Biotransformation of ent-pimaradienoic acid by cell cultures of Aspergillus niger

Microbial transformation stands out among the many possible semi-synthetic strategies employed to increase the variety of chemical structures that can be applied in the search for novel bioactive compounds. In this paper we obtained ent-pimaradienoic acid (1, PA, ent-pimara-8(14),15-dien-19-oic acid) derivatives by fungal biotransformation using Aspergillus niger strains. To assess the ability of such compounds to inhibit vascular smooth muscle contraction, we also investigated their spasmolytic effect, along with another five PA derivatives previously obtained in our laboratory, on aortic rings isolated from male Wistar rats. The microbial transformation experiments were conducted at 30 °C using submerged shaken liquid culture (120 rpm) for 10 days. One known compound, 7α-hydroxy ent-pimara-8(14),15-dien-19-oic acid (2), and three new derivatives, 1β-hydroxy ent-pimara-6,8(14),15-trien-19-oic acid (3), 1α,6β,14β-trihydroxy ent-pimara-7,15-dien-19-oic acid (4), and 1α,6β,7α,11α-tetrahydroxy ent-pimara-8(14),15-dien-19-oic acid (5), were isolated and identified on the basis of spectroscopic analyses and computational studies. The compounds obtained through biotransformation (2–5) did not display a significant antispasmodic activity (values ranging from 0% to 16.8% of inhibition); however the previously obtained diterpene, methyl 7α-hydroxy ent-pimara-8(14),15-dien-19-oate (8), showed to be very effective (82.5% of inhibition). In addition, our biological results highlight the importance to study the antispasmodic potential of a large number of novel diterpenes, to conduct further structure–activity relationship investigations.     

Anti-inflammatory and anti-apoptotic effects of (RS)-glucoraphanin bioactivated with myrosinase in murine sub-acute and acute MPTP-induced Parkinson’s disease

This study was focused on the possible neuroprotective role of (R_S)-glucoraphanin, bioactivated with myrosinase enzyme (bioactive R_S-GRA), in an experimental mouse model of Parkinson’s disease (PD). R_S-GRA is one of the most important glucosinolates, a thiosaccharidic compound found in Brassicaceae, notably in Tuscan black kale seeds.R_S-GRA was extracted by one-step anion exchange chromatography, further purified by gel-filtration and analyzed by HPLC. Following, pure R_S-GRA was characterized by ¹H and ¹³C NMR spectrometry and the purity was assayed by HPLC analysis of the desulfo-derivative according to the ISO 9167-1 method. The obtained purity has been of 99%.To evaluate the possible pharmacological efficacy of bioactive R_S-GRA (administrated at the dose of 10 mg/kg, ip +5 μl/mouse myrosinase enzyme), C57BL/6 mice were used in two different sets of experiment (in order to evaluate the neuroprotective effects in different phases of the disease), according to an acute (2 injections · 40 mg/kg MPTP) and a sub-acute (5 injections · 20 mg/kg MPTP) model of PD.Behavioural test, body weight changes measures and immunohistochemical localization of the main PD markers were performed and post-hoc analysis has shown as bioactive R_S-GRA is able to reduce dopamine transporter degradation, tyrosine hydroxylase expression, IL-1β release, as well as the triggering of neuronal apoptotic death pathway (data about Bax/Bcl-2 balance and dendrite spines loss) and the generation of radicalic species by oxidative stress (results focused on nitrotyrosine, Nrf2 and GFAP immunolocalization). These effects have been correlated with the release of neurotrophic factors, such as GAP-43, NGF and BDNF, that, probably, play a supporting role in the neuroprotective action of bioactive R_S-GRA. Moreover, after PD-induction mice treated with bioactive R_S-GRA are appeared more in health than animals that did not received the treatment both for phenotypic behaviour and for general condition (movement coordination, presence of tremors, nutrition).Overall, our results suggest that bioactive R_S-GRA can protect neurons against the neurotoxicity involved in PD via an anti-apoptotic/anti-inflammatory action.     

Caratteristiche della fosfo-gluco-isomerasi di una pianta superiore

Abstract

PHOSPHOGLUCOISOMERASE FROM PEA COTYLEDONS. — 6-P-glucose iso-merase has been purified from pea cotyledons. A 70-fold purification has been obtained by means of acetone fractionation and two absorption-elution steps on calcium phosphate gel. The partially purified enzyme is free of interfering activities.

KM values of 2.5×10^?4 and 10^?4 been measured for glucose-6-P and fructose-6-P respectively. reaction, measured at pH 7.8 and 30° C., is 3.7 (Gl-6-PIFr-6-P).

The enzyme is not inhibited by p-chloro-mercurybenzoate up to 10^?3 M. Besides the substances already known to inhibit competitively the isomerase from animal tissues, the pea enzyme has been found to be competitively inhibited by ribose-5-P and by triosespho-sphates, the K₁, being respectively 7×10^?4 and 2.5×10^?4.

The properties of the pea enzyme are compared to those of animal tissues isomerase. The possible physiological significance of these properties is discussed.     

AZione Della Luce Sull'Assorbimento Salino Da Parte Di Tessuti Clorofilliani In Ambiente Privo Di CO2

Abstract

Effect of light on uptake by photosynthetic tissues in the absence of co₂. — The effect of light and of CO₂ on the uptake of ⁸⁶Rb and ^-32P by isolated leaves of Elodea canadensis has been studied. The uptake of both these ions is strongly stimulated by light both in the presence and in the absence of CO₂. In the case of phosphate, light stimulates uptake and inhibits the leakage of the ion from the tissues.

These results which confirm and extend the results of other Authors, support the conclusion that the stimulation by light of active uptake of solutes by green tissues is physiologically relevant. Furthermore, they suggest that the utilization of light energy for active uptake does not depend on CO₂ fixation and assimilation.     

A Tenebrionid beetle’s dataset (Coleoptera,Tenebrionidae) from Peninsula Valdés (Chubut,?Argentina)

The Natural Protected Area Peninsula Valdés, located in Northeastern Patagonia, is one of the largest conservation units of arid lands in Argentina. Although this area has been in the UNESCO World Heritage List since 1999, it has been continually exposed to sheep grazing and cattle farming for more than a century which have had a negative impact on the local environment. Our aim is to describe the first dataset of tenebrionid beetle species living in Peninsula Valdés and their relationship to sheep grazing. The dataset contains 118 records on 11 species and 198 adult individuals collected. Beetles were collected using pitfall traps in the two major environmental units of Peninsula Valdés, taking into account grazing intensities over a three year time frame from 2005–2007. The Data quality was enhanced following the best practices suggested in the literature during the digitalization and geo-referencing processes. Moreover, identification of specimens and current accurate spelling of scientific names were reviewed. Finally, post-validation processes using DarwinTest software were applied. Specimens have been deposited at Entomological Collection of the Centro Nacional Patagónico (CENPAT-CONICET). The dataset is part of the database of this collection and has been published on the internet through GBIF Integrated Publishing Toolkit (IPT) (http://data.gbif.org/datasets/resource/14669/). Furthermore, it is the first dataset for tenebrionid beetles of arid Patagonia available in GBIF database, and it is the first one based on a previously designed and standardized sampling to assess the interaction between these beetles and grazing in the area. The main purposes of this dataset are to ensure accessibility to data associated with Tenebrionidae specimens from Peninsula Valdés (Chubut, Argentina), also to contribute to GBIF with primary data about Patagonian tenebrionids and finally, to promote the Entomological Collection of Centro Nacional Patagónico (CENPAT-CONICET) and its associated biodiversity data. For these reasons, we believe that this information will certainly be useful for future faunistic, ecological, conservational and biogeographical studies.