Abiotic Stress Effect on Agastache mexicana subsp. mexicana Yield: Cultivated in Two Contrasting Environments with Organic Nutrition and Artificial Shading.

Research on medicinal plants is essential for their conservation, propagation, resistance to environmental stress, and domestication. The use of organic nutrition has been demonstrated to improve soil fertility and plant quality. It is also important to study the effects of the Basic Cation Saturation Ratio (BCSR) approach, which is a topic where there is currently controversy and limited scientific information. Evaluating the growth and yields of Agastache mexicana subsp. mexicana (Amm) in different environments is crucial for developing effective propagation and domestication strategies. This includes examining warm and subhumid environments with rain in summer in comparison to mild environments with summer rain. Significant differences were observed in the effects of cold, waterlogging, and heat stresses on the plant's biomass yield and the morphometric-quantitative modeling by means of isolines. The biomass yield was 56% higher in environment one compared to environment two, 19% higher in environment one with organic nutrition, and 48% higher in environment two with organic nutrition compared to using only BCSR nutrition. In the second harvesting cycle, the plants in environment one did not survive, while the plants in environment two managed to survive without needing additional nutrition. Statistical and mathematical analyses provided information about the population or sample. Additionally, further analysis using isolines as a new approach revealed new insights into understanding phenology and growth issues.

Gangliocytic paraganglioma: A case report.

Paragangliomas (PGLs) are rare and encapsulated neuroendocrine tumors (NET), located in the adrenal gland or the extra-adrenal paraganglia. Extra-adrenal PGLs may develop a gangliocytic component with ganglion cells which are called gangliocytic paragangliomas (GPs). The most common location is the duodenum, and they appear with digestive symptoms or as an incidental finding. We described a 43 years old patient, with epigastric pain, nausea and vomiting. The CT-scan reveals a nodular image in the duodenum. An ultrasound-guided FNA was performed and the pathological report revealed neuroendocrine cell groups and neural tissue. Surgery was the chosen treatment. As the patient did not present lymphatic or pancreatic parenchyma invasion, radiotherapy (RT) was not administered. The management of GPs is not well established and multidisciplinary team approach is recommended to lead to therapeutic options. Surgical resection is still key in the treatment, and adjuvant RT may be considered in cases of lymph node invasion.

Fighting thyrotoxicosis with therapeutic plasma exchange: A case report.

Thyrotoxicosis is the clinical condition resulting from an excess of thyroid hormones for any reason. The main causes are Graves-Basedow disease, toxic multinodular goitre and toxic adenoma. The medical treatment to control thyroid function includes antithyroid drugs, beta blockers, iodine solutions, corticosteroids and cholestyramine. Although therapeutic plasma exchange is not generally part of the therapy, it is an alternative as a preliminary stage before the definitive treatment. This procedure makes it possible to eliminate T4, T3, TSI, cytokines and amiodarone. In most cases, more than one cycle is necessary, either daily or every three days, until clinical improvement is observed. The effect on thyrotoxicosis is temporary, with an approximate duration of 24-48h. This approach has been proposed as a safe and effective alternative when the medical treatment is contraindicated or not effective, and when there is multiple organ failure or emergency surgery is required.

[Consenso del grupo de trabajo de los trastornos de la conducta alimentaria de SENPE (GTTCA-SENPE). Evaluación y tratamiento médico-nutricional en la anorexia nerviosa. Actualización 2023]. / Consenso del grupo de trabajo de los trastornos de la conducta alimentaria de SENPE (GTTCA-SENPE). Evaluación y tratamiento médico-nutricional en la anorexia nerviosa. Actualización 2023.

Anorexia nervosa (AN) is a multifactorial disorder. A possible role of the social network and the gut microbiota in pathogenesis has been added. Exogenous shocks such as the COVID19 pandemic have had a negative impact on patients with AN. The potential medical and nutritional impact of malnutrition and/or compensatory behaviors gives rise to a complex disease with a wide range of severity, the management of which requires a multidisciplinary team with a high level of subject matter expertise. Coordination between levels of care is necessary as well as understanding how to transition the patient from pediatric to adult care is essential. A proper clinical evaluation can detect possible complications, as well as establish the organic risk of the patient. This allows caregivers to tailor the medical-nutritional treatment for each patient. Reestablishing adequate nutritional behaviors is a fundamental pillar of treatment in AN. The design of a personalized nutritional treatment and education program is necessary for this purpose. Depending on the clinical severity, artificial nutrition may be necessary. Although the decision regarding the level of care necessary at diagnosis or during follow-up depends on a number of factors (awareness of the disease, medical stability, complications, suicidal risk, outpatient treatment failure, psychosocial context, etc.), outpatient treatment is the most frequent and most preferred choice. However, more intensive care (total or partial hospitalization) may be necessary in certain cases. In severely malnourished patients, the appearance of refeeding syndrome should be prevented during renourishment. The presence of AN in certain situations (pregnancy, vegetarianism, type 1 diabetes mellitus) requires specific care. Physical activity in these patients must also be addressed correctly.

[A consensus report by the Working Group on Eating Disorders of Sociedad Española de Nutrición Clínica y Metabolismo (GTTCA-SENPE). Evaluation, medical and nutritional management of anorexia nervosa. Update 2023]. / Consenso del grupo de trabajo de los trastornos de la conducta alimentaria de SENPE (GTTCA-SENPE). Evaluación y tratamiento médico-nutricional en la anorexia nerviosa. Actualización 2023.

Introduction: Anorexia nervosa (AN) is a multifactorial disorder. A possible role of the social network and the gut microbiota in pathogenesis has been added. Exogenous shocks such as the COVID19 pandemic have had a negative impact on patients with AN. The potential medical and nutritional impact of malnutrition and/or compensatory behaviors gives rise to a complex disease with a wide range of severity, the management of which requires a multidisciplinary team with a high level of subject matter expertise. Coordination between levels of care is necessary as well as understanding how to transition the patient from pediatric to adult care is essential. A proper clinical evaluation can detect possible complications, as well as establish the organic risk of the patient. This allows caregivers to tailor the medical-nutritional treatment for each patient. Reestablishing adequate nutritional behaviors is a fundamental pillar of treatment in AN. The design of a personalized nutritional treatment and education program is necessary for this purpose. Depending on the clinical severity, artificial nutrition may be necessary. Although the decision regarding the level of care necessary at diagnosis or during follow-up depends on a number of factors (awareness of the disease, medical stability, complications, suicidal risk, outpatient treatment failure, psychosocial context, etc.), outpatient treatment is the most frequent and most preferred choice. However, more intensive care (total or partial hospitalization) may be necessary in certain cases. In severely malnourished patients, the appearance of refeeding syndrome should be prevented during renourishment. The presence of AN in certain situations (pregnancy, vegetarianism, type 1 diabetes mellitus) requires specific care. Physical activity in these patients must also be addressed correctly.

Introducción: La anorexia nerviosa (AN) es una enfermedad de origen multifactorial. Recientemente se ha sumado el papel de las redes sociales y la microbiota intestinal en la patogenia. La pandemia por COVID-19 ha tenido un impacto negativo en los pacientes con AN. La potencial afectación médica y nutricional derivada de la desnutrición o las conductas compensatorias dan lugar a una compleja enfermedad de gravedad variable, cuyo manejo precisa un equipo multidisciplinar con elevado nivel de conocimientos en la materia. Es fundamental la coordinación entre niveles asistenciales y en la transición de pediatría a adultos. Una adecuada valoración clínica permite detectar eventuales complicaciones, así como establecer el riesgo orgánico del paciente y, por tanto, adecuar el tratamiento médico-nutricional de forma individualizada. El restablecimiento de un apropiado estado nutricional es un pilar fundamental del tratamiento en la AN. Para ello es necesario diseñar una intervención de renutrición individualizada que incluya un programa de educación nutricional. Según el escenario clínico puede ser necesaria la nutrición artificial. Aunque la decisión de qué nivel de atención escoger al diagnóstico o durante el seguimiento depende de numerosas variables (conciencia de enfermedad, estabilidad médica, complicaciones, riesgo autolítico, fracaso del tratamiento ambulatorio o contexto psicosocial, entre otros), el tratamiento ambulatorio es de elección en la mayoría de las ocasiones. No obstante, puede ser necesario un escenario más intensivo (hospitalización total o parcial) en casos seleccionados. En pacientes gravemente desnutridos debe prevenirse la aparición de un síndrome de alimentación cuando se inicia la renutrición. La presencia de una AN en determinadas situaciones (gestación, vegetarianismo, diabetes mellitus de tipo 1, etc.) exige un manejo particular. En estos pacientes también debe abordarse de forma correcta el ejercicio físico.

Differences in weight loss and safety between the glucagon-like peptide-1 receptor agonists: A non-randomized multicenter study from the titration phase.

INTRODUCTION: Obesity increases the risk of type 2 diabetes mellitus and cardiovascular disease (CVD). Weight loss (≥5 %) reduces the risk of CVD. Glucagon-like peptide-1 receptor agonists (GLP1 RA) have shown clinically weight loss. OBJECTIVES: 1) To assess differences in the efficacy of weight loss and HbA1c; 2) to evaluate the safety and adherence during the titration phase. METHODS: It is a multicenter, prospective, and observational study on GLP1 RA naïve patients. The primary end point was the weight loss (≥5 %). Changes in weight, BMI and HbA1c were also calculated as co-primary endpoints. Secondary endpoints were safety, adherence, and tolerance. RESULTS: Among 94 subjects, 42.4 % received dulaglutide, 29,3 % subcutaneous semaglutide, 22,8 % oral semaglutide. 45 % female and the mean age was 62. Baseline characteristics were body weight 99.3 kg, BMI 36.7 kg/m2 and Hba1c 8.2 %. Oral semaglutide achieved the highest reduction: 61.1 % of patients achieving ≥ 5 %, subcutaneous semaglutide 45.8 % and dulaglutide 40.6 %. GLP1 RA significantly reduced body weight (-4.95 kg, p < 0.001) and BMI (-1.86 kg/m2, p < 0.001), without significant differences between groups. Gastrointestinal disorders were the most frequently reported events (74.5 %). 62 % of patients on dulaglutide, 25 % on oral semaglutide and 22 % on subcutaneous semaglutide. CONCLUSIONS: Oral semaglutide achieved the highest proportion of patients that lost ≥ 5 %. GLP1 RA significantly reduced BMI and HbA1c. Most of the reported adverse events were gastrointestinal disorders and they were reported in a major frequency in the dulaglutide group. Oral semaglutide would be a reasonable switch in case of future shortages.

Humans with inherited MyD88 and IRAK-4 deficiencies are predisposed to hypoxemic COVID-19 pneumonia.

X-linked recessive deficiency of TLR7, a MyD88- and IRAK-4-dependent endosomal ssRNA sensor, impairs SARS-CoV-2 recognition and type I IFN production in plasmacytoid dendritic cells (pDCs), thereby underlying hypoxemic COVID-19 pneumonia with high penetrance. We report 22 unvaccinated patients with autosomal recessive MyD88 or IRAK-4 deficiency infected with SARS-CoV-2 (mean age: 10.9 yr; 2 mo to 24 yr), originating from 17 kindreds from eight countries on three continents. 16 patients were hospitalized: six with moderate, four with severe, and six with critical pneumonia, one of whom died. The risk of hypoxemic pneumonia increased with age. The risk of invasive mechanical ventilation was also much greater than in age-matched controls from the general population (OR: 74.7, 95% CI: 26.8-207.8, P < 0.001). The patients' susceptibility to SARS-CoV-2 can be attributed to impaired TLR7-dependent type I IFN production by pDCs, which do not sense SARS-CoV-2 correctly. Patients with inherited MyD88 or IRAK-4 deficiency were long thought to be selectively vulnerable to pyogenic bacteria, but also have a high risk of hypoxemic COVID-19 pneumonia.

Impact of COVID-19 Pandemic Lockdown on Migraine Patients in Latin America.

The coronavirus (COVID-19) pandemic, confinement, fear, lifestyle changes, and worldwide health care impacted almost all diseases. Reports from countries outside Latin America revealed differences in migraine patients. In this study, we describe and compare the immediate changes in migraine symptoms associated with COVID-19 quarantine in patients from Argentina, Mexico, and Peru. An online survey was conducted from May to July 2020. The survey was answered by 243 migraine patients, with questions related to sociodemographic data, quarantine conditions, changes in working conditions, physical activity, coffee intake, healthcare access, acute migraine medication use, symptoms of anxiety, depression, and fear of COVID-19. The results show that 48.6% of migraine patients experienced worsened symptoms, 15.6% improved, and 35.8% remained unchanged. Worsening migraine symptoms were associated with staying at home during the lockdown. Intake of analgesics was associated with an increase in migraine symptoms of 18 times relative to those who did not increase their intake. Migraine symptoms improved when the number of sleep hours was increased, and we observed an improvement when patients decreased analgesic intake. The uncertainty about the end of the pandemic, the news, and social media are three items that contributed to the worsening of migraine symptoms in patients in the three investigated countries. Confinement during the first pandemic wave in Latin America harmed migraine patients who stayed home during the lockdown.

Mathematical Model for Describing Corn Grain Dehydration Kinetics after a Nixtamalization Process.

In this research, the mathematical model associated with the hydrothermal dehydration process of Nixtamalized Corn Grains (NCG) with different Steeping Time (ST) values, allows the fitting of experimental data with initial moisture M0 and the equilibrium moisture ME as a function of Isothermal Dehydration Time (IDT). The moisture percentage for any time t and dehydration rate (isolines M(t) and isolines vI respectively) of the NCG is shown by means of matrix graphics as a simultaneous function of IDT and ST. The relationship between initial dehydration rate v0 and initial moisture M0 establishes as a function of ST. Also, the mathematical model associated with the solution of the second Fick's law allows calculating the diffusivity rate vk (H2O molecules out of NCG) and verify that the rate of change in moisture and the dynamical proportionality constant k has a non-linear dependence on the IDT and that k is directly proportional to Deff. The k values strongly relate to ST and the calcium ions percentage into NCG according to solubility lime values into cooking water (or nejayote) as a function of decreasing temperature when ST increases.

[Nutritional education protocol in the treatment of eating disorders in the clinical and care settings]. / Protocolo de educación nutricional en el tratamiento de los trastornos de la conducta alimentaria en el ámbito clínico y asistencial.

INTRODUCTION: Nutrition education (NE), as part of the treatment of eating disorders (EDs), plays a crucial role in helping patients to change their food attitudes and routines, lose fears, and recover a healthy eating pattern. All these changes may contribute to improving their nutritional status. However, there is a lack of consensus and standardization concerning the procedures to teach it. This work's objective was to elaborate a consensual protocol for NE implementation in the treatment of EDs to help in decision-making regarding which patients are appropriate candidates to receive NE, the agents (family, school community) and professionals involved, and the areas in the healthcare system that are best suited for implementation. Moreover, it would help in selecting the the topics to be imparted, and in following up treatment progression.

INTRODUCCIÓN: La educación nutricional (EN), dentro del tratamiento de los trastornos de la conducta alimentaria (TCA), juega un papel fundamental ya que contribuye a que el paciente modifique sus actitudes y rutinas en relación con la comida, pierda miedos y restablezca un patrón de alimentación saludable, favoreciendo de este modo su recuperación nutricional. Sin embargo, existe falta de consenso y estandarización acerca de los procedimientos para llevarla a cabo. El objetivo de este trabajo es elaborar un protocolo consensuado de EN en el contexto del tratamiento de los TCA que permita ayudar a la toma de decisiones sobre: los pacientes candidatos a recibirla, los agentes (familia, comunidad escolar) y profesionales implicados, los ámbitos de implementación de la intervención, la información sobre los pacientes que es necesario conocer, los temas, objetivos y contenidos a trabajar, y la necesidad de evaluación de la progresión del paciente y los programas desarrollados.

Impact of Systemic Corticosteroids on Mortality in Older Adults With Critical COVID-19 Pneumonia.

BACKGROUND: The most susceptible population group to critical and fatal coronavirus disease 2019 (COVID-19) is older adults. In severe acute respiratory syndrome coronavirus 2 infection, the host immune response is thought to play a key role in the pathophysiological effects of lung damage. Therefore, corticosteroid therapy could modulate inflammation-mediated pulmonary injury and thereby reduce progression to severe respiratory failure and death. The aim of this study was to analyze the safety and clinical efficacy of corticosteroid therapy in older adults with severe COVID-19 pneumonia. METHOD: We reviewed the clinical records of confirmed COVID-19 patients aged 75 years or older admitted to our hospital over a 3-month period (March 1-May 31, 2020). A total of 143 patients were included in the study cohort. From 2 April, 2020, in accordance with World Health Organization guidance on COVID-19, our hospital protocol added corticosteroid for COVID-19 treatment. We compared in-hospital mortality among patients with critical COVID-19 who received corticosteroids therapy and those who did not. RESULTS: In total, 88 patients (61.5%) were treated with corticosteroids, and 55 patients (38.4%) were not. Both groups were similar in baseline characteristics. The median age was 85 years (interquartile range: 82-89), and 61.5% (88/143) were male. In-hospital mortality was lower in the corticosteroid group (68.2%) compared with patients in the noncorticosteroid group (81.8%). Treatment with corticosteroids was an independent survival factor (hazard ratio: 0.61; 95% CI: 0.41-0.93; p = .006). CONCLUSIONS: In critically ill older adults with COVID-19 pneumonia, the use of corticosteroid treatment resulted in lower mortality without severe adverse events.

Costs of the management of hemophilia A with inhibitors in Spain.

Introduction: Emicizumab is a first-in-class monoclonal antibody, recently authorized for the treatment of hemophilia A with inhibitors. This study aims to estimate the direct and indirect costs of the management of hemophilia A with inhibitors, in adult and pediatric patients, including the prophylaxis with emicizumab. Methods: We calculated the costs of the on-demand and prophylactic treatments with bypassing agents (activated prothrombin complex concentrate and recombinant activated factor VII) and the emicizumab prophylaxis, from the societal perspective, over 1 year. The study considered direct healthcare costs (drugs, visits, tests, and hospitalizations), direct non-healthcare costs (informal caregivers), and indirect costs (productivity loss). Data were obtained from a literature review and were validated by an expert group. Costs were expressed in 2019 euros. Results: Our results showed that the annual costs of the prophylactic treatment per patient varied between €543,062.99 and €821,415.77 for adults, and €182,764.43 and €319,826.59 for children, while on-demand treatment was €532,706.84 and €789,341.91 in adults, and €167,523.05 and €238,304.71 in pediatric patients. In relation to other prophylactic therapies, emicizumab showed the lowest costs, with up to a 34% and 43% reduction in the management cost of adult and pediatric patients, respectively. It reduced the bleeding events and administration costs, as this drug is less frequently administered by subcutaneous route. Emicizumab prophylaxis also decreased the cost of other healthcare resources such as visits, tests, and hospitalizations, as well as indirect costs. Conclusion: In comparison to prophylaxis with bypassing agents, emicizumab reduced direct and indirect costs, resulting in cost savings for the National Health System and society.

n-Iterative Exponential Forgetting Factor for EEG Signals Parameter Estimation.

Electroencephalograms (EEG) signals are of interest because of their relationship with physiological activities, allowing a description of motion, speaking, or thinking. Important research has been developed to take advantage of EEG using classification or predictor algorithms based on parameters that help to describe the signal behavior. Thus, great importance should be taken to feature extraction which is complicated for the Parameter Estimation (PE)-System Identification (SI) process. When based on an average approximation, nonstationary characteristics are presented. For PE the comparison of three forms of iterative-recursive uses of the Exponential Forgetting Factor (EFF) combined with a linear function to identify a synthetic stochastic signal is presented. The one with best results seen through the functional error is applied to approximate an EEG signal for a simple classification example, showing the effectiveness of our proposal.

A complexity scale for clinical trials from the perspective of a pharmacy service.

OBJECTIVE: To establish a method for evaluating the complexity of clinical trials (CTs) from the perspective of a pharmacy service (PS) and to analyse the complexity of CTs carried out in a tertiary level hospital. METHODS: An observational, prevalence and retrospective study was carried out in a Spanish tertiary level hospital during the period 2008-2013. A scale of complexity was developed, whose internal consistency was determined by Cronbach's alpha. The study involved five steps: an analysis of the activities involved, score allocation to the activities, identification of CTs started in the study period, data collection and assessment of the complexity. Three complexity levels were determined: low, medium and high. The variables calculated were mean overall complexity, mean complexity per medical specialty, per pathology, per phase of CT, per initiation year and percentage of CTs by complexity level. RESULTS: Cronbach's alpha of the scale of complexity was 0.738. The two most influential items were dose preparation and number of professionals involved. 55.0% of CTs were in the medium level of complexity and 12.1% of CTs were in the high level. The mean complexity of CTs studied was 13.3±4.7 (median 12, range 6-32). Statistically significant differences were found in the complexity values between CTs of different medical specialties, pathologies, phase and dose preparation in the PS (p<0.001). CONCLUSIONS: The scale designed to evaluate the complexity of CTs had internal consistency. More than half of the CTs are in the medium level if complexity. The largest number of CTs with a high level of complexity were in rheumatology and oncology.

Implementation of Specialized Pharmaceutical Care Hospital Outpatient Clinics in a Hospital Pharmacy Department.

OBJECTIVE: To describe the organization of patient care into Specialized Pharmaceutical Care Hospital Outpatient Clinics in a Hospital Pharmacy Department, to evaluate their healthcare quality, and the quality  perceived by outpatients. METHOD: A retrospective observational study in a High-Level Hospital Pharmacy Department during three periods (years 2010, 2013 and 2016); description of  the organization at the levels of structure, human resources, material resources  and working procedures; evaluation of healthcare quality through the analysis of  three variables in terms of procedure: prior appointment compliance, waiting  time and documentation of pharmaceutical care; evaluation of quality perceived  by outpatients through a satisfaction survey; comparative statistical analysis of  means (Student's t) and proportions (Pearson's chi square). RESULTS: Fifteen (15) specialized outpatient clinics were opened and managed by 18 pharmacists; between the initial and final periods of the study (2010 vs. 2016), the compliance with previous appointments was of 61.3% vs. 88.8% (p <0001), waiting time was 27.6±12.1 vs. 12.1±5.4 minutes (p  <0.0001), documentation of pharmaceutical care in the clinical record was of  2.3% vs. 9.81% (p <0.0001), and the overall satisfaction perceived by the  patients was 6.63±2.36 vs. 9.16±1.27 (p <0.01). CONCLUSIONS: The model of Specialized Pharmaceutical Care Hospital Outpatient  Clinics exposed, focused on the patient and with continuity of care, has improved the quality of care and the quality perceived by the patients and it´s in optimal conditions to investigate its contribution on health outcomes and on the health system through a better quality, safety and efficiency of pharmacotherapy.

Objetivo: Describir la organización asistencial de Consultas Externas Monográficas de Atención Farmacéutica de un Servicio de Farmacia Hospitalaria, evaluar su calidad asistencial y la calidad percibida por los pacientes externos.Método: Estudio observacional retrospectivo en un servicio de farmacia de un hospital de nivel terciario durante tres períodos (años 2010, 2013 y 2016); descripción de la organización asistencial a nivel de estructura, recursos humanos, recursos materiales y procedimientos de trabajo; evaluación de la calidad asistencial mediante el análisis de tres variables de procedimiento: cumplimiento cita previa, tiempo de espera y documentación de la atención farmacéutica; evaluación de la calidad percibida por los pacientes externos mediante encuestas de satisfacción; análisis estadístico comparativo de  medias (t Student) y proporciones (chi cuadrado Pearson).Resultados: 15 consultas monográficas abiertas atendidas por 18 farmacéuticos; entre el período inicial y el período final del estudio (2010 vs. 2016) el cumplimiento de cita previa fue del 61,3% vs. 88,8% (p<0001), el tiempo de espera fue 27,6±12,1 vs. 12,1±5,4 minutos (p<0,0001), la documentación de la atención farmacéutica en la historia clínica del 2,3% vs. 9,81% (p<0,0001) y la satisfacción global percibida por los pacientes del 6,63±2,36 vs. 9,16±1,27 (p<0,01).Conclusiones: El modelo de Consulta Externa Monográfica de Atención Farmacéutica expuesto, centrado en el paciente y con continuidad asistencial, ha mejorado la calidad asistencial y la calidad percibida por los pacientes y se encuentra en condiciones óptimas para investigar su aportación a los resultados en salud del paciente y al sistema sanitario a través de una mejor calidad, seguridad y eficiencia de la farmacoterapia.

Extraction of Glucuronoarabinoxylan from Quinoa Stalks (Chenopodium quinoa Willd.) and Evaluation of Xylooligosaccharides Produced by GH10 and GH11 Xylanases.

Byproducts from quinoa are not yet well explored sources of hemicellulose or products thereof. In this work, xylan from milled quinoa stalks was retrieved to 66% recovery by akaline extraction using 0.5 M NaOH at 80 °C, followed by ethanol precipitation. The isolated polymer eluted as a single peak in size-exclusion chromatography with a molecular weight of >700 kDa. Analysis by Fourier transform infrared spectroscopy and nuclear magnetic resonance (NMR) combined with acid hydrolysis to monomers showed that the polymer was built of a backbone of ß(1 → 4)-linked xylose residues that were substituted by 4-O-methylglucuronic acids, arabinose, and galactose in an approximate molar ratio of 114:23:5:1. NMR analysis also indicated the presence of α(1 → 5)-linked arabinose substituents in dimeric or oligomeric forms. The main xylooligosaccharides (XOs) produced after hydrolysis of the extracted glucuronoarabinoxylan polymer by thermostable glycoside hydrolases (GHs) from families 10 and 11 were xylobiose and xylotriose, followed by peaks of putative substituted XOs. Quantification of the unsubstituted XOs using standards showed that the highest yield from the soluble glucuronoarabinoxylan fraction was 1.26 g/100 g of xylan fraction, only slightly higher than the yield (1.00 g/100 g of xylan fraction) from the insoluble fraction (p < 0.05). No difference in yield was found between reactions in buffer or water (p > 0.05). This study shows that quinoa stalks represent a novel source of glucuronoarabinoxylan, with a substituent structure that allowed for limited production of XOs by GH10 or GH11 enzymes.

Improved propionic acid production from glycerol: combining cyclic batch- and sequential batch fermentations with optimal nutrient composition.

Propionic acid was produced from glycerol using Propionibacterium acidipropionici. In this study, the impact of the concentrations of carbon and nitrogen sources, and of different modes of high cell density fermentations on process kinetics and -efficiency was investigated. Three-way ANOVA analysis and batch cultivations at varying C/N ratios at pH 6.5 revealed that propionic acid production rate is significantly influenced by yeast extract concentration. Glycerol to yeast extract ratio (ww(-1)) of 3:1 was required for complete glycerol consumption, while maintaining the volumetric productivity. Using this optimum C/N ratio for propionic acid production in cyclic batch fermentation gave propionate yield up to 93mol% and productivity of 0.53gL(-1)h(-1). Moreover, sequential batch fermentation with cell recycling resulted in production rates exceeding 1gL(-1)h(-1) at initial glycerol up to 120gL(-1), and a maximum of 1.63gL(-1)h(-1) from 90gL(-1) glycerol.