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Le développement de méthodes efficaces de production de carburants renouvelables à partir de la biomasse lignocellulosique est nécessaire pour maximiser les rendements et réduire les coûts d'exploitation. L'un des principaux défis de l'application industrielle du processus de conversion lignocellulosique est le coût élevé des enzymes cellulolytiques. Le recyclage des enzymes peut présenter une solution potentielle pour atténuer ce problème. Dans la présente étude, les enzymes associées à la fraction insoluble ont été recyclées après l'hydrolyse enzymatique de la bagasse de canne à sucre prétraitée, en utilisant différentes conditions de traitement, charges enzymatiques et charges solides. Il a été constaté que le mélange d'enzymes de Chrysoporthe cubensis et Penicillium pinophilum était efficace pour l'hydrolyse enzymatique et qu'une partie importante de l'activité enzymatique pouvait être récupérée lors du recyclage de la fraction insoluble. Les valeurs de productivité des enzymes (g de glucose/mg de protéine enzymatique) sur toutes les périodes de recyclage étaient de 2,4 et 3,7 pour l'application de 15 et 30 FPU/g de glucane, ce qui représente une augmentation de plus de dix fois celle obtenue dans un processus discontinu avec le même mélange d'enzymes et une augmentation encore plus importante par rapport aux enzymes cellulases commerciales. Contrairement à ce qui peut être attendu, l'augmentation des concentrations de lignine tout au long de la période de recyclage n'a pas eu d'influence négative sur l'efficacité de l'hydrolyse, mais les rendements de conversion se sont améliorés continuellement. Le recyclage de la totalité de la fraction solide insoluble était suffisant pour le recyclage des enzymes adhérées avec la biomasse, indiquant une méthode efficace pour augmenter la productivité enzymatique. El desarrollo de métodos eficientes para la producción de combustibles renovables a partir de biomasa lignocelulósica es necesario para maximizar los rendimientos y reducir los costos operativos. Uno de los principales retos para la aplicación industrial del proceso de conversión lignocelulósica son los altos costes de las enzimas celulolíticas. El reciclaje de enzimas puede presentar una posible solución para aliviar este problema. En el presente estudio, las enzimas asociadas con la fracción insoluble se reciclaron después de la hidrólisis enzimática del bagazo de caña de azúcar pretratado, utilizando diferentes condiciones de procesamiento, cargas enzimáticas y cargas sólidas. Se encontró que la mezcla enzimática de Chrysoporthe cubensis y Penicillium pinophilum fue eficiente para la hidrólisis enzimática y que una parte significativa de la actividad enzimática se pudo recuperar al reciclar la fracción insoluble. Los valores de productividad enzimática (g de glucosa/mg de proteína enzimática) durante todos los períodos de reciclaje fueron 2.4 y 3.7 para la aplicación de 15 y 30 FPU/g de glucano, lo que representa un aumento superior a diez veces el obtenido en un proceso por lotes con la misma mezcla enzimática y un aumento aún mayor en comparación con las enzimas celulasa comerciales. Contrariamente a lo que se puede esperar, el aumento de las concentraciones de lignina a lo largo del período de reciclaje no influyó negativamente en la eficiencia de la hidrólisis, pero las eficiencias de conversión mejoraron continuamente. El reciclaje de toda la fracción de sólidos insolubles fue suficiente para el reciclaje de las enzimas adheridas junto con la biomasa, lo que indica un método eficaz para aumentar la productividad enzimática. Development of efficient methods for production of renewable fuels from lignocellulosic biomass is necessary to maximize yields and reduce operating costs. One of the main challenges to industrial application of the lignocellulosic conversion process is the high costs of cellulolytic enzymes. Recycling of enzymes may present a potential solution to alleviate this problem. In the present study enzymes associated with the insoluble fraction were recycled after enzymatic hydrolysis of pretreated sugarcane bagasse, utilizing different processing conditions, enzyme loadings, and solid loadings.It was found that the enzyme blend from Chrysoporthe cubensis and Penicillium pinophilum was efficient for enzymatic hydrolysis and that a significant portion of enzyme activity could be recovered upon recycling of the insoluble fraction. Enzyme productivity values (g glucose/mg enzyme protein) over all recycle periods were 2.4 and 3.7 for application of 15 and 30 FPU/g of glucan, representing an increase in excess of ten times that obtained in a batch process with the same enzyme blend and an even greater increase compared to commercial cellulase enzymes.Contrary to what may be expected, increasing lignin concentrations throughout the recycle period did not negatively influence hydrolysis efficiency, but conversion efficiencies continuously improved. Recycling of the entire insoluble solids fraction was sufficient for recycling of adhered enzymes together with biomass, indicative of an effective method to increase enzyme productivity. يعد تطوير طرق فعالة لإنتاج الوقود المتجدد من الكتلة الحيوية اللجنية السليولوزية أمرًا ضروريًا لزيادة الغلة وتقليل تكاليف التشغيل. يتمثل أحد التحديات الرئيسية التي تواجه التطبيق الصناعي لعملية التحويل الليجنوسلوزية في ارتفاع تكاليف الإنزيمات المحللة للسليلوز. قد تقدم إعادة تدوير الإنزيمات حلاً محتملاً للتخفيف من هذه المشكلة. في هذه الدراسة، تم إعادة تدوير الإنزيمات المرتبطة بالجزء غير القابل للذوبان بعد التحلل المائي الإنزيمي لقصب قصب السكر المعالج مسبقًا، باستخدام ظروف المعالجة المختلفة، وتحميل الإنزيمات، والتحميلات الصلبة. وجد أن مزيج الإنزيم من Chrysoporthe cubensis و Penicillium pinophilum كان فعالًا في التحلل المائي الإنزيمي وأنه يمكن استرداد جزء كبير من نشاط الإنزيم عند إعادة تدوير الجزء غير القابل للذوبان. كانت قيم إنتاجية الإنزيم (جرام من بروتين إنزيم الجلوكوز/ملجم) خلال جميع فترات إعادة التدوير 2.4 و 3.7 لتطبيق 15 و 30 وحدة حماية من الحرائق/جم من الجلوكان، مما يمثل زيادة تزيد عن عشرة أضعاف تلك التي تم الحصول عليها في عملية دفعية مع نفس مزيج الإنزيم وزيادة أكبر مقارنة بإنزيمات السليلوز التجارية. على عكس ما يمكن توقعه، فإن زيادة تركيزات اللجنين طوال فترة إعادة التدوير لم تؤثر سلبًا على كفاءة التحلل المائي، ولكن كفاءة التحويل تحسنت باستمرار. كانت إعادة تدوير جزء المواد الصلبة غير القابلة للذوبان بالكامل كافية لإعادة تدوير الإنزيمات الملتصقة مع الكتلة الحيوية، مما يدل على وجود طريقة فعالة لزيادة إنتاجية الإنزيم.

In a number of African countries, the trophy hunting of large felids is an important revenue generator for landholders, governments and in some cases communities. The hunting of large felids is especially profitable but they are sensitive to harvest, as the killing of prime-aged, dominant males can lead to infanticide and lowered reproductive success. In an attempt to limit the negative impacts of trophy hunting on large felids, the scientific community has proposed a number of interventions, including age restrictions on the animals that may be hunted. Such interventions are theoretically complementary to trophy hunting, as hunters typically seek large trophies, and older animals are normally larger than younger ones in large felids. If trophy size results in an increase in trophy price, then interventions that improve average trophy size could confer elevated earnings. This is particularly true if such interventions increased the number of failed hunts such that the same tag can be sold more than once. However, if trophy size is not one of the most important factors determining the desirability of a hunt (which we judge by the price paid for a trophy hunt package), it may be more difficult to implement such schemes. It is therefore important to evaluate potential determinants of trophy hunt package price; and we examine that here for leopards (Panthera pardus) in Africa, at both the country and outfitter level. We show that Tanzania and Botswana have the most expensive package prices while South Africa has the cheapest packages. At the country level, we found no statistical relationships between package price and leopard trophy size (either through advertised website or Safari Club International (SCI) leopard trophy size), country GDP, relative hunt success, or quota size. Contrastingly, the number of charismatic species offered within a package and an index of outfitter reputation (as measured by total SCI trophy records) were positively associated with package price. Interestingly, SCI leopard trophy size was inversely correlated with package price. Our results suggest that hunters do not value leopard trophy size above other factors, which could hinder the implementation of more sustainable, age-based leopard hunting regulations.

AbstractProcess‐based models are useful for assessing the impact of changing management practices and climate on yields and greenhouse gas (GHG) emissions from agricultural systems such as grasslands. They can be used to construct national GHG inventories using a Tier 3 approach. However, accurate simulations of nitrous oxide (N2O) fluxes remain challenging. Models are limited by our understanding of soil‐plant‐microbe interactions and the impact of uncertainty in measured input parameters on simulated outputs. To improve model performance, thorough evaluations against in situ measurements are needed. Experimental data of N2O emissions under two management practices (control with typical fertilization versus increased clover and no fertilization) were acquired in a Swiss field experiment. We conducted a multimodel evaluation with three commonly used biogeochemical models (DayCent in two variants, PaSim, APSIM in two variants) comparing four years of data. DayCent was the most accurate model for simulating N2O fluxes on annual timescales, while APSIM was most accurate for daily N2O fluxes. The multimodel ensemble average reduced the error in estimated annual fluxes by 41% compared to an estimate using the Intergovernmental Panel on Climate Change (IPCC)‐derived method for the Swiss agricultural GHG inventory (IPCC‐Swiss), but individual models were not systematically more accurate than IPCC‐Swiss. The model ensemble overestimated the N2O mitigation effect of the clover‐based treatment (measured: 39–45%; ensemble: 52–57%) but was more accurate than IPCC‐Swiss (IPCC‐Swiss: 72–81%). These results suggest that multimodel ensembles are valuable for estimating the impact of climate and management on N2O emissions.

Although modern medicine is available in many developing countries, such as the Comoros Islands, the primary health-care needs of the local population are based on traditional foods and beverages derived from natural resources and medicinal plants for cultural and historical reasons. Aphloia theiformis (Vahl) Benn. (‘Mfandrabo’), Cinnamomum verum J.Presl (‘Mani yamdrara’), Ocimum gratissimum L. (‘Roulé’), Plectranthus amboinicus (Lour.) Spreng. (‘Ynadombwe’), Cymbopogon nardus (L.) Rendle (‘Sandze monach’) and Ocimum americanum L. (‘Kandza’) are six wild plants that are largely utilised to treat many diseases. The leaves of these plants are used in the traditional Comorian tea (aqueous infusion). This study aimed to identify and quantify the main health-promoting compounds in the traditional formulation of Comorian tea by HPLC profiling together with a preliminary assessment of antioxidant capacity to confirm the traditional use of these plants by the local population. The single plants were also studied. The Comoros tea presented a total polyphenolic content (TPC) of 4511.50 ± 74.41 mgGAE/100 g DW, a value higher than the TPCs of the different plants included in the Comorian tea. Moreover, the Comorian tea showed an antioxidant capacity (AOC) of 578.65 ± 6.48 mmol Fe2+/Kg DW, a value higher if compared to all the AOC values obtained in the single plants. The polyphenolic fraction (771.37 ± 35.76 mg/100 g DW) and organic acids (981.40 ± 38.38 mg/100 g DW) were the most important phytochemical classes in the Comorian tea (40.68% and 51.75% of the total phytocomplex, respectively), followed by the monoterpenes (5.88%) and vitamin C (1.67%), while carotenoids were detected in trace (0.02%). The Comorian tea could be important in meeting the high demand in the Comoros Islands and other developing countries for cost-effective and natural health-promoting foods and/or beverages to be produced by agri-food industries and used by the local population. This study may promote traditional foods in rural communities in the Comoros Islands and contribute to sustainable rural development and a commercial valorisation of these plants for health-promoting and food applications.

This study attempts to measure the capacity of the EU geographical certification scheme to positively influence the price of certified products and the incomes of their producers. A comparison of the economic results of two cheese-producing dairy farm enterprises with different business strategies and locations within the Sicilian hinterlands is performed in order to determine the transformation value of each dairy’s sheep milk into pecorino cheese (with and without the Protected Designation of Origin, or PDO, certification) and the related joint products (ricotta). The economic convenience of the total transformation of sheep milk into Pecorino Siciliano PDO and ricotta is also appraised. The results suggest that producing and commercializing Pecorino Siciliano PDO is a promising strategy for differentiating and promoting dairy farm products and improving the financial performance of producers, with foreseeable positive repercussions in the socioeconomically less favored rural areas where they are located.

Shifts in rainfall patterns and increasing temperatures associated with climate change are likely to cause widespread forest decline in regions where droughts are predicted to increase in duration and severity. One primary cause of productivity loss and plant mortality during drought is hydraulic failure. Drought stress creates trapped gas emboli in the water transport system, which reduces the ability of plants to supply water to leaves for photosynthetic gas exchange and can ultimately result in desiccation and mortality. At present we lack a clear picture of how thresholds to hydraulic failure vary across a broad range of species and environments, despite many individual experiments. Here we draw together published and unpublished data on the vulnerability of the transport system to drought-induced embolism for a large number of woody species, with a view to examining the likely consequences of climate change for forest biomes. We show that 70% of 226 forest species from 81 sites worldwide operate with narrow (<1 megapascal) hydraulic safety margins against injurious levels of drought stress and therefore potentially face long-term reductions in productivity and survival if temperature and aridity increase as predicted for many regions across the globe. Safety margins are largely independent of mean annual precipitation, showing that there is global convergence in the vulnerability of forests to drought, with all forest biomes equally vulnerable to hydraulic failure regardless of their current rainfall environment. These findings provide insight into why drought-induced forest decline is occurring not only in arid regions but also in wet forests not normally considered at drought risk.