Treasure from garden: chemical profiling,pharmacology and biotechnology of mulleins

The genus Verbascum (mulleins), belonging to the family Scrophulariaceae, comprises about 360 species of flowering plants. The leaves, flowers and whole aerial parts of Verbascum spp. have been widely used in traditional medicine for the treatment of respiratory and inflammatory disorders and also display powerful wound healing activity. Verbascum species are found to accumulate several groups of bioactive molecules, therefore they might be utilized as attractive sources of new (drug) leads. The present review attempts to provide an up-to-date comprehensive overview on phytochemical and pharmacological aspects of Verbacum spp. research along with some successful examples of growing (and transforming) mulleins in vitro.     

Germ line transmission and expression of an RNAi cassette in mice generated by a lentiviral vector system

We have used a lentiviral delivery system (LentiLox3.7) to generate transgenic mice harbouring RNA interference (RNAi) against the hepatocyte nuclear factor 4 gamma (HNF4γ). HNF4γ is a nuclear receptor with unknown function. Our analyses performed on founder (F₀) and first generation (F₁) mice revealed mosaicism in F₀ founders and a low efficiency of transgenesis (6%) in F₁ mice. These data, together with the observation of multiple silenced transgenes, do not favour the use of LentiLox3.7 lentivirus for transgenesis. Despite the low efficiency of transgenesis, we achieved a tissue-dependent knockdown of HNF4γ expression in some mice. Milen Kirilov and Minqiang Chai contributed equally to this work.     

Long-acting contraceptive agents: Aliphatic and alicyclic carboxylic esters of levonorgestrel

Esters of levonorgestrel (13β-ethyl-17α-ethynyl-17β-hydroxygon-4-en -3-one) with a variety of aliphatic and alicyclic carboxylic acids have been prepared and characterised. In tests for the suppression of estrus in rats, esters with short-chain aliphatic acids and with cyclobutane-carboxylic acid were considerably more active than the standard, norethisterone enanthate (17α-ethynyl-17β-hydroxyestr-4-en-3-one). Such esters show great promise for development as long-acting progestogens.     

Bioreactors for plant cells: hardware configuration and internal environment optimization as tools for wider commercialization

Mass production of value-added molecules (including native and heterologous therapeutic proteins and enzymes) by plant cell culture has been demonstrated as an efficient alternative to classical technologies [i.e. natural harvest and chemical (semi)synthesis]. Numerous proof-of-concept studies have demonstrated the feasibility of scaling up plant cell culture-based processes (most notably to produce paclitaxel) and several commercial processes have been established so far. The choice of a suitable bioreactor design (or modification of an existing commercially available reactor) and the optimization of its internal environment have been proven as powerful tools toward successful mass production of desired molecules. This review highlights recent progress (mostly in the last 5 years) in hardware configuration and optimization of bioreactor culture conditions for suspended plant cells.     

Biotechnological production of eleutherosides: current state and perspectives

Eleutherosides, the phenylpropanoid and lignan glycosides, are the active ingredients accumulated in the roots and stems of Eleutherococcus species and in Eleutherococcus senticosus in particular. Syringin (=eleutheroside B) and (?) syringaresinol-di-O-β-d-glucoside (=eleutheroside E) appear as the most important bioactive compounds which are used as adaptogens, besides their abundant antidiabetic and anticancer properties. As the availability of “Eleuthero” is becoming increasingly limited because of its scanty natural distribution, the production of these compounds by biotechnological means has become an attractive alternative. In E. senticosus and other closely related species, Eleutherococcus sessiliflorus, Eleutherococcus chiisanensis, and Eleutherococcus koreanum, organogenic cultures have been induced for the production of eleutherosides. Bioreactor cultures have been established and various parameters, which influence on the accumulation of biomass and secondary metabolites, have been thoroughly investigated. Pilot-scale cultures have also been accomplished for the large-scale production of somatic embryos containing abundant amounts of eleutherosides. This review describes the biotechnological approaches and challenges for the production of eleutherosides.     

The Relevance of a Novel Quantitative Assay to Detect up to 40 Major Streptococcus pneumoniae Serotypes Directly in Clinical Nasopharyngeal and Blood Specimens

For epidemiological and surveillance purposes, it is relevant to monitor the distribution and dynamics of Streptococcus pneumoniae serotypes. Conventional serotyping methods do not provide rapid or quantitative information on serotype loads. Quantitative serotyping may enable prediction of the invasiveness of a specific serotype compared to other serotypes carried. Here, we describe a novel, rapid multiplex real-time PCR assay for identification and quantification of the 40 most prevalent pneumococcal serotypes and the assay impacts in pneumonia specimens from emerging and developing countries. Eleven multiplex PCR to detect 40 serotypes or serogroups were optimized. Quantification was enabled by reference to standard dilutions of known bacterial load. Performance of the assay was evaluated to specifically type and quantify S. pneumoniae in nasopharyngeal and blood samples from adult and pediatric patients hospitalized with pneumonia (n = 664) from five different countries. Serogroup 6 was widely represented in nasopharyngeal specimens from all five cohorts. The most frequent serotypes in the French, South African, and Brazilian cohorts were 1 and 7A/F, 3 and 19F, and 14, respectively. When both samples were available, the serotype in blood was always present as carriage with other serotypes in the nasopharynx. Moreover, the ability of a serotype to invade the bloodstream may be linked to its nasopharyngeal load. The mean nasopharyngeal concentration of the serotypes that moved to the blood was 3 log-fold higher than the ones only found in the nasopharynx. This novel, rapid, quantitative assay may potentially predict some of the S. pneumoniae serotypes invasiveness and assessment of pneumococcal serotype distribution.     

Bioreactor-based advances in plant tissue and cell culture: challenges and prospects

Bioreactors are engineered systems capable of supporting a biologically active situation for conducting aerobic or anaerobic biochemical processes. Stability, operational ease, improved nutrient uptake capacity, time- and cost-effectiveness, and large quantities of biomass production, make bioreactors suitable alternatives to conventional plant tissue and cell culture (PTCC) methods. Bioreactors are employed in a wide range of plant research, and have evolved over time. Such technological progress, has led to remarkable achievements in the field of PTCC. Since the classification of bioreactors has been extensively reviewed in numerous reviews, the current article avoids repeating the same material. Alternatively, it aims to highlight the principal advances in the bioreactor hardware s used in PTCC rather than classical categorization. Furthermore, our review summarizes the most significant steps as well as current state-of-the-art of PTCC carried out in various types of bioreactor.     

Hairy root type plant in vitro systems as sources of bioactive substances

“Hairy root” systems, obtained by transforming plant tissues with the “natural genetic engineer” Agrobacterium rhizogenes, have been known for more than three decades. To date, hairy root cultures have been obtained from more than 100 plant species, including several endangered medicinal plants, affording opportunities to produce important phytochemicals and proteins in eco-friendly conditions. Diverse strategies can be applied to improve the yields of desired metabolites and to produce recombinant proteins. Furthermore, recent advances in bioreactor design and construction allow hairy root-based technologies to be scaled up while maintaining their biosynthetic potential. This review highlights recent progress in the field and outlines future prospects for exploiting the potential utility of hairy root cultures as “chemical factories” for producing bioactive substances.     

Production of rosmarinic acid by<Emphasis Type="Italic">Lavandula vera</Emphasis> MM cell suspension in bioreactor: effect of dissolved oxygen concentration and agitation

The relationship between dissolved oxygen (DO) concentration, agitation rate and growth of Lavandula vera MM and rosmarinic acid biosynthesis was investigated in 3 l laboratory bioreactor. Lavandula vera MM cell suspension accumulated the highest amounts of biomass (34.8 g/l) and rosmarinic acid (1870.6 mg/l) on day 12 of cultivation at 50% dissolved oxygen and agitation speed 100 rpm and at 30% dissolved oxygen and agitation speed 300 rpm, respectively.