57 research outputs found
EXPERIMENTS WITH A FAST CHOPPER SYSTEM FOR INTENSE ION BEAMS
Abstract Chopper systems are used to pulse charged particle beams. In most cases, electric deflection systems are used to generate beam pulses of defined lengths and appropriate repetition rates. At high beam intensities, the field distribution of the chopper system needs to be adapted precisely to the beam dynamics in order to avoid aberrations For the Frankfurt Neutron Source FRAN
The activity of acid glycosidases in royal jelly collected from queen bee’s cells at different stages of larvae development
Przedstawione badania dotyczą aktywności kwaśnych glikozydaz w mleczku pszczelim oraz w larwach matek na różnych etapach rozwoju. Aktywność kwaśnych glikozydaz oznaczano w mleczku pobieranym w trzecim (M I) i piątym (M II) dniu rozwoju larw oraz w odpowiadającym mu czasowo larwach (L I i L II). Największą aktywność w mleczku pszczelim wykazywały: β-glukozydaza, α-mannozydaza i β-N-acetylo-D-heksozaminidaza. W larwach matek pszczelich stwierdzono stosunkowo duże wartości aktywności α-mannozydazy, α-glukozydazy i β-N-acetylo-D-heksozaminidazy. Wartości aktywnośi enzymów w gruczołach podgardzielowych pszczół Apis mellifera wzięto z wyników badań Costy i Cruz-Landima opublikowanych w 2005 roku. W gruczołach podgardzielowych występował wysoki poziom aktywności β-glukozydazy, natomiast pozostałe z badanych enzymów występowały w ilościach śladowych. Na podstawie wyników badań własnych oraz badań Costy i Cruz-Landima opublikowanych w 2005 roku w pracy przedstawiono sugestię, że kwaśne glikozydazy w mleczku pszczelim mogą częściowo pochodzić z wydzielin larw. Rozważono również pozytywny wpływ wydzielin larw na składniki glikanowe mleczka pszczelego.Royal jelly (RJ) is a secretion of hypopharyngeal glands of young worker bees ‘nurses’. It is used to feed all the larvae in the bee colony during the first 3 days of their life, and the mother bee for the whole stage of larvae. Within the royal jelly there is a number of enzymes from the group of acid glycosidases. Their main purpose is digestion of carbohydrates and carbohydrate components of glycoconjugates. The aim of the study was an attempt to determine the origin of the activity of acid glycosidases in royal jelly. Royal jelly was collected in May and June in the breeding apiary “Wojtek” in the village of Breń Osuchowski, community Czermin close to Mielec. Royal jelly was harvested, placed in a thermos with ice, and transported to the laboratory. Than samples of approximately 1 cm³ were prepared and frozen at –78°C. After thawing, the samples were weighed, diluted with 3-fold volume of saline (0.9% NaCl) containing 0.1% Triton X-100 and homogenized. Larvae of mother bees were extracted from nurseries. Than test portion from 5 larvae were homogenized with 3-fold volume of saline containing 0.1% Triton X-100. Enzyme activity was determined in royal jelly that was collected in the third (M I) and fifth (M II) day of larval development and from larvae at the corresponding time (L I and L II). The optimal pH for the investigated acid glycosidases in royal jelly and in larvae homogenates was determined. Activity of acid glycosidases was determined using spectrometric method by Barrett and Heath from 1977. It was assumed that the unit of enzyme activity (U) is the activity of enzyme which converts 1 μmol of substrate during 1 min at 30°C. The enzyme activity was given in mU for 1 mg of royal jelly or 1 mg weight of larvae. The statistical calculations were conducted using Statistica 8.0 (Stat. Soft., Inc., Tulsa, OK., USA). The highest activity of enzymes in royal jelly was observed for β-glucosidase, α-mannosidase and β-N-acetyl-D-hexosaminidase. However, in the larvae from queen bee’s cells activity α-mannosidase, β-N-acetyl-D-hexosaminidase and α-glucosidase were relatively high. Activity of these enzymes in the hypopharyngeal glands of the honey bee Apis mellifera was given by the authors Costa and Cruz-Landim in publication from 2005. In the hypopharyngeal glands there is a high level of β-glucosidase activity, while the other of the enzymes were detected in trace amounts only. Based on our results and on the results presented by Costa and Cruz-Landim in 2005, it is suggested, that acid glucosidase in royal jelly may partly come from the secretions of the larvae. Also the positive influence of larvae secretion on glycan ingredients of royal jelly was considered
- …