Albert V. Berg

Multifidin—A cyanoglucoside in the latex of Jatropha multifida

Abstract A novel non-cyanogenic cyanoglucoside, 1-cyano-3-β- d -glucopyranosyloxy-(Z)-1-methyl-1-propene, was isolated from the latex of Jatropha multifida . The compound was named multifidin.

Podacycline A and B, two cyclic peptides in the latex of Jatropha podagrica

Two novel cyclic peptides were isolated from the latex of Jatropha podagrica, which we named podacycline A and B. Podacycline A is a cyclic nonapeptide with the sequence Gly1-Leu2-Leu3-Gly4-Ala5-Val6-Trp7-Ala8-Gly9+ ++-Gly1. The sequence of podacycline B, a cyclic heptapeptide, was determined to be Phe1-Ala2-Gly3-Thr4-Ile5-Phe6-Gly7-Phe1. The amino acid residues of both compounds were found to have the L-configuration.

Synthesis and biological activity of polygalloyl-dendrimers as stable tannic acid mimics

Inspired by the structure of tannic acid, first- to third-generation dendrimers containing two, four, and eight galloyl moieties were synthesized. Stability, antioxidant activity and collagen cross-linking activity of the natural product and its dendrimer analogues were compared. The experimental results indicate that polygalloyl dendrimers might be used as new lead compounds to improve the long-term healing characteristics of burn wounds.

Coumarins from Cedrelopsis grevei (Ptaeroxylaceae).

The stem bark of Cedrelopsis grevei Baill. has yielded the first reported examples of 5-prenylated coumarins, cedrecoumarin A and B as well as the known coumarins, cedrelopsin, scoparone, O-methylcedrelopsin and norbraylin, and the known chromones ptaeroglycol and ptaeroxylinol.

Transaminase and alkaline phosphatase activity in the serum of burn patients treated with highly purified tannic acid.

The effects of local treatment with highly purified tannic acid (HPTA) on serum transaminase and alkaline phosphatase activity in burn patients were studied, retrospectively. Temporary elevations in the activity of gamma-glutamyl transferase (GGT), aspartate aminotransferase (ASAT), alanine aminotransferase (ALAT) and alkaline phosphatase (AP) were observed in both HPTA-treated patients and their matched controls. No statistically significant difference was found between the two patient-groups with respect to the mean enzyme activities, calculated as the areas under the curve between 5 and 15 days post-burn (PBD). These results seem to indicate that HPTA does not cause hepatotoxicity, at least when applied to a burned area corresponding to approximately 10% of the total body surface. This is in agreement with the widespread and frequent use of HPTA in the food, cosmetic and pharmaceutical industries.

Effects of light on anthraquinone production in Rhamnus purshiana suspension cultures

Abstract In suspension cultures of Rhamnus purshiana, the accumulation of anthracene derivatives (i.e. 1,8-dihydroxyanthraquinones, anthrones and/or dianthrones was increased by a daily photoperiod of 12 hr. In particular the emodin (and to a lesser extent chrysophanol) content of the cultures was significantly raised by a 12 hr light/dark cycle, whereas the levels of physcion were much less affected. The formation of anthra-derivatives, however, was strongly suppressed when the cultures were continuously illuminated.

A Response to: O. Renn & M. Roco (2006). 'Nanotechnology and the Need for Risk Governance'

In the April 2006 issue of the Journal of Nanoparticle Research, Renn and Roco wrote a thorough analysis of the future of nanotechnology and the concomitant process of risk governance (Renn and Roco 2006a). Their view was based on the first white paper on risk governance of the International Risk Governance Council (IRGC) (Renn 2005) and also published as the second IRGC white paper (Renn and Roco 2006b). Approximately at the same time, the Health Council of the Netherlands published an advisory report on the health significance of nanotechnologies based on our work in an ad hoc committee (Health Council of the Netherlands 2006). In the final chapter of this report, we argued in favour of the establishment of sound procedures for democratic, scientifically informed, control and decision-making and independently proposed that the risk governance framework of the IRGC (Renn 2005) may serve this purpose. In this letter, we draw a comparison between the results of both efforts to use the IRGC’s framework in the area of nanotechnologies and comment on some of the differences and implications. In their paper, Renn and Roco identified four successive generations of nanotechnology products: passive nanostructures, active nanostructures, (large) nanosystems and molecular nanosystems, which will appear on the market mainly after 2000, 2005, 2010 and 2015/2020, respectively. The authors grouped Bijker and Van Dijk were chairman and scientific secretary, respectively, of the Committee on Nanotechnologies and Health of the Health Council of the Netherlands. The other authors were members of the committee.

BIOTECHNOLOGY AND BIOSYNTHESIS OF QUINONES

Nowadays, it is generally agreed that intensive investigation of biosynthetic pathways is a prerequisite for attaining industrial-scale production of secondary metabolites (e.g. quinones) by plant cell cultures. Literature data are presented to illustrate different aspects of todays quinone biosynthesis research.