First report of an antifungal amidase from Peltophorum pterocarpum. [corrected]

Ginkgo Seed Proteins: Characteristics, Functional Properties and Bioactivities

Ginkgo biloba L. is an ancient plant relic, which is known as a "living fossil", and is widely cultivated in China. This plant with medical potential and health benefits has drawn the attention of researchers. Ginkgo seeds are rich in protein. Ginkgo seed proteins (GSPs) have good functional properties over many other seed proteins, which have the potential to be utilized as food ingredients. Moreover, GSP contains no restricted amino acids and is easy to be separated. Several GSP isolate with various bioactivities, such as antimicrobial and antioxidative activities, have been purified and evaluated for their bioactive potential. In this review, the separation methods and bioactivities of GSP were summarized, physicochemical characteristics and functional properties were comprehensively reviewed and compared with other seed proteins. Some food applications of GSP were also briefly introduced. Besides, some suggestions and prospects were discussed in this review.

In Vitro Antifungal Activity of Peltophorum dubium (Spreng.) Taub. extracts against Aspergillus flavus

Aspergillus flavus is a filamentous, saprophytic fungus, whose colonization occurs mainly in cereal grains and oilseeds once harvested. Under certain conditions, it could produce mycotoxins called aflatoxins, known as powerful human liver carcinogens. The aim of the present study was to describe the antifungal activity of extracts of Peltophorum dubium, a species from northern Argentina (Oriental Chaco), against A. flavus. The antifungal activities of different collection sites are reported. The extracts exhibited a minimum inhibitory concentration of 125 µg/mL, and the differences between the treatments and the inoculum control were 11 mm of P. dubium A and 10 mm of P. dubium F in colony growth. Moreover, hyphae treated with the extracts stained blue with Evans blue showed alterations in the membrane and/or cell wall, allowing the dye income. Bio-guided fractionation, High Performance Liquid Chromatography diode array ultraviolet/visible (HPLC UV/VIS DAD), and Ultra-High Performance Liquid Chromatography Electrospray Ionization Mass Spectrometry (UPLC ESI-MS) analyses were conducted to characterize the extracts and their active fractions. The HPLC UV/VIS DAD analysis allowed the determination of the presence of flavonoids (flavonols and flavones), coumarins, terpenes, and steroids. UPLC ESI/MS analysis of active fractions revealed the presence of Kaempferol, Apigenin, Naringenin, Chrysin and Daidzein.

Purification of an Antifungal Peptide from Seeds of Brassica oleracea var. gongylodes and Investigation of Its Antifungal Activity and Mechanism of Action

In this study, a 8.5-kDa antifungal peptide designated as BGAP was purified from the crude extract of the seeds of Brassica oleracea var. gongylodes by employing a protocol that comprised cation exchange chromatography on SP-Sepharose, cation exchange chromatography on Mono S and gel filtration chromatography on Superdex peptide. BGAP showed the highest amino acid sequence similarity to defensin peptides by mass spectrometric analysis. BGAP showed a broad spectrum of antifungal activity with a half maximal inhibitory concentration at 17.33 μg/mL, 12.37 μg/mL, 16.81 μg/mL, and 5.60 μg/mL toward Colletotrichum higginsianum, Exserohilum turcicum, Magnaporthe oryzae and Mycosphaerella arachidicola, respectively. The antifungal activity of BGAP remained stable (i) after heat treatment at 40–100 °C for 15 min; (ii) after exposure to solutions of pH 1–3 and 11–13 for 15 min; (iii) after incubation with solutions containing K⁺, Ca²⁺, Mg²⁺, Mn²⁺ or Fe³⁺ ions at the concentrations of 20–150 mmol/L for 2 h; and (iv) following treatment with 10% methyl alcohol, 10% ethanol, 10% isopropanol or 10% chloroform for 2 h. Fluorescence staining experiments showed that BGAP brought about an increase in cell membrane permeability, a rise in reactive oxygen species production, a decrease in mitochondrial membrane potential, and an accumulation of chitin at the hyphal tips of Mycosphaerella arachidicola.

Chemical Constituents of the Leaves of Peltophorum pterocarpum and Their Bioactivity

Two new sesquiterpenoids peltopterins A and B (compounds 1 and 2) and fifty-two known compounds were isolated from the methanol extract of P. pterocarpum and their chemical structures were established through spectroscopic and mass spectrometric analyses. The isolates 40, 43, 44, 47, 48, 51 and 52 exhibited potential inhibitory effects of superoxide anion generation or elastase release.

Plant antifungal proteins and their applications in agriculture

Fungi are far more complex organisms than viruses or bacteria and can develop numerous diseases in plants that cause loss of a substantial portion of the crop every year. Plants have developed various mechanisms to defend themselves against these fungi which include the production of low-molecular-weight secondary metabolites and proteins and peptides with antifungal activity. In this review, families of plant antifungal proteins (AFPs) including defensins, lectins, and several others will be summarized. Moreover, the application of AFPs in agriculture will also be analyzed.

Purification and characterization of a novel antimicrobial peptide from sheep reproductive tract

A novel antimicrobial peptide, SRTAP-40 has been purified and characterized from sheep reproductive tract. The isolation procedure entailed acetic acid extraction, gel filtration chromatography, and HPLC. SRTAP-40 is composed of 40 amino acid residues with a MW of 4,820.47 Da from MALDI-TOF-MS. Its N-terminal sequence was AYVLDEPKP. SRTAP-40 cDNA was cloned by 3'-RACE. SRTAP-40 showed activity against E. coli Staphylococcus aureus, Streptococcus sp. and, Candida albicans with MIC values of 12, 12, 24, 6 μg/ml, respectively. By BLAST search, SRTAP-40 had no significant similarity to any known peptide.

Phytochemical constituents and antibacterial efficacy of the flowers of Peltophorum pterocarpum (DC.) Baker ex Heyne

OBJECTIVE

To investigate the preliminary phytochemistry and antibacterial activity of the flower extract of Peltophorum pterocarpum .

METHODS

Phytochemical analysis was done by using the standard methods given by Harbone. The methanolic flower extract were tested against Escherichia coli, Klebsiella pneumonia, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus cereus, Salmonella typhi, Serratia marsecens, Acinetobacter baumannii, Enterobacter sp., Proteus mirabilis, Enterococcus faecalis and Streptococcus pyogenes by the agar disc diffusion method.

RESULTS

Preliminary phytochemical screening of flower extract showed the presence of phenolic compounds, flavonoids, saponins, steroids, tannins, xanthoproteins, carboxylic acids, coumarins and carbohydrates. The flower extract of Peltophorum pterocarpum showed significant activity against four gram positive (Staphylococcus aureus, Bacillus cereus, Enterococcus faecalis and Streptococcus pyogenes) and three gram negative bacteria (Proteus mirabilis, Acinetobacter baumannii and Serratia marsecens), out of 12 pathogenic bacteria studied.

CONCLUSIONS

The findings of the present study confirm the presence of significant antibacterial activity against human pathogens in the flowers of Peltophorum pterocarpum.

Molecular cloning and characterisation of a pathogenesis-related protein CsPR10 from Crocus sativus

Plants have developed many mechanisms to protect themselves against most potential microbial pathogens and diseases. Among these mechanisms, pathogenesis-related proteins are produced as part of the active defence to prevent attack. In this study, a full-length cDNA encoding the CsPR10 protein was identified in fresh saffron stigmas (Crocus sativus). The deduced amino acid sequence from the nucleotide sequence of the coding region showed homology with PR10 proteins. The clone expressed as a protein in fusion with a GST tag produced a 47-kDa protein in E. coli. CsPR10 had ribonuclease activity, with features common to class II-type ribonucleases; its specific activity was quantified as 68.8 U·mg(-1) protein, thus falling within the range of most PR10 proteins exhibiting RNase activity. Antifungal activity of CsPR10 was assayed against Verticillium dahliae, Penicillium sp. and Fusarium oxysporum. CsPR10 inhibited only F. oxysporum growth, and antifungal potency was reflected in a IC(50) of 8.3 μm. Expression analysis showed the presence of high transcript levels in anther and tepal tissues, low levels in stigmas and roots, and no signal detected in leaves. This protein seems to be involved in the active defence response through activation of the jasmonic acid pathway.