Efficient pullulan production by Aureobasidium pullulans using cost-effective substrates.

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.

Biodegradable films based on commercial κ-carrageenan and cassava starch to achieve low production costs.

Biodegradable films have been a great alternative compared to non-renewable sources because of their cytocompatibility, biodegradability, and antimicrobial features. These properties may raise the foodstuff shelf life, reducing costs and economic losses. Indeed, biodegradable films can also reduce the environmental pollution promoted by non-biodegradable conventional packs. For the first time, biodegradable films were produced by casting commercials kappa-carrageenan (κ-car) and cassava starch at different κ-carrageenan/cassava starch weight ratios. Physical, thermal, and mechanical properties were evaluated. Apparent opacity and color analyses suggest that the films present high transparency. The sample 0κ-c supported a film with high water solubility (39.22%) and a low swelling degree (391.6%). The lowest water vapor permeability (WVP) was observed for 50κ-c (3.01×10-8g (Pams)-1). The oil permeability varied from 0.0033 to 0.0043mmm2 d-1. The 100κ-c and 75κ-c films (with high κ-carrageenan contents) had higher stiffness (19.23 and 25.88MPa, respectively) than the 25κ-c and 0κ-c films with elongation at break (ε) of 21.60 and 67.65%, respectively. The thermal stability increased as the starch concentration raised in the blend. We produced low-cost biodegradable films from commercial polysaccharides. These films can be used as food packs.

Genomic selection for productive traits in biparental cassava breeding populations.

Cassava improvement using traditional breeding strategies is slow due to the species' long breeding cycle. However, the use of genomic selection can lead to a shorter breeding cycle. This study aimed to estimate genetic parameters for productive traits based on pedigree (pedigree and phenotypic information) and genomic (markers and phenotypic information) analyses using biparental crosses at different stages of selection. A total of 290 clones were genotyped and phenotyped for fresh root yield (FRY), dry matter content (DMC), dry yield (DY), fresh shoot yield (FSY) and harvest index (HI). The clones were evaluated in clonal evaluation trials (CET), preliminary yield trials (PYT), advanced yield trials (AYT) and uniform yield trials (UYT), from 2013 to 2018 in ten locations. The breeding stages were analyzed as follows: one stage (CET), two stages (CET and PYT), three stages (CET, PYT and AYT) and four stages (CET, PYT, AYT and UYT). The genomic predictions were analyzed via k-fold cross-validation based on the genomic best linear unbiased prediction (GBLUP) considering a model with genetic additive effects and genotype × location interactions. Genomic and pedigree accuracies were moderate to high (0.56-0.72 and 0.62-0.78, respectively) for important starch-related traits such as DY and FRY; when considering one breeding stage (CET) with the aim of early selection, the genomic accuracies ranged from 0.60 (DMC) to 0.71 (HI). Moreover, the correlations between the genomic estimation breeding values of one-stage genomic analysis and the estimated breeding values of the four-stage (full data set) pedigree analysis were high for all traits as well as for a selection index including all traits. The results indicate great possibilities for genomic selection in cassava, especially for selection early in the breeding cycle (saving time and effort).

Biological control of an agricultural pest protects tropical forests.

Though often perceived as an environmentally-risky practice, biological control of invasive species can restore crop yields, ease land pressure and thus contribute to forest conservation. Here, we show how biological control against the mealybug Phenacoccus manihoti (Hemiptera) slows deforestation across Southeast Asia. In Thailand, this newly-arrived mealybug caused an 18% decline in cassava yields over 2009-2010 and an escalation in prices of cassava products. This spurred an expansion of cassava cropping in neighboring countries from 713,000 ha in 2009 to > 1 million ha by 2011: satellite imagery reveals 388%, 330%, 185% and 608% increases in peak deforestation rates in Cambodia, Lao PDR, Myanmar and Vietnam focused in cassava crop expansion areas. Following release of the host-specific parasitoid Anagyrus lopezi (Hymenoptera) in 2010, mealybug outbreaks were reduced, cropping area contracted and deforestation slowed by 31-95% in individual countries. Hence, when judiciously implemented, insect biological control can deliver substantial environmental benefits.

Identifying crop research priorities based on potential economic and poverty reduction impacts: The case of cassava in Africa, Asia, and Latin America.

It is widely recognized that increasing agricultural production to the levels needed to feed an expanding world population requires sharply increased public investment in research and development and widespread adoption of new technologies, but funding for national and international agricultural research has rather declined in recent years. In this situation, priority setting has become increasingly important for allocating scarce research resources among competing needs to achieve greater impacts. Using partial equilibrium economic surplus models and poverty impact simulations, this paper assesses cassava research priorities in Africa, Latin America and Caribbean, and Asia based on the potential economic and poverty reduction impacts of alternative research and technology options. The results showed that efficient planting material production and distribution systems and sustainable crop and soil fertility management practices have the greatest expected economic and poverty reduction impacts in the three regions. Lack of clean planting materials is a major constraint to adoption and it is envisaged that efficient production and distribution systems for planting material can accelerate technology adoption by farmers. Similarly, sustainable crop and soil fertility management practices play a key role in closing the observed yield gaps, especially in Africa. The paper discusses the results of the priority assessment for key cassava research options and concludes with the implications for cassava research priorities.

Cassava flour slurry as a low-cost alternative to commercially available gel for obstetrical ultrasound: a blinded non-inferiority trial comparison of image quality.

OBJECTIVE: To evaluate the quality of ultrasound images obtained with cassava flour slurry (CFS) compared with conventional gel in order to determine objectively whether CFS could be a true low-cost alternative. DESIGN: Blinded non-inferiority trial. SETTING: Obstetrical ultrasound unit in an academic medical centre. POPULATION OR SAMPLE: Women with a singleton pregnancy, undergoing anatomy ultrasounds. METHODS: Thirty pregnant women had standard biometry measures obtained with CFS and conventional gel. Images were compared side-by-side in random order by two blinded sonologists and rated for image resolution, detail and total image quality using a 10-cm visual analogue scale. Ratings were compared using paired t-tests. Participant and sonographer experience was measured using five-point Likert scales. MAIN OUTCOME MEASURES: Image resolution, detail, and total image quality. Participant experience of gel regarding irritation, messiness, and ease of removal. RESULTS: We found no significant difference between perceived image quality obtained with CFS (mean = 6.2, SD = 1.2) and commercial gel (mean = 6.4, SD = 1.2) [t (28) = -1.1; P = 0.3]. Images were not rated significantly differently for either reviewer in any measure, any standardized image or any view of a specific anatomic structure. All five sonographers rated CFS as easy to obtain clear images and easy for patient and machine cleanup. Only one participant reported itching with CFS. CONCLUSIONS: CFS produces comparable image quality to commercial ultrasound gel. The dissemination of these results and the simple CFS recipe could significantly increase access to ultrasound for screening, monitoring and diagnostic purposes in resource-limited settings. FUNDING: This study was internally funded by our department. TWEETABLE ABSTRACT: Low-cost homemade cassava flour slurry creates images equal to commercial ultrasound gel, improving access.

Aspectos econômicos do uso da parte aérea in natura de mandioca (Manihot esculenta Crantz) para nutrição de cordeiros confinados e semiconfinados / Economic aspects of the aerial part of in natura cassava (Manihot esculenta Crantz) for the nutrition of confined and semi-confined lambs

O objetivo deste trabalho foi avaliar a influência da inclusão da rama de mandioca na dieta de cordeiros confinados e semiconfinados, em substituição parcial de alimentos concentrados, como forma de redução de custos de produção. O experimento foi conduzido no Centro de Tecnologia de Ovinos (CTO), município de Campo Grande, MS. Foram utilizados 56 cordeiros do grupo genético Pantaneiro, sendo 28 machos e 28 fêmeas, com pesos médios de 18,84kg±2,02kg. As dietas recebidas foram: tratamento controle com ração comercial e tratamentos contendo a parte aérea de mandioca (PAM) em substituição de 10% dessa ração. Os machos confinados obtiveram ganho de peso médio diário de 210g e os semiconfinados, de 178g. No semiconfinamento, as fêmeas controle tiveram GMD de 120g e menor desempenho entre os grupos experimentais. A inclusão PAM acarretou uma redução de 31,29% para a mesma categoria animal. Entre os sistemas de produção, o semiconfinamento apresentou maior lucratividade média, 6,4%, e uma rentabilidade de 7,99% em relação ao sistema de confinamento, que obteve 0,04% de lucratividade e 0,87% de rentabilidade. Conclui-se que a inclusão da parte aérea da mandioca aumenta a eficiência econômica dos sistemas produtivos sem afetar o desenvolvimento dos animais em terminação.(AU)

The scope of this study was to evaluate the inclusion of raw cassava aerial parts in the diet of lambs in partial substitution of rations, in order to reduce production costs. The experiment was conducted at Sheep Technology Centre (CTO) in Campo Grande City, MS. A sample of 56 lambs from Pantaneiro genetic group was used, 28 males and 28 females, average weight of 18.84kg±2.02kg. The inclusion of PAM decreased the costs by 31.29% for the same category of animal. Among the production systems the semi-feedlot, showed the highest average profitability of 6.4% and a return of 7.99%, compared to the feedlot system, which obtained 0.04% 0.87% profitability and return. In conclusion, the inclusion of the aerial part of cassava increases the economic efficiency of production systems without affecting the development of finishing animals.(AU)

The industrial applications of cassava: current status, opportunities and prospects.

Cassava (Manihot esculenta Crantz) is a drought-tolerant, staple food crop that is grown in tropical and subtropical areas. As an important raw material, cassava is a valuable food source in developing countries and is also extensively employed for producing starch, bioethanol and other bio-based products (e.g. feed, medicine, cosmetics and biopolymers). These cassava-based industries also generate large quantities of wastes/residues rich in organic matter and suspended solids, providing great potential for conversion into value-added products through biorefinery. However, the community of cassava researchers is relatively small and there is very limited information on cassava. Therefore this review summarizes current knowledge on the system biology, economic value, nutritional quality and industrial applications of cassava and its wastes in an attempt to accelerate understanding of the basic biology of cassava. The review also discusses future perspectives with respect to integrating and utilizing cassava information resources for increasing the economic and environmental sustainability of cassava industries. © 2017 Society of Chemical Industry.

Production of raw starch-degrading enzyme by Aspergillus sp. and its use in conversion of inedible wild cassava flour to bioethanol.

The major bottlenecks in achieving competitive bioethanol fuel are the high cost of feedstock, energy and enzymes employed in pretreatment prior to fermentation. Lignocellulosic biomass has been proposed as an alternative feedstock, but because of its complexity, economic viability is yet to be realized. Therefore, research around non-conventional feedstocks and deployment of bioconversion approaches that downsize the cost of energy and enzymes is justified. In this study, a non-conventional feedstock, inedible wild cassava was used for bioethanol production. Bioconversion of raw starch from the wild cassava to bioethanol at low temperature was investigated using both a co-culture of Aspergillus sp. and Saccharomyces cerevisiae, and a monoculture of the later with enzyme preparation from the former. A newly isolated strain of Aspergillus sp. MZA-3 produced raw starch-degrading enzyme which displayed highest activity of 3.3 U/mL towards raw starch from wild cassava at 50°C, pH 5.5. A co-culture of MZA-3 and S. cerevisiae; and a monoculture of S. cerevisiae and MZA-3 enzyme (both supplemented with glucoamylase) resulted into bioethanol yield (percentage of the theoretical yield) of 91 and 95 at efficiency (percentage) of 84 and 96, respectively. Direct bioconversion of raw starch to bioethanol was achieved at 30°C through the co-culture approach. This could be attractive since it may significantly downsize energy expenses.

The retail market for fresh cassava root tubers in the European Union (EU): the case of Copenhagen, Denmark--a chemical food safety issue?

BACKGROUND: A number of retail shops in Copenhagen sell fresh cassava roots. Cassava roots contain the toxic cyanogenic glucoside linamarin. A survey was made of the shop characteristics, origin of the roots, buyers, shop owner's knowledge of toxicity levels, and actual toxicity levels. RESULTS: Shops selling fresh cassava were shown mostly to be owned by persons originating in the Middle East or Afghanistan, buyers were found to predominantly be of African origin, and sellers' knowledge concerning the potential toxicity was found to be very restricted. Seventy-six per cent of the roots purchased had a total cyanogenic potentials (CNp) above the 50 mg HCN equivalents kg(-1) dry weight (d.w.) proposed as acceptable by an EU working group. Two of 25 roots purchased had CNp higher than 340 mg HCN eq. kg(-1) d.w. CONCLUSION: The EU has previously made risk assessments concerning cassava and cyanogenic compounds. In the light of the conclusions drawn, the EU needs to make decisions about how to deal with the regulation and control of fresh cassava roots imported to the European food market. Also cassava root products and cassava leaves should be considered.

Agricultural biotechnology and its contribution to the global knowledge economy.

The theory of neoclassical welfare economics largely shaped international and national agricultural policies during the Cold War period. It treated technology as an exogenous factor that could boost agricultural productivity but not necessarily sustainable agriculture. New growth theory, the economic theory of the new knowledge economy, treats technological change as endogenous and argues that intangible assets such as human capital and knowledge are the drivers of sustainable economic development. In this context, the combined use of agricultural biotechnology and information technology has a great potential, not just to boost economic growth but also to empower people in developing countries and improve the sustainable management of natural resources. This article outlines the major ideas behind new growth theory and explains why agricultural economists and agricultural policy-makers still tend to stick to old welfare economics. Finally, the article uses the case of the Cassava Biotechnology Network (CBN) to illustrate an example of how new growth theory can be applied in the fight against poverty. CBN is a successful interdisciplinary crop research network that makes use of the new knowledge economy to produce new goods that empower the poor and improve the productivity and nutritional quality of cassava. It shows that the potential benefits of agricultural biotechnology go far beyond the already known productivity increases and pesticide use reductions of existing GM crops.