A novel pyrazolone complex P-FAH-Cu-bpy induces death of Escherichia coli and Staphylococcus aureus by disrupting cell structure and blocking energy.

A novel pyrazolone-based copper complex [Cu(L)(bpy)]∙CH3OH (P-FAH-Cu-bpy) was synthesized and previously characterized to have antitumor properties. This study aimed to investigate its antibacterial properties and action modes against Escherichia coli and Staphylococcus aureus. By agar diffusion assay, P-FAH-Cu-bpy showed strong antibacterial activity against E. coli and S. aureus with the diameter of inhibition zone of 10.17-12.50 mm and 11.83-14 mm, respectively. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the complex were 1.5 and 3 µM, respectively. Destroyed bacteria cells and debris were clearly observed by SEM. At 2 MIC and 4 MIC of P-FAH-Cu-bpy, 1.1683 and 1.9083 pg copper per cell was taken by E. coli, and 4.5670 and 8.5250 pg per cell by S. aureus, respectively. Multi-step resistance selection showed both bacteria were sensitive to P-FAH-Cu-bpy without induction of resistance within 30 generations. With P-FAH-Cu-bpy treatment, the release of nucleotides and proteins and alkaline phosphatase was increased, but the activity of K+-Na+-ATPase and Ca2+-Mg2+-ATPase and membrane conductivity were decreased in both pathogens. In conclusion, P-FAH-Cu-bpy induced death of both bacteria by destroying the cell membrane structure and blocking energy and exhibited strong antibacterial activity against E. coli and S. aureus without inducing microbial resistance.

Genome sequencing and functional annotation of Bacillus sp. strain BS-Z15 isolated from cotton rhizosphere soil having antagonistic activity against Verticillium dahliae.

In the present study, antagonistic activity of bacterial strain BS-Z15, was evaluated against Verticillium dahlia. The fermented broth of BS-Z15 inhibited the growth of Verticillium dahliae. The genome of strain BS-Z15 had a total size of 4,068,702 base pairs and contained 4318 genes, of which 4196 are coding sequences and 122 are non-coding RNA. Among these genes, nine genomic islands, 86 tRNAs, 13 sRNAs, and one prophage was determined. With the help of annotation databases, most unigene functions were identified. At the same time, genomic comparison between BS-Z15 and 12 Bacillus members showed that the genes of BS-Z15 were closely related to the Bacillus group, and were conserved between the two groups, including most of the genes associated with fungal antagonism. BS-Z15 contains genes involved in a variety of antagonistic mechanisms, including genes encoding or synthesizing mycosubtilin, chitinases (but not CHIA and CHIB), glycoside hydrolases, iron nutrients, and antibiosis. However, it only contained the complete mycosubtilin- and bacilibactin-related operators in the reported main antifungal gene cluster of B. subtilis. Mycosubtilin and bacilibactin may be the main active antifungal substance. Besides, some genes could encode products related to biofilm production, which may be related to the colonization ability of the strain in plant rhizospheres. The complete genome of B. subtilis BS-Z15 provided new insights into the potential metabolites it produces related to its biocontrol activity.

Synthesis and in vitro biological evaluation of novel coumarin derivatives containing isoxazole moieties on melanin synthesis in B16 cells and inhibition on bacteria.

A novel series of coumarin derivatives 6a-o, bearing isoxazole moieties were designed and synthesized. After that, they were evaluated for melanin synthesis in murine B16 cells and inhibitory effect on the growth of CA (Candida albicans), EC (Escherichia coli), SA (Staphylococcus aureus). It was found that eleven compounds (6b-f, 6j-o) showed a better activity on melanin synthesis than positive control (8-MOP). Among them, compounds 6d (242%) and 6f (390%), with nearly 1.6 and 2.6-fold potency compared with 8-MOP (149%) respectively, were recognized as the most promising candidate hits for further pharmacological study of anti-vitiligo. Seven halogen substituted compounds exhibited moderate antimicrobial activity against CA. It is interesting that 6e-f and 6l-m, which had two halogens on the benzene showed a comparable activity with Amphotericin B against CA. The evaluation of melanin synthesis in B16 cells and inhibitory effect on bacteria of above structurally diverse derivatives had also led to an outline of structure-activity relationship.

Isochlorogenic acid A promotes melanin synthesis in B16 cell through the ß-catenin signal pathway.

Isochlorogenic acid A, also called 3,5-dicaffeoylquinic acid (3,5-diCQA), is a widespread phenolic compound in the plant. Recent studies have shown that it has antioxidant and anti-inflammatory activity. In addition, oxidative stress and inflammation induced by solar ultraviolet radiation is a very significant reason for skin depigmentation. Therefore, in this study, we evaluated the effect of 3,5-diCQA on B16 cells and explored its molecular mechanism. Results showed that 3,5-diCQA upregulated intracellular melanin production in a time- and dose-dependent manner. Tyrosinase (TYR) activity was also increased after treatment with 3,5-diCQA in a dose-dependent manner. Expressions of TYR, TYR-related protein1, TYR-related protein2, and microphthalmia-associated transcription factor were upregulated in a dose-dependent manner after 48 h of treatment with 3,5-diCQA. Results also showed that 3,5-diCQA promoted the phosphorylation of Akt at Thr308 and glycogen synthase kinase-3ß at Ser 9. Moreover, 3,5-diCQA increased the content of ß-catenin in cell cytoplasm and nucleus by reducing the content of phosphorylated ß-catenin (p-ß-catenin). All these results suggest that 3,5-diCQA may mediate the acceleration of melanin synthesis by the ß-catenin signal pathway.

The combination of Brassica rapa L. polysaccharides and cisplatin enhances the anti liver cancer effect and improves intestinal microbiota and metabolic disorders.

Polysaccharides are commonly used as low-toxicity anticancer active substances to enhance the chemotherapeutic effect of cisplatin and reduce toxicity. Brassica rapa L. polysaccharides have been shown to have hepatoprotective effects; however, their anticancer effects in combination with cisplatin and their mechanisms have not been reported. An acidic polysaccharide from Brassica rapa L. (BRCPe) using hydroalcohol precipitation-assisted sonication was Characterized. The effects of BRCPe combined with cisplatin treatment on tumor growth in hepatocellular carcinoma mouse model were investigated. The impact of the combined treatment on the composition of intestinal flora, levels of short-chain fatty acids and endogenous metabolites in tumor mice were analyzed based on macrogenomic and metabolomic data Our results showed that the BRCPe combined with low-dose Cisplatin group showed better inhibitory activity against hepatocellular carcinoma cell growth in terms of tumor volume, tumor weight, and tumor suppression rate compared with the BRCPe and Cisplation alone group, and reduced the side effects of cisplatin-induced body weight loss, immune deficiency, and liver injury. Furthermore, BRCPe combined with cisplatin was found to induce apoptosis in hepatocellular carcinoma cell through the activation of the caspase cascade reaction. In addition, the intervention of BRCPe were observed to modulate the composition, structure and functional structure of intestinal flora affected by cisplatin. Notably, Lachnospiraceae bacteria, Lactobacillus murinus, Muribaculaceae, and Clostridiales bacteria were identified as significant contributors to microbial species involved in metabolic pathways. Moreover, BRCPe effectively regulate the metabolic disorders in cisplatin-induced hepatocellular carcinoma mice. In conclusion, BRCPe could potentially function as an adjuvant or dietary supplement to augment the effectiveness of cisplatin chemotherapy through the preservation of a more efficient intestinal microenvironmental homeostasis.

Chemical components of Hyssopus seravshanicus: antioxidant activity, activations of melanogenesis and tyrosinase, and quantitative determination by UPLC-DAD.

Hyssopus seravshanicus (Dubj.) Pazij has been used as traditional herb and food due to its wide biological properties. Seventeen known compounds were isolated from the ethyl acetate fraction. Their structures were identified by spectroscopic data and comparison with published data. Among them, 14 ones were identified from H. seravshanicus for the first time. DPPH and ABTS radical scavenging activities for crude ethanol extract (CEE), ethyl acetate fraction (EAF), butanol fraction (BF) and compounds 1, 3, 8, 10, 11 and 13 were performed. CEE, compounds 1, 3, 11 and 13 exhibited potent antioxidant activities. Compound 1 was found to increase the melanin content and tyrosinase activity of B16 melanoma cells. Moreover, the quantitative estimation of compound 1 in the ethyl acetate fraction was carried out by UPLC-DAD and the method was validated. This is the first report on the isolation and bioactivity research on the non-valotile components of H. seravshanicus.

Potential anti-vitiligo properties of cynarine extracted from Vernonia anthelmintica (L.) Willd.

Vitiligo is a depigmentation disorder of the skin. It is primarily caused by the destruction of melanocytes or obstruction of the melanin synthesis pathway. Melanin is a type of skin pigment that determines skin color. The seeds of Vernonia anthelmintica (L.) Willd (Kaliziri) are used for treating skin diseases including vitiligo in traditional Uyghur medicine. 1,5­Dicaffeoylquinic acid (1,5­diCQA) is a natural polyphenolic compound widely distributed in plants and extracted from Kaliziri seeds. Therefore, in the present study, the effect of 1,5­diCQA on melanin synthesis in B16 cell was evaluated, and its molecular mechanism was explored. The results indicated that 1,5­diCQA treatment of B16 cells stimulated an increase of intracellular melanin level and tyrosinase (TYR) activity without cytotoxicity. Reverse transcription quantitative polymerase chain reaction results also indicated that 1,5­diCQA may markedly improve the protein expression and RNA transcription of microphthalmia­associated transcription factor (MITF), melanogenic enzyme Tyr, tyrosinase­related protein 1 (TRP 1) and tyrosinase­related protein 2 (TRP 2). Additional results identified that 1,5­diCQA may promote the phosphorylation of p38 mitogen­activated protein kinase (p38 MAPK) and extracellular signal­regulated kinase (ERK) MAPK. Notably, the increased levels of intracellular melanin synthesis and tyrosinase expression induced by 1,5­diCQA treatment were significantly attenuated by the protein kinase A (PKA) inhibitor H­89. Intracellular cyclic adenosine monophosphate (cAMP) concentration and phosphorylation of cAMP­response element binding protein was increased following 1,5­diCQA treatment. These results indicated that 1,5­diCQA stimulated melanogenesis via the MAPK and cAMP/PKA signaling pathways in B16 cells, which has potential therapeutic implications for vitiligo.