Stabilization of Hydroxy-α-Sanshool by Antioxidants Present in the Genus Zanthoxylum.

Japanese pepper (sansho, Zanthoxylum piperitum) contains several types of sanshools belonging to N-alkylamides. Because of the long-chain unsaturated fatty acids present in their structure, sanshools are prone to oxidative deterioration, which poses problems in processing. In this paper, we evaluated the effects of antioxidants from the genus Zanthoxylum in preventing sanshool degradation using accelerated tests. An ethanolic extract of segment membranes of the sansho fruit pericarp was incubated at 70 °C for 7 days with different antioxidants to determine the residual amount of hydroxy-α-sanshool (HαS) in the extract. α-Tocopherol (α-Toc) showed excellent HαS-stabilizing activity at low concentrations. Among phenolic acids, we noted that the HαS-stabilizing activity increased with the number of hydroxy groups per molecule. For example, gallic acid and its derivatives exhibited excellent sanshool-stabilizing activity. Quercetin was found to be a superior HαS stabilizer compared with hesperetin and naringenin. However, the effective concentration was much higher for phenolic compounds than for α-Toc. These substances are believed to play a role in preventing the decomposition of sanshools in the pericarp of sansho. These sanshool stabilizers should be useful in the development of new beverages, foods, cosmetics, and pharmaceuticals that take advantage of the taste and flavor of sansho.

Infused juice concentrate of Japanese plum Prunus mume attenuates inflammatory vascular remodeling in a mouse model of hypertension induced by angiotensin II.

Fruit from the Prunus mume tree is a traditional food in Japan. Recently, bainiku-ekisu, an infused juice concentrate of Japanese Prunus mume, is attracting attention as a health promoting supplement. Angiotensin II (Ang II) plays a central role in development of hypertension. It has been reported that bainiku-ekisu treatment attenuates the growth-promoting signaling induced by Ang II in vascular smooth muscle cells. However, whether bainiku-ekisu has any effect on an animal model of hypertension remains unknown. Therefore, this study was designed to explore the potential anti-hypertensive benefit of bainiku-ekisu utilizing a mouse model of hypertension with Ang II infusion. Male C57BL/6 mice were infused with Ang II for 2 weeks and given 0.1% bainiku-ekisu containing water or normal water for 2 weeks with blood pressure evaluation. After 2 weeks, mice were euthanized, and the aortas were collected for evaluation of remodeling. Aortic medial hypertrophy was observed in control mice after Ang II infusion, which was attenuated in bainiku-ekisu group with Ang II infusion. Bainiku-ekisu further attenuated aortic induction of collagen producing cells and immune cell infiltration. Development of hypertension induced by Ang II was also prevented by bainiku-ekisu. Echocardiograph indicated protection of Ang II-induced cardiac hypertrophy by bainiku-ekisu. In vascular fibroblasts, bainiku-ekisu attenuated vascular cell adhesion molecule-1 induction, an endoplasmic reticulum stress marker, inositol requiring enzyme-1α phosphorylation, and enhancement in glucose consumption in response to Ang II. In conclusion, Bainiku-ekisu prevented Ang II-induced hypertension and inflammatory vascular remodeling. Potential cardiovascular health benefit to taking bainiku-ekisu should be further studied.

Traditional Japanese apricot (Prunus mume) induces osteocalcin in osteoblasts.

The fruit of Prunus mume (ume, also known as Japanese apricot) has been used as a functional food in Japan since ancient times. We previously reported that ume stimulates the differentiation of preosteoblastic cells. Osteocalcin (OCN) is secreted by osteoblasts, and there is known association with glucolipid metabolism and cognitive function. This study sought to clarify the relationship between ume extracts and OCN production both in vitro and in vivo. Alkaline phosphatase activity and OCN level in the ethyl acetate extracts of ume-treated extracts were significantly increased in preosteoblast MC3T3-E1 cells compared with the control group. In human study, serum OCN level was significantly higher in the high ume intake group than in the low intake group in community-dwelling participants over 60 years old. These results suggest that ume has the potential to upregulated OCN production both in vitro and in vivo.

Enrichment of marine manganese-oxidizing microorganisms using polycaprolactone as a solid organic substrate.

OBJECTIVE: Heterotrophic manganese (Mn)-oxidizing microorganisms responsible for biogenic manganese oxide (Bio-MnOx) production are fastidious. Their enrichment is not easily accomplished by merely adding a soluble organic substrate to non-sterile mixed cultures. The objective of this study was to evaluate polycaprolactone (PCL), an aliphatic polyester, as an effective solid organic substrate for the enrichment of marine Mn-oxidizing microorganisms. RESULTS: We successfully obtained marine microbial enrichment with the capacity for dissolved Mn removal and MnOx production using PCL as a solid organic substrate. The removal of dissolved Mn by the Mn-oxidizing enrichment culture followed first-order kinetics with a rate constant of 0.014 h-1. 16S rRNA gene amplicon sequencing analysis revealed that the Mn-oxidizing enrichment culture was highly dominated by operational taxonomic units related to the bacterial phyla Cyanobacteria, Planctomycetes, and Proteobacteria. CONCLUSIONS: Our data demonstrate that PCL can serve as a potential substrate to enrich Mn-oxidizing microorganisms with the ability to produce MnOx under marine conditions.

Two Japanese pepper (Zanthoxylum piperitum) fruit-derived compounds attenuate IgE-mediated allergic response in vitro and in vivo via inhibition of mast cell degranulation.

Zanthoxylum piperitum (ZP, 'Japanese pepper') is a traditional medicine and pepper used in Asian countries such as Japan. Hydroxy-α-sanshool, a pungent-tasting substance contained within ZP, has been reported to slightly suppress immunoglobulin E (IgE)-mediated mast cell degranulation. The current study aims to newly identify anti-allergic compounds derived from ZP. We examine the inhibitory mechanisms behind IgE-mediated mast cell degranulation. By inhibitory effect-guided isolation, we identified degranulation inhibitory compounds derived from ZP fruit: 1-acetoxy-7-hydroxy-3, 7-dimethylocta-2E, 5E-diene (ZP1) and 8-hydroxygeranyl acetate (ZP2). ZP1 and ZP2 inhibited IgE-mediated degranulation and A23187-mediated degranulation in RBL-2H3 mast cells. Our findings suggest the inhibition of degranulation by ZP1 and ZP2 was by inhibition of Lyn phosphorylation, followed by inhibition of intracellular Ca2+ mobilization, protein kinase C alpha phosphorylation, membrane ruffling, and granule-to-plasma membrane fusion. Oral administration of ZP1 or ZP2 attenuated an IgE-mediated passive cutaneous anaphylactic reaction in mice. Histological observation suggests that this effect occurred via inhibition of mast cell degranulation. These findings indicate that ZP1 and ZP2 attenuate allergic reaction via inhibition of IgE-mediated mast cell degranulation.

Bioactivation mechanisms of N-hydroxyaristolactams: Nitroreduction metabolites of aristolochic acids.

Aristolochic acids (AAs) are human nephrotoxins and carcinogens found in concoctions of Aristolochia plants used in traditional medicinal practices worldwide. Genotoxicity of AAs is associated with the formation of active species catalyzed by metabolic enzymes, the full repertoire of which is unknown. Recently, we provided evidence that sulfonation is important for bioactivation of AAs. Here, we employ Salmonella typhimurium umu tester strains expressing human N-acetyltransferases (NATs) and sulfotransferases (SULTs), to study the role of conjugation reactions in the genotoxicities of N-hydroxyaristolactams (AL-I-NOH and AL-II-NOH), metabolites of AA-I and AA-II. Both N-hydroxyaristolactams show stronger genotoxic effects in umu strains expressing human NAT1 and NAT2, than in the parent strain. Additionally, AL-I-NOH displays increased genotoxicity in strains expressing human SULT1A1 and SULT1A2, whereas AL-II-NOH shows enhanced genotoxicity in SULT1A1/2 and SULT1A3 strains. 2,6-Dichloro-4-nitrophenol, SULTs inhibitor, reduced umuC gene expression induced by N-hydroxyaristolactams in SULT1A2 strain. N-hydroxyaristolactams are also mutagenic in parent strains, suggesting that an additional mechanism(s) may contribute to their genotoxicities. Accordingly, using putative SULT substrates and inhibitors, we found that cytosols obtained from human kidney HK-2 cells activate N-hydroxyaristolactams in aristolactam-DNA adducts with the limited involvement of SULTs. Removal of low-molecular-weight reactants in the 3.5-10 kDa range inhibits the formation of aristolactam-DNA by 500-fold, which could not be prevented by the addition of cofactors for SULTs and NATs. In conclusion, our results demonstrate that the genotoxicities of N-hydroxyaristolactams depend on the cell type and involve not only sulfonation but also N,O-acetyltransfer and an additional yet unknown mechanism(s). Environ. Mol. Mutagen. 2019. © 2019 Wiley Periodicals, Inc.

Antimutagenic activity of flavonoids from Sozuku.

Pinocembrin (1) and cardamonin (2) from Sozuku showed a suppressive effect on umu gene expression of SOS response in Salmonella typhimurium TA1535/pSK1002 against the mutagen furylfuramide. Compounds 1 and 2 suppressed 52% and 36% of SOS-inducing activity at a concentration of 0.20 µmol/mL. The ID50 value of 1 was 0.18 µmol/mL. These compounds showed the suppression of 2-amino-3,4-dimethylimidazo-[4,5-f]quinolone (MeIQ) and UV irradiation-induced SOS response. Pinostrobin (3) and 5,7-dimethoxyflavanone (4), methyl ethers of 1, showed similar activity to 1 against MeIQ-induced SOS response, but that of furylfuramide and UV irradiation were decreased. On the other hand, compounds 1-4 did not show the suppression of activated MeIQ-induced SOS response. Furthermore, compounds 1-4 showed potent antimutagenic activity against MeIQ mutagenesis in Ames test using the S. typhimurium TA100 and TA98 strains.

Biotransformation of (+)-isofraxinellone by Aspergillus niger and insect antifeedant activity.

The biotransformation of (+)-isofraxinellone (1) by Aspergillus niger was investigated. Compound 1 was transformed to only one new compound 2. The structure of 2 was identified as (-)-(4S)-4-hydroxyisofraxinellone which was regio- and stereo-selective hydroxylated at the C-4 position by IR, EI-MS 1D and 2D NMR. Absolute configuration of hydroxyl group at the C-4 position was detected by modified Mosher's method. Antifeedant activity of compounds 1 and 2 against larvae of Spodoptera litura was assayed. These compounds showed potent antifeedant activity and ED50 (50% of effective dose) values were 3.91 and 4.43 µg/cm2, respectively.

Biotransformation of (+)-Carvone and (-)-Carvone by the Common Cutworm Spodoptera litura Larvae.

Biotransformation of (+)- and (-)-carvone (1 and 2) by the larvae of common cutworm (Spodoptera litura) has been investigated. (+)-Carvone was transformed to (+)-(4S)-10-hydroxycarvone (1-1), (+)-(4S)-7- hydroxycarvone (1-2), and (-)-(4S)-8,9-dihydroxy-8,9-dihydrocarvone (1-3). (-)-Carvone (2) was transformed to (-)-(4R)-10-hydroxycarvone (2-1), (-)-(4R)-7-hydroxycarvone (2-2), (+)-(4R)-8,9-dihydroxy-8,9- dihydrocarvone (2-3), and (-)-(2R,4R)-10-hydroxycarveol (2-4). The results indicate that the main metabolic reaction of carvones by S. litura larvae is oxidation at vinyl group (C-8 and C-9).

Biological and epidemiological evidence of anti-allergic effects of traditional Japanese food ume (Prunus mume).

Japanese apricot (Prunus mume; ume) is a traditional food in Japan that has been shown to have various beneficial health effects. There is some evidence to suggest that ume is also effective against allergic disease. Here, we conducted a cross-sectional epidemiological pilot study to examine the association between ume intake frequency and allergic symptoms including rhinitis in 563 adults (288 men and 275 women) who resided in Wakayama, Japan. After adjusting for age, present illness and medication, women with high ume intake had significantly lower odds ratio (OR) for the presence of symptoms of allergy [OR: 0.49 with 95% confidence interval (CI): 0.25-0.97]. Therefore, we investigated the anti-allergic effect of ume on passive cutaneous anaphylaxis (PCA) reaction in immunoglobulin E (IgE)-sensitized mice. The animal study demonstrated that oral administration of ume extract attenuated the PCA reaction and mast cell degranulation. Furthermore, RBL-2H3 mast cells were used to identify anti-allergic ume compounds. The following ume compounds inhibited IgE-mediated mast cell degranulation: vanillin, syringic acid, protocatechuic aldehyde, lyoniresinol and p-coumaric acid. These results suggested that ume has the potential to inhibit mast cell degranulation and may be associated with reduced risk of allergic symptoms in women.

Comparison of Essential Oils from Three Kinds of Cryptotaenia japonica Hassk (Kirimitsuba, Nemitsuba, and Itomitsuba) used in Japanese Food.

The compositions of the essential oils from three kinds of Cryptotaenia japonica Hassk ("Mitsuba" in Japanese, Kirimitsuba (KM), Nemitsuba (NM), and Itomitsuba (IM)) were investigated by capillary GC/GC-MS. The oils contained 53 volatile components, of which 95% were terpenoids. The major constituents were sesquiterpenoids, which were α-selinene (KM: 39.1%; NM: 38.4%; IM: 13.2%), ß-selinene (15.5%, 15.2%, 4.8%), germacrene D (12.1%, 7.2%, 24.1%), trans-farnesene (11.1%, 6.0%, 10.9%), ß-elemene (2.9%, 2.9%, 6.8%), and trans-caryophyllene (1.7%, 1.7%, 2.6%). The main sesquiterpene found in KM and NM was α-selinene and in IM was germacrene D. The major monoterpenes found were ß-myrcene (3.8%, 6.7%, and 3.5%) and ß-pinene (2.8%, 0.2%, and 1.4%).

Biotransformation of (-)-(1R,4S)-Menthone and (+)-(1S,4R)-Menthone by the Common Cutworm Spodoptera litura Larvae.

Using biotransformation as a biocatalytic process has the advantage of being able to proceed under mild conditions and with high regio- and enantioselectivity. This study investigated the biotransformation of (-)-(1R,4S)-menthone (1) and (+)-(1S,4R)-menthone (2) by Spodoptera litura larvae. Compound 1 was converted to (-)-(1R,4S)-7-hydroxymenthone (1-1), (+)-(1R,3S,4S)-7-hydroxyneomenthol (1-2) and (-)-(1R,4S,8R)-p-menth-3-one-9-oic acid (1-3). The metabolism of substrate 2 generated three enantiomers of the above metabolites, designated as 2-1 to 2-3, respectively. The C-9 position of (-)-menthone and (+)-menthone was oxidized to carboxylic acid by S. litura, which is a metabolic pathway not observed in any other example of biocatalysis.

Inhibition of ß-Secretase Activity by Monoterpenes, Sesquiterpenes, and C13 Norisoprenoids.

Inhibition of ß-secretase (BACE1) is currently regarded as the leading treatment strategy for Alzheimer's disease. In the present study, we aimed to screen the in vitro inhibitory activity of 80 types of aroma compounds (monoterpenes, sesquiterpenes, and C13 norisoprenoids), including plant-based types, at a 200-µM concentration against a recombinant human BACE1. The results showed that the most potent inhibitor of BACE1 was geranyl acetone followed by (+)-camphor, (-)-fenchone, (+)-fenchone, and (-)-camphor with the half-maximal inhibitory concentration (IC50) values of 51.9 ± 3.9, 95.9 ± 11.0, 106.3 ± 14.9, 117.0 ± 18.6, and 134.1 ± 16.4 µM, respectively. Furthermore, the mechanism of inhibition of BACE1 by geranyl acetone was analyzed using Dixon kinetics plus Cornish-Bowden plots, which revealed mixed-type mode. Therefore aroma compounds may be used as potential lead molecules for designing anti-BACE1 agents.

In Vitro Regio- and Stereoselective Oxidation of ß-Ionone by Human Liver Microsomes.

The metabolism of the norisoprenoid ß-ionone was investigated in vitro using human liver microsomes and 11 different recombinant cytochrome P450 enzymes expressed in Trichoplusia ni cells. ß-Ionone was found to be oxidized via 4S-hydroxylation by CYP2B6 in human liver microsomes. CYP1A2 also regioselectively catalyzed the hydroxylation of ß-ionone to yield 4-hydroxylation; this conversion was not stereoselective. Further kinetic analysis revealed that CYP2B6 exhibited the highest activity for ß-ionone 4-hydroxylation. Kinetic analysis showed that Km and Vmax for oxidation of ß-ionone by CYP1A2 and CYP2B6 was 107.9 ± 36.0 µM and 3200.3 ± 323.0 nmol/min/nmol P450 and 5.6 ± 1.2 µM and 572.8 ± 29.8 nmol/min/nmol P450, respectively. The reaction rates observed using human liver microsomes and recombinant CYP2B6 were very high compared with those of other CYP2B6 substrates reported thus far. These results suggest that ß-ionone, a norisoprenoid present in nature, is one of the effective substrates for CYP2B enzymes in human liver microsomes. To the best of our knowledge, this is the first time that 4-hydroxy ß-ionone has been described as a human metabolite of ß-ionone.

Biodegradation of high concentrations of formaldehyde by lyophilized cells of Methylobacterium sp. FD1.

In the present study, Methylobacterium sp. FD1 utilizing formaldehyde was isolated from soil. The resting cells of FD1 degraded high concentrations of formaldehyde (~2.7 M) and produced formic acid and methanol that were molar equivalents of one-half of the degraded formaldehyde. This result suggests that formaldehyde degradation by FD1 is caused by formaldehyde dismutase. The optimal temperature and pH for formaldehyde degradation by the resting cells of FD1 were 40 °C and 5-7, respectively. The lyophilized cells of FD1 also degraded high concentrations of formaldehyde. The formaldehyde degradation activity of the lyophilized cells was maintained as the initial activity at 25 °C for 287 days. These results suggest that the lyophilized cells of FD1 are useful as formaldehyde degradation materials.

3,4-Dihydroxybenzaldehyde Derived from Prunus mume Seed Inhibits Oxidative Stress and Enhances Estradiol Secretion in Human Ovarian Granulosa Tumor Cells.

Granulosa cells form ovarian follicles and play important roles in the growth and maturation of oocytes. The protection of granulosa cells from cellular injury caused by oxidative stress is an effective therapy for female infertility. We here investigated an effective bioactive compound derived from Prunus mume seed extract that protects granulosa cells from hydrogen peroxide (H2O2)-induced apoptosis. We detected the bioactive compound, 3,4-dihydroxybenzaldehyde (3,4-DHBA), via bioactivity-guided isolation and found that it inhibited the H2O2-induced apoptosis of granulosa cells. We also showed that 3,4-DHBA promoted estradiol secretion in granulosa cells and enhanced the mRNA expression levels of steroidogenic factor 1, a promoter of key steroidogenic enzymes. These results suggest that P. mume seed extract may have clinical potential for the prevention and treatment of female infertility.

Characteristic odorants from bailingu oyster mushroom (Pleurotus eryngii var. tuoliensis) and summer oyster mushroom (Pleurotus cystidiosus).

In this study, the characteristic odorants of the volatile oils from Pleurotus species (P. eryngii var. tuoliensis and P. cystidiosus) were extracted by hydrodistillation and analyzed by gas chromatography-mass spectrometry (GC-MS), gas chromatography-olfactometry (GC-O), and aroma extract dilution analysis (AEDA). A total of 52 and 54 components (P. eryngii var. tuoliensis and P. cystidiosus, respectively) were identified, representing about 98.8% and 85.1% of the volatile oils, respectively. The main components of the P. eryngii var. tuoliensis oil were palmitic acid (82, 38.0%), oleic acid (86, 25.0%) and linoleic acid (85, 9.7%). The main components of the P. cystidiosus oil, palmitic acid (82, 25.8%), indole (54, 9.1%) and myristic acid (77, 5.3%). Regarding the aroma components, 16 and 13 components were identified in the P. eryngii var. tuoliensis and P. cystidiosus oils respectively, by the GC-O analyses. The results of the sniffing test, odor activity value (OAV) and flavor dilution (FD) factor indicate that methional, 1-octen-3-ol and nonanal are the main aroma-active components of P. eryngii var. tuoliensis oil. On the other hands, dimethyl trisulfide and 1-octen-3-ol were estimated as the main aroma-active components of the P. cystidiosus oil.

Chemical composition, aroma evaluation, and oxygen radical absorbance capacity of volatile oil extracted from Brassica rapa cv. "yukina" used in Japanese traditional food.

The chemical composition of the volatile oil extracted from the aerial parts of Brassica rapa cv. "yukina" was analyzed using GC-MS, GC-PFPD, and GC-O. A total of 50 compounds were identified. The most prominent constituents were (E)-1,5-heptadiene (40.27%), 3-methyl-3-butenenitrile (25.97%) and 3-phenylpropanenitrile (12.41%). With regard to aroma compounds, 12 compounds were identified by GC-O analysis. The main aroma-active compounds were dimethyl tetrasulfide (sulphury-cabbage, FD = 64), 3-phenylpropanenitrile (nutty, FD = 64), 3-methylindole (pungent, FD = 64), and methional (potato, FD = 32). The antioxidant activity of the aroma-active compounds of the oil was determined using an oxygen radical absorbance capacity (ORAC) assay using fluorescein as the fluorescent probe. The ORAC values were found to be 785 ± 67 trolox equivalents (µmol TE/g) for B. rapa cv. "yukina" oil. The results obtained showed that the volatile oil extracted from the aerial parts is a good dietary source of antioxidants.

Peach (Prunus persica) extract inhibits angiotensin II-induced signal transduction in vascular smooth muscle cells.

Angiotensin II (Ang II) is a vasoactive hormone that has been implicated in cardiovascular diseases. Here, the effect of peach, Prunus persica L. Batsch, pulp extract on Ang II-induced intracellular Ca(2+) mobilization, reactive oxygen species (ROS) production and signal transduction events in cultured vascular smooth muscle cells (VSMCs) was investigated. Pretreatment of peach ethyl acetate extract inhibited Ang II-induced intracellular Ca(2+) elevation in VSMCs. Furthermore, Ang II-induced ROS generation, essential for signal transduction events, was diminished by the peach ethyl acetate extract. The peach ethyl acetate extract also attenuated the Ang II-induced phosphorylation of epidermal growth factor receptor and myosin phosphatase target subunit 1, both of which are associated with atherosclerosis and hypertension. These results suggest that peach ethyl acetate extract may have clinical potential for preventing cardiovascular diseases by interfering with Ang II-induced intracellular Ca(2+) elevation, the generation of ROS, and then blocking signal transduction events.

A Prunus mume extract stimulated the proliferation and differentiation of osteoblastic MC3T3-E1 cells.

Osteoporosis is a serious disease caused by decreased bone mass. There is constant matrix remodeling in bones, by which bone formation is performed by osteoblastic cells, whereas bone resorption is accomplished by osteoclast cells. We investigated the effect of a Japanese apricot (Prunus mume SIBE. et ZUCC.) extract on the proliferation and osteoblastic differentiation in pre-osteoblastic MC3T3-E1 cells. An alkaline phosphatase (ALP) activity assay, cell proliferation assay, alizarin red staining and expression analysis of osteoblastic genes were carried out to assess the proliferation and osteoblastic differentiation. The water-soluble fraction of Prunus mume (PWF) increased the ALP activity, cell proliferation and mineralization. The gene expression of osteopontin and bone morphogenetic protein-2, which are markers in the early period of osteoblastic differentiation, were significantly enhanced by the PWF treatment. PWF therefore stimulated the proliferation and osteoblastic differentiation of cells and may have potential to prevent osteoporosis.