isolate and investigate antimutagenic compounds from the active extract through the bacterial genotoxicity assay guided fractionation procedures. The methanol extract and its n-butanol fraction showed significant antimutagenic activity. In the end of sub-fractionation process of the n-butanol extract, luteolin 7-O-glucuronide and luteolin 7-O-xyloside were isolated. These compounds showed significant antimutagenic activity against 9-Aminoacridine and N-Methyl-N′-nitro-N-nitrosoguanidine mutagenicity. The inhibition rates ranged from 22.1% (luteolin 7-O-xyloside: Salmonella typhimurium TA1537 – 0.4mM/plate) to 67.8% (luteolin 7-O-glucuronide: S. typhimurium TA1537 – 0.8μM/plate). In conclusion, the results revealed that luteolin 7-O-glucuronide and luteolin 7-O-xyloside are two of the antimutagenic compounds of O. vulgare L. ssp. vulgare. [Copyright &y& Elsevier]