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STUDY QUESTION What are the associations between baseline BMI (Study 1) and change in body weight (Study 2) with the likelihood of pregnancy in women with polycystic ovary syndrome (PCOS). SUMMARY ANSWER In women with PCOS, higher baseline BMI was associated with a lower chance of pregnancy; however, weight loss was associated with an increased chance of pregnancy versus maintaining a stable weight or gaining weight. WHAT IS KNOWN ALREADY Two studies in large cohorts of Danish women with the intention to become pregnant showed a decline in fecundability ratios with higher BMI. Furthermore, a meta-analysis found that overweight/obesity significantly worsened metabolic and reproductive outcomes in women with PCOS. STUDY DESIGN, SIZE, DURATION Data were extracted from the UK Clinical Practice Research Datalink GOLD database. Patients included women aged 18–45 years with BMI ≥18.5 (Study 1) or ≥25 kg/m2 (Study 2) at time of PCOS diagnosis (index date). The primary outcome was the time to first pregnancy recorded during 36-months' follow-up, analysed with Cox proportional hazard models and presented as hazard ratios (HRs). PARTICIPANTS/MATERIALS, SETTING, METHODS Study 1 included 9955 women with PCOS. Study 2 included 7593 women with PCOS and median BMI of 34.0 kg/m2. MAIN RESULTS AND THE ROLE OF CHANCE Higher BMI was associated with a lower chance of pregnancy in the 3 years following diagnosis. It was estimated that 41% of women with normal weight (18.5–24.9 kg/m2) would become pregnant compared to 17% of women with obesity class III (BMI ≥40.0 kg/m2) during follow-up. Furthermore, the chance of pregnancy for women with obesity class III was estimated to be 63% lower than for women with normal weight, with the same age and glycaemic status (HR 0.37, 95% CI 0.31–0.44; P  < 0.0001). A significant inverse association was found between BMI change and chance of pregnancy: 10% weight loss was estimated to increase the chance of pregnancy by 68% for women with baseline BMI of 40 kg/m2 (HR 1.68, 95% CI 1.49–1.90). LIMITATIONS, REASONS FOR CAUTION Multiple factors influence the chance of pregnancy (the ability and willingness to become pregnant), which was addressed by exclusion criteria employed. The real-world nature of the study means that use of non-prescription contraceptives was not available. Bias may have been introduced by the fact that only around 40% of women with PCOS in the CPRD GOLD database had their BMI recorded during the year prior to PCOS diagnosis. BMI categories used in the analyses may not be applicable to women of all ethnicities. The study population was only representative of women in the UK and results may not be generalizable to other regions. PCOS diagnoses were based on codes entered into the system by primary care providers, and no information was available regarding the criteria used for diagnosis, although symptoms used to diagnose PCOS have not changed over time. WIDER IMPLICATIONS OF THE FINDINGS Our observations provide further evidence of the benefits of weight loss in women with overweight/obesity and PCOS who are seeking to become pregnant. STUDY FUNDING/COMPETING INTEREST(S) Novo Nordisk A/S. A.H.B. declares fees for consultancy from Novo Nordisk. P.N.L. and C.L.H. are employees of Novo Nordisk. V.S. and A.V. are employees of, and hold shares in, Novo Nordisk. TRIAL REGISTRATION NUMBER N/A. [ABSTRACT FROM AUTHOR]

Microbial consortia can be used to catalyze complex biotransformations. Tools to control the behavior of these consortia in a technical environment are currently lacking. In the present study, a synthetic biology approach was used to build a model consortium of two Saccharomyces cerevisiae strains where growth and expression of the fluorescent marker protein EGFP by the receiver strain is controlled by the concentration of α‐factor pheromone, which is produced by the emitter strain. We have developed a quantitative experimental and theoretical framework to describe population dynamics in the model consortium. We measured biomass growth and metabolite production in controlled bioreactor experiments, and used flow cytometry to monitor changes of the subpopulations and protein expression under different cultivation conditions. This dataset was used to parameterize a segregated mathematical model, which took into account fundamental growth processes, pheromone‐induced growth arrest and EGFP production, as well as pheromone desensitization after extended exposure. The model was able to predict the growth dynamics of single‐strain cultures and the consortium quantitatively and provides a basis for using this approach in actual biotransformations. [ABSTRACT FROM AUTHOR]

Abstract: The ability of Kluyveromyces marxianus for converting lactose into ethyl acetate offers a chance for the economical reuse of whey. Iron plays a significant role in this process as ester synthesis requires a low intracellular iron content, xFe. The iron content in turn is decreased by growth due to cell expansion and increased by iron uptake. Thus, the iron‐uptake rate, ψ, is important for the considered process. Iron uptake by K. marxianus DSM 5422 was studied in aerobic cultivation on a whey‐borne medium with varied initial iron content, in part combined with a feed of iron under intensive growth conditions. A possible precipitation of iron that would pretend iron uptake was verified not to have occurred. Regularly measured dissolved iron concentrations, CFe,L, allowed the xFe and ψ parameters to be obtained by model‐based iron balancing. The achieved data were used for establishing a ψ(CFe,L, xFe) model. Mathematical simulations based on this iron‐uptake model reproduced the performed cultivation processes. The created iron‐uptake model allows for a future predictive system to be developed for the optimization of biotechnological ester production. [ABSTRACT FROM AUTHOR]

Abstract: Bioconversions in industrial processes are currently dominated by single‐strain approaches. With the growing complexity of tasks to be carried out, microbial consortia become increasingly advantageous and eventually may outperform single‐strain fermentations. Consortium approaches benefit from the combined metabolic capabilities of highly specialized strains and species, and the inherent division of labor reduces the metabolic burden for each strain while increasing product yields and reaction specificities. However, consortium‐based designs still suffer from a lack of available tools to control the behavior and performance of the individual subpopulations and of the entire consortium. Here, we propose to implement novel control elements for microbial consortia based on artificial cell–cell communication via fungal mating pheromones. Coupling to the desired output is mediated by pheromone‐responsive gene expression, thereby creating pheromone‐dependent communication channels between different subpopulations of the consortia. We highlight the benefits of artificial communication to specifically target individual subpopulations of microbial consortia and to control e.g. their metabolic profile or proliferation rate in a predefined and customized manner. Due to the steadily increasing knowledge of sexual cycles of industrially relevant fungi, a growing number of strains and species can be integrated into pheromone‐controlled sensor‐actor systems, exploiting their unique metabolic properties for microbial consortia approaches. [ABSTRACT FROM AUTHOR]

Oleanolic (OA) and ursolic acid (UA) are plant secondary metabolites with diverse pharmacological properties. To reach reasonable productivities with plant cell suspension cultures, elicitation is a widely used strategy. Within the presented work, the effects of different elicitors on growth and production of OA and UA in a Salvia fruticosa cell suspension culture were examined. Beside commonly used elicitors like jasmonic acid (JA) and yeast extract, the influence of medium filtrates of the endophytic fungi Aspergillus niger and Trichoderma virens was investigated. The best eliciting effects were achieved with JA and fungal medium filtrates. Both increased the triterpene content by approximately 70 %. Since JA showed significant growth inhibition, the volumetric triterpene yield did not increase. But, adding fungal filtrates increased the volumetric triterpene yield by approximately 70 % to 32.6 mg l and 65.9 mg l for T. virens compared to the control with 19.4 mg l and 33.3 mg l. An elicitation strategy combining fungal medium filtrate of T. virens with sucrose feeding significantly enhanced cell dry weight concentration to 22.2 g l as well as triterpene content by approximately 140 %. In total, this led to an approximately 500 % increase of volumetric triterpene yield referring to the control with final values of 112.9 mg l and 210.4 mg l. Despite the doubled cultivation duration, productivities of 6.7 mg l day and 12.4 mg l day were reached. These results demonstrate methods by which increased productivities of triterpenes can be achieved to attain yields competing with intact plants. [ABSTRACT FROM AUTHOR]

ABSTRACT Plant cell suspensions are frequently considered to be heterogeneous with respect to growth in terms of progression of the cells through the cell cycle and biomass accumulation. Thus, segregated data of fractions in different cycle phases during cultivation is needed to develop robust production processes. Bromodeoxyuridine (BrdU) incorporation and BrdU-antibodies or 5-ethynyl-2′-deoxyuridine (EdU) click-it chemistry are frequently used to acquire such information. However, their use requires centrifugation steps that cannot be readily applied to sensitive cells, particularly if nuclei have to be extracted from the protective cellular milieu and envelopes for DNA analysis. Therefore, we have established a BrdU-Hoechst stain quenching protocol for analyzing nuclei directly isolated from delicate plant cell suspension cultures. After adding BrdU to test Harpagophytum procumbens cell suspension cultures the cell cycle distribution could be adequately resolved using its incorporation for the following 72 h (after which BrdU slowed biomass accumulation). Despite this limitation, the protocol allows resolution of the cell cycle distribution of cultures that cannot be analyzed using commonly applied methods due to the cells' fragility. The presented protocol enabled analysis of cycling heterogeneities in H. procumbens batch cultivations, and thus should facilitate process control of secondary metabolite production from fragile plant in vitro cultures. Biotechnol. Bioeng. 2016;113: 1244-1250. © 2015 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

In this study, Nocardia iowensis was used to transform oleanolic acid (OA) into oleanane derivatives. The first derivative, which was found after 24 h of cultivation, was the known and already described OA methyl ester. After 1 week, two other derivatives (oleanonic acid methyl ester and an unknown metabolite) were identified as new products of a biotransformation by N. iowensis. These oleanane metabolites were characterized by HPLC, HPLC-ESI-MS, and HPLC-1H NMR spectroscopy. The biotransformation was performed by suspended and immobilized cells (ICs) of N. iowensis. Cells immobilized in alginate beads were used in order to prepare a continuous process. The substrate uptake of free and ICs was similar, whereas the peak area of OA methyl ester of the ICs was only about 10% of the native cells. However, the final product (oleanonic acid methyl ester) concentrations were similar in both approaches, whereas the unknown metabolite 3 was only detected transiently in the medium of ICs. Based on these results, a new biosynthetic pathway for the biotechnological production of oleanonic acid methyl ester is proposed. [ABSTRACT FROM AUTHOR]

Optimizing illumination is essential for optimizing the growth of phototrophic cells and their production of desired metabolites and/or biomass. This requires appropriate modulation of light and other key inputs and continuous online monitoring of their metabolic activities. Powerful noninvasive systems for cultivating heterotrophic organisms include shake flasks in online monitoring units, but they are rarely used for phototrophs because they lack the appropriate illumination design and necessary illuminatory power. This study presents the design and characterization of a photosynthetic shake flask unit, illuminated from below by warm white light-emitting diodes with variable light intensities up to 2300 μmol m−2 s−1. The photosynthetic unit was successfully used, in combination with online monitoring of oxygen production, to cultivate Arthrospira platensis. In phototrophic growth under continuous light and a 16 h light/8 h dark cycle (light intensity: 180 μmol m−2 s−1), the oxygen transfer rate and biomass-related oxygen production were −1.5 mmol L−1 h−1 and 0.18 mmol O2 gx−1 h−1, respectively. The maximum specific growth rate was 0.058 h−1, during the exponential growth phase, after which the biomass concentration reached 0.75 g L−1. [ABSTRACT FROM AUTHOR]

Oleanolic acid (OA) and ursolic acid (UA) are triterpenic acids with diverse biological activities that are of interest to the pharmaceutical industry. To investigate the scope for producing these compound using cell suspension cultures of Salvia species, calli from Salvia officinalis, S. virgata and S. fruticosa were induced using several plant growth regulator combinations. Eleven lines were selected for suspension induction from a pool of calli. Six suspension cultures were established successfully and cultivated in the respiration activity monitoring system (RAMOS) to obtain online data on their growth kinetics and to establish appropriate sampling schedules for the determination of their OA and UA production. Based on their observed growth behaviour, OA and UA contents, and aggregation properties, one suspension culture from each studied Salvia species was selected for further optimisation. The µ values for these suspension cultures ranged from 0.20 to 0.37 day, their OA and UA contents were greater than 1.3 and 1.2 mg g, respectively, and they afforded maximum volumetric yields of 21.0 mg l for OA and 32.8 mg l for UA. These results will be useful in the development of a refined Salvia suspension-based process for OA and UA production. [ABSTRACT FROM AUTHOR]

Extracts of Salvia species are used in traditional medicine to treat various diseases. The economic importance of this genus has increased in recent years due to evidence that some of its secondary metabolites have valuable pharmaceutical and nutraceutical properties.The bioactivity of sage extracts is mainly due to their content of terpenes and polyphenols. The increasing demand for sage products combined with environmental, ecological and climatic limitations on the production of sage metabolites from field-grown plants have led to extensive investigations into biotechnological approaches for the production of Salvia phytochemicals. The purpose of this review is to evaluate recent progress in investigations of sage in vitro systems as tools for producing important terpenoids and polyphenols and in development of methods for manipulating regulatory processes to enhance secondary metabolite production in such systems. [ABSTRACT FROM AUTHOR]

Plants produce a variety of secondary metabolites to defend themselves against herbivores or to attract pollinating insects. Plant cell biotechnology offers excellent opportunities in order to use such secondary plant metabolites to produce goods with consistent quality and quantity throughout the year, and therefore to act independently from biotic and abiotic environmental factors. This article presents results of an extensive study of plant cell in vitro cultivation in a modern shake flask system with noninvasive online respiration activity monitoring unit. Comprehensive screening experiments confirm the successful transfer of a model culture (sunflower suspension) into the shake flask monitoring device and the suitability of this respiration activity monitoring unit as qualified tool for screening of plant in vitro cultures (sunflower and sage suspension). The authors demonstrate deviations between online and offline data due to varying water evaporation from different culture flask types. The influence of evaporation on growth-specific parameters thereby rises with increasing cultivation time. Furthermore, possibilities to minimize the impact of evaporation, either by adjusting the inlet air moisture or by measuring the evaporation in combination with an appropriate correction of the measured growth values are shown. [ABSTRACT FROM AUTHOR]

cell suspension culture of Devil's claw ( Harpagophytum procumbens), a South African plant with high medicinal value, cultivated under submerged conditions showed stable growth and accumulated high amounts of biomass (18.2 g l). Flow cytometry analyses of the suspension's cell cycle kinetics showed that proportions of cells in G/G and S phases varied insignificantly (between 69-76% and 9-13%, respectively) during the cultivation, while the proportion of G/M-phase cells increased until day 8 of cultivation, when the exponential phase of cell growth ended. Metabolite production in the culture was studied through simultaneous determination of three bioactive phenylethanoid glycosides (verbascoside, β-OH-verbascoside and leucosceptoside A) by high performance liquid chromatography. It was found that suspended Devil's claw cells accumulated mainly verbascoside (517.3 mg l), followed by leucosceptoside A (107.1 mg l) and β-OH-verbascoside (80.3 mg l). In addition, several fatty acids and β-sitosterol were identified in the cell suspension by gas chromatographic-mass spectrometry analysis. Comparison of the results with previously acquired data for Harpagophytum procumbens transformed roots indicate that cell suspensions cultures are more promising as potential commercial sources of metabolites such as phenylethanoid glycosides. [ABSTRACT FROM AUTHOR]