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Drought is more concerned to be a huge problem for agriculture as it affects plant growth and yield. Endophytic bacteria act as plant growth promoting bacteria that have roles for improving plant growth under stress conditions. The properties of four strains of endophytic bacteria were determined under water deficit medium with 20% polyethylene glycol. Bacillus aquimaris strain 3.13 showed high 1-aminocyclopropane-1-carboxylate (ACC) deaminase production; Micrococcus luteus strain 4.43 produced indole acetic acid (IAA). Exopolysaccharide production was high in Bacillus methylotrophicus strain 5.18 while Bacillus sp. strain 5.2 did not show major properties for drought response. Inoculation of endophytic bacteria into plants, strain 3.13 and 4.43 increased height, shoot and root weight, root length, root diameter, root volume, root area and root surface of Jerusalem artichoke grown under water limitation, clearly shown in water supply at 1/3 of available water. These increases were caused by bacteria ACC deaminase and IAA production; moreover, strain 4.43 boosted leaf area and chlorophyll levels, leading to increased photosynthesis under drought at 60 days of planting. The harvest index was high in the treatment with strain 4.43 and 3.13 under 1/3 of available water, promoting tuber numbers and tuber weight. Inulin content was unchanged in the control between well-watered and drought conditions. In comparison, inulin levels were higher in the endophytic bacteria treatment under both conditions, although yields dipped under drought. Thus, the endophytic bacteria promoted in plant growth and yield under drought; they had outstanding function in the enhancement of inulin content under wellwatered condition.

In this work, the effects of co-inoculation between an arbuscular mycorrhizal fungus (AMF) and a phosphate solubilizing bacteria (PSB) to promote the growth and production of sunchoke under field condition were investigated during 2016 and 2017. Four treatments were set up as follows: plants without inoculation, with AMF inoculation, with PSB inoculation and with co-inoculation of PSB and AMF. The results showed the presence of PSB and AMF colonization at the harvest stage in both years. This suggested the survival of PSB and successful AMF colonization throughout the experiments. According to correlation analysis, PSB positively affected AMF spore density and colonization rate. Also, both AMF and PSB positively correlated with growth and production of sunchoke. Co-inoculation could enhance various plant parameters. However, better results in 2016 were found in co-inoculation treatment, while AMF inoculation performed the best in 2017. All of these results suggested that our AMF and PSB could effectively promote growth and production of sunchoke under field conditions. Such effects were varied due to different environmental conditions each year. Note that this is the first study showing successful co-inoculation of AMF and PSB for promoting growth and yield of sunchoke in the real cultivation fields.

Arbuscular mycorrhizal fungi (AMF) and phosphate solubilizing bacteria (PSB) could interact synergistically because PSB solubilize sparingly available phosphorous compounds into orthophosphate that AMF can absorb and transport to the host plant. Little is known about the interactions between these two groups in terms of promoting Jerusalem artichoke, Helianthus tuberosus L., which is widely planted by farmers because of its high inulin content. Production depends mainly on synthetic fertilizers as source of plant nutrients. This study aimed to isolate and characterize PSB and investigate the effects of co-inoculation of AMF and PSB on plant performance and inulin accumulation. Isolate UDJA102x89-9, identified as Klebsiella variicola (KV), showed phosphate-solubilizing ability and produced high amounts of several organic acids in vitro and of indole-3-acetic acid (IAA). The experiment combined KV and two AMF species (Glomus multisubtensum (GM) and Rhizophagus intraradices (RI)). Co-inoculation of KV with RI, in combination with rock phosphate, showed the largest increases in plant growth and tuber inulin content, compared both to an unfertilized and fertilized control. This result would reveal whether the phosphate solubilization and IAA property of the PSB in vitro played a significant role in changing plant growth and production, and the available P was subsequently taken up and transported to plant roots by AMF. The high combined effect may have the potential for use by farmers in the future as a biofertilizer for inulin production by Helianthus tuberosus L.

The endophytic bacteria isolated from the leaves, stems, tubers and roots of Helianthus tuberosus L. (Jerusalem artichoke) were studied and characterized. The isolated endophytes were clustered by amplified ribosomal DNA restriction analysis (ARDRA) technique and identified by 16 S rRNA sequencing to demonstrate bacteria diversity, mainly in Bacillus, Pseudomonas, Stenotrophomonas, Microbacterium, Curtobacterium. The proportions of endophytes exhibited colonization (from most to least) in stems, leaves, roots and tubers. The more isolates had ACC (1 aminocyclopropane-1-carboxylate) deaminase and nitrogen fixation, the less they showed phosphate and potassium solubilization. Antifungal activity was exhibited only in Bacillus, while many isolates had stress tolerance in polyethylene glycol. Six endophytic bacteria were recolonized into 2 varieties of Jerusalem artichoke (HEL65 and JA102xJA89) and showed increases in height, root and stem weight, and tuber number. The potential local endophyte, Pantoea ananatis 4.14 responded to the tuber by increasing inulin content, which is a valued product of Jerusalem artichoke.

Magnetic membranes based on bacterial cellulose (BC) nanocomposites have been extensively researched. However, most magnetic nanoparticles (NPs) incorporated in the BC matrix were focused on soft magnetic phases, which limited the extensive use of magnetic BC membranes. Therefore, this work proposes a method to fabricate hard magnetic membrane based on the BC matrix and magnetically hard phase barium ferrite (BFO) NPs. The nanocomposites showed the peaked tensile strength and modulus at the low concentration of BFO whereas the magnetization increased drastically with the BFO content. They also demonstrate the high flexibility up on bending and the sensitivity to external magnetic fields. Furthermore, unlike other magnetic BC membranes, the BC/BFO nanocomposites exhibited the hard magnetic properties, i.e. they could retain their magnetic attraction after being magnetized by a permanent magnet. These properties open the possibility to employ these materials in various fields, such as information storage, anti-couterfeit or electromagnetic shieldings.

Recently, renewable energy is very important use for industrial development, transport because it is environmental friendly and can reduce high cost of imported fossil fuel. The evolution of biodiesel production has been reported in many researchers. Transesterification process which is mainly reaction for biodiesel is required catalysts such as acid, base catalyst or biocatalyst. In this study, 134 isolates were selected from soil contaminated with oil in Khon Kaen region by using culture medium containing 1% olive oil and 0.0001% rhodamine B with incubation at 30° C for 48 h. These lipase-producing bacteria were also determined their activities on agar medium with 1% tributyrin. The isolate NA37 showed high lipase activity (190 mU/ml) detecting with p-nitrophenyl palmitate as a substrate. Cooking-palm oil was contributed lipase production of the NA37 more than other oils. The optimum temperature and pH for lipase production is 30° C and pH 9, resulting in lipase activity of 481 mU/ml. 

The consumption of salted mackerel shiokara contaminated with halophilic bacteria that have histidine decarboxylase enzymes can lead to histamine poisining in humans. In previous research, Tetragenococcus halophilus strains were found to be the dominant salt-tolerant bacteria in mackerel shiokara samples, and two such strains were isolated and identified as T. halophilus A116 and A124 using 16S rDNA and the API 50 CHL test. In the work described here, in order to understand the regulation of histamine production, the hdcA gene was investigated. Only the A124 strain was found to contain the hdcA gene. The hdcA gene cluster consisted of the partial genes dapE, tnpA, and hdcRS, as well as the full-length genes hdcP, hdcA, and hdcB. This gene cluster was located in the chromosomal DNA of the A124 strain. Transcription of the hdcA gene was determined under various pH conditions using qRT-PCR. pH (3.0–7.0) did not have an effect on hdcA expression in T. halophilus A124. In contrast, the growth of strain A124 was very limited at pH

Laccase, a blue copper oxidase, is an enzyme that is involved in the oxidation of aromatic compounds which prove otherwise difficult to degrade in the environment. The substrates of laccase are xenobiotics and synthetic dyes. The isolation of bacterial strains was investigated for laccase production and its activity. The medium for production was a high nitrogen medium containing aromatic compounds as inducers, for instance, guaiacol, phenol red and black liquor (from pulp and paper industry) gave higher production. The enzymes of isolated bacteria had the optimum pH and temperature in the range of 3 to 5 and 32 to 37°C, respectively. Furthermore, metal ions had an effect on the laccase enzyme; MnSO4 and CuSO4 showed a significant increase in laccase activity. However, the effects of metal ions on either laccase production or laccase activity were not clear. The laccase production and activity were dependent on species of bacterial strains. The laccase bacteria were identified as Rhodococcus sp., Enterobacter sp., Staphylococcus saprophyticus and Delftia tsuruhatensis. The synthetic dyes were determined in the reduction of color using the G32 strain; this strain gave 20 to 65% of dye reduction within three days.Key words: Bacterial laccases, 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS), inducers, metal ions, dye reduction.

Genus Bacillus is a spore-forming bacterium that has unique properties in cell differentiation, allowing the forming of spores in stress conditions and activated in the vegetative cell, with suitable environments occurring during the life cycle acting as a trigger. Their habitat is mainly in soil; thus, many species of Bacillus are associated with plants as well as rhizosphere bacteria and endophytic bacteria. Signal transduction is the principal mechanism of interactions, both within the cell community and with the external environment, which provides the subsequent functions or properties for the cell. The antimicrobial compounds of Bacillus sp. are potentially useful products, which have been used in agriculture for the inhibition of phytopathogens, for the stimulation of plant growth, and in the food industry as probiotics. There are two systems for the synthesis of these substances: nonribosomal synthesis of cyclic lipopeptides (NRPS) and polyketides (PKS). For each group, the structures, properties, and genes of the main products are described. The different compounds described and the way in which they co-exist exhibit the relationship of Bacillus substances to plants, humans, and animals.