Total flavonoids of Broussonetia papyrifera alleviate non-alcohol fatty liver disease via regulating Nrf2/AMPK/mTOR signaling pathways

BACKGROUNDS

Non-alcoholic fatty liver disease (NAFLD) is one of the most prevalent chronic liver diseases. The leaves of Broussonetia papyrifera contain a large number of flavonoids, which have a variety of biological functions.

METHODS

In vitro experiments, free fatty acids were used to stimulate HepG2 cells. NAFLD model was established in vivo in mice fed with high fat diet (HFD) or intraperitoneally injected with Tyloxapol (Ty). At the same time, Total flavonoids of Broussonetia papyrifera (TFBP) was used to interfere with HepG2 cells or mice.

RESULTS

The results showed that TFBP significantly decreased the lipid accumulation induced by oil acid (OA) with palmitic acid (PA) in HepG2 cells. TFBP decreased the total cholesterol (TC), the triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), and increased high-density lipoprotein cholesterol (HDLC) in serum. TFBP could also effectively inhibit the generation of reactive oxygen species (ROS) and restrained the level of myeloperoxidase (MPO), and enhance the activity of superoxide dismutase (SOD) to alleviate the injury from oxidative stress in the liver. Additionally, TFBP activated nuclear factor erythroid-2-related factor 2 (Nrf2) pathway to increasing the phosphorylation of AMP-activated protein kinase (AMPK). Meanwhile, protein levels of mTORC signaling pathway were evidently restrained with the treatment of TFBP.

CONCLUSION

Our experiments proved that TFBP has the therapeutic effect in NAFLD, and the activation of Nrf2 and AMPK signaling pathways should make sense.

Protective effect of Broussonetia papyrifera leaf polysaccharides on intestinal integrity in a rat model of diet-induced oxidative stress

This study aimed to investigate the effect of Broussonetia papyrifera polysaccharides (BPP) on the jejunal intestinal integrity of rats ingesting oxidized fish oil (OFO) induced oxidative stress. Polysaccharides (Mw 16,956 Da) containing carboxyl groups were extracted from Broussonetia papyrifera leaves. In vitro antioxidant assays showed that this polysaccharide possessed antioxidant capabilities. Thirty-two male weaned rats were allocated into two groups orally infused BPP solution and PBS for 26 days, respectively. From day 9 to day 26, half of the rats in each group were fed food containing OFO, where the lipid peroxidation can induce intestinal oxidative stress. OFO administration resulted in diarrhea, decreased growth performance (p < 0.01), impaired jejunal morphology (p < 0.05) and antioxidant capacity (p < 0.01), increased the levels of ROS and its related products, IL-1β and IL-17 (p < 0.01) of jejunum, as well as down-regulated Bcl-2/Bax (p < 0.01) and Nrf2 signaling (p < 0.01) of jejunum in rats. BPP gavage effectively alleviated the negative effects of OFO on growth performance, morphology, enterocyte apoptosis, antioxidant capacity and inflammation of jejunum (p < 0.05) in rats. In the oxidative stress model cell assay, the use of receptor inhibitors inhibited the enhancement of antioxidant capacity by BPP. These results suggested that BPP protected intestinal morphology, thus improving growth performance and reducing diarrhea in rats ingesting OFO. This protective effect may be attributed to scavenging free radicals and activating the Nrf2 pathway, which enhances antioxidant capacity, consequently reducing inflammation and mitigating intestinal cell death.

The Genus Broussonetia: An Updated Review of Phytochemistry, Pharmacology and Applications

The Broussonetia genus (Moraceae), recognized for its value in many Chinese traditional herbs, mainly includes Broussonetia papyrifera (L.) L’Hér. ex Vent. (BP), Broussonetia kazinoki Siebold (BK), and Broussonetia luzonica (Blanco) Bureau (BL). Hitherto, researchers have found 338 compounds isolated from BP, BK, and BL, which included flavonoids, polyphenols, phenylpropanoids, alkaloids, terpenoids, steroids, and others. Moreover, its active compounds and extracts have exhibited a variety of pharmacological effects such as antitumor, antioxidant, anti-inflammatory, antidiabetic, anti-obesity, antibacterial, and antiviral properties, and its use against skin wrinkles. In this review, the phytochemistry and pharmacology of Broussonetia are updated systematically, after its applications are first summarized. In addition, this review also discusses the limitations of investigations and the potential direction of Broussonetia. This review can help to further understand the phytochemistry, pharmacology, and other applications of Broussonetia, which paves the way for future research.

Microbial Transformation and Biological Activities of the Prenylated Aromatic Compounds from Broussonetia kazinoki

Broussonetia kazinoki has been used as a traditional medicine for the treatment of burns and acne, and its extracts have been found to show tyrosinase inhibitory and anticancer activities. In this study, the tyrosinase inhibitory and cytotoxic activities of B. kazinoki were explored, leading to the isolation of kazinol C (1), kazinol E (2), kazinol F (3), broussonol N (4), and kazinol X (5), of which the compounds 4 and 5 have not been previously reported. Microbial transformation has been recognized as an efficient tool to generate more active metabolites. Microbial transformation of the major compounds 1 and 3 was conducted with Mucor hiemalis, where four glucosylated metabolites (6-9) were produced from 1, while one hydroxylated (10) and one glucosylated (11) metabolites were obtained from 3. Structures of the isolated metabolites were determined by extensive spectroscopic analyses. All compounds were evaluated for their tyrosinase inhibitory and cytotoxic activities. Compound 3 and its metabolites, kazinol Y (10) and kazinol F-4″-O-β-d-glucopyranoside (11), exhibited the most potent tyrosinase inhibitory activities with the IC₅₀ values ranging from 0.71 to 3.36 µM. Meanwhile, none of the metabolites, except for kazinol C-2',3″-di-O-β-d-glucopyranoside (7), showed moderate cytotoxic activities (IC₅₀ 17.80 to 24.22 µM) against A375P, B16F10 and B16F1 cell lines.

Plastome phylogenomics of Allaeanthus, Broussonetia and Malaisia (Dorstenieae, Moraceae) and the origin of B. × kazinoki

Species of Broussonetia have been essential in the development of papermaking technology. In Japan and Korea, a hybrid between B. monoica and B. papyrifera (= B. × kazinoki) known as kōzo and daknamu is still the major source of raw materials for making traditional paper washi and hanji, respectively. Despite their cultural and practical significance, however, the origin and taxonomy of kōzo and daknamu remain controversial. Additionally, the long-held generic concept of Broussonetia s.l., which included Sect. Allaeanthus and Sect. Broussonetia, was challenged as phylogenetic analyses showed Malaisia is sister to the latter section. To re-examine the taxonomic proposition that recognizes Allaeanthus, Broussonetia, and Malaisia (i.e., Broussonetia alliance), plastome and nuclear ribosomal DNA (nrDNA) sequences of six species of the alliance were assembled. Characterized by the canonical quadripartite structure, genome alignments and contents of the six plastomes (160,121-162,594 bp) are highly conserved, except for the pseudogenization and/or loss of the rpl22 gene. Relationships of the Broussonetia alliance are identical between plastome and nrDNA trees, supporting the maintenance of Malaisia and the resurrection of Allaeanthus. The phylogenomic relationships also indicate that the monoecy in B. monoica is a derived state, possibly resulting from hybridization between the dioecious B. kaempferi (♀) and B. papyrifera (♂). Based on the hypervariable ndhF-rpl32 intergenic spacer selected by sliding window analysis, phylogeographic analysis indicates that B. monoica is the sole maternal parent of B. × kazinoki and that daknamu carries multiple haplotypes, while only one haplotype was detected in kōzo. Because hybridizations between B. monoica and B. papyrifera are unidirectional and have occurred rarely in nature, our data suggest that daknamu might have originated via deliberate hybrid breeding selected for making hanji in Korea. On the contrary, kōzo appears to have a single origin and the possibility of a Korean origin cannot be ruled out.

Broussoflavonol B from Broussonetia kazinoki Siebold Exerts Anti-Pancreatic Cancer Activity through Downregulating FoxM1

Pancreatic cancer has a high mortality rate due to poor rates of early diagnosis. One tumor suppressor gene in particular, p53, is frequently mutated in pancreatic cancer, and mutations in p53 can inactivate normal wild type p53 activity and increase expression of transcription factor forkhead box M1 (FoxM1). Overexpression of FoxM1 accelerates cellular proliferation and cancer progression. Therefore, inhibition of FoxM1 represents a therapeutic strategy for treating pancreatic cancer. Broussoflavonol B (BF-B), isolated from the stem bark of Broussonetia kazinoki Siebold has previously been shown to inhibit the growth of breast cancer cells. This study aimed to investigate whether BF-B exhibits anti-pancreatic cancer activity and if so, identify the underlying mechanism. BF-B reduced cell proliferation, induced cell cycle arrest, and inhibited cell migration and invasion of human pancreatic cancer PANC-1 cells (p53 mutated). Interestingly, BF-B down-regulated FoxM1 expression at both the mRNA and protein level. It also suppressed the expression of FoxM1 downstream target genes, such as cyclin D1, cyclin B1, and survivin. Cell cycle analysis showed that BF-B induced the arrest of G0/G1 phase. BF-B reduced the phosphorylation of extracellular signal-regulated kinase ½ (ERK½) and expression of ERK½ downstream effector c-Myc, which regulates cell proliferation. Furthermore, BF-B inhibited cell migration and invasion, which are downstream functional properties of FoxM1. These results suggested that BF-B could repress pancreatic cancer cell proliferation by inactivation of the ERK/c-Myc/FoxM1 signaling pathway. Broussoflavonol B from Broussonetia kazinoki Siebold may represent a novel chemo-therapeutic agent for pancreatic cancer.

Broussonetia papyrifera Root Bark Extract Exhibits Anti-inflammatory Effects on Adipose Tissue and Improves Insulin Sensitivity Potentially Via AMPK Activation

The chronic low-grade inflammation in adipose tissue plays a causal role in obesity-induced insulin resistance and its associated pathophysiological consequences. In this study, we investigated the effects of extracts of Broussonetia papyrifera root bark (PRE) and its bioactive components on inflammation and insulin sensitivity. PRE inhibited TNF-α-induced NF-κB transcriptional activity in the NF-κB luciferase assay and pro-inflammatory genes’ expression by blocking phosphorylation of IκB and NF-κB in 3T3-L1 adipocytes, which were mediated by activating AMPK. Ten-week-high fat diet (HFD)-fed C57BL6 male mice treated with PRE had improved glucose intolerance and decreased inflammation in adipose tissue, as indicated by reductions in NF-κB phosphorylation and pro-inflammatory genes’ expression. Furthermore, PRE activated AMP-activated protein kinase (AMPK) and reduced lipogenic genes’ expression in both adipose tissue and liver. Finally, we identified broussoflavonol B (BF) and kazinol J (KJ) as bioactive constituents to suppress pro-inflammatory responses via activating AMPK in 3T3-L1 adipocytes. Taken together, these results indicate the therapeutic potential of PRE, especially BF or KJ, in metabolic diseases such as obesity and type 2 diabetes.

Application of a stable carbon isotope for identifying Broussonetia papyrifera pollen

The objective of this study was to investigate whether δ¹³C values can be used to identify pollen specie in the atmosphere. A Burkard 7-day recording volumetric spore trap was used to collected pollens in the atmosphere in Tainan City, Taiwan, from January 2 to December 28, 2006, and a light microscope was used to identify the pollen species and concentrations. A Burkard cyclone sampler was used to collect particulate matter and an elemental analyzer with an isotope ratio mass spectrometer was used to analyze the δ¹³C values. Our data showed that the predominate pollen specie in the atmosphere was Broussonetia papyrifera pollen and that the annual average concentration was 27 grains/m³ (pollen season, 36; nonpollen season, 9 grains/m³). The average δ¹³C value was - 26.19‰ for particulate matter in the atmosphere (pollen season, - 26.00‰; nonpollen season, - 26.28‰). No significant association was observed between δ¹³C values and Broussonetia papyrifera pollen concentrations. However, the δ¹³C value in the atmosphere was associated with the levels of Broussonetia papyrifera pollen among the samples with a diameter of particulate matter smaller than 10 μm at a level lower than 40 μg/m³. In addition, the relative contribution of Broussonetia papyrifera pollen to the carbon in the atmosphere using a two end-member mixing models was found to be associated with the Broussonetia papyrifera pollen concentration. In summary, our study suggested that δ¹³C values can be applied in the assessment of Broussonetia papyrifera pollen specie under specific conditions in the atmosphere.

Biochar synthesized via pyrolysis of Broussonetia papyrifera leaves: mechanisms and potential applications for phosphate removal

In this study, Broussonetia papyrifera leaves collected from land near a restored manganese mine in the Hunan Province of China were converted into biochar under high-temperature anaerobic conditions, regeneration and utilization of agricultural and forest waste, and applied to the prevention of eutrophication. The physicochemical properties of the B. papyrifera biochar were characterized using Micromeritics 3Flex analyzer, scanning electron microscope (SEM), Fourier transform infrared spectrometer (FT-IR), thermogravimetric analyzer (TGA), X-ray photoelectron spectrometer (XPS), zeta potential meter (zeta), and X-ray diffraction (XRD). The effects of pH, ionic strength, coexisting ions, time, initial concentration, and temperature on the decontamination process of phosphate in water were studied. The results indicated that adsorption was enhanced under alkaline conditions. The pseudo-second-order model of adsorption kinetics was applied to illustrate the adsorption processes. The chemical adsorption reaction was the main rate-limiting step in the adsorption process. Isotherm experimental data were best fitted by the Freundlich model at 25 °C and by the Langmuir model at 35 °C. The phosphate combined with B. papyrifera biochar mainly in the forms of exchangeable phosphorus (Ex-P), Al-bound phosphorus (Al-P), and Fe-bound phosphorus (Fe-P). These results indicate that B. papyrifera biochar is a suitable candidate for the treatment of a eutrophic body of water.

Phytoextraction potential of Pteris vittata L. co-planted with woody species for As, Cd, Pb and Zn in contaminated soil

The objective of this study was to determine the phytoextraction potential of a hyperaccumulator co-planted with a large biomass of woody plant in metal(loid)-contaminated soil. A pot experiment was conducted for 270 days (d) to study the growth, physiological responses, and metal(loid)s accumulation characteristics of plants, which included a shade-requiring, As-hyperaccumulator perennial herb, Pteris vittata L., co-planted with a woody tree, namely Morus alba L. or Broussonetia papyrifera L., for soil contaminated with arsenic (As), cadmium (Cd), lead (Pb), and zinc (Zn). The results showed that the biomass, photosynthetic pigment contents, antioxidant enzyme activity, and uptake of As in P. vittata L. were significantly enhanced by co-planting with M. alba L. or B. papyrifera L. Especially, the uptake of As by P. vittata L. was significantly (p < 0.05) increased by 80.0% and 64.2% when it was co-planted with M. alba L. or B. papyrifera L., respectively, while the As, Cd, Pb, and Zn contents of both M. alba L. and B. papyrifera L. were not significantly promoted by the co-planting. The comprehensive phytoextraction of metal(loid)s could be optimized by the co-planting of P. vittata L. with M. alba L. or B. papyrifera L. The total amount of As in the shoots from co-planting species was significantly (p < 0.05) higher than that of the monoculture with M. alba L. or B. papyrifera L., and that of Cd and Zn in the shoots was significantly (p < 0.05) higher than that of the monoculture with P. vittata L. The results showed that the co-planting of P. vittata L. with M. alba L. or B. papyrifera L. can alleviate the toxic effects of metal(loid)s on plant growth and improve the comprehensive phytoextraction amounts of metal(loid)s, and is a promising strategy for remediation of metal(loid)-contaminated soil.

[Flavonoids with PTP1B inhibition from Broussonetia papyrifera]

Eleven flavonoids were isolated from the twigs of Broussonetia papyrifera by column chromatography over silica gel,ODS,MCI gel,and Sephadex LH-20,as well as RP-HPLC.Their structures were identified by spectroscopic methods including NMR,MS,UV,and IR as broupapyrin A(1),5,7,3',4'-tetrahydroxy-3-methoxy-8-geranylflavone(2),8-prenylquercetin-3-methyl ether(3),broussonol D(4),broussoflavonol B(5),uralenol(6),broussonol E(7),8-(1,1-dimethylallyl)-5'-(3-methylbut-2-enyl)-3',4',5,7-tetrahydroxyflanvonol(8),broussoflavonol E(9),4,2',4'-trihydroxychalcone(10),and butein(11).Compound 1 is a new isoprenylated flavonol.Compounds 3,6,10,and 11 were obtained from the genus Broussonetia for the first time,and 4 and 7 were firstly discovered in B.papyrifera.Compounds 1-5 and 7-9 showed significant inhibitory effects on PTP1 B with IC50 values ranging from(0.83±0.30) to(4.66±0.83) μmol·L-1.

Prenylated Polyphenols from Broussonetia kazinoki as Inhibitors of Nitric Oxide Production

Excessive nitric oxide (NO) production by macrophages has been involved in inflammatory diseases. Seven polyphenols (1–7) were isolated from Broussonetia kazinoki (B. kazinoki) and investigated as potential inhibitors of NO overproduction in lipopolysaccharide (LPS)-activated RAW 264.7 cells. Among them, four prenylated polyphenols (2–4 and 6) with a catechol moiety efficiently suppressed the LPS-induced high level of NO with IC₅₀ values of less than 6 µM. The compounds 2–4 and 6 also attenuated protein and mRNA levels of inducible nitric oxide synthase (iNOS). Moreover, they suppressed the nuclear factor κB (NF-κB) activity by inhibiting the degradation of inhibitory-κB-α (I-κB-α) and the translocation of NF-κB into the nucleus in LPS-activated macrophages. Taken together, these findings suggest that polyphenols from B. kazinoki might be beneficial for treatment of inflammatory diseases.

Bioengineered Osteoinductive Broussonetia kazinoki/Silk Fibroin Composite Scaffolds for Bone Tissue Regeneration

In this article, Broussonetia kazinoki (BK) powdery extract is utilized to modify the silk fibroin (SF) scaffold and applied to the bone defect area. The BK/SF scaffold is an efficient cell carrier which promotes cell proliferation and osteogenic differentiation of rBMSCs (bone marrow derived mesenchymal stem cells). We confirmed biocompatibility and osteogenic differentiation capacity of BK/SF scaffolds compared to pristine SF scaffold in both in vitro and in vivo evaluation. Gene expression related to osteogenic differentiation and bone regeneration significantly upregulated in the BK/SF scaffold group. The implanted scaffolds were attached well to the surface of the bone defect region and integrated with surrounding tissues without significant inflammatory reaction. Furthermore, almost 45% of bone volume has been recovered at 8 weeks postsurgery, while the SF and control group showed 20% recovery. These results suggest that BK powdery extract incorporated with an SF scaffold might be a suitable substitute for an alternative bone graft for bone regeneration.

Cytotoxic effects of kazinol A derived from Broussonetia papyrifera on human bladder cancer cells, T24 and T24R2

BACKGROUND

Broussonetia papyrifera (B. papyrifera), also known as paper mulberry, has been used as a traditional medicine for the treatment of several diseases, including ophthalmic disorders and impotency. However, the biological activity of kazinol A (1) among flavonols isolated from B. papyrifera has not been identified.

PURPOSE

We identified a candidate metabolite for anti-human bladder cancer treatment from B. papyrifera and investigated the possible molecular mechanisms underlying its cytotoxic effects in T24 and cisplatin-resistant T24R2 human bladder cancer cells.

METHODS

T24 and T24R2 cells were treated with five flavonols from B. papyrifera and their cytotoxic effects were determined using MTT assay, cell cycle analysis, mitochondrial membrane potential, and propidium iodide staining. Autophagy rate was calculated by counting LC3-GFP dots in the cells. All related protein expressions were analyzed by immunoblotting.

RESULTS

Compound 1 showed relatively higher cytotoxicity in the human bladder cancer cells, T24 and T24R2, rather than other tissues-originated cancer cells. Compound 1 significantly attenuated cell growth through G_0/1 arrest mediated by a decrease in cyclin D1 and an increase of p21. Apoptosis and autophagy induced by compound 1 treatment was accompanied by a modulation of the AKT-BAD pathway and AMPK-mTOR pathway, respectively.

CONCLUSIONS

Our results suggest that compound 1 induces cytotoxic effects in human bladder cancer cells, including the cisplatin-resistant T24R2. Compound 1 may be a candidate for the development of effective anti-cancer drug on human urinary bladder cancer.

Isolation and characterization of new phenolic compounds with estrogen biosynthesis-inhibiting and antioxidation activities from Broussonetia papyrifera leaves

Broussonetia papyrifera leaves (BPL) as a traditional Chinese medicine are also used in livestock feed for stimulating reproduction, adipose tissue and muscle development; however, the mechanism of their action is still unknown. Through estrogen biosynthesis-guided fractionation in human ovarian granulosa-like KGN cells, five new phenolic glycosides, broussoside A–E(1–5), along with fifteen known dietary phenolic compounds, were isolated from the n-butanol extract of BPL, and their structures were elucidated on the basis of NMR spectra analysis and chemical evidence. New compounds 3, 4, 5 and the known compounds 9 and 10 were found to potently inhibit estrogen biosynthesis in KGN cells. In addition, compounds 9, 17, 18, and 20 showed strong antioxidant activity against ABTS (2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt) and DPPH (1, 1′-diphenyl -2-picryl-hydrazyl radical) assays. These findings suggest that BPL may improve meat quality through the regulation of estrogen biosynthesis. Furthermore, they may be useful for the discovery of potential aromatase modulators from natural products. Finally, they could be considered as a new source for natural antioxidants.

Cytotoxic constituents from the leaves of Broussonetia papyrifera

AIM

To investigate the chemical constituents from the leaves of Broussonetia papyrifera.

METHODS

The chemical constituents were isolated and purified by macroporous adsorptive resin D101, silica gel, and ODS column chromatography and preparative HPLC. Their structures were elucidated on the basis of 1D and 2D NMR analyses. In addition, their cytotoxic activity against human hepatoma carcinoma cells (HepG-2) were evaluated by the MTT method. Furthermore, RP-HPLC and colorimetric methods were used for the analysis of cosmosiin and total flavonoids.

RESULTS

A new lignan, together with five known compounds were obtained, and their structures were characterized as (+)-pinoresinol-4'-O-β-D-glucopyranosyl-4″-O-β-D-apiofuranoside (1), cosmosiin (2), luteolin-7-O-β-D-glucopyranoside (3), liriodendrin (4), 3, 5, 4'-trihydroxy-bibenzyl-3-O-β-D-glucoside (5), and apigenin-6-C-β-D-glucopyranside (6). Furthermore, RP-HPLC and colorimetric methods were established for the analysis of cosmosiin and total flavonoids.

CONCLUSION

Compound 1 was a new lignan, and compounds 5 and 6 were isolated for the first time from the title plant. Compounds 1, 4 and 6 showed definite activities against HepG-2, while the other compounds didn't show inhibitory effects. The optimal harvest time of B. papyrifera (L.) Vent. is September.

Broussoflavonol B restricts growth of ER-negative breast cancer stem-like cells

Accumulating experimental and clinical evidence has indicated that tumor-initiating or cancer stem-like cells are a sub-population of tumor cells capable of initiating and driving tumor growth, and cancer stem-like cells are resistant to most current cancer therapies, including chemo- and radiation therapy. More effective targeted-therapeutic approaches are urgently needed to eliminate cancer stem-like cells. Here, we report that broussoflavonol B, a chemical purified from the bark of the Paper Mulberry tree (broussonetia papyrifera), exhibited potent growth inhibitory activity towards estrogen receptor (ER)-negative breast cancer SK-BR-3 cells at sub-micromolar concentrations. Broussoflavonol B more potently inhibited growth and induced differentiation of stem-like SK-BR-3 cells-compared to the anti-estrogen tamoxifen. In addition, broussoflavonol B treatment also reduced the steady, state levels of the Human epidermal growth factor receptor-2 (HER2) and ER-α36, a variant of ER-α. Our results, thus, indicate that broussoflavonol B is a potent growth inhibitor of ER-negative breast cancer stem-like cells and provide a rationale for pre-clinical and clinical evaluation of broussoflavonol B for breast cancer therapy.

Chemical composition and antioxidant activities of Broussonetia papyrifera fruits

Fruits of Broussonetia papyrifera from South China were analyzed for their total chemical composition, and antioxidant activities in ethanol and aqueous extracts. In the fruit of this plant, the crude protein, crude fat and carbohydrates was 7.08%, 3.72% and 64.73% of dry weight, respectively. The crude protein, crude fat and carbohydrates were 15.71%, 20.51% and 36.09% of dry weight, respectively. Fatty acid and amino acid composition of the fruit were analyzed. Unsaturated fatty acid concentration was 70.6% of the total fatty acids. The percentage of the essential amino acids (EAAs) was 40.60% of the total amino acids. Furthermore, B. papyrifera fruit are rich in many mineral elements and vitamins. Total phenolic content was assessed using the Folin-Ciocalteau assay, whereas antioxidant activities were assessed by measuring the ability of the two extracts to scavenge DPPH radicals, inhibit peroxidation, and chelate ferric ions. Their reducing power was also assessed. Results indicated that the aqueous extract of B. papyrifera was a more potent reducing agent and radical-scavenger than the ethanol extract. GC-MS analysis of the ethanol extract showed the presence of some acid-containing compounds. The changes in total phenolic content and antioxidant capacity in B. papyrifera from four different regions grown under normal conditions were assessed. The antioxidant activity of different extracts was positively associated with their total phenolic content. These results suggest that the fruit of B. papyrifera could be used in dietary supplement preparations, or as a food additive, for nutritional gain, or to prevent oxidation in food products.

Antioxidant phenolics from Broussonetia papyrifera fruits

Fractionation of the EtOH extract from the fruits of Broussonetia papyrifera led to the isolation of 15 phenolic compounds (1-15). Their structures were identified using spectroscopic methods. Among these compounds, 1 and 2 are new and 3-15 were isolated from this plant for the first time. Antioxidant activities of compounds 2-15 against H(2)O(2)-induced injury in SY5Y cells and 1,1-diphenyl-2-picrylhydrazyl radical scavenging activities were evaluated.

Polyphenols from Broussonetia papyrifera displaying potent alpha-glucosidase inhibition

The organic extract of the roots of Broussonetia papyrifera showed extremely high alpha-glucosidase inhibitory activity with an IC50 of around 10 microg/mL. Due to its potency, subsequent bioactivity-guided fractionation of the chloroform extract led to 12 polyphenols, 1-12, 4 of which were identified as chalcones (1-4), another 4 as flavans (5-8), 2 as flavonols (9 and 10), and 2 others as the novel species benzofluorenones (11 and 12). Broussofluorenone A (11) and broussofluorenone B (12) emerged as new compounds possessing the very rare 5,11-dioxabenzo[b]fluoren-10-one skeleton. These compounds (1-12) were evaluated for alpha-glucosidase inhibitory activity to identify their inhibitory potencies and kinetic behavior. The most potent inhibitor, 10 (IC50=2.1 microM, Ki=2.3 microM), has an inhibitory activity slightly higher than that of the potent alpha-glucosidase inhibitor deoxynojirimycin (IC50=3.5 microM). The novel alpha-glucosidase inhibitors 11 (IC50=27.6 microM) and 12 (IC50=33.3 microM) are similar in activity to sugar-derived alpha-glucosidase inhibitors such as voglibose (IC50=23.4 microM). Interestingly, major constituents (1, 2, 6, 7, 9, and 10) of B. papyrifera displayed significant inhibitory activity with IC50 values of 5.3, 11.1, 12.0, 26.3, 3.6, and 2.1 microM, respectively. In kinetic studies, chalcones (1-4) exhibited noncompetitive inhibition characteristics, whereas the others (5-12) showed mixed behavior.

[Studies on chemical constituents of fructus broussonetiae]

OBJECTIVE

To study the chemical constituents of Fructus Broussonetiae.

METHODS

Column chromatography with silic gel was employed to isolate and purify the 80% alcohol extract of Fructus Broussonetia, and the constituents were identified by spectral methods.

RESULTS

Six compounds were isolated from 80% ethanol extract. Their structures were identified as Isoterihanine (1), Chelerythrine (2), Trillin (3), Sucrose (4), beta-sitosterol (5) and Fucosterol (6).

CONCLUSION

These compounds are isolated from Fructus Broussonetiae for the first time.

Antioxidant Lignans from the Fruits of Broussonetia papyrifera

Nine new lignans, chushizisins A-I (1-9), and three known lignans, threo-1-(4-hydroxy-3-methoxyphenyl)-2-{4-[(E)-3-hydroxy-1-propenyl]-2-methoxyphenoxy}-1,3-propanediol (10), erythro-1-(4-hydroxy-3-methoxyphenyl)-2-{4-[(E)-3-hydroxy-1-propenyl]-2-methoxyphenoxy}-1,3-propanediol (11), and 3-[2-(4- hydroxyphenyl)-3-hydroxymethyl-2,3-dihydro-1-benzofuran-5-yl]propan-1-ol (12), were isolated from the fruits of Broussonetia papyrifera. Their structures were elucidated using spectroscopic methods. Compounds 1, 5, 6, 8, 9, and 11 exhibited antioxidant activities against H(2)O(2)-induced impairment in PC12 cells, while compounds 1, 2, 4, 7, and 11 showed DPPH radical-scavenging activities with IC(50) values of 236.8, 156.3, 273.9, 281.1, and 60.9 microM, respectively.

Antityrosinase and antioxidant effects of ent-kaurane diterpenes from leaves of Broussonetia papyrifera

Three new ent-kaurane type diterpenes, broussonetones A-C (1-3), were isolated from leaves of Broussonetia papyrifera, together with seven known compounds, and their structures determined by 1D and 2D NMR and MS methods. Compounds 1-3 were marginal inhibitors of tyrosinase. Antioxidant assays showed them also to be inhibitors of xanthine oxidase. The mild inhibition of tyrosinase and significant inhibition of xanthine oxidase suggests that 1-3 could be useful ingredients in the development of skin-protecting cosmetics.

Chemical constituents from the leaves of Broussonetia papyrifera

To separate and identify the chemical constituents from the leaves of Broussonetia papyrifera (Linn.) Vent, various columns including Diaion HP-20, Toyopearl HW-40C, Sephadex LH-20, silica gel were employed for the isolation and purification of compounds from the leaves of B. papyrifera. The structures of the compounds were elucidated by their physiochemical characteristics and spectral data. Nineteen compounds were isolated from the leaves of B. papyrifera and their structures were identified as apigenin (1), apigenin-7-O-beta-D-glucopyranoside (2), chrysoerid-7-O-beta-D-glucopyranoside (3), apigenin-7-O-beta-D-glucopyranuronide (4), vitexin-7-O-beta-D-glucopyranoside (5), luteolin (6), 5,7,4'-trihydroxyl-6-C-[a-L-rhamnopyranosyl (1-->2)]-beta-D-glucopyranosyl flavone (7), 5,7,4'-trihydroxyl-8-C-[a-L-rhamnopyranosyl (1-->2)]-beta-D-glucopyranosyl flavone (8), saponaretin (9), vitexin (10), benzyl benzoate-2, 6-di-O-beta-D-glucopyranoside (11), (2R, 3R, 5R, 6S, 9R)-3-hydroxy-5,6-epoxy-beta-ionol-2-O-beta-D-glucopyranoside (12), (2R, 3R, 5R, 6S, 9R)-3-hydroxyl-5,6-epoxy-acetyl-beta-ionol-2-O-beta-D-glucopyranoside (13), ficustriol (14), (6S, 9S)-roseoside (15), 3beta-hydroxy-5alpha,6alpha-epoxy-beta-ionone-2alpha-O-beta-D-glucopyranoside (16), icariside B1 (17), sammangaoside A (18), 3-hydroxy-5alpha,6alpha-epoxy-beta-ionone (19). Compounds 11, 12 and 13 are new compounds, the others are isolated from this genus Broussonetia for the first time.

[Cytoxic activities of total alkaloids isolated from fructus broussonetiae in vitro]

OBJECTIVE

To observe the cytoxic activities of total alkaloids isolated from Fructus Broussonetiae on the growth inhibition in five carcinoma cell lines.

METHODS

The growth inhibition was analyzed by MTT, Cell colony in the Hela, BEL-7402, A375, SMM1990, Saos-2 cell lines.

RESULTS

The growth of all tumor cells were inhibited by total alkaloids isolated from Fructus Broussonetiae.

CONCLUSION

The results show that total alkaloids isolated from Fructus Broussonetiae possess the role of antitumors in cell culture.

[Chemical constituents from branch of Broussonetia papyrifera]

OBJECTIVE

To investigate the chemical constituents from the branch of Broussonetia papyrifera.

METHOD

Column chromatographic methods were used to isolate the chemical constituents. ESI-MS and NMR methods were employed for their structural elucidation.

RESULT

Six compounds were isolated and identified as (2S)-7, 3'-dihydroxy-4'-methoxyflavan (1), ergosterol peroxide (2), D-galacitol (3), sulfuretin (4), liriodendrin (5), graveolone (6), respectively.

CONCLUSION

Compounds 1-6 were isolated from the plant for the first time.

[Protective effects of total flavonoids of Broussonetia papyrifera on oxidative injury of ultraviolet A to human keratinocytes]

OBJECTIVE

To investigate the oxidative damage of ultraviolet A (UVA) to human immortalized keratinocytes line HaCaT and the protective effects of total flavonoids of Broussonetia papyrifera (TFBP) gotten from the leaves of broussonetia papyifera.

METHODS

Based on the culture of the human keratinocytes, the experiment group added with different dosages of TFBP before exposure to the radiation, received the UVA radiation together with the treatment group. The levels of malondialdehyde (MDA) and the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) were determined in cultured HaCaT cells as well as the cell activity with MTT reduction assay. Human immortalized keratinocytes HaCaT cells received ultraviolet A with the different dosages between 0.46 and 2.76 J/cm(2) respectively. The protective effects of TFBP at different concentrations were also evaluated.

RESULTS

The cell activity decreased gradually from 96.3% to 37.5% with the increase of UVA dosage from 0.46 J/cm(2) to 2.76 J/cm(2). After 10 mg/L up to 200 mg/L of TFBP were added the cell activity increased, the levels of MDA decreased from (5.14 +/- 0.58) nmol/mg pro to (2.98 +/- 0.14) nmol/mg pro, the levels of SOD increased from (23.09 +/- 3.91) U/mg pro to (34.50 +/- 1.59) U/mg pro and the activity of GSH-Px increased somewhat.

CONCLUSION

Ultraviolet A causes significant oxidative injury to HaCaT cells under the conditions of this study. TFBP gotten from the leaves of broussonetia papyrifera has certain protective effect on HaCaT epithelial cells.

Antimicrobial and cytotoxic activity of 18 prenylated flavonoids isolated from medicinal plants: Morus alba L., Morus mongolica Schneider, Broussnetia papyrifera (L.) Vent, Sophora flavescens Ait and Echinosophora koreensis Nakai

Antimicrobial activity of the 18 prenylated flavonoids, which were purified from five different medicinal plants, was evaluated by determination of MIC using the broth microdilution methods against four bacterial and two fungal microorganisms (Candida albicans, Saccaromyces cerevisiae, Escherichia coli, Salmonella typhimurium, Staphylococcus epidermis and S. aureus). Papyriflavonol A, kuraridin, sophoraflavanone D and sophoraisoflavanone A exhibited a good antifungal activity with strong antibacterial activity. Kuwanon C, mulberrofuran G, albanol B, kenusanone A and sophoraflavanone G showed strong antibacterial activity with 5-30 microg/ml of MICs. Morusin, sanggenon B and D, kazinol B, kurarinone, kenusanone C and isosophoranone were effective to only gram positive bacteria, and broussochalcone A was effective to C. albicans. IC50 values of papyriflavonol A, kuraridin, sophoraflavanone D, sophoraisoflavanone A and broussochalcone A in HepG2 cells were 20.9, 37.8, 39.1, 22.1, and 22.0 microg/ml, respectively. These results support the use of prenylated flavonoids in Asian traditional medicine to treat microbial infection and indicate a high potential for prenylated flavonoids as antimicrobial agents as well as anti-inflammatory agents.

[Identification of fructus broussonetiae from different habitats and its confused species with clustering analysis by near-infrared diffuse reflectance spectrometry]

OBJECTIVE

To provide a new method for identifying Fructus Broussonetiae and its confused species.

METHODS

Cluster analysis was adopted for the identification.

RESULTS

The method can identify Fructus Broussonetiae and the results are coincident with traditional phytotaxnomy.

CONCLUSION

This method can be used for the rapid and accurate differentiation of Fructus Broussonetiae.