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1.
Environ Sci Pollut Res Int ; 31(25): 37663-37680, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38780849

RESUMO

Improving energy content and hydrophobic nature of woody biomass can be pursued through torrefaction. This gives torrefied biomass with a low bulk density, potentially increasing storage and transport costs. To overcome this issue, densifying the torrefied biomass is necessary. However, poor binding of particles makes densification challenging without using a binder. Therefore, the aim of this study was to investigate the physicochemical characteristics and techno-economic aspects of torrefied rubberwood biomass (TRWB) when pelletized using various cassava-based binders at different blending ratios. The selected binders included cassava starch (CS), cassava pulp (CP), and cassava chip (CC). Each binder at 5%, 10%, or 15% (wt.) was mixed with TRWB and water before pelletizing using a flat die machine. The results revealed that pelletizing TRWB with different cassava-based binders at various blending ratios influenced the physicochemical characteristics of the TRWB pellets, particularly dimensions, bulk density, fuel and atomic ratios, and energy content. The TRWB pellets demonstrated energy densities in the range of 7.95-11.39 GJ/m3, and their mechanical durability and fine content fell within acceptable ranges. The TRWB pellets maintained their shape during 120 min of water soaking, with water absorption levels varying by binder dose. The pelletizing ability, material, and energy costs of TRWB pellets depend on binder type and dose. CP can be applied as a binder for pelletizing torrefied rubberwood biomass. However, the mechanical durability of the product needs to be above the user requirement or standard.


Assuntos
Biomassa , Manihot , Madeira , Manihot/química , Madeira/química
2.
J Food Prot ; 86(11): 100160, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37699509

RESUMO

In this study, cassava tubers cultivated in the Ewekoro cement area were investigated with the aid of Hyper Pure Germanium (HPGe) detector in order to assess the radionuclide content. Twenty-seven (27) samples of both arable soil and cassava tubers were studied at different sites to the epicenter of the mining activity. The results revealed the highest activity concentrations of K-40, Ra-226, and Th-232 to be 194.10, 63.92, and 76.90 Bq/kg, respectively, in soil to be at site 1, which was 50 m away from the cement mining site. Similarly, cassava reported the highest activity concentrations of 228.15 and 81.50 Bq/kg for K-40 and Ra-226, respectively, at sites 2, which was 150 m away from the mining site. However, the highest value of Th-232 in cassava was noted in site 1. Also, the highest values of Raeq for arable soil and cassava tubers were estimated to be 188.84 Bq/kg and 199.89 Bq/kg at site 1 and site 2, respectively. All the above results were higher than the recommended safe limits by a factor of 2. Moreover, the Total Annual Effective Dose of exposure by oral ingestion of cassava tubers for different age groups revealed children to have the highest level of exposure with the highest mean value of 7.98 mSv. This is followed by adults and infants, which reported 5.66 and 5.38 mSv, respectively, all at site 2. This result is far greater than the recommended safe limits of 1 mSv. Therefore, the results of the total averages of annual effective doses due to consumption of the three natural radionuclides in cassava tubers and other products from it by adults, children, and infants were found to be above the average annual ingestion radiation dose due to natural sources. Further statistical analysis of the results showed significant differences between sites 1 and 2 and between sites 1 and 3, where there was no statistically significant difference between sites 2 and 3.


Assuntos
Manihot , Monitoramento de Radiação , Rádio (Elemento) , Poluentes Radioativos do Solo , Criança , Humanos , Rádio (Elemento)/análise , Monitoramento de Radiação/métodos , Radioisótopos/análise , Solo , Poluentes Radioativos do Solo/análise , Radioisótopos de Potássio/análise , Tório/análise
3.
Sci Rep ; 13(1): 16295, 2023 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-37770493

RESUMO

The growing global market for industrial enzymes has led to a constant search for efficient, cost-effective methods for their production. This study reports the production of invertase using inexpensive and readily available agro-materials. Starch-digesting enzymes extracted from malted unkilned sorghum were used to hydrolyze cassava starch supplemented with 2% whole soybean. The production of intracellular invertase by Saccharomyces cerevisiae OL629078.1 in cassava-soybean and yeast sucrose broth was compared. The purification and characterization of invertase produced using the low-cost medium were also reported. The results showed that there was a 4.1-fold increase in the units of invertase produced in cassava-soybean medium (318.605 U/mg) compared to yeast sucrose broth medium (77.6 U/mg). The invertase produced was purified by chromatographic methods up to 5.53-fold with a recovery of 62.6%. Estimation of the molecular weight with gel filtration indicated a molecular weight of 118 kDa. The enzyme demonstrated its maximum activity at 50 °C and there was no decrease in its activity following a 1-h incubation at this temperature. At a pH of 5.0, the enzyme demonstrated optimal activity and it maintained over 60% of its activity in the acid range (pH 3-6). The Michalis-Menten constants Km and Vmax of intracellular invertase were 5.85 ± 1.715 mM and 6.472 ± 2.099 U/mg, respectively. These results suggest that Saccharomyces cerevisiae grown on cassava-soybean is a viable, cost-effective alternative for commercial invertase production, which can be explored for biotechnological processes.


Assuntos
Manihot , beta-Frutofuranosidase , beta-Frutofuranosidase/química , Saccharomyces cerevisiae , Glycine max , Análise Custo-Benefício , Sacarose , Amido
4.
Value Health Reg Issues ; 38: 77-84, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37619437

RESUMO

OBJECTIVES: Vitamin A deficiency is the leading cause of childhood blindness worldwide, affecting mostly Sub-Saharan Africa. We aimed to predict the cost-effectiveness of home gardening (HG) of yellow cassava and orange maize to prevent nutritional blindness in children below 5 years and to assess the likely value of obtaining additional information in reducing uncertainty surrounding its cost-effectiveness. METHODS: We developed a Markov model and carried out probabilistic sensitivity analysis with a value of information analysis. We costed resources from a societal perspective and outcomes were measured in disability-adjusted life years (DALYs). RESULTS: HG was estimated to cost an additional Intl$395.00 per DALY averted, with a 72.27% likelihood of being cost-effective at a threshold of Intl$2800 per DALY. The expected value of information was estimated to be Intl$29 843.50 for 1 child or Intl$925 billion for 31 million Nigerian children affected by the decision. Further research is only worthwhile for 1 parameter (relative risk of low serum retinol; expected value of perfect parameter information Intl$29 854.53 per child and Intl$925 billion for 31 million children). CONCLUSION: HG of yellow cassava and orange maize is expected to be highly cost-effective in preventing nutritional blindness in Nigerian children. Worthwhile further research includes a cost analysis of the intervention and a high-quality randomized trial to assess the effectiveness of HG on serum retinol levels in young children.


Assuntos
Manihot , Humanos , Criança , Pré-Escolar , Análise Custo-Benefício , Zea mays , Jardinagem , Vitamina A/uso terapêutico
5.
Environ Monit Assess ; 195(4): 482, 2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-36930367

RESUMO

Improper discharge of cassava mill effluent (CME) has attracted much attention in major cassava-producing areas due to cyanide contamination. This study conducted a target survey on inhabitants and processors of the Akrofrom-Techiman cassava processing area in Ghana that aimed to assess their knowledge and perception of cyanide contamination from the CME discharge. The study further examined the effect of CME on the soil and groundwater at the processing area using physicochemical and bacteriological characterizations. Results revealed that inhabitants and processors exhibited high illiteracy on the impact of CME on cyanide contamination in the processing area. The study also indicated a wide characteristics of the soil at the processing site: pH (4.89-8.77), electrical conductivity (EC) (1063.00-1939.00 µS/cm), total dissolved solids (TDS) (523.90-963.50 mg/L), soil moisture (11.90-31.70%), free cyanide (0.02-0.33 mg/kg), and total cyanide (0.40-2.70 mg/kg). Results also showed that the physicochemical values of the CME were all above the Ghana Environmental Protection Agency (EPA) permissible limits and were unsafe for discharging into the environment. The range of physicochemical and bacteriological parameters of the two boreholes revealed the following: pH (7.85-8.74), TDS (165.77-192.37 mg/L), EC (320.87-396.20 µS/cm), free cyanide (0.13-0.16 mg/L), total cyanide (1.29-2.15 mg/L), and bacteriological parameter (220-622 cfu/mL). The two hand-dug wells also recorded pH (8.54-9.56), TDS (140.77-156.10 mg/L), EC (288.53-340.67), biological oxygen demand (BOD) (21.51-1.61 mg/L), chemical oxygen demand (COD) (13.5-16.5 mg/L), free cyanide (0.10-0.11 mg/L), bacteriological parameter (241-302 cfu/mL), and total cyanide (0.79-0.86 mg/L). The study concluded that the discharge of CME at the processing site contributes significantly to cyanide contamination of the soil and groundwater at the processing area.


Assuntos
Água Subterrânea , Manihot , Poluentes Químicos da Água , Cianetos , Monitoramento Ambiental , Gana , Poluentes Químicos da Água/análise , Solo
6.
Environ Technol ; 44(28): 4313-4323, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35722802

RESUMO

The agricultural industries generate lignocellulosic wastes that can be modified by fungi to generate high value-added products. This work aimed to analyze the efficiency and the cost-effectiveness of the bioconversion of sugarcane and cassava bagasses using low-cost homemade enzymatic cocktails from Aspergillus niger LBM 134. Both bagasses were pretreated with a soft alkaline solution without any loss of polysaccharides. After the hydrolysis, a 28% of conversion to glucose and 42% to xylose were reached in the hydrolysis of sugarcane bagasse while an 80% of saccharification yield, in the hydrolysis of cassava bagasse using the homemade enzymes. Furthermore, a more disorganised surface and no starch granules were observed in the sugarcane and cassava bagasses, respectively. The bioethanol yield from sugarcane and casava bagasses was predicted to be 4.16 mg mL-1 and 2.57 mg mL-1, respectively. A comparison of the cost of the homemade and the commercial enzymes was carried out. Similar hydrolysis percentages were achieved employing any enzyme; however, it was 1000-2000 times less expensive using the homemade cocktails than using the commercial enzymes. Therefore, the cost of obtaining glucose from bagasses was most expensive when applying the commercial enzymes. Moreover, the hydrolysis of the cassava bagasse was most efficient with the homemade cocktails. The importance and novelty of this work lie in the similar performance and the lower cost of the homemade cocktails from the fungus A. niger LBM 134 compared with the commercial enzymes on the hydrolysis of the sugarcane and cassava bagasses.


Assuntos
Manihot , Saccharum , Celulose , Glucose , Fungos , Hidrólise
7.
Rapid Commun Mass Spectrom ; 37(2): e9426, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36329665

RESUMO

RATIONALE: Cassava production faces challenges in a changing climate. Pulse labelling cassava with 13 C-CO2 has the potential to elucidate carbon allocation mechanisms of cassava under drought stress and with potassium application. Understanding these mechanisms could guide efforts to mitigate effects of drought in cassava cropping systems. METHODS: Forty-eight cassava plants received a nutrient solution high or low in potassium. Water deficit was imposed on half of the plants at bulk root initiation stage, after which they were labelled for 8 h with 13 C-CO2 in a 15 m3 growth chamber. Plants were harvested 8 h, 9 days and 24 days after labelling, and separated into leaves, stems and roots. δ13 C values of the different parts were measured using an isotope ratio mass spectrometer, from which 13 C excess was calculated. RESULTS: Water deficit decreased transpiration (P < 0.001) and increased carbon respiration (P < 0.05). Potassium application increased assimilate distribution to the roots (P < 0.05) at 9 days after labelling, more strongly for plants under water deficit. The opposite was found at 24 days (P < 0.05) with the legacy of water deficit additionally increasing assimilate distribution to roots (P < 0.05). Youngest, fully expanded leaves contained up to 47% of initial 13 C excess at 24 days after labelling. CONCLUSIONS: Pulse labelling proved to be successful in shedding light on carbon allocation in relation to water and potassium availability. This technique, once adapted to field conditions, could further be used to improve fertilizer recommendations or change agronomic practices to cope with plant stress.


Assuntos
Manihot , Carbono , Água , Dióxido de Carbono , Potássio , Folhas de Planta , Raízes de Plantas
8.
Sci Rep ; 12(1): 20598, 2022 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-36446810

RESUMO

Cassava cultivation causes serious soil fertility depletion in southern Cameroon due to high mining of soil nutrients by the crop. This study aimed to evaluate the effects of Tithonia diversifolia fresh biomass (TB), poultry manure (PM) and inorganic fertilizers (IF) on soil properties, cassava yield, and the economic returns. The treatments consisted of two rates of TB (10 and 20 t ha-1), two rates of PM (10 and 20 t ha-1), two rates of combined TB and PM (5 and 10 t ha-1), a single rate of inorganic fertilizers (100 N:22P:83 K kg ha-1) and a control. The results showed that soil properties, soil quality index and cassava yield were significantly improved by the application of the organic manures. Tithonia diversifolia fresh biomass (TB) and poultry manure (PM) lowered the soil bulk density, increased soil total porosity, water holding capacity and chemical properties. TB and PM, solely or mixed, improved the aerial dry biomass (ADB) and fresh tuber yield (FTY) of cassava. The organic manures performed better than inorganic fertilizer. The highest yield (51 and 52 t ha-1 of fresh tubers) was obtained with the mixture of TB and PM applied at 10 t ha-1 each for the successive years. Positive and significant correlation was found between SQI and cassava yield. TB and PM combined at 10 t ha-1 each was the most profitable and cost-effective treatment, with a good benefit:cost ratio of 3.2:1 and net return of FCFA 3.736.900 ha-1. Thus, the use of Tithonia diversifolia fresh biomass and poultry manure is a sustainable method for cassava production in the southern Cameroon.


Assuntos
Fertilizantes , Manihot , Esterco , Solo , Camarões , Verduras
9.
Trop Anim Health Prod ; 54(4): 226, 2022 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-35796806

RESUMO

The pineapple stem starch substituted for ground cassava or corn as a carbohydrate source in the concentrate diet. The experiment used 36 Holstein crossbred steers (aged 22 months) with an average initial body weight of 453.0 ± 35.3 kg. The experimental units were randomly assigned to three different starch sources of concentrate diets: ground corn (GC), ground cassava (CA), or pineapple stem starch (PS) with two different feeding periods: (1) period 1 for 206 days or (2) period 2 for 344 days with six replicates per treatment (two steers per replication), arranged in a completely randomized design. The animals were slaughtered at the end of the experimental periods. After that, the feedlot performance, carcass characteristics, meat quality, and economic return were evaluated. The results showed that the steers fed PS had a greater weight gain, average daily gain, and lower feed: gain ratio when fed for 206 days than when fed for 344 days, but dry matter intake, carcass characteristics, meat quality, and fatty acids profile did not differ between treatments in both periods of feeding except C14:1 and C18:0. The steers fed PS showed the greatest economic return. As a substitute for cassava or corn, pineapple stem starch had no negative impact on the feedlot performance, carcass characteristics, and meat quality. These results indicate that pineapple stem starch could be a useful feedstuff for the feedlot steers diets as an alternative starch source.


Assuntos
Ananas , Manihot , Ração Animal/análise , Animais , Composição Corporal , Bovinos , Análise Custo-Benefício , Dieta/veterinária , Carne , Amido , Verduras , Zea mays
10.
An Acad Bras Cienc ; 94(4): e20201735, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35830071

RESUMO

The environmental and health risks associated with the application of synthetic chemical inputs in agriculture increased the demand for technologies that allow higher performance and quality of vegetable crops by implementing synergistic materials with the principles of sustainability. In this work, the seed coating with the biomass of Dunaliella salina incorporated in a bioplastic film of Manihot esculenta (cassava) was evaluated as an initial growth and secondary compounds stimulator of Coriandrum sativum (coriander) plants. The obtained results demonstrated that the coating stimulated an increase in the germination percentage (28.75%) and also in concentration of bioactive compounds, such as the six-fold increment of caffeic acid (13.33 mg 100 g-1). The carbohydrates, lipids, and proteins present in the microalgae biomass seem to be responsible for these increments once they are known for providing energy to the seedling development and coordinating the secondary metabolites synthesis. As conclusion, we consider the coating with biomass of D. salina an alternative for crop improvement that contributes to the development of sustainable agricultural practices.


Assuntos
Biomassa , Clorofíceas , Coriandrum , Microalgas , Desenvolvimento Vegetal , Metabolismo Secundário , Sementes , Ácidos Cafeicos , Carboidratos , Clorofíceas/química , Coriandrum/química , Coriandrum/efeitos dos fármacos , Coriandrum/crescimento & desenvolvimento , Coriandrum/metabolismo , Produção Agrícola/métodos , Lipídeos , Manihot/química , Microalgas/química , Desenvolvimento Vegetal/efeitos dos fármacos , Metabolismo Secundário/efeitos dos fármacos , Sementes/química , Sementes/efeitos dos fármacos , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Desenvolvimento Sustentável
11.
Environ Sci Pollut Res Int ; 29(5): 6722-6732, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34462850

RESUMO

Using post-mining areas for planting energy crops has emerged as a promising and sustainable reclamation solution due to its potential contributions to environmental protection, land restoration, and especially energy security. However, to ensure the sustainability of this reclamation solution, its environmental performance needs to be thoroughly assessed case by case. Located in Ha Thuong Commune, Dai Tu District, Thai Nguyen Province in northern Vietnam, Nui Phao is the world's largest tungsten mine. To restore post-mining sites at Nui Phao, cassava planting for ethanol production was one of the proposed measures. To support the decision-making, this study employs life cycle assessment to thoroughly evaluate the environmental performance and potential environmental benefits/costs of cassava-based reclamation system in terms of resource consumption and green house gas (GHG) emission. The results show that cassava-based reclamation might bring significant environmental benefits in terms of fossil fuel saving and GHGs reduction (i.e., reduce 50% fossil fuel consumption and 36% GHGs emission); however, it does not bring any benefit in terms of water and land resource consumption. Moreover, the results define cassava cultivation as the "hot spot" of the system, where innovations to enhance the yield and reduce water and fertilizer consumption are required to improve the environmental performance of the cassava-based reclamation system.


Assuntos
Manihot , Animais , Produtos Agrícolas , Estágios do Ciclo de Vida , Mineração , Vietnã
12.
Trop Anim Health Prod ; 54(1): 5, 2021 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-34890021

RESUMO

Two experiments were carried out to evaluate the effect of mixed cassava pulp and napier grass (MCN) supplemented with multi-component enzymes on the hen performance and egg quality as well as nutrient digestibility. In experiment 1, forty laying hens (Isa Brown) of 34 weeks in age were randomly allotted to 5 groups: control and 5, 10, 15, and 20% MCN for 10 days (one bird per cage, eight cage replicates). The results indicated that dry matter, and organic matter digestibilities, or nitrogen retention (P > 0.05) showed no significant alteration when used MCN up to 20%. In experiment 2, one hundred and eighty Isa Brown laying hens of 67 weeks in age were randomly assigned to 5 groups (control and 4 MCN: 5, 10, 15, and 20%) and raised for 8 weeks. It revealed that the inclusion rate of MCN up to 20% did not affect the productive performance, plasma cholesterol concentration, cecal microbial populations, or ammonia production (P > 0.05). In addition, egg yolk cholesterol was found to be lower in laying hens fed 20% MCN compared to 5% MCN (P < 0.05), but no significant differences compared to the control. In conclusion, it is indicated that MCN can be used as a partial part of an energy source in laying hen diets with no adverse effects on productive performance, nutrient digestibility or egg quality.


Assuntos
Manihot , Ração Animal/análise , Animais , Galinhas , Dieta/veterinária , Óvulo
13.
Health Technol Assess ; 25(61): 1-102, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34751645

RESUMO

BACKGROUND: Around 60,000 babies are born preterm (prior to 37 weeks' gestation) each year in the UK. There is little evidence on the optimal birth mode (vaginal or caesarean section). OBJECTIVE: The overall aim of the CASSAVA project was to determine if a trial to define the optimal mode of preterm birth could be carried out and, if so, determine what sort of trial could be conducted and how it could best be performed. We aimed to determine the specific groups of preterm women and babies for whom there are uncertainties about the best planned mode of birth, and if there would be willingness to recruit to, and participate in, a randomised trial to address some, but not all, of these uncertainties. This project was conducted in response to a Heath Technology Assessment programme commissioning call (17/22 'Mode of delivery for preterm infants'). METHODS: We conducted clinician and patient surveys (n = 224 and n = 379, respectively) to identify current practice and opinion, and a consensus survey and Delphi workshop (n = 76 and n = 22 participants, respectively) to inform the design of a hypothetical clinical trial. The protocol for this clinical trial/vignette was used in telephone interviews with clinicians (n = 24) and in focus groups with potential participants (n = 13). RESULTS: Planned sample size and data saturation was achieved for all groups except for focus groups with participants, as this had to be curtailed because of the COVID-19 pandemic and data saturation was not achieved. There was broad agreement from parents and health-care professionals that a trial is needed. The clinician survey demonstrated a variety of practice and opinion. The parent survey suggested that women and their families generally preferred vaginal birth at later gestations and caesarean section for preterm infants. The interactive workshop and Delphi consensus process confirmed the need for more evidence (hence the case for a trial) and provided rich information on what a future trial should entail. It was agreed that any trial should address the areas with most uncertainty, including the management of women at 26-32 weeks' gestation, with either spontaneous preterm labour (cephalic presentation) or where preterm birth was medically indicated. Clear themes around the challenges inherent in conducting any trial emerged, including the concept of equipoise itself. Specific issues were as follows: different clinicians and participants would be in equipoise for each clinical scenario, effective conduct of the trial would require appropriate resources and expertise within the hospital conducting the trial, potential participants would welcome information on the trial well before the onset of labour and minority ethnic groups would require tailored approaches. CONCLUSION: Given the lack of evidence and the variation of practice and opinion in this area, and having listened to clinicians and potential participants, we conclude that a trial should be conducted and the outlined challenges resolved. FUTURE WORK: The CASSAVA project could be used to inform the design of a randomised trial and indicates how such a trial could be carried out. Any future trial would benefit from a pilot with qualitative input and a study within a trial to inform optimal recruitment. LIMITATIONS: Certainty that a trial could be conducted can be determined only when it is attempted. TRIAL REGISTRATION: Current Controlled Trials ISRCTN12295730. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 25, No. 61. See the NIHR Journals Library website for further project information.


Around 60,000 babies are born preterm each year in the UK. We do not know what the safest mode of birth is for these babies. Birth options include a vaginal birth or a caesarean section (which involves an operation for the mother). Normally, the ideal way to find out what clinical options are best is to carry out a 'randomised trial' in which participants are allocated to a particular treatment group (in this case, vaginal birth or caesarean section) by chance. It is not clear if women who have their babies preterm would want to take part in such a trial or that the clinicians looking after the women would be happy to ask them to, as previous trials have failed to recruit sufficient participants. The purpose of the CASSAVA research project was to find out what people think is the best and safest method of delivering preterm babies, their views on doing a research trial and what sort of research trial could be carried out. We conducted a survey asking clinicians and women their views. We gathered clinicians and women together to discuss and agree the key questions for a trial to answer. We then developed a protocol (plan) for a possible trial. Using this trial protocol, we conducted telephone interviews with clinicians, asking them if they would be willing to be involved and if they would be willing to ask pregnant women to participate. We also conducted focus groups with women, using a vignette (storyboard) about a possible trial. We found that there is a lot of uncertainty about the best way for preterm babies to be born. Clinicians and women broadly agreed that it would be good to resolve this uncertainty through a trial. We were able to identify some areas of the greatest uncertainty where clinicians and women would consider participating in a study. We gained a lot of useful information about how we could best set up a trial and support clinicians and women to get involved.


Assuntos
COVID-19 , Manihot , Nascimento Prematuro , Cesárea , Estudos de Viabilidade , Humanos , Lactente , Recém-Nascido , Recém-Nascido Prematuro , Pandemias , Gravidez , Nascimento Prematuro/epidemiologia , SARS-CoV-2
14.
Bioresour Technol ; 341: 125795, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34523570

RESUMO

The generation of agroindustrial byproducts is rising fast worldwide. The slaughter of animals, the production of bioethanol, and the processing of oil palm, cassava, and milk are industrial activities that, in 2019, generated huge amounts of wastewaters, around 2448, 1650, 256, 85, and 0.143 billion liters, respectively. Thus, it is urgent to reduce the environmental impact of these effluents through new integrated processes applying biorefinery and circular economy concepts to produce energy or new products. This review provides the characteristics of some of the most important agro-industrial wastes, including their physicochemical composition, worldwide average production, and possible environmental impacts. In addition, some alternatives for reusing these materials are addressed, focusing mainly on energy savings and the possibilities of generating value-added products. Finally, this review considers recent research and technological innovations and perspectives for the future.


Assuntos
Manihot , Águas Residuárias , Animais , Resíduos Industriais , Indústrias
15.
Int J Biol Macromol ; 186: 544-553, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34273338

RESUMO

In this study, cost-effective substrates such as cassava starch, corn steep liquor (CSL) and soybean meal hydrolysate (SMH) were used for pullulan production by Aureobasidium pullulans CCTCC M 2012259. The medium was optimized using response surface methodology (RSM) and artificial neural network (ANN) approaches, and analysis of variance indicated that the ANN model achieved higher prediction accuracy. The optimal medium predicted by ANN was used to produce high molecular weight pullulan in high yield. SMH substrates increased both biomass and pullulan titer, while CSL substrates maintained higher pullulan molecular weight. Results of kinetic parameters, key enzyme activities and intracellular uridine diphosphate glucose contents revealed the physiological mechanism of changes in pullulan titer and molecular weight using different substrates. Economic analysis of batch pullulan production using different substrates was performed, and the cost of nutrimental materials for CSL and SMH substrates was decreased by 46.1% and 49.9%, respectively, compared to the control using glucose and yeast extract as substrates, which could improve the competitiveness of pullulan against other polysaccharides in industrial applications.


Assuntos
Aureobasidium/enzimologia , Glucanos/metabolismo , Glycine max/metabolismo , Microbiologia Industrial , Manihot/metabolismo , Amido/metabolismo , Zea mays/metabolismo , Análise Custo-Benefício , Glucanos/economia , Microbiologia Industrial/economia , Cinética , Manihot/economia , Peso Molecular , Redes Neurais de Computação , Amido/economia
16.
Nat Commun ; 12(1): 4505, 2021 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-34301941

RESUMO

By structuring farmers' informal networks of seed exchange, kinship systems play a key role in the dynamics of crop genetic diversity in smallholder farming systems. However, because many crop diseases are propagated through infected germplasm, local seed systems can also facilitate the dissemination of seedborne pathogens. Here, we investigate how the interplay of kinship systems and local networks of germplasm exchange influences the metapopulation dynamics of viruses responsible for the cassava mosaic disease (CMD), a major threat to food security in Africa. Combining anthropological, genetic and plant epidemiological data, we analyzed the genetic structure of local populations of the African cassava mosaic virus (ACMV), one of the main causal agents of CMD. Results reveal contrasted patterns of viral diversity in patrilineal and matrilineal communities, consistent with local modes of seed exchange. Our results demonstrate that plant virus ecosystems have also a cultural component and that social factors that shape regional seed exchange networks influence the genetic structure of plant virus populations.


Assuntos
Begomovirus/genética , Variação Genética , Manihot/genética , Doenças das Plantas/genética , Sementes/genética , Agricultura/métodos , Teorema de Bayes , Begomovirus/classificação , Begomovirus/fisiologia , Ecossistema , Família , Fazendeiros , Gabão , Geografia , Interações Hospedeiro-Patógeno/genética , Humanos , Manihot/classificação , Manihot/virologia , Filogenia , Doenças das Plantas/virologia , Sementes/virologia , Especificidade da Espécie
17.
J Sci Food Agric ; 101(15): 6347-6354, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33969893

RESUMO

BACKGROUND: Vacuum package storage is commonly applied to reduce postharvest deterioration in minimally processed cassava roots. However, the influence of vacuum packaging conditions on root end-use quality is poorly understood. Hence, the effects of vacuum packaged storage at ambient, refrigerated and freezing temperatures on microflora, cassava tissue structure and starch extraction by wet milling were studied. RESULTS: Vacuum packaged storage temperature strongly affected cassava root quality. Minimal adverse effects were obtained with frozen storage. With refrigerated storage, there was negligible microbial growth but some disruption of the parenchyma cell wall structure suggestive of chilling injury. With ambient temperature storage, there was considerable Lactobacilli dominated fermentation. This caused substantial cell degradation, probably due to the production of extracellular cellulolytic and other cell wall degrading enzymes. A benefit of this cell wall breakdown was that it substantially improved starch extraction with wet milling from the stored cassava pieces; by 18% with pieces that had been ambient vacuum packaged and wet milled using a 2000 µm opening screen. However, ambient temperature storage resulted in some starch granule pitting due to the action of extracellular amylases from the fermenting microorganisms. CONCLUSION: The best vacuum packaging storage conditions for minimally processed cassava depends on application and cost. For short-term storage, refrigeration would be best for vegetable-type products. For several months storage, freezing is best. For wet milling applications, this could be combined with subsequent short-term ambient temperature storage as it improves starch extraction efficiency and could reduce distribution energy costs. © 2021 Society of Chemical Industry.


Assuntos
Embalagem de Alimentos/métodos , Manihot/química , Tubérculos/química , Amido/isolamento & purificação , Manipulação de Alimentos , Embalagem de Alimentos/economia , Embalagem de Alimentos/instrumentação , Armazenamento de Alimentos , Amido/análise , Temperatura , Vácuo
18.
Food Chem ; 354: 129405, 2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-33770563

RESUMO

The intake of cassava would probably induce adverse health effects since there are toxic cyanide in cassava. However, the risk assessment of cassava consumption has not been reported in China. Therefore, this paper aimed to evaluate the dietary risks of cassava cyanide and proposed a maximum residue limit (MRL) for cyanogenic glycosides (CNGs) in cassava. The retention rate of CNGs and CN- were 61% and 11% after boiling, respectively. The acute dietary exposure of CN- and CNGs were 0.6-fold and 1.7-fold of acute risk reference dose, respectively. There was no chronic health risk across all populations concerning cassava consumption. The MRL of CNGs was proposed as 200 mg/kg in cassava. Risk assessment of cyanide for foods rich in CNGs was suggested to be based on CNGs quantification rather than that of CN-.


Assuntos
Cianetos/análise , Exposição Dietética , Manihot/química , China , Cromatografia Líquida de Alta Pressão , Culinária , Glicosídeos/análise , Humanos , Manihot/metabolismo , Raízes de Plantas/química , Raízes de Plantas/metabolismo , Medição de Risco , Espectrometria de Massas em Tandem
19.
Bioresour Technol ; 330: 124949, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33725520

RESUMO

NaHCO3 was used as a novel activator to produce cassava ethanol sludge-based biochar. The NaHCO3-activated biochar showed superior adsorption capacity for tetracycline (154.45 mg/g) than raw biochar (34.04 mg/g). Orthogonal experiments confirmed the optimal preparation conditions of biochar. Increasing adsorbent dosage and temperature facilitated tetracycline removal. The maximum removal was 92.60% at pH = 3.0. Calcium ions and alkalinity decreased tetracycline removal. The time for attaining equilibrium was extended with increasing tetracycline concentration, but the equilibrium could be completed within 24 h. Langmuir model fitted the equilibrium data well. Kinetics process followed the Elovich model. The adsorption rate was controlled by both intraparticle and liquid film diffusion and the process was endothermic and spontaneous. The electrostatic attraction, hydrogen bonding, π-π interactions, and pore-filling were involved in the adsorption mechanism. The findings may provide an underlying guide for sludge disposal and removal of tetracycline from wastewater in practical application.


Assuntos
Manihot , Poluentes Químicos da Água , Adsorção , Carvão Vegetal , Etanol , Cinética , Esgotos , Bicarbonato de Sódio , Tetraciclina , Poluentes Químicos da Água/análise
20.
Bioresour Technol ; 323: 124586, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33387712

RESUMO

Integrated processes of whole plant cassava bioethanol production using full components including cellulosic C5 sugar are proposed. The impacts of different utilization patterns of cellulosic C5 sugar on bioethanol production are investigated by life cycle assessment. Results show that for cassava straw bioethanol, process using cellulosic C5 sugar performs better, and the NER, renewability and GWP (global warming potential) are 0.94, 1.09 and 2929 kg CO2 eq. The integrated process WPC-2 that the cellulosic C5 sugar mash is fermented together with the cassava starch, is a better cellulosic C5 sugar utilization pattern with NER 1.49, renewability 2.20 and GWP 1579 kg CO2 eq. The process WPC-2 shows the potential to approach cassava bioethanol in terms of energy and environmental emissions. The downstream products are investigated and the E85 fuel from WPC-2 has higher application potential.


Assuntos
Manihot , Animais , Biocombustíveis , Etanol , Estágios do Ciclo de Vida , Açúcares
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