• Food Science of Animal Resources
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• v.26 no.4
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• pp.441-446
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• 2006

The objective of this study was to investigate volatile compounds extracted from fresh pork belly during storage time at 4 or $20^{\circ}C$. Approximately thirty-one volatile compounds includingaromatics (6), aldehydes (6), acids (5), alcohols (4), ketones (4), alkanes (4), alkenes (1) and amines (1) in fresh pork belly were identified. Among them, volatile compounds such as 1-butanol, propane, 2-butanol, 3-hydroxy-2-butanone, acetic acid, 3-methyl-1-butanol, 1-pentanol, phenol, 2-pentyl-furan, indole and 2-dodecanone correlated with storage temperature and storage time. Aldehydes including hexanal and hexadecanal at 4t were the predominant volatile compounds, whereas at $20^{\circ}C$ storage, aromatics including phenol and indole, and alcohols including 2-butanol and 1-butanol were the predominant volatile compounds. Contents of 1-butanol, 2-butanol, 3-hydroxy-2-butanone, acetic acid, phenol and indole increased markedly with increased storage time, and 1-butanol, 2-butanol, 3-hydroxy-2-butanone, acetic acid, indole and 2-dodecanone were only detected at $20^{\circ}C$ storage.

• Journal of Applied Biological Chemistry
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• v.44 no.4
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• pp.173-176
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• 2001

This report concerns the role of indole-3-acetic acid (IAA) in bacterial pustule disease of soybean. Pustule production in soybean leaves caused by Xanthomonas axonopodis pv. glycines was accompanied by a drastic increase in IAA content of host tissues. The phytopathogenic bacterium synthesized IAA in a tryptophan concentration-dependent manner when grown in a defined minimal medium. In complex media, however, the pathogen showed no response to tryptophan feeding, implying that the bacterial biosynthetic machinery of IAA is strictly regulated by nutrient availability of its growth environments. The results may suggest that IAA of bacterial origin and tryptophan of plant origin be involved in the process of pustule symptom development in soybean.

• Mycobiology
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• v.47 no.3
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• pp.292-300
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• 2019

IAA biosynthetic pathways in a basidiomycetous yeast, Rhodosporidiobolus fluvialis DMKU-CP293, were investigated. The yeast strain showed tryptophan (Trp)-dependent IAA biosynthesis when grown in tryptophan supplemented mineral salt medium. Gas chromatography-mass spectrometry was used to further identify the pathway intermediates of Trpdependent IAA biosynthesis. The results indicated that the main intermediates produced by R. fluvialis DMKU-CP293 were tryptamine (TAM), indole-3-acetic acid (IAA), and tryptophol (TOL), whereas indole-3-pyruvic acid (IPA) was not found. However, supplementation of IPA to the culture medium resulted in IAA peak detection by high-performance liquid chromatography analysis of the culture supernatant. Key enzymes of three IAA biosynthetic routes, i.e., IPA, IAM and TAM were investigated to clarify the IAA biosynthetic pathways of R. fluvialis DMKU-CP293. Results indicated that the activities of tryptophan aminotransferase, tryptophan 2-monooxygenase, and tryptophan decarboxylase were observed in cell crude extract. Overall results suggested that IAA biosynthetic in this yeast strain mainly occurred via the IPA route. Nevertheless, IAM and TAM pathway might be involved in R. fluvialis DMKU-CP293.

• Proceedings of the Botanical Society of Korea Conference
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• 1995.06a
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• pp.12-26
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• 1995

• Journal of Microbiology and Biotechnology
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• v.18 no.7
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• pp.1235-1244
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• 2008

Indole-3-acetic acid (IAA) is produced commonly by plants and many bacteria, however, little is known about the genetic basis involving the key enzymes of IAA biosynthetic pathways from Bacillus spp. IAA intermediates from the Gram-positive spore-forming bacterium Paenibacillus polymyxa E681 were investigated, which showed the existence of only an indole-3-pyruvic acid (IPA) pathway for IAA biosynthesis from the bacterium. Four open reading frames (ORFs) encoding indole-3-pyruvate decarboxylase-like proteins and putative indole-3-pyruvate decarboxylase (IPDC), a key enzyme in the IPA synthetic pathway, were found on the genome sequence database of P. polymyxa and cloned in Escherichia coli DH5$\alpha$. One of the ORFs, PP2_01257, was assigned as probable indole-3-pyruvate decarboxylase. The ORF consisted of 1,743 nucleotides encoding 581 amino acids with a deduced molecular mass of 63,380 Da. Alignment studies of the deduced amino acid sequence of the ORF with known IPDC sequences revealed conservation of several amino acids in PP2_01257, essential for substrate and cofactor binding. Recombinant protein, gene product of the ORF PP2_01257 from P. polymyxa E681, was expressed in E. coli BL21 (DE3) as a glutathione S-transferase (GST)-fusion protein and purified to homogeneity using affinity chromatography. The molecular mass of the purified enzyme showed about 63 kDa, corresponding closely to the expected molecular mass of IPDC. The indole-3-pyruvate decarboxylase activity of the recombinant protein, detected by HPLC, using IPA substrate in the enzyme reaction confirmed the identity and functionality of the enzyme IPDC from the E681 strain.

• Bulletin of the Korean Chemical Society
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• v.25 no.9
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• pp.1321-1325
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• 2004

Sodium dodecyl sulfate (SDS), an anionic surfactant, can strongly adsorb at the surface of a carbon paste electrode (CPE) via the hydrophobic interaction. In pH 3.0 $Na_2HPO_4$-citric acid buffer (Mcllvaine buffer) and in the presence of SDS, the cationic indole-3-acetic acid (IAA, $pK_a$ = 4.75) was highly accumulated at the CPE surface through the electrostatic interaction between the negative-charged head group of SDS and cationic IAA, compared with that in the absence of SDS. Hence, the oxidation peak current of IAA increases greatly and the oxidation peak potential shifts towards more negative direction. The experimental parameters, such as pH, varieties of surfactants, concentration of SDS, and scan rate were optimized for IAA determination. The oxidation peak current is proportional to the concentration of IAA over the range from $5\;{\times}\;10^{-8}$ mol/L to $2\;{\times}\;10^{-6}$ mol/L. The detection limit is $2\;{\times}\;10^{-8}$ mol/L after 3 min of accumulation. This new voltammetric method was successfully used to detect IAA in some plant leaves.

• Journal of Environmental Science International
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• v.13 no.6
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• pp.513-518
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• 2004

3-weeks old Commelina was transferred to and grown in Hoagland solution (Control, $100\muM$ $Cd^{2+}$, $100\muM$ $Cd^{2+}$+ $100\muM$ IAA, $100\muM$ $Cd^{2+}$+ $100\muM$ IAA + 2 mM sucrose) for 3 weeks and then the effects of indole acetic acid (IAA) on the accumulation of $Cd^{2+}$ and growth of $Cd^{2+}$-treated Commelina were investigated. In the treatment of $Cd^{2+}$, $Cd^{2+}$ was uptaked to 1.74, and 51.36 ${\mu}g/g$ frwt. at the first week, but for three weeks, 0.51 and 34,53 ${\mu}g/g$ frwt, in leaf and stem respectively. When IAA was treated along with $Cd^{2+}$, $Cd^{2+}$ was uptaked to 0.18 and 8.63 ${\mu}g/g$ fiwt, at the first week, and for the incubation of 3 weeks, 0,51 and 45.0 ${\mu}g/g$ fiwt. in leaf and stem. In case of $Cd^{2+}$+IAA+sucrose, $Cd^{2+}$ was uptaked to 1.45 and 18.33 ${\mu}g/g$ frwt. at the first week, but for 3 weeks, 0,51 and 25.45 ${\mu}g/g$ fiwt. in leaf and stem. Likewise $Cd^{2+}$ uptake, the growth was also affected by $Cd^{2+}$ and IAA. During the incubation of 3 weeks, $Cd^{2+}$ reduced the stem growth about 8% in all weeks, but the treatment of IAA recovered the inhibition of stem growth caused by $Cd^{2+}$ to the degree of the control Therefore, it could be concluded that IAA altered the pattern of $Cd^{2+}$ uptake and the growth which were supposed to change $Cd^{2+}$ toxicity.

• Journal of the Korean institute of surface engineering
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• v.57 no.4
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• pp.265-273
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• 2024

An amperometric sensor for measuring indole-3-acetic acid (IAA) was studied based on a screen-printed carbon electrode (SPCE) coated with a reduced graphene oxide composite electrocatalyst. The PEI-GO dispersion is uniformly formed through a nucleophilic substitution reaction between the active amine group of Polyethyleneimine (PEI) and the epoxide group exposed on the surface of graphene oxide. And The 3-dimensional PEI-rGO AG (Polyethyleneimine-reduced graphene oxide aerogel) complex was easily prepared through simple heat treatment of the combined PEI-GO dispersion. The proposed composite catalyst electrode, PEI-rGO AG/SPCE, showed a two linear relationship in the low and high concentrations in IAA detection, and the linear equation was I_pa = 0.2883C + 0.0883 (R²=0.9230) at low concentration and Ipa = 0.00464C + 0.6623 (R²=0.9894) at high concentration was proposed, and the detection limit was calculated to be 203.5nM±33.2nM. These results showed the applicability of the PEI-rGO AG composite catalyst as an electrode material for electrocatalysts for the detection of IAA.

• Journal of Microbiology and Biotechnology
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• v.28 no.9
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• pp.1511-1516
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• 2018

In this study, we investigated Indole-3-acetic acid (IAA) production by a rice phylloplane bacteria, Enterobacter sp. DMKU-RP206, using sweet whey as a feed stock instead of lactose. We succeeded in using sweet whey for Enterobacter sp. DMKU-RP206 to produce 3,963.0 mg IAA/l with the optimal medium containing 1.48% sweet whey, 1.42% yeast extract and 0.88% $\text\tiny{L}$-tryptophan. The medium pH was adjusted to 6 and the culture conditions were shaking at 200 rpm on an orbital shaker at $30^{\circ}C$ for 3 days. We also evaluated the effect of IAA in culture filtrates of Enterobacter sp. DMKU-RP206 on the promotion of jasmine rice growth in a pot experiment. Compared with the negative control (without IAA), the result showed that biosynthetic IAA produced by Enterobacter sp. DMKU-RP206 significantly increased the growth of jasmine rice (Oryza sativa L. cv. KDML105) in terms of length and dry weight of shoot. This work thus reveals the impact of IAA produced by Enterobacter sp. on the promotion of jasmine rice growth.

• Journal of Microbiology and Biotechnology
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• v.20 no.9
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• pp.1259-1265
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• 2010

The filamentous cyanobacterium Arthrospira platensis strain MMG-9 was isolated from a rice field. The ability of this strain to synthesize the bioactive compound indole-3-acetic acid (IAA) was demonstrated. IAA was extracted from the culture of A. platensis strain MMG-9 and its identity was confirmed by thin-layer chromatography (TLC) as well as by high-performance liquid chromatography (HPLC). The IAA precursor L-tryptophan was required for IAA biosynthesis. Released IAA increased with the increase of the initial concentration of L-tryptophan in the medium and with the incubation time. A. platensis strain MMG-9 accumulated more IAA than it released into the medium. The bioactivity of the secreted IAA was shown by its effect on the formation of roots by Pisum sativum. There was a significant positive effect of the supernatant of cultures of A. platensis strain MMG-9 on the number of lateral roots of P. sativum, whereas a negative effect on root length was observed.