Solid-state cultivation of multiple industrial strains of koji mold on different Thai unpolished rice cultivars: biotransformation of phenolic compounds and their effects on antioxidant activity.

Colored rice is abundant in polyphenols, and koji molds have potential for biotransformation. This study aimed to produce Thai-colored rice koji to study its polyphenolic biotransformation. Four industrial koji mold strains: Aspergillus oryzae 6001, A.

New analogs of pochonicine, a potent β--acetylglucosaminidase inhibitor from fungus var. TAMA 87.

Three novel analogs of pochonicine () were isolated from a solid fermentation culture of the fungal strain var. TAMA 87, and their structures were elucidated as 7-deoxypochonicine (), 6-deoxypochonicine (), and 6,7-dideoxypochonicine (). These analogs were found to possess the same stereochemistry as pochonicine.

Aerobic bioconversion of C-glycoside mangiferin into its aglycone norathyriol by an isolated mouse intestinal bacterium.

Norathyriol is an aglycone of a xanthonoid C-glycoside mangiferin that possesses different bioactive properties useful for humans compared to mangiferin. Mangiferin is more readily available in nature than norathyriol; thus, efficient mangiferin conversion into norathyriol is desirable. There are a few reports regarding mangiferin C-deglycosylation because of the C-C bond resistance toward acid, alkaline, and enzyme hydrolysis.

A new asteltoxin analog with insecticidal activity from TAMA 87.

A new asteltoxin analog, named asteltoxin H (), was isolated by the solid-state fermentation of the fungus var. TAMA 87. The chemical structure of was deduced by spectroscopic methods, including 1D and 2D NMR, HRESIMS, and UV-Vis analyses.

Convenient preparation of an antigenic oligosaccharide from white kidney bean powder: A useful plant oligosaccharide for synthesis of immunoactive glycopolymer.

Plant glycoproteins, especially allergenic glycoproteins such as pollen allergens, often carry antigenic N-glycans with α1-3 fucose and/or β1-2 xylose residue(s) on the trimannosyl core structure. We previously reported that one of such antigenic free-form N-glycans, Man3Xyl1Fuc1GlcNAc2 (M3FX) suppressed IL-4 production from Th2 cells of pollinosis patients. For the molecular-level analysis of this immunoactivity, an effective and convenient procedure for large scale preparation of the immunoactive free-form N-glycan and a synthesis of glycopolymers bearing multivalent M3FX has been required.

Use of wood vinegar to enhance 5-aminolevulinic acid production by selected in rubber sheet wastewater for agricultural use.

This study aimed to produce inexpensive 5-aminolevulinic acid (ALA) in a non-sterile latex rubber sheet wastewater (RSW) by TN114 and PP803 for the possibility to use in agricultural purposes by investigating the optimum conditions, and applying of wood vinegar (WV) as an economical source of levulinic acid to enhance ALA content. The Box-Behnken Design experiment was conducted under microaerobic-light conditions for 96 h with TN114, PP803 and their mixed culture (1:1) by varying initial pH, inoculum size (% v/v) and initial chemical oxygen demand (COD, mg/L). Results showed that the optimal condition (pH, % inoculum size, COD) of each set to produce extracellular ALA was found at 7.

Unique antimicrobial spectrum of ophiobolin K produced by Aspergillus ustus.

A co-cultivation study of two fungal strains showed that Aspergillus ustus could inhibit Aspergillus repens growth. The bioactive compound responsible for the observed activity was purified and identified as a sesterterpene, ophiobolin K. Ophiobolin K exhibited marked inhibition against both fungi and bacteria, especially A.

Characterization of exopolymeric substances from selected Rhodopseudomonas palustris strains and their ability to adsorb sodium ions.

Removal of Na(+) by binding with exopolymeric substances (EPS) from Rhodopseudomonas palustris TN114 and PP803 was investigated. The moderate negative correlation pairs (rp) between remaining Alcian blue and amount of Na(+) adsorbed on EPS from strains TN114 and PP803 were -0.652 and -0.

Synthesis of eight stereoisomers of pochonicine: nanomolar inhibition of β-N-acetylhexosaminidases.

Pochonicine, the first naturally occurring polyhydroxylated pyrrolizidine containing an acetamidomethyl group, which was isolated from Pochonia suchlasporia var. suchlasporia TAMA 87, together with its enantiomer and their C-1 and/or C-3 epimers, have been synthesized from the sugar-derived cyclic nitrones 9D and 9L, respectively. An in-depth NMR study showed that both the (1)H and (13)C NMR spectra of the synthetic pochonicines (1D and 1L) matched very well with those of natural pochonicine in D2O, which unequivocally determined the relative configuration of the natural product as 1D or 1L.

TMG-chitotriomycin as a probe for the prediction of substrate specificity of β-N-acetylhexosaminidases.

TMG-chitotriomycin (1) produced by the actinomycete Streptomyces annulatus NBRC13369 was examined as a probe for the prediction of substrate specificity of β-N-acetylhexosaminidases (HexNAcases). According to the results of inhibition assays, 14 GH20 HexNAcases from various organisms were divided into 1-sensitive and 1-insensitive enzymes. Three representatives of each group were investigated for their substrate specificity.

Melanogenesis inhibitors from Rabdosia japonica.

The effects of the four major ent-kaurene diterpenoids isolated from the aerial part of Rabdosia japonica (Labiatae) on murine B16-F10 melanoma cells were investigated. Among the compounds tested, oridonin and nodosin most significantly suppressed cellular melanin production when the cells were cultured with these diterpenoids. However, oridonin and nodosin exhibited cytotoxicity against the same melanoma cells with an IC(50) of 1.

MS/MS fragmentation-guided search of TMG-chitooligomycins and their structure-activity relationship in specific β-N-acetylglucosaminidase inhibition.

The reducing tetrasaccharide TMG-chitotriomycin (1) is an inhibitor of β-N-acetylglucosaminidase (GlcNAcase), produced by the actinomycete Streptomyces anulatus NBRC13369. The inhibitor shows a unique inhibitory spectrum, that is, selectivity toward enzymes from chitin-containing organisms such as insects and fungi. Nevertheless, its structure-selectivity relationship remains to be clarified.

Peptide bond formation by aminolysin-A catalysis: a simple approach to enzymatic synthesis of diverse short oligopeptides and biologically active puromycins.

A new S9 family aminopeptidase derived from the actinobacterial thermophile Acidothermus cellulolyticus was cloned and engineered into a transaminopeptidase by site-directed mutagenesis of catalytic Ser(491) into Cys. The engineered biocatalyst, designated aminolysin-A, can catalyze the formation of peptide bonds to give linear homo-oligopeptides, hetero-dipeptides, and cyclic dipeptides using cost-effective substrates in a one-pot reaction. Aminolysin-A can recognize several C-terminal-modified amino acids, including the l- and d-forms, as acyl donors as well as free amines, including amino acids and puromycin aminonucleoside, as acyl acceptors.

Multifunctional cytotoxic agents from Anacardium occidentale.

The effects of anacardic acids and cardols isolated from the cashew nut and apple Anacardium occidentale (Anacardiaceae) on murine B16-F10 melanoma cells were tested. Although anacardic acids and cardols were found to inhibit tyrosinase, a key enzyme in melanin synthesis, melanogenesis in melanocytes was not suppressed in cultured cells but rather enhanced. Both anacardic acids and cardols exhibited moderate cytotoxicity.

Pochonicine, a polyhydroxylated pyrrolizidine alkaloid from fungus Pochonia suchlasporia var. suchlasporia TAMA 87 as a potent beta-N-acetylglucosaminidase inhibitor.

A new polyhydroxylated pyrrolizidine alkaloid designated as pochonicine (1) was isolated from a solid fermentation culture of the fungal strain Pochonia suchlasporia var. suchlasporia TAMA 87. The structure of 1 was determined using NMR and MS techniques as (1R*, 3S*, 5S*, 6S*, 7R*, 7a S*)-5-acetamidomethyl-3-hydroxymethyl-1,6,7-trihydroxypyrrolizidine.

Effects of phenolic compounds isolated from Rabdosia japonica on B16-F10 melanoma cells.

Pedalitin isolated from the aerial part of Rabdosia japonica (Labiatae), exhibited cytotoxicity against the murine B16-F10 melanoma cell line with an IC(50) of 30 microm (9.5 microg/mL). As the cells were cultured with this flavone, melanin production was not suppressed, but rather enhanced.

Effects of cuminaldehyde on melanoma cells.

Cuminaldehyde (4-isopropylbenzaldehyde) suppressed melanin formation in cultured murine B16-F10 melanoma cells in a dose-dependent decrease up to 0.25 mm without affecting cell growth. Approximately 30% suppression in melanin production resulted when the cells were cultured with 0.

Antinematodal activities of ingenane diterpenes from Euphorbia kansui and their derivatives against the pine wood nematode (Bursaphelenchus xylophilus).

Under the bioassay-guided method, two diterpenes, 3-O-(2",3"-dimethylbutanoyl)-13-O-dodecanoylingenol (1) and 3-O-(2",3"-dimethylbutanoyl)-13-O-decanoylingenol (2) isolated from Euphorbia kansui, showed a pronounced antinematodal activity against the nematode Bursaphelenchus xylophilus at the same minimum effective dose (MED) of 5 microg per cotton ball and still displayed antinematodal activity at a dose of 2.5 microg per cotton ball. Compounds 3-6 were obtained, and the structure of the new compound 6 was elucidated based on 1D- and 2D-NMR analyses and physicochemical data.

Repellent from traditional Chinese medicine, Periploca sepium Bunge.

By using a new bioassay-guided method, 2-hydroxy-4-methoxybenzaldehyde isolated from the root bark of Periploca sepium, a traditional Chinese medicine, showed repellent activity against the olive weevil (Dyscerus perforatus) at 62.5, 125, 250 and 500 microg/disc, respectively. In addition, it also exhibited antinematodal activity against Bursaphelenchus xylophilus at a minimum effective dose of 200 microg/ball.

Effects of quercetin on mushroom tyrosinase and B16-F10 melanoma cells.

In searching for tyrosinase inhibitors from plants using L-3,4-dihydroxyphenylalanine (L-DOPA) as a substrate, quercetin was found to be partially oxidized to the corresponding o-quinone under catalysis by mushroom tyrosinase (EC 1.14.18.

Effects of salicylic acid on mushroom tyrosinase and B16 melanoma cells.

Salicylic acid slightly inhibited the oxidation of L-3,4-dihydroxyphenylalanine (L-DOPA) catalyzed by mushroom tyrosinase noncompetitively without being oxidized. In contrast, 4-hydroxybenzoic acid did not inhibit this enzymatic oxidation if a longer reaction time was observed, although it suppressed the initial rate of the oxidation to a certain extent. Neither acid showed noticeable effects on cultured murine B16-F10 melanoma cells except weak cytotoxicity.

Anisaldehyde, a melanogenesis potentiator.

Anisaldehyde (4-methoxybenzaldehyde), previously reported as a tyrosinase inhibitor, did not inhibit melanogenesis in cultured B16-F10 melanoma cells but rather enhanced it. This adverse effect of anisaldehyde was accompanied by melanocytotoxicity in a dose-dependent manner up to 2 mM. The melanin content per cell at 1 mM was increased 5-fold compared to control and morphological observations showed the deposition of melanin pigments.

Three antinematodal diterpenes from Euphorbia kansui.

Three compounds, 20-O-acetyl-[3-O-(2'E,4'Z)-decadienoyl]-ingenol (1), 20-O-acetyl-[5-O-(2'E,4'Z)-decadienoyl]-ingenol (2) and 3-O-(2'E,4'Z)-decadienoylingenol (3), were isolated from Euphorbia kansui under the bioassay-guided method. Each compound showed the same antinematodal activity against the nematode, Bursaphelenchus xylophilus, at a minimum effective dose (MED) of 5 microg/cotton ball.