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Laboratory support for low-resource regions is a rising global issue. As microbiological contamination is closely associated with other issues like food safety, water supply sustainability, and pub...

Managing food contamination from bacteria has been an ongoing issue in the public health and industrial fields. Enzymatic substrates possessing optical properties, e.g. fluorescence or color manifestation, are widely exploited in pathogenic/non-pathogenic bacteria culture methods. Recently, various chromogenic substrates have been utilized in the development of point-of-care diagnostic tools. Herein, four types of chromogenic substrates were exploited to develop paper-based sensors for major foodborne pathogens. We designed a compact sized three-dimensional paper device with a simple user interface. By inserting functional layers in the middle of multilayers, pre-lysis and pH regulation steps were excluded and the analysis time was subsequently reduced, while only one sample droplet was needed for the whole analysis process. After the enzymatic reactions had proceeded, target-specific colors appeared. When it was combined with enrichment, 101 cfu mL-1 of pathogens were successfully detected in 4-8 hours, while those in milk samples were readily sensed in 12 hours. The proposed bacteria sensor exhibited great advantages of low cost, portability and simple operation, while showing a respectable limit-of-detection as low as 101 cfu mL-1 and below. Significantly, we emphasize that it takes fewer steps than existing methods and provides a reduced analysis time owing to the layer functionalization.

Contamination by pesticides is an ever-increasing problem associated with fields of environmental management and healthcare. Accordingly, appropriate treatments are in demand. Pesticide detection methods have been researched extensively, aimed at making the detection convenient, fast, cost-effective, and easy to use. Among the various detecting strategies, paper-based assay is potent for real-time pesticide sensing due to its unique advantages including disposability, light weight, and low cost. In this study, a paper-based sensor for chlorpyrifos, an organophosphate pesticide, has been developed by layering three sheets of patterned plates. In colorimetric quantification of pesticides, the blue color produced by the interaction between acetylcholinesterase and indoxyl acetate is inhibited by the pesticide molecules present in the sample solutions. With the optimized paper-based sensor, the pesticide is sensitively detected (limit of detection=8.60 ppm) within 5 min. Furthermore, the shelf life of the device is enhanced to 14 days after from the fabrication, by treating trehalose solution onto the deposited reagents. We expect the paper-based device to be utilized as a first-screening analytic device for water quality monitoring and food analysis.

This study investigated whether three components of ethical management—awareness, operation, and practice—have a positive effect on corporate trust and relationship commitment in business-to-business (B2B) transactions. The study examined whether the trust formed in transactions, or relationship commitment, affects the establishment of long-term oriented relationships between companies. Further, it also aimed to determine the extent to which the authenticity of ethical management serves as a moderator that allows ethical management to influence outcome variables. The study’s sample comprised personnel (top management, management, and staff) from small- and medium-sized companies that transact with companies that mainly conduct B2B transactions. An empirical analysis was performed using data from 1323 returned questionnaires. Structural equation modeling was performed to test the hypotheses. The results showed that authenticity and the corporate ethical management components did not have moderating effects when they affected trust, however, in relationship commitment or a long-term oriented relationship, authenticity has a moderating effect when trust and commitment affect the long-term oriented relationship. This study’s empirical results contribute valuable data to the literature, as it is based on a survey conducted on actual personnel members of companies in B2B relationships.

The cyclic β-glucans and succinoglycans produced by rhizobia are required for nodulation during symbiosis with legume hosts. However, only gene deletion analyses have been used to investigate their biological importance. For future studies on the physiological activity of those during symbiosis, biochemical methods need to be developed with separate carbohydrate compounds. Here, we isolated and purified rhizobial cellular carbohydrates using various chromatographic methods. Purified cyclic β-glucans, cyclosophoraoses, were monofunctionalized with biotin using the following three steps: tosylation, azidation, and amination. The mono-6-amino-cyclosophoraoses were linked with biotinamidohexanoic acid N-hydroxysuccinimide ester. Succinoglycans and monomers were tagged with biotinamidocaproyl hydrazide at the reducing sugar via reductive amination. The resulting biotinylated rhizobial carbohydrates were characterized by Fourier transform infrared and nuclear magnetic resonance spectroscopy, matrix-assisted laser desorption/ionization time-of-flight mass spectroscopy, and electrospray ionization mass spectrometry. The resulting neoglycoconjugates can be used as solid probes to study putative plant receptors and for non-invasive imaging for in vivo tracing.

β-Cyclodextrin (β-CD) was converted into β-CD-undecenyl ether by chemical modification and subsequently covalently attached to a glass surface. The functionalized glass surface was characterized by static water contact angle and x-ray photoelectron spectroscopy. Both techniques confirmed that an excellent monolayer of β-CD was formed on the glass surface. The β-CD solid surface was used to reduce cholesterol levels in milk. In 4h, 73.6% of the cholesterol was extracted at 25°C with shaking at 170rpm. This is the highest value ever reported for milk using β-CD immobilized on a solid surface. The same surface was repeatedly used for 10 cycles and maintained its efficiency with 72±2% cholesterol reduction observed in all the cycles. X-ray photoelectron spectroscopy analysis completed after 5 and 10 cycles of cholesterol reduction showed that the β-CD on the glass surface was not degraded. The high efficiency and long-term stability of the functional monolayer was attributed to the specific structure of β-CD, which is composed of a relatively low number of functional groups and long spacer chain lengths that provide great flexibility.

Protein cages are spherical hollow macromolecules that are attractive platforms for the construction of nanoscale cargo delivery vehicles. Human heavy-chain ferritin (HHFn) is modified genetically to control the number and position of functional groups per cage. 24 β-CDs are conjugated precisely to the modified HHFn in specific locations through thiol-maleimide Michael-type addition followed by copper(I)-catalyzed azide/alkyne cycloaddition (CuAAC). The resulting human ferritins displaying β-CDs (β-CD-C90 HHFn) can form inclusion complexes with FITC-AD, which can slowly release the guest molecule reversibly in a buffer solution via non-covalent β-CD/AD interactions. β-CD-C90 HHFn can potentially be used as delivery vehicles for insoluble drugs.

Cyclosophoraoses (Cys) are synthesized by all members of the family Rhizobiaceae. Cys are a class of unbranched cyclic oligosaccharides composed glucose residues linked solely by β-1,2-glycosidic bonds, and the predominant ring size distribution is between 17 and 25 glucose residues. The biological activity of Cys has been studied in the peas, clovers, and beans (Phaseolus vulgaris L.) root-nodule bacteria Rhizobium leguminosarum bv. phaseoli. These molecules have been shown to provide two independent functions; namely, they are involved in the formation of nitrogen-fixing root nodules and promote the osmoadaptation of bacterial cells. Recent reports have shown that Cys forms inclusion complexes with a variety of hydrophobic guest molecules such as amphotericin B, fluorescein, flurbipropen, indomethacin, paclitaxel and vitamins. Much attention has thus been focused on their potential ability to form inclusion complexes with other lipophilic molecules as well as on their biological functions. To further applications of Cys, the cyclic oligosaccharides were modified with various functional groups such as carboxymethyl, sulfonyl, and succinyl groups. However, no attempts have yet been made a polymerization or oligomerization of Cys to improve the inclusion complexation ability. Similarly, cyclodextrins (cyclic β-1,4-glycans)based polymers are of interest due to their merits compared to parent CDs, such as high solubility in water and capability to solubilize a number of drugs, those with large molecular structures in particular. CD polymers can also increase the drug bioavailability. Therefore, the synthesized Cys polymers or oligomers would be used as efficient hosts for the solubility enhancement of hardly soluble drugs as well as for the bioavailability increase of natural compounds. Ibuprofen and naproxen are non-steroidal anti-inflammatory (NSAID), analgesic and antipyretic agent having main mechanism of action through block a group of enzymes called COX (cyclo-oxygenase) enzymes. They reduce pain as analgesic drugs, high temperatures as antipyrexial drugs, and swelling as anti-inflammatory drugs and make the blood less likely to clot as antithrombolic drugs. However, they have a very low solubility in water and when administered orally, it causes gastrointestinal side-effects, drowsiness and dizziness. Therefore, improvement of their solubility is challenging and rational. In the study, Cys were isolated from Rhizobium phaseoli, which is a member of the family Rhizobiaceae by ethanol precipitation and purified by various chromatographic techniques. An oligomeric cyclosophoraoses (oligo-Cys) were synthesized from cyclosophoraose (Cys), epichlorohydrin (EP) and choline chloride (CC) through a one-step polymerization procedure. The physicochemical properties of the modified oligo-Cys were characterized using various techniques including MALDI-TOF MS and H NMR spectroscopic analysis and the effects of the degree of Cys oligomerization on their drug inclusion performance was investigated by ultraviolet (UV)-visible spectroscopy. The formation of their inclusion complexes also was confirmed by fourier transform infrared spectroscopy (FT-IR). Preparation of water soluble oligo-Cys was achieved by the reaction of Cys, isolated and purified from Rhizobium phaseoli, with EP and CC in an alkaline medium by a one step procedure (Scheme 1). The reaction mixture was separated by Bio-Gel P-6 depends on degree of oligomerization. Fractionation of the reaction mixture on a gel filtration column of Bio-Gel P-6 yielded three major carbohydrate peaks (Fig. 1). In the MALDI-TOF MS spectra, the ring sizes of the Cys, which ranged from 17 to 24, were confirmed by MALDI-TOF MS spectrometry (Fig. 2(a)). Based on the MALDI-TOF mass spectrometric analysis, the average molecular weight (Mn) of Cys was determined as 3078 Da.

Cyclosophoraoses [cyclic β-(1,2)-glucan, Cys] isolated from Rhizobium leguminosarum biovar trifolii TA-1 have unique structures and high solubility, which make it a potent solubilizer for host–guest inclusion complexation. Succinylated cyclosophorasoses (S-Cys) were also synthesized by chemically modifying isolated cyclosophoraoses. In ultraviolet-visible studies using naproxen (NAP), Cys was shown to form the most stable complexes with NAP (K 1:1 = 2457.9 M−1), which was followed by the negatively charged S-Cys (K 1:1 = 357.1 M−1) at pH 3.4. A further strong reduction in the complex stability constant was observed at pH 7.5. When the reduction in the stability constant was compared with other cyclic oligosaccharides (Cys; 119.2 M−1, CD; 14.48 M−1 and HP-CD; 6.75 M−1), S-Cys (K 1:1 = 5.6 M−1) was shown to have the highest decrease in stability constant. These results suggest that the S-Cys could regulate the efficiency of inclusion complexation at external pH values. NMR studies of complex formation between NAP and Cys also showed a different correlation pattern at pH 3.4 and 7.5. This difference in correlation demonstrates that the inclusion complexes between Cys and NAP formed as a result of the differential charge distribution of the carboxyl groups of NAP. The pH-dependent inclusion behavior of Cys for NAP was also evaluated using molecular docking simulations.

Low-molecular-weight (LMW) succinoglycans (monomers, dimers, and trimers) were isolated from Sinorhizobium meliloti 1021 and have been firstly investigated by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) using 2,4,6-trihydroxyacetophenone (THAP) as an optimal matrix in the negative ion mode. The main fractions of LMW succinoglycans contain molecules assembled of octasaccharide subunits. MALDI-TOF mass spectra of the LMW succinoglycan monomers, the dimers, and the trimers showed the daughter ions resulting from the losses of the terminal galactose residues at the reducing ends, clearly indicating that the galactosyl linkages are more labile than the other glucosyl linkages. Furthermore, the losses of the acetyl groups as substituents rather than the succinyl and pyruvyl ester linkages by prompt fragmentation primarily occurred during MALDI-TOF analysis, suggesting the greater instability of acetyl linkages compared to pyruvyl and succinyl linkages.

E-mail: shjung@konkuk.ac.krReceived June 16, 2011, Accepted June 20, 2011Key Words : 4'-Hydroxyflavanone, Succinylated cyclosophoraoses, pH-Dependent, Inclusion complex, Fla-vonoidCyclosophoraoses (Cys) are unique molecules that areproduced by all members of the family Rhizobiaceae. Theywere originally found not only in the periplasmic space butalso in the extracellular media of Agrobacterium andSinorhizobium species as fast-growing soil bacteria.

it is a remarkable model for the study of bacterial photosynthesis. R. sphaeroides is a facultative photosynthetic member of the alpha-proteobacteria. The strain can heterotrophically grow not only on aerobic respiration but also on anaerobic condition, as it has diverse metabolic pathways. 2 Although α-C18 of R. sphaeroides is believed to play a role in osmotic adaptation, 1 the exact biological function and roles of α-C18 remains obscure. Catechin discussed in this work is the major component of tea flavonoids, commonly known as a class of flavan-3-ols. The flavan-3-ols are widespread compounds in the plant kingdom and are found in various natural sources including tea leaves, grape seeds, and the wood and bark of trees such as acacia and mahogany. The flavan-3-ols are reported to possess anti-oxidation, antibiotic, anti-virus, and anti-tumor pharmacological activities and also improve the immune system, reduce blood lipids and steroids, etc. 3-8 It was reported that (+)-(2R;3S)-catechin and (−)-(2S;3R)-catechin as chiral drugs showed opposite effects on glycogen metabolism and in membrane fluidity which are responsible for their pharmacological and toxicological mechanisms. 9 It was also reported that (−)-(2S;3R)-catechin has allelopathic activity, but no antibacterial activity. However, (+)-(2R;3S)catechin showed antibacterial activity but no allelopathic activity. 10 Therefore, it is important to consider powerful analytical techniques not only for the evaluation of the total amount of catechin, but also for quantitation of each enantiomer by a rapid and reproducible procedure without tedious and time-consuming pretreatments. The chiral separation of catechin has been performed by high-performance liquid chromatography (HPLC) 11-13 and more recently by capillary electrophoresis (CE) 14-17 with native or modified cyclodextrins as a chiral selector. Recently, a microbial cyclic or noncylic oligosaccharide, produced by sinorhizobial bacteria, was successfully used as a chiral additive for chiral separation of (±)-catechin in CE. 18-21 In the present study, we purified α-C18 from R. sphaeroides

α-Cyclosophoro-octadecaoses (α-C18), produced by Rhodobacter sphaeroides, are mostly homogeneous in size with 18 glucose units per ring as the predominant form. α-C18s are linked by β-(1→4)-linkages and one α-(1→6)-linkage and are also known to be highly substituted by acetyl (0-2 per mol) and/or succinoyl groups (1-7 per mol). We isolated and purified α-C18 and successfully used it in capillary electrophoresis (CE) as a chiral additive for the separation of five flavanones and flavanone-7-O-glycosides, including naringenin, hesperetin, eriodictyol, homoeriodictyol, isosakuranetin, and hesperidin. Throughout the CE experiment with unsubstituted α-C18 (uα-C18) obtained after alkaline treatment of the isolated α-C18, we found that successful chiral separation critically depends on the presence of succinate substituents attached to α-C18 in CE, suggesting that succinoylation of α-C18 is decisive for effective stereoisomeric separation.

A carboxymethylated cyclosophoraose (CM-Cys) was synthesized by the chemical modification of neutral Cys, which was isolated from Rhizobium trifolii TA-1. CM-Cys was successfully applied as a novel chiral selector for the separation of some flavonoids including catechin, 3,5,7,3',4'-pentahydroxyflavanone, hesperidin, hesperetin, isosakuranetin, naringenin, naringin, and eriodictyol. The effects of pH, chiral additive concentration, and temperature on resolution and migration time were also studied.

Summary of sensitivities taken from the square wave voltammograms of car bohydrate-doped mu lti-wall carbon nanotube-modified glass ycarbon electrodesSensitivity (current density difference vs . flavonoid concentration) (µA·µM ‒1 ·cm 2 )Rutin Rutin Q Quercetin Quercetin R Multi-wall carbon nanotube-modified glassy carbon electrod e 19.629 ± 1.5 b 20.137 ± 1.7 b 12.339 ± 1.5 b 9.277 ± 1.2 b α-cyclosophorohexadecaose-doped multi-wall carbon nanotube-modified glassy carbon electrode34.719 ± 1.5 b 19.997 ± 0.9 b 18.314 ± 1.1 b Not availableSuccinoglycan monomer M3-doped multi-wall carbon nanotube-modified glassy carbon electrode2.443 ± 0.4 b Not available 7.193 ± 0.5 a 6.427 ± 0.5 aa Peak currents shown at 0.17 V vs . Ag/AgCl was used to calculate the sensitivity slope. b Peak currents shown at 0.3 V vs . Ag/AgCl was usedto calculate the sensitivity slope. Q sensitivity to rutin in the presence of 7.5 µM quercetin dispersed in an electrolyte solution. R sensitivity to quercetin in the presence of 7.5 µM rutin dispersed in an electrolyte solution.

), or dimethyl formamide (DMF). All of these are highly toxic chemicals and poisonous materials for environment. In the present method, the sinorhiziobial octasaccharides were used as capping agenta without toxic reducing agents for the generation of Ag nano-crystals, upon the addition of basic aqueous solution. This environmentally benign method is mild, renewable and inexpensive. Succinoglycan, a symbiotically important acidic polysaccharide of

Succinoglycan, a sinorhizobial exopolysaccharide produced by Sinorhizobium meliloti, is composed of an octasaccharide subunit. S. meliloti produces both high-molecular-weight and low-molecular-weight (M(r)

Succinoglycan, a shinorhizobial exopolysaccharide produced by Shinorhizobium meliloti, is composed of an octasaccharide subunit. S. meliloti produces both high-molecular-weight and low-molecular-weight (M r < 10 000) succinoglycans that consisted of monomer, dimer, or trimer of an octasaccharide unit. We isolated and purified the monomer among low-molecular-weight succinoglycans and used this microbial linear octasaccharide as a novel chiral additive for enantiomeric separation of some flavanones such as homoeriodictyol, hesperetin, naringenin, and isosakuranetin in CE. Throughout the present investigation, we firstly used noncyclic oligosaccharides for the chiral separation of flavanones. We also found that successful enantioseparation of four flavanones depends on the presence of succinate substituents of the linear monomeric octasaccharide in CE, suggesting that succinylation of succinoglycan monomer is decisive for the effective enantiomeric separation.

The glassy carbon electrode (GCE) was modified with multi-wall carbon nanotubes (MWNTs) and succinoglycan monomers (M1, M2 and M3) by dropping small volume of a solution mixture on the GCE surface and the modified electrode was electrochemically characterized for monitoring quercetin that is dispersed in an aqueous electrolyte solution. Quercetin, as an antioxidant, has attracted researcher’s much attention to the determination of its concentration in a variety of environment, because it has many biological activities such as cardiovascular protection, anticancer activity, and antiallergy activity. Bare GCE and MWNTs-modified GCE do not show any redox peak of quercetin in a potential range of 0–0.5 V vs . SCE. Three different succinoglycan monomers M1, M2, and M3 were separately immobilized on the GCE surface together with the MWNTs to prepare three different kinds of sensing electrodes, for example, (MWNTs + M1)/GCE, (MWNTs + M2)/GCE, and (MWNTs + M3)/GCE. The GCE modified with MWNTs and β-cyclodextrin (β-CD) complex (MWNTs + β-CD/GCE) was also prepared for comparing its electrochemical behavior with those of the (MWNTs + M1)/GCE, the (MWNTs + M2)/GCE, and the (MWNTs + M3)/GCE. Results showed that the reduction and the oxidation peaks around 350 and 400 mV vs . SCE were observed with the (MWNTs + β-CD)/GCE, the (MWNTs + M2)/GCE, and the (MWNTs + M3)/GCE. Likely to the (MWNTs + β-CD)/GCE, cyclic voltammograms of the (MWNTs + M3)/GCE showed pH-dependent characteristics. Anodic peaks shown around 400 mV vs . SCE in the cyclic voltammograms of the (MWNTs + M2)/GCE and the (MWNTs + M3)/GCE are due to the oxidation of quercetin that is captured by the immobilized M2 or M3. But, because M1 does not have a succinyl group as a substituent, the (MWNTs + M1)/GCE does not show any redox peak of the cyclic voltammogram in the given potential range. Succinyl groups in succinoglycan monomers are to be associated with the conjugation of MWNTs and water-dispersed quercetin molecules. Square wave voltammograms and calibration curve of the (MWNTs + M3)/GCE were shown in the range of 2.36–59 μM of quercetin and about sixteen times of higher sensitivity was observed compared with the measured sensitivity of the (MWNTs + β-CD)/GCE. Electrode kinetic parameters, V max and K m of M3 in an aqueous medium obtained from the Lineweaver–Burk plots were 15 μA and 7.82 μM, respectively.

Cyclic β-(1→3),(1→6)-glucans, microbial cyclooligosaccharides produced by Bradyrhizobium japonicum USDA 110, were used as novel chiral additives for the enantiomeric separation of some flavanones such as eriodictyol, homoeriodictyol, hesperetin, naringenin, and isosakuranetin in capillary electrophoresis (CE). Among the flavanones, eriodictyol was separated with the highest resolution ( R s 5.66) and selectivity factor ( α 1.18) when 20 mM cyclic β-(1→3),(1→6)-glucans were added to the background electrolyte (BGE) at pH 8.3.

Throughout this interact property, cyclic β-(1→3),(1→6)-glucans are suspected of being involved in complexationwith various plant flavonoids.Catechin is a polyphenolic compound which has beenisolated from a variety of natural sources including tealeaves, grape seeds, and the wood and bark of trees such asacacia and mahogany. The catechin shows strong antioxi-dant activity both

Zooglan, the acidic exopolysaccharide produced by Zoogloea ramigera functioned as a novel catalytic carbohydrate for methanolysis of 4-benzylidene-2-phenyloxazolone, one of 5(4H)-oxazolones. The conversion rate was enhanced by zooglan with increasing reaction temperature up to 70 °C. Zooglan accelerated the conversion about 189-fold for the oxazolone compound comparing with a control at 70 °C, when the conversion rate (% conversion/min) was determined at the mid point of the inflection on the curves fitted to the data points measured. Herein, we propose that complex carbohydrates derived from microorganisms, containing zooglan could have potentials as catalysts in specific organic reactions.

The pH-dependent inclusion complexation of carboxymethylated cyclosophoraoses (CM-Cys) with N -acetylphenylalanine was investigated. The CM-Cys were synthesized through chemical modification of cyclosophoraoses, cyclic-(1→2)-β- d -glucans produced by Rhizobium meliloti 2011. The study was conducted by ultraviolet-visible (UV–vis) and nuclear magnetic resonance (NMR) spectroscopic analyses. A continuous variation plot based on the UV–vis spectroscopic analysis reveals that the inclusion complexes have a predominantly 1:1 stoichiometry. The NMR studies, which include a two-dimensional rotating frame nuclear Overhauser effect spectroscopy (ROESY) technique, show that the complexes of CM-Cys with N -acetylphenylalanine exist with different inclusion structures at pH 3 and 7. Furthermore, the NMR titration study shows that the inclusion complexes kept the pH-dependent binding constants ( K b ), based on the Benesi–Hildebrand procedure, K b to be 189±6 M −1 for pH 7 and 100±12 M −1 for pH 3. Given that the pH-dependent changes of binding positions in the CM-Cys is due to the differential charge distribution of the carboxyl groups within the CM-Cys, these results suggest that the CM-Cys could regulate the efficiency of the inclusion complexation corresponding to the external pH change. Simulated annealing molecular dynamics simulations (SA-MD) were also performed to discuss the pH-dependent conformational change of CM-Cys.

Neutral cyclosophoraoses (unbranched cyclic β-1,2-d-glucans) produced by the Rhizo-bium meliloti 2011 were prepared by size exclusion and anion-exchange chromatographic techniques. The degree of polymerization (DP) of isolated cyclosophoraoses was determined by matrix associated laser desorption/ionization mass spectrometry (MALDI/MS) techniques. A family of purified neutral cyclosophoraoses (DP 17–27) was used as a host for the inclusion complexation with hardly soluble ergosterol. High performance liquid chromatographic (HPLC) analysis showed that it induced much enhanced solubility of ergosterol compared to β-cyclodextrin. In order to understand the molecular basis of the complex forming ability of cyclosophoraoses, a Monte Carlo (MC) docking-minimization method was used for host-guest complex formation of cyclosophoraoses or β-cyclodextrin with ergosterol. From the MC simulation we propose the `hand-shake' mechanism for complexation of cyclosophoraoses with ergosterol.

Succinoglycan monomers (M1, M2, and M3) are octasaccharides with acetyl, pyruvyl, and/or succinyl groups as substituents derived from Sinorhizobium meliloti 1021. The dissociation patterns of the octasaccharides caused by low-energy collision-activated dissociation (CAD) were investigated using triple quadrupole tandem mass spectrometry (MS) equipped with an electrospray ionization (ESI) source with increasing collision energy (CE) in negative ion mode. None of the succinoglycan monomers were fragmented at a CE of -25eV. When the CE was applied to -50 or -70eV, the loss of the terminal Gal residue and/or the succinyl group of the monomers was observed in the product ion scan mode. Interestingly, the acetyl and the pyruvyl groups in the succinoglycan monomers were not lost even when a CE of -70eV was applied, indicating that the substituents are more stable than the succinyl group in the octasaccharides.

Shinorhizobial cyclosophoraose (cyclic β-(1→2)-glucan) or succinoglycan monomer (SGM 2), which has one acetyl, pyruvyl, and succinyl group, functions as a morphology-directing agent for the synthesis of pure trigonal selenium nanowires by using ascorbic acid (vitamin C) as the reducing agent. The synthesis was achieved in water at room temperature. Under these experimental conditions, the diameters of the as-prepared Se nanowires were varied in the range of 34–120 nm by cyclosophoraose and of 33–66 nm by SGM 2, in which the nanowires were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Raman spectroscopy. Through this study, we propose that Shinorhizobial cyclic and linear oligosaccharides have morphologically directing functions for the synthesis of single-crystalline selenium nanowires by green chemical methods.

Some microbial carbohydrates have been used as catalysts for the multicomponent Strecker reaction using trimethylsilyl cyanide (TMSCN). Alpha-Cyclosophorohexadecaose (alpha-C16) derived from Xanthomonas species and succinoglycan monomers derived from Rhizobium species acted as catalytic carbohydrates in the mixture solutions of methanol and water. Malonaldehyde bis(phenylimine) as a substrate was completely converted (yield: 100%) into its product to 100% by both alpha-C16 and the succinoglycan monomer (M2), having acetyl, pyruvyl, and succinyl groups as substituents after 1h. The catalytic abilities of the carbohydrates were dependent on the inherent structures of the substrates used in this study, where substrate 1 having a symmetrical structure rather than the others was favorably reacted with the alpha-C16 and M2. Through this study, we suggest that the microbial carbohydrates used in this study could be expected to be environmentally-benign catalysts for the synthesis of alpha-aminonitriles.

Protonic currents play a vital role in electrical signalling in living systems. It has been suggested that succinoglycan plays a specific role in alfalfa root nodule development, presumably acting as the signaling molecules. In this regard, charge transport and proton dynamics in the biopolymer exopolysaccharide succinoglycan have been studied by means of electrical measurements and nuclear magnetic resonance (NMR) spectroscopy. In particular, a dielectric dispersion in the system has revealed that the electrical conduction is protonic rather electronic. Besides, our laboratory- and rotating-frame 1H NMR measurements have elucidated the nature of the protonic conduction, activation of the protonic motion being associated with a glass transition.