Peony pollen derived nitrogen-doped activated carbon for supercapacitor application

Peony pollen is a cheap and readily available biomass material with a relatively high protein content.In this work,it was employed as an N-rich precursor to prepare the nitrogen-doped porous carbon for supercapacitor application.The porous carbon microspheres were prepared through a hydrothermal method and subsequent carbonization process.Notably,ammonium borofruoride and potassium hydroxide were employed respectively as an etchant and an activator to modify the porosity of the materials.The as prepared ANPPCs-700 has a super high BET specific surface area of 824.69 m~2/g.The microstructure,chemical state and electrochemical properties of the product were investigated in detail.The prepared nitrogen-doped carbon microspheres exhibits excellent specific capacity of 209 F/g at a current density of lA/g and remained 92.5% of the initial capacitance after 5000 deep cycles at 5 A/g.     

Determination of tryptophan in bee pollen and royal jelly by high‐performance liquid chromatography with fluorescence detection

A method for tryptophan analysis in bee pollen and royal jelly was developed using HPLC with fluorescence detection. To determine the free tryptophan in bee pollen and royal jelly, ultrasonic extraction was performed using water (pH 6.3)–acetonitrile (10:1, v/v) as extraction solvent. While determining the total tryptophan in these bee products, the method involves alkaline hydrolysis of the proteins with 4 mol/L sodium hydroxide at 110°C for 20 h under anaerobic conditions. The operating conditions for the HPLC analysis were: Symmetry C₁₈ column (4.6 × 250 mm, 5 µm), 0.1% trifluoroacetic acid–methanol (75:25, v/v) as the mobile phase at a flow rate of 1.0 mL/min at 30°C. The fluorescence detector was operated at an excitation wavelength of 280 nm and an emission wavelength of 340 nm. A linear response (r² > 0.9998) was obtained in the range 0.0625–5.0 µg/mL. The method was successfully applied to the determination of the free and total tryptophan contents in bee pollens, which were 0.069 ± 0.003 and 2.693 ± 0.476 mg/g, respectively, while only the total tryptophan was detected in royal jelly, with a content of 1.743 ± 0.066 mg/g. Copyright © 2009 John Wiley & Sons, Ltd.     

微波消解-ICP-MS测定青海油菜蜂花粉中微量元素

微波消解-ICP-MS测定青海油菜蜂花粉及生物酶解破壁油菜蜂花粉的微量金属元素含量,结果表明,花粉经酶解破壁后,固体颗粒中的Al,Mn,Ni,Cu,Zn,Sr,Mo,Sb,Ba,La等微量元素的含量均有所下降,有害元素Pb、As、Hg、Cd的含量很低,均低于检出限。     

Effect of Bee Pollen on the Mechanical and Thermal Properties of Starch Films

The use of casein, starch and bee pollen as biodegradable materials has been promise. The objective of this work was the development and characterization of films containing casein, pollen and starch. The films were obtained by casting process and the solvent evaporation was performed at 40 °C/24 h. The films characterization was carried out by microscopy, thermal analysis, opacity test, mechanical properties and barrier methods. The starch films presented heterogeneous on microscopy analysis. The thermal behaviors of pollen films were similar. The formulation containing only pollen 3% was unable to form film. The introduction of pollen in starch film formulation improved the mechanical characteristic and thermal stability of films.     

In vitro cytotoxicity effects of date palm (Phoenix dactylifera L.) pollen on neonate mouse spermatogonial stem cells

There is a fast growing tendency in the use of herbal remedies in developing countries. One of the traditional medicines used for male infertility treatment is date palm (Phoenix dactylifera) pollen (DPP). Isolated spermatogonial stem cells and sertoli cells using enzymatic digestion were grown in Dulbecco's modified Eagle's medium supplemented with 4% foetal bovine serum in the absence or presence of 0.06, 0.25 and 0.62 mg/mL concentrations of aqueous extract of DPP for 2 weeks. The assessment of mean number of the whole cells and the living cells showed that there were no significant differences between the mean viability percentage and proliferation rate between control and experimental groups (P>0.05). As there are no cytotoxicity effects of DPP in our cultural system, this system can be utilised for the enrichment or differentiation of these cells in clinical applications, cell replacement therapy, tissue regeneration and tissue engineering applications.     

Miniaturized Salting-Out Assisted Liquid-Liquid Extraction Combined with Disposable Pipette Extraction for Fast Sample Preparation of Neonicotinoid Pesticides in Bee Pollen

As the main source of nutrients for the important pollinator honeybee, bee pollen is crucial for the health of the honeybee and the agro-ecosystem. In the present study, a new sample preparation procedure has been developed for the determination of neonicotinoid pesticides in bee pollen. The neonicotinoid pesticides were extracted using miniaturized salting-out assisted liquid-liquid extraction (mini-SALLE), followed by disposable pipette extraction (DPX) for the clean-up of analytes. Effects of DPX parameters on the clean-up performance were systematically investigated, including sorbent types (PSA, C18, and silica gel), mass of sorbent, loading modes, and elution conditions. In addition, the clean-up effect of classical dispersive solid-phase extraction (d-SPE) was compared with that of the DPX method. Results indicated that PSA-based DPX showed excellent clean-up ability for the high performance liquid chromatography (HPLC) analysis of neonicotinoid pesticides in bee pollen. The proposed DPX method was fully validated and demonstrated to provide the advantage of simple and rapid clean-up with low consumption of solvent. This is the first report of DPX method applied in bee pollen matrix, and would be valuable for the development of a fast sample preparation method for this challenging and important matrix.     

Automated liner exchange— A novel approach in direct thermal desorption— gas chromatography

Summary A system was developed for fully automated liner exchange in direct thermal desorption— gas chromatography— mass spectrometry (DTD-GC-MS). Samples are put into a newly developed liner which is capped with a standard crimp cap. The liners are placed in a sample tray and transported to the thermal desorption device. Both liner transport and liner exchange (which can be performed after each analysis) are automated. The system was tested for spores and pollen, vegetable oil, wood (preservative), car exhaust (BTEX), and tobacco (nicotine) analysis to demonstrate the robustness and flexibility of the approach.     

Determination of cadmium residues in bee products using a ‘lab-made’ bismuth bulk electrode

Raw propolis and bee pollen has been widely used in different areas such as medicine, food and apitherapy because they have biological and medicinal properties. The beneficial effects of both bee products for human health include antibacterial, antiviral, antimicrobial and anti-inflammatory properties. However, hives exposure to heavy metals, due beekeeping practices and environment, is one of the problems facing beekeepers. The presence of cadmium in bee products should be controlled, because of its high toxicity. A lab-made Bismuth Bulk Electrode (BiBE) was developed for cadmium residue determination in Argentinean bee products such as raw propolis and bee pollen employing square wave anodic stripping voltammetry (SWASV) as electrochemical technique. The SWASV parameters were optimised based on a 2 ⁵ factorial design. The method presents a linear range from 2.00 to 100.0 µg L^?1 of Cd (II) with a limit of detection (LOD) and a limit of quantitation (LOQ) of 0.78 µg L^?1 and 2.61 µg L^?1, respectively. The repeatability was 8.03%, calculated as the relative standard deviation. Recovery experiments were performed using spiked raw propolis and bee pollen samples with standard deviation values from 1.16% to 7.20%. The BiBE is easy and fast to elaborate and the propose method is environmentally friendly and low cost. Then, it can be considered as a good alternative to the quality control of bee products due to its importance in the beekeeping industry.     

INTRODUCING EXOGENOUS DNA INTO PLANTS AFTER POLLINATION——DNA TRAVERSE PATHWAY OF POLLEN TUBE TO REACH EMBRYONIC SAC

The technique of introducing exogenous DNA into plants through the pathway of pollen tube after pollination has been applied since 1978 for transformation of the egg, zygote or carly embryonic cells. By introducing the erogenous DNA containing the goal gene(s) into cotton and rice, several new varieties with economic value and genetic stability are obtained. Thus molecular breeding of crops can be realized by this biotechnique.The pollen tube pathway is demonstrated by tritium-labelled cotton DNA (> 50kb). The labelled DNA is injected into cotton ovaries from the center of the top 24 h after selfing. 30 min to 8 h later, the ovaries are removed. It is clearly shown that the exogenous DNA can only pass from the micrnphyle to the opened nucellus, and then reach the embryonic sac. ~3H-DNA can be found in the embryonic sacs 30 min after injection. In more than 80％ of the embryonic sacs ~3H-DNA can be seen between 2 and 4 h after injection. No ~3H-DNA is found inside the pollen tubes. Therefore it is not th