Catalytic degradation of methylene blue using silver nanoparticles synthesized by honey

This investigation displayed the good catalytic activity of silver nanoparticles (AgNPs) on the reduction of methylene blue dye. During this work, Honey was chosen for environmentally reducing and stabilizing agents for preparation of silver nanoparticles then characterized these nanoparticles by ultraviolet–visible spectroscopy (UV–Vis), functional biomolecules were confirmed by Fourier transform infrared spectroscopy (FTIR). Via transmission electron microscopy (TEM), the size and shape of silver nanoparticles revealed that the particles are spherical and monodispersed without major agglomeration, the particle size ranging from 5 to 25 nm, in addition, the largest particle density levels are 5–10 nm, ZETA Seizers studied the size distribution of the colloidal solution. UV/Vis spectrophotometer and HPLC were used to study and analyze the degradation performance of silver nanoparticles on methylene blue. The results show that 92% of methylene blue has been degraded after 72 h. additionally, several new peaks have appeared after treatment of the samples by using HPLC.     

Food Reward Chemistry Explains a Novel Pollinator Shift and Vestigialization of Long Floral Spurs in an Orchid

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New species and unexpected diversity of socially parasitic bees in the genus Inquilina Michener (Hymenoptera: Apoidea: Apidae)

Abstract  Allodapine bees present particular problems for taxonomy due to a high level of morphological conservatism in adults, even between genera. However, this tribe of bees also presents a unique opportunity to explore the evolution of social parasitism because of the comparatively large number of origins of socially parasitic species. Morphological differences presented here, along with DNA sequence data and molecular phylogenetic analyses, indicate a much larger number of Australian social parasite species in the genus Inquilina than previously anticipated, and suggest that the final number of socially parasitic species may be considerable. We describe five new species and present sequence data that will help elucidate the delineation of further new species. Inquilina provides a unique opportunity to study the evolution of social parasitism in social insects, but further studies will need to encompass both population genetic and phylogenetic approaches.     

Phylogeny of a paradigm lineage: the Drosophila melanogaster species group (Diptera: Drosophilidae)

Although Drosophila melanogaster is a paradigm eukaryote for biology, relationships of this species and the other 174 species in the melanogaster species group are poorly explored and ambiguous. Gene regions of Cytochrome oxidase II (mt:CoII ), Alcohol dehydrogenase ( Adh ) and hunchback ( hb ) were sequenced and analysed phylogenetically to test prior hypotheses of relationships for the group based on chromosomes, morphology, and 28S rRNA gene sequences. A simultaneous cladistic analysis of the three newly sequenced gene regions produced a single well-resolved phylogeny for 49 exemplar species representing eight subgroups. Monophyly of each of the ananassae , melanogaster , montium , and takahashii subgroups is supported; the suzukii subgroup is polyphyletic. This phylogeny is consistent with variation in significant morphological structures, such as the male sex comb on the fore tarsus. The broad range of morphological variation among these species is interpreted and the applicability to evolution and developmental investigations is discussed. This phylogeny facilitates comparative investigations, such as gene family evolution, transposable element transmission, and evolution of morphological structures. © 2002 The Linnean Society of London, Biological Journal of the Linnean Society , 2002, 76 , 21–37.     

Comparative study of physio-chemical analysis of fresh and branded honeys from Pakistan

Honey is a nutritious substance produced by bees. Its quality and nutritional value is of great importance for consumers. Keeping this in view physicochemical and minerals determination as quality parameters of fresh floral Pakistani honeys produced by A. mellifera and branded honeys was conducted. The results of fresh honey indicated average means of Color as 48.78 mmPfund, pH 4.9, Total acidity 37.14 meq/kg, Moisture content 18.62%, Electrical conductivity 0.23 mS/cm, Ash content 0.49%, HMF content 30.85 mg/kg, Proline 365.84 mg/kg, Diastase activity 34.39(DN) and Invertase activity was 68.61(IN) comparable to honey standards. Natural honey were rich in k+ (408.46 ppm) and Na+ (405 ppm). Although Ca+ was very low. Whereas, Co, Mn and Ba concentrations exceed the 1 ppm. However, Pb, Cr, and Mo were unnoticeable. Similarly, Color, pH, MC, EC, T. Acidity, HMF, Proline, Ash content, Diastase and Invertase activity of branded honey samples average means found were 42.5 mmPfund, 5.05, 20.5%, 0.18 mS/cm, 15.34 meq/kg, 36.5 mg/kg, 181.6 mg/kg, 1.11%, 7.90(DN) and 36.97(IN) respectively. The findings showed that fresh honey samples were good and of consumable quality as per honey standards than branded honey. Higher HMF content and lower enzymatic activity in branded honey sample than the Codex standards revealed its either long or improper storage.     

The fungicide Pristine® inhibits mitochondrial function in vitro but not flight metabolic rates in honey bees

Honey bees and other pollinators are exposed to fungicides that act by inhibiting fungal mitochondria. Here we test whether a common fungicide (Pristine®) inhibits the function of mitochondria of honeybees, and whether consumption of ecologically-realistic concentrations can cause negative effects on the mitochondria of flight muscles, or the capability for flight, as judged by CO₂ emission rates and thorax temperatures during flight. Direct exposure of mitochondria to Pristine® levels above 5 ppm strongly inhibited mitochondrial oxidation rates in vitro. However, bees that consumed pollen containing Pristine® at ecologically-realistic concentrations (≈1 ppm) had normal flight CO₂ emission rates and thorax temperatures. Mitochondria isolated from the flight muscles of the Pristine®-consuming bees had higher state 3 oxygen consumption rates than control bees, suggesting that possibly Pristine®-consumption caused compensatory changes in mitochondria. It is likely that the lack of a strong functional effect of Pristine®-consumption on flight performance and the in vitro function of flight muscle mitochondria results from maintenance of Pristine® levels in the flight muscles at much lower levels than occur in the food, probably due to metabolism and detoxification. As Pristine® has been shown to negatively affect feeding rates and protein digestion of honey bees, it is plausible that Pristine® consumption negatively affects gut wall function (where mitochondria may be exposed to higher concentrations of Pristine®).     

How does a colony of Apoica flavissima (Hymenoptera: Vespidae,Epiponini) maintain a constant temperature?

The thermal characteristics of a colony of Apoica flavissima , an epiponine wasp, were examined. The nest, with a diameter of slightly less than 30 cm, was built on a twig of an orange tree. The temperature of the roof surface fluctuated greatly, ranging between 19.1 and 41.5°C. However, the temperature in the central cell was kept constant at around 27°C throughout a day. Although heavy rain pelted the nest roof in the morning, the central cell maintained temperatures higher than 25°C. On the contrary, after all immature and adult wasps were removed the temperature in the nest fluctuated considerably. The presence of immature individuals and adult wasps densely covering the under surface of the comb seemed to function as an effective insulator. The smaller temperature fluctuation in the central cell than on the roof surface, when the nest was in the empty state, suggests that the thick spongy tissue of the roof made from curled plant leaf hairs serves as an insulator to prevent the conduction of solar heat into the cells and the outward flow of heat generated in cells, especially at night.