Synthesis of a New Glycoconjugate with Di-á´ -Psicose Anhydride Structure.

Demand for healthy diets has led researchers to explore new saccharide as sucrose alternatives. ᴅ-Psicose, the C-3 epimer of ᴅ-fructose, has a similar sweetness intensity to sucrose but contributes fewer calories. This study proposes a disaccharide with a stable structure derived from ᴅ-psicose. The compound with a spiro-tricyclic core was generated at 32% conversion via caramelization of ᴅ-psicose under acidic anhydrous conditions. The compound was identified by high-resolution mass spectrometry and multi-dimensional nuclear magnetic resonance (NMR). The molecular formula was established as C12H20O10 from the molecular weight of m/z 324.1055. Twelve signals were observed by the 13C NMR spectrum. This compound, denoted di-ᴅ-psicose anhydride (DPA), exhibited a lower water solubility (40 g/L) and higher thermal stability (peak temperature = 194.7 °C) than that of ᴅ-psicose (peak temperature = 126.5 °C). The quantitatively evaluated metal ion scavenging ability of DPA was the best in magnesium (average 98.6 ± 1.1%). This synthesis methodology can provide disaccharides with high stability-reducing heavy metals.

Three New Phthalide Glycosides from the Rhizomes of Cnidium officinale and Their Recovery Effect on Damaged Otic Hair Cells in Zebrafish.

The extract from Cnidium officinale rhizomes was shown in a prior experiment to markedly recover otic hair cells in zebrafish damaged by neomycin. The current study was brought about to identify the principal metabolite. Column chromatography using octadecyl SiO2 and SiO2 was performed to isolate the major metabolites from the active fraction. The chemical structures were resolved on the basis of spectroscopic data, including NMR, IR, MS, and circular dichroism (CD) data. The isolated phthalide glycosides were assessed for their recovery effect on damaged otic hair cells in neomycin-treated zebrafish. Three new phthalide glycosides were isolated, and their chemical structures, including stereochemical characteristics, were determined. Two glycosides (0.1 µM) showed a recovery effect (p < 0.01) on otic hair cells in zebrafish affected by neomycin ototoxicity. Repeated column chromatography led to the isolation of three new phthalide glycosides, named ligusticosides C (1), D (2), and E (3). Ligusticoside C and ligusticoside E recovered damaged otic hair cells in zebrafish.

Aurones and Flavonols from Coreopsis lanceolata L. Flowers and Their Anti-Oxidant, Pro-Inflammatory Inhibition Effects, and Recovery Effects on Alloxan-Induced Pancreatic Islets in Zebrafish.

(1) Background: Many flavonoids have been reported to exhibit pharmacological activity; a preparatory study confirmed that Coreopsis lanceolata flowers (CLFs) contained high flavonoid structure content; (2) Methods: CLFs were extracted in aqueous methanol (MeOH:H2O = 4:1) and fractionated into acetic ester (EtOAc), normal butanol (n-BuOH), and H2O fractions. Repeated column chromatographies for two fractions led to the isolation of two aurones and two flavonols; (3) Results: Four flavonoids were identified based on a variety of spectroscopic data analyses to be leptosidin (1), leptosin (2), isoquercetin (3), and astragalin (4), respectively. This is the first report for isolation of 2-4 from CLFs. High-performance liquid chromatography (HPLC) analysis determined the content levels of compounds 1-4 in the MeOH extract to be 2.8 ± 0.3 mg/g (1), 17.9 ± 0.9 mg/g (2), 3.0 ± 0.2 mg/g (3), and 10.9 ± 0.9 mg/g (4), respectively. All isolated compounds showed radical scavenging activities and recovery activities in Caco-2, RAW264.7, PC-12, and HepG2 cells against reactive oxygen species. MeOH extract, EtOAc fraction, and 1-3 suppressed NO formation in LPS-stimulated RAW 264.7 cells and decreased iNOS and COX-2 expression. Furthermore, all compounds recovered the pancreatic islets damaged by alloxan treatment in zebrafish; (4) Conclusions: The outcome proposes 1-4 to serve as components of CLFs in standardizing anti-oxidant, pro-inflammatory inhibition, and potential anti-diabetic agents.

Syringoleosides A-H, Secoiridoids from Syringa dilatata Flowers and Their Inhibition of NO Production in LPS-Induced RAW 264.7 Cells.

Repeated column chromatography of Syringa dilatata flowers, a native shrub to Korea, led to the isolation of eight new oleoside-type secoiridoids, syringoleosides A-H (1-8), as well as five known secoiridoids (9-13). The new chemical structures were identified through spectroscopic data analysis, as well as the application of chemical methods. Compounds 1, 2, 6, 7, 11, and 13 showed suppression effects on NO production in LPS-induced RAW 264.7 cells, with IC50 values ranging from 32.5 ± 9.8 to 65.7 ± 11.0 µM, and no visible toxicity. The content of the major secoiridoids in S. dilatata flowers, compounds 1, 4, 5, 8, 9, 12, and 13, were determined through HPLC analysis.

LC-MS-Based Lipidomic Analysis of Serum Samples from Spontaneously Hypertensive Rats Treated with an Extract of Acanthopanax sessiliflorus Fruits.

Recently, lipidomics has revealed that many diseases are highly associated with altered lipid metabolism, as in the case of hypertension affecting serum lipid metabolism. In this study, an LC-MS-based lipidomic approach was used to profile serum lipids in spontaneously hypertensive rats (SHRs) treated with an extract of Acanthopanax sessiliflorus fruits (ASF), to elucidate the serum lipid metabolism alteration by hypertension and the treatment of a drug or ASF. First, UPLC-QTOF/MS profiled a total of 208 lipids from six pooled samples of normal controls, SHR, SHR + 100 mg/kg of drug, and SHR + ASF 200, 400, or 600 mg/kg. These six groups were differentiated by the PCA and sPLS-DA, and 120 lipid species were identified as differentially regulated lipids (DRLs) by ANOVA (p values < 0.05). Second, UPLC-QqQ/MS was used for the target profiling of 120 DRLs from individual samples of the six groups. Using an ANOVA, 67 lipids (38 TGs, 4 DGs, 17 PCs, 2 PEs, and 6 LPCs) were selected as validated DRLs. The mostly altered lipids, such as TG (62:13), TG (60:13), PC (34:4), PC (36:5), and PC (38:2), were decreased in SHR compared to the normal control, and received little by treatment with ASF. These results demonstrated the correlation between hypertension and serum lipid metabolism. Furthermore, both drug and ASF treatment similarly altered the lipid profiles of SHRs. Finally, we found that DRLs have the potential to help us to interpret the lipid metabolism of hypertension.

6-Methoxyflavonols from the aerial parts of Tetragonia tetragonoides (Pall.) Kuntze and their anti-inflammatory activity.

Dried aerial parts of Tetragonia tetragonoides were extracted with 70% EtOH, and the evaporated residue was successively separated into EtOAc, n-BuOH, and H2O fractions. As a result of repeated SiO2, ODS, and Sephadex LH-20 column chromatography, four new 6-methoxyflavonol glycosides (2-4, 8) along with four known ones (1, 5-7) were isolated. Several spectroscopic data led to determination of chemical structures for four new 6-methoxyflavonol glycosides (2-4, 8) and four known ones, 6-methoxykaempferol 3-O-ß-d-glucopyranosyl-(1 → 2)-ß-d-glucopyranosyl-7-O-(6‴'-(E)-caffeoyl)-ß-d-glucopyranoside (1), 6-methoxyquercetin (5), 6-methoxykaempferol (6), and 6-methoxykaempferol 7-O-ß-d-glucopyranoside (7). Methoxyflavonol glycosides 2-8 also have never been reported from T. tetragonoides in this study. 6-Methoxyflavonols 5 and 6 showed high radical scavenging potential in DPPH and ABTS test. Also, all compounds showed significant anti-inflammatory activities such as reduction of NO and PGE2 formation and suppression of TNF-α, IL-6, IL-1ß, iNOS, and COX-2 expression in LPS-stimulated RAW 264.7 macrophages. In general, the aglycones exhibited higher activity than the glycosides. In addition, quantitative analysis of 6-methoxyflavonols in the T. tetragonoides aerial parts extract was conducted through HPLC.

Lanceoleins A-G, hydroxychalcones, from the flowers of Coreopsis lanceolata and their chemopreventive effects against human colon cancer cells.

Seven new chalcones, lanceolein A-G (compounds 5 and 7-12), as well as five known chalcones (1-4 and 6), were isolated from the methanolic extract of Coreopsis lanceolata flowers. The chemical structures of 5 and 7-12 were determined on the basis of spectroscopic data interpretation. All compounds inhibited the production of nitrite oxide (NO) induced by LPS in RAW264.7 macrophage cells. Also, compounds 1-6 showed moderated cytotoxicity against human colon cancer cell lines, while compounds 7-12 hardly showed the cytotoxicity. Especially, compounds 2, 5, and 6 exhibited a little higher cytotoxicity on HCT15 cells, with IC50 values of 43.7 ±â€¯2.17 µM, 35.6 ±â€¯0.24 µM, and 47.9 ±â€¯1.18 µM, respectively. In the Tali assay, compounds 2 and 5 increased the numeral of apoptotic cells. These compounds also significantly promoted the expression of apoptotic proteins including PARP and caspase-3.

Flavonoids from Chionanthus retusus (Oleaceae) Flowers and Their Protective Effects against Glutamate-Induced Cell Toxicity in HT22 Cells.

The dried flowers of Chionanthus retusus were extracted with 80% MeOH, and the concentrate was divided into EtOAc, n-BuOH, and H2O fractions. Repeated SiO2, octadecyl SiO2 (ODS), and Sephadex LH-20 column chromatography of the EtOAc fraction led to the isolation of four flavonols (1-4), three flavones (5-7), four flavanonols (8-11), and one flavanone (12), which were identified based on extensive analysis of various spectroscopic data. Flavonoids 4-6 and 8-11 were isolated from the flowers of C. retusus for the first time in this study. Flavonoids 1, 2, 5, 6, 8, and 10-12 significantly inhibited NO production in RAW 264.7 cells stimulated by lipopolysaccharide (LPS) and glutamate-induced cell toxicity and effectively increased HO-1 protein expression in mouse hippocampal HT22 cells. Flavonoids with significant neuroprotective activity were also found to recover oxidative-stress-induced cell damage by increasing HO-1 protein expression. This article demonstrates that flavonoids from C. retusus flowers have significant potential as therapeutic materials in inflammation and neurodisease.

Glycosyl glycerides from the aerial parts of Malva verticillata and their chemopreventive effects.

A new glycosyl glyceride (5) along with twelve known ones (1-4 and 6-13) including two sulfoquinovosyl glycerides (1 and 2) were isolated from the aerial parts of Malva verticillata. Based on several spectroscopic methods, compound 5 was identified to be (2S)-1-O-ß-d-galactopyranosyl-3-O-isostearoyl glyceride, and named malvaglycolipid A. Compounds 1 and 2 contained a unique sugar, (6-deoxy-6-sulfo)-α-d-glucopyranose, which very rarely occurs in natural sources. This is the first report for the isolation of compounds 1 and 2 from natural sources and the structure determination using NMR experiment. It was also of note that no glycosyl glyceride has previously been isolated from the family of Malvaeae. Most glycosyl glycerides showed cytotoxicity to HepG2, AGS, HCT-15, and A549 human cancer cells. Especially, compounds 1, 2, and 11 exhibited significant cytotoxicity to AGS cells, with IC50 values of 33.7 ±â€¯0.64 µM, 11.1 ±â€¯0.07 µM, and 10.6 ±â€¯0.10 µM, respectively. The n-BuOH fraction and compounds 1, 2, and 11 increased the number of apoptotic cells in the Tali assay and had a significant effect on the levels of proteins related to apoptosis including PARP, caspase-3, Bcl-2, Bax, and ß-actin.

New Lignans from the Flower of Forsythia koreana and Their Suppression Effect on VCAM-1 Expression in MOVAS Cells.

Six lignans including two new lignans were obtained as the principal components of the Forsythia koreana flowers via silica gel (SiO2 ), octadecyl SiO2 (ODS) as well as Sephadex LH-20 column chromatography. In addition to two new lignans, named koreanaside A ((7R,8S,7'R,8'S)-7,7'-diepoxy-5'-hydroxy-3,3'-dimethoxylignan 4-O-ß-d-glucopyranoside) and koreanaside B ((7R,8S,7'S,8'R)-7,9'-epoxy-9,5',7'-trihydroxy-3,3'-dimethoxylignan 4-O-ß-d-glucopyranoside), four known lignans were identified to be (+)-phylligenin, (-)-epipinoresinol, pinoresinol, and tinosposide A. The structures and absolute configurations of koreanasides A and B were established by means of analysis of spectroscopic data (NMR, IR, FAB-MS, and CD), whereas the structures of known lignans were identified by comparison their NMR and MS values with those in the reported literature. Their chemical structures including configuration were established by means of analysis of spectroscopic data (NMR, IR, FAB-MS, and CD) but also comparison of their NMR and MS values with those in the reported literature. This is the first article for isolation of six lignans of F. koreana flowers. Koreanasides A and B showed high radical scavenging activity with oxygen radical absorbance capacity (ORAC) values of 0.97 ± 0.01 and 1.02 ± 0.01, respectively. Koreanaside A also prohibited expressing VCAM-1 in MOVAS cells with 80.5% at 25 mg/mL.

Flavonoid 8-O-Glucuronides from the Aerial Parts of Malva verticillata and Their Recovery Effects on Alloxan-Induced Pancreatic Islets in Zebrafish.

Malva verticillata (Cluster mallow), a leafy vegetable that has been popular in East Asia for a long time, has also been used in herbal teas and medicines. The aqueous fraction of the aerial parts of Malva verticillata, exhibiting a very high quantity of flavonoids compared to the EtOAc and n-BuOH fractions, exhibited significant recovery effects on pancreatic islets damaged by alloxan in zebrafish larvae. Thus, the bioactive components responsible for this anti-diabetic activity were investigated. A new flavonoid glucuronide (1) and five known flavonoids were isolated from the aqueous fraction. Based on several spectroscopic methods, compound 1 was identified to be nortangeretin-8-O-ß-D-glucuronide, and was named malvaflavone A. The A-ring of compound 1 had a 5,6,7,8-tetrahydroxy moiety, which rarely occurs in plant systems. Also 8-O-glucuronide attached to the flavonoid moiety was rarely occurred in plant system. Compounds 1, 3, 4, and 6 significantly improved the pancreatic islet size in zebrafish at 0.1 µM, and compounds 1 and 6 were found to block ß-cell K⁺ channels in experiments with diazoxide. In ABTS, ORAC, and SOD assays, compounds 1-5 exhibited high anti-oxidant activities compared with quercetin and BHA (positive controls), indicating that the 8-O-glucuronide attached to the flavonoid moiety is a key structure for the expression of anti-oxidant activity. This is the first report of the isolation of compounds 1-6 from M. verticillata as well evaluated for anti-diabetic and anti-oxidant ativities.

Isolation and Quantification of Ginsenoside Rh23, a New Anti-Melanogenic Compound from the Leaves of Panax ginseng.

A new ginsenoside, named ginsenoside Rh23 (1), and 20-O-ß-d-glucopyranosyl-3ß,6α,12ß,20ß,25-pentahydroxydammar-23-ene (2) were isolated from the leaves of hydroponic Panax ginseng. Compounds were isolated by various column chromatography and their structures were determined based on spectroscopic methods, including high resolution quadrupole/time of flight mass spectrometry (HR-QTOF/MS), nuclear magnetic resonance (NMR) spectroscopy, and infrared (IR) spectroscopy. To determine anti-melanogenic activity, the change in the melanin content in melan-a cells treated with identified compounds was tested. Additionally, we investigated the melanin inhibitory effects of ginsenoside Rh23 on pigmentation in a zebrafish in vivo model. Compound 1 inhibited potent melanogenesis in melan-a cells with 37.0% melanogenesis inhibition at 80 µM and also presented inhibition on the body pigmentation in zebrafish model. Although compound 2 showed slightly lower inhibitory activity than compound 1, it also showed significantly decreased melanogenesis in melan-a cell and in zebrafish model. These results indicated that compounds isolated from hydroponic P. ginseng may be used as new skin whitening compound through the in vitro and in vivo systems. Furthermore, this study demonstrated the utility of MS-based compound 1 for the quantitative analysis. Ginsenoside Rh23 (1) was found at a level of 0.31 mg/g in leaves of hydroponic P. ginseng.

UPLC-QTOF/MS-Based Metabolomics Applied for the Quality Evaluation of Four Processed Panax ginseng Products.

In the food industry and herbal markets, it is critical to control the quality of processed Panax ginseng products. In this study, ultra-performance liquid chromatography coupled to quadrupole time of flight mass spectrometry (UPLC-QTOF/MS)-based metabolomics was applied for the quality evaluation of white ginseng (WG), tae-geuk ginseng (TG), red ginseng (RG), and black ginseng (BG). Diverse metabolites including ginsenosides were profiled by UPLC-QTOF/MS, and the datasets of WG, TG, RG, and BG were then subjected to multivariate analyses. In principal component analysis (PCA), four processed ginseng products were well-differentiated, and several ginsenosides were identified as major components of each product. S-plot also characterized the metabolic changes between two processed ginseng products, and the major ginsenosides of each product were found as follows: WG (M-Rb1, M-Rb2, M-Rc, Re, Rg1), TG (Rb2, Rc, Rd, Re, Rg1), RG (Rb1, Rb2, Rc, Rd, Re, Rg1), and BG (Rd, Rk1, Rg5, Rg3). Furthermore, the quantitative contents of ginsenosides were evaluated from the four processed ginseng products. Finally, it was indicated that the proposed metabolomics approach was useful for the quality evaluation and control of processed ginseng products.

Metabolic differences in Zingiber officinale Roscoe by geographical origin determined via multiplatform metabolomics and method for simultaneous analysis of six phenolic compounds.

Ginger, which is the rhizome of Zingiber officinale Roscoe, is widely distributed and consumed. The taste and aroma of ginger differ depending on its geographical origin. To distinguish the origin of ginger, ginger extracts from Korea, Peru, and China were analyzed using ultra-performance liquid chromatography (UPLC) coupled to quadrupole time-of-flight mass spectrometry and nuclear magnetic resonance spectroscopy for metabolomics. Korean ginger contained more 10-gingerol, and Peruvian ginger contained more 6-gingerol and 8-gingerol. Several amino acids negatively correlated with gingerols, suggesting that amino acids are related to the biosynthesis of gingerols. Sugars, which are the main energy source, positively correlated with gingerols. Organic acids and gingerols were also positively correlated, indicating that both organic acids and gingerols are used for adaptation to the environment surrounding the root. We confirmed the features of the primary and secondary metabolites by verifying the correlation between metabolites and differences in metabolites according to ginger origin. We additionally optimized a simultaneous UPLC analytical method of marker compounds for the simple and rapid quality control of ginger. This method exhibits excellent linearity, sensitivity, and reproducibility. Using metabolomics, differences in origin were observed, and a low-end equipment analysis method for quality control can be used in the ginger industry.

Trapping mechanism by di-d-psicose anhydride with methylglyoxal for prevention of diabetic nephropathy.

Di-d-psicose anhydride (DPA), derived from functional rare saccharide as d-psicose, is investigated for its strong chelating ability. Methylglyoxal (MGO), an important precursor of advanced glycation end-products (AGEs), promotes obesity, and causes complications such as diabetic nephropathy. On mesangial cells, DPA can substantially reduce the negative effects of MGO. DPA effectively trapping MGO in mesangial cells. The bonding properties of the DPA-MGO adduct were discussed by mass spectrometry and nuclear magnetic resonance (NMR). The NMR spectra of the DPA-MGO adduct provide evidence for chelation bonding. The inhibition of AGE formation and the mass spectrometry results of the DPA-MGO adduct indicate that DPA can scavenge MGO at a molar ratio of 1:1. DPA suppressed 330 % of the up-regulated receptor for an AGEs protein expression to a normal level and restored the suppressed glyoxalase 1 level to 86 % of the normal group. This research provides important evidence and theoretical basis for the development of AGE inhibitors derived from rare saccharide.

Synthesis of Alpha-Linked Glucosides from Soybean Isoflavone Aglycones Using Amylosucrase from Deinococcus geothermalis.

Soybean isoflavone aglycones (SIAs) have many biological activities but are poorly water-soluble in the human body. Glycosylation provides structural diversity to SIAs and can alter their physicochemical properties, including water solubility. An alpha-linked glucosylation of SIA was achieved using amylosucrase from Deinococcus geothermalis. A total of 13 alpha-linked glucosyl SIAs were obtained, and their colors in solution were confirmed. The structures of the isolated compounds were identified by mass spectrometry and multidimensional nuclear magnetic resonance spectroscopy. The amylosucrase transglycosylation formed new isoflavone glycosides with alpha glycosidic bonds at C-7 and/or C-4' of SIAs, followed by the production of isoflavone glycosides with alpha (1 → 6) glycosidic bonds. The products with a glucosyl moiety attached to the C-4' of SIAs were found to be more water-soluble than their counterparts attached to the C-7 and/or beta-linkages. This study suggests a strategy for the synthesis of bioactive compounds with enhanced water solubility through alpha-linked glucosylation.

Steppogenin suppresses tumor growth and sprouting angiogenesis through inhibition of HIF-1α in tumors and DLL4 activity in the endothelium.

BACKGROUND: Hypoxia is a characteristic feature of many solid tumors. As an adaptive response to hypoxia, tumor cells activate hypoxia-inducible factor-1α (HIF-1α). Under hypoxic conditions, angiogenesis mediated by HIF-1α is involved in the growth and metastasis of tumor cells. During the angiogenic process, differentiated tip endothelial cells (ECs) characterized by high expression of DLL4 promote angiogenic germination through filopodia. Inhibitors of HIF-1α or DLL4 have been widely studied PURPOSE: We tried to find inhibitors targeting both HIF-1α and DLL4 in tumor which have not yet been developed. STUDY DESIGN: In this study, we examined a natural compound that inhibits sprouting angiogenesis and tumor growth by targeting both HIF-1α and DLL4 under hypoxic conditions. METHODS: After examining cell viability of 70 selected natural compounds, we assessed the effects of compounds on HIF-1α and DLL4 transcriptional activity using a dual-luciferase reporter assay. Western blot analysis, immunofluoresecnt assay and real-time qPCR were performed to identify expression of proteins, such as HIF-1α and DLL4, as well as HIF-1α target genes under hypoxic conditions. In vitro angiogenesis assay and in vivo allograft tumor experiment were performed to investigate inhibition of tumor growth through anti-angiogenic activity. RESULTS: Among these compounds, steppogenin, which is extracted from the root bark of Morus alba l, respectively inhibited the transcriptional activity of HIF-1α under hypoxic conditions in HEK293T cells and vascular endothelial growth factor (VEGF)-induced DLL4 expression in vascular ECs in a dose-dependent manner. In tumor cells and retinal pigment epithelial cells, steppogenin significantly suppressed HIF-1α protein levels under hypoxic conditions as well as VEGF-induced DLL4 expression in ECs. Furthermore, steppogenin suppressed hypoxia-induced vascular EC proliferation and migration as well as VEGF-induced sprouting of EC spheroids. CONCLUSION: These results suggest that the natural compound steppogenin could potentially be used to treat angiogenic diseases, such as those involving solid tumors, because of its dual inhibition of HIF-1α and DLL4.

Phenylalkyl Glycosides from the Flowers of Brugmansia arborea L. and Their Radical Scavenging Effect and Protective Effect on Pancreatic Islets Damaged by Alloxan in Zebrafish (Danio rerio) Larvae.

The study aimed to investigate the antioxidant and antidiabetic activity of Brugmansia arborea L. flower extracts, solvent fractions, and isolated compounds. B. arborea L flowers were extracted with aqueous methanol, and concentrated extract was successively partitioned into EtOAc, n-BuOH, and H2O fractions. Repeated silica gel and octadecyl silica gel column chromatographies for EtOAc and n-BuOH fractions led to the isolation of a new phenylalkyl glycoside (6), along with five known ones. Several spectroscopic data led to the structure determination of one new phenylalky glycoside as brugmansioside C (named) (6) and five known ones as benzyl-O-ß-D-glucopyranoside (1), benzyl-O-ß-D-glucosyl-(1→6)-ß-D-glucopyranoside (2), 2-phenylethyl-O-ß-D-glucopyranoside (3), 2-phenylethyl-O-ß-D-glucosyl-(1→6)-ß-D-glucopyranoside (4), and 3-phenylpropyl-O-ß-D-glucopyranoside (5). The five known ones (1-5) were isolated from B. arborea flowers for the first time in this study. The extract, solvent fractions, and all isolated compounds showed radical scavenging activities using ABTS radical, and EtOAc fraction showed the highest scavenging capacity, whereas compounds 2, 4, and 6 did not display the capacity to use the DPPH radical. The extract, solvent fractions, and all isolated compounds showed a protective effect on pancreatic islets damaged by alloxan treatment in zebrafish larvae. The pancreatic islet size treated with EtOAc, n-BuOH fractions, and all compounds significantly increased by 64.0%, 69.4%, 82.0%, 89.8%, 80.0%, 97.8%, 103.1%, and 99.6%, respectively, compared to the alloxan-induced group. These results indicate that B. arborea flowers and their isolated compounds are useful as potential antioxidant and antidiabetic agents.

Optimization of accelerated solvent extraction of ellagitannins in black raspberry seeds using artificial neural network coupled with genetic algorithm.

This study aimed to identify ellagitannins in black raspberry seeds (BRS) and to optimize accelerated solvent extraction of ellagitannins using an artificial neural network (ANN) coupled with genetic algorithm. Fifteen monomeric and dimeric ellagitannins were identified in BRS. For ANN modeling, extraction time, extraction temperature, and solvent concentration were set as input variables, and total ellagitannin content was set as output variable. The trained ANN had a mean squared error value of 0.0102 and a regression correlation coefficient of 0.9988. The predicted optimal extraction conditions for maximum total ellagitannin content were 63.7% acetone, 4.21 min, and 43.9 °C. The actual total ellagitannin content under the optimal extraction conditions was 13.4 ± 0.0 mg/g dry weight, and the prediction error was 0.75 ± 0.27%. This study is the first attempt to analyze the composition of ellagitannins in BRS and to determine optimal extraction conditions for maximum total ellagitannin content from BRS.

In Vitro and In Vivo Antibacterial Activity of Serratamid, a Novel Peptide-Polyketide Antibiotic Isolated from Serratia plymuthica C1, against Phytopathogenic Bacteria.

A new hybrid non-ribosomal peptide-polyketide antibiotic (serratamid) for phytoprotection was isolated from the ethyl acetate layer of tryptic soy agar culture of the soil bacterium Serratia plymuthica C1 through bioassay-guided fractionation. Its chemical structure was elucidated using instrumental analyses, such as mass and nuclear magnetic resonance spectrometry. Serratamid showed antibacterial activity against 15 phytopathogenic bacteria, with minimum inhibitory concentration (MIC) values ranging from 0.244 to 31.25 µg/mL. In vitro, it displayed strong antibacterial activity against Ralstonia solanacearum and four Xanthomonas spp., with MIC values (0.244-0.488 µg/mL) superior to those of streptomycin sulfate, oxolinic acid, and oxytetracycline. Further, serratamid and the ethyl acetate layer of S. plymuthica C1 effectively reduced bacterial wilt caused by R. solanacearum on tomato seedlings and fire blight caused by Erwinia on apple fruits in a dose-dependent manner. These results suggest that serratamid is a promising candidate as a potent bactericide for controlling bacterial diseases.