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1.
J Environ Manage ; 325(Pt A): 116590, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36419302

RESUMO

The detrimental effects of pesticides on the environment and human health have motivated the development of alternative pest control strategies. Pheromonal pest control is one alternative strategy that is attractive because most pheromones used commercially are non-toxic. Pheromones are also effective at low concentrations, and insects are slower to develop resistance to them compared to pesticides. Pheromones can be used to control pests by attracting them towards traps, repelling them from crops, or disrupting their mating behaviour. Viability of pheromonal control strategies must be evaluated on a case-by-case basis and depends on the target species, the pheromone being used, the specific control strategy, the method of dispensing pheromone, other pest control strategies pheromones being used alongside, and many other factors. The efficacy of pheromonal control has been demonstrated in commercial applications such as the control of palm weevils using traps releasing their male aggregation pheromone. Mating disruption using female sex pheromones has also been widely applied for control of both the codling moth Cydia Pomonella and the european grapevine moth Lobesia Botrana (Bangels and Beliën, 2012; Lucchi et al., 2018). Pheromones are volatiles that both degrade quickly in the environment and can be rapidly dispersed by wind. Consequently, administering pheromones to fields requires the use of dispensers that emits pheromone continuously or intermittently. Septum dispensers, membrane dispensers and solid matrix dispensers are best suited to treating smaller areas of cropland since they need to be installed by hand, a labor-intensive process. For treating a large area with pheromones, sprayable formulations and aerosol dispensers are alternative dispensing technologies that can be employed. The characteristics of these different dispenser designs are discussed as well as the kinetics governing pheromone release. Possible areas for future work in pheromone dispenser technology include examining new integrated strategies that employ pheromones alongside other pest control techniques in unique ways. The combination of pheromonal control with physical exclusion or predator release are examples of integrated strategies that are promising but have yet to be widely commercialized. Most commercial pheromonal dispensers are also noted to be impossible or impractical to reuse, apart from aerosol devices. Creating new types of rechargeable dispenser might have some cost saving benefits and would be an interesting area for future innovation in this field.


Assuntos
Praguicidas , Gorgulhos , Feminino , Masculino , Humanos , Animais , Feromônios/farmacologia , Produtos Agrícolas , Controle de Pragas
2.
Bioresour Technol ; 362: 127782, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35970500

RESUMO

This study aimed to efficiently convert banana peels (BP) into 5-hydroxymethylfurfural (HMF) by using an integrated mechanoenzymatic/catalytic approach. There is no report on HMF production using mechanoenzymatic hydrolysis. Moreover, this method enables saccharification of lignocellulose without bulk solvents or pretreatment. The effects of the reaction volume, milling time, and reactive aging (RAging) on the mechanoenzymatic hydrolysis of BP were studied. The solvent-free enzymatic hydrolysis of BP under RAging conditions was found to provide higher glucose (40.5 wt%) and fructose (17.2 wt%) yields than chemical hydrolysis. Next, the conversion of the resulting monosaccharides into HMF in the presence of the AlCl3·H2O/HCl-DMSO/H2O system resulted in 71.9 mol% yield, which is so far the highest HMF yield obtained from cellulosic food wastes. Under identical reaction conditions, direct conversion of untreated BP to HMF yielded 22.7 mol% HMF, suggesting that mechanoenzymatic hydrolysis greatly promotes the release of sugars from BP to improve HMF yield.


Assuntos
Musa , Catálise , Furaldeído/análogos & derivados , Hidrólise , Solventes , Açúcares
3.
Appl Microbiol Biotechnol ; 106(11): 4029-4039, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35608668

RESUMO

The use of waste stream residues as feedstock for material production simultaneously helps reduce dependence on fossil-based resources and to shift toward a circular economy. This study explores the conversion of food waste into valuable chemicals, namely, bio-pigments. Here, a simulated food waste feedstock was converted into pigments via solid-state fermentation with the filamentous fungus Talaromyces albobiverticillius (NRRL 2120). Pigments including monascorubrin, rubropunctatin, and 7-(2-hydroxyethyl)-monascorubramine were identified as products of the fermentation via ultra-performance liquid chromatography coupled with quadrupole-time-of-flight electrospray ionization mass spectrometry. Pigments were obtained at concentrations of 32.5, 20.9, and 22.4 AU/gram dry substrate for pigments absorbing at 400, 475, and 500 nm, respectively. Pigment production was further enhanced by co-culturing T. albobiverticillius with Trichoderma reesei (NRRL 3652), and ultimately yielded 63.8, 35.6, and 43.6 AU/gds at the same respective wavelengths. This represents the highest reported production of pigments via solid-state fermentation of a non-supplemented waste stream feedstock. KEY POINTS: • Simulated food waste underwent solid-state fermentation via filamentous fungi. • Bio-pigments were obtained from fermentation of the simulated food waste. • Co-culturing multiple fungal species substantially improved pigment production.


Assuntos
Alimentos , Eliminação de Resíduos , Técnicas de Cocultura , Fermentação , Fungos , Eliminação de Resíduos/métodos
4.
Molecules ; 27(5)2022 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-35268743

RESUMO

Pisum sativum is a leguminous crop suitable for cultivation worldwide. It is used as a forage or dried seed supplement in animal feed and, more recently, as a potential non-traditional oilseed. This study aimed to develop a low-cost, rapid, and non-destructive method for analyzing pea lipids with no chemical modifications that would prove superior to existing destructive solvent extraction methods. Different pea accession seed samples, prepared as either small portions (0.5 mm2) of endosperm or ground pea seed powder for comparison, were subjected to HR-MAS NMR analyses and whole seed samples underwent NIR analyses. The total lipid content ranged between 0.57-3.45% and 1.3-2.6% with NMR and NIR, respectively. Compared to traditional extraction with butanol, hexane-isopropanol, and petroleum ether, correlation coefficients were 0.77 (R2 = 0.60), 0.56 (R2 = 0.47), and 0.78 (R2 = 0.62), respectively. Correlation coefficients for NMR compared to traditional extraction increased to 0.97 (R2 = 0.99) with appropriate correction factors. PLS regression analyses confirmed the application of this technology for rapid lipid content determination, with trends fitting models often close to an R2 of 0.95. A better robust NIR quantification model can be developed by increasing the number of samples with more diversity.


Assuntos
Pisum sativum
5.
Polymers (Basel) ; 14(3)2022 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-35160428

RESUMO

Spent coffee grounds (SCG) are a current subject in many works since coffee is the second most consumed beverage worldwide; however, coffee generates a high amount of waste (SCG) and can cause environmental problems if not discarded properly. Therefore, several studies on SCG valorization have been published, highlighting its waste as a valuable resource for different applications, such as biofuel, energy, biopolymer precursors, and composite production. This review provides an overview of the works using SCG as biopolymer precursors and for polymer composite production. SCG are rich in carbohydrates, lipids, proteins, and minerals. In particular, carbohydrates (polysaccharides) can be extracted and fermented to synthesize lactic acid, succinic acid, or polyhydroxyalkanoate (PHA). On the other hand, it is possible to extract the coffee oil and to synthesize PHA from lipids. Moreover, SCG have been successfully used as a filler for composite production using different polymer matrices. The results show the reasonable mechanical, thermal, and rheological properties of SCG to support their applications, from food packaging to the automotive industry.

6.
Bioresour Technol ; 344(Pt A): 126169, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34695584

RESUMO

The objective of this study was to explore the use of filamentous fungi as oxidative biocatalysts. To that end, filamentous fungal whole-cells, comprising five different species were employed in the oxidation of 5-(hydroxymethyl)furfural (HMF). Two species (A. niger and T. reesei), which demonstrated superior HMF conversion and product accumulation, were further evaluated for growth on alternative substrates (e.g. pentoses) as well as for use in a chemo-biocatalytic reaction system. Concerning the latter, the two whole-cell biocatalysts were coupled with laccase/TEMPO in a one-pot reaction designed to enable catalysis of the three oxidative steps necessary to convert HMF into 2,5-furandicarboxylic acid (FDCA), a compound with immense potential in the production of sustainable and eco-friendly polymers. Ultimately, the optimal one-pot chemo-biocatalytic cascade system, comprising 1 g/L T. reesei whole cells coupled with 2.5 mM laccase and 20 mol% TEMPO, achieved a molar yield of 88% after 80 h.


Assuntos
Ácidos Dicarboxílicos , Furanos , Fungos , Furaldeído/análogos & derivados
7.
Curr Res Food Sci ; 3: 146-157, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32914130

RESUMO

The recovery of gelatins from Atlantic salmon (Salmo salar) skin for film formation and characterization was studied. Fish skins pre-treated with trypsin (250 U/g) produced the highest hydroxyproline content (7.41 ± 0.49 mg hydroxyproline/g treated skin) and yield (53.05 ± 4.38%) of gelatin, as compared to the use of saline solution. Pre-treatment with a lower concentration of trypsin (1 U/g) at a shorter pre-treatment time successfully reduced the degradation of gelatin with co-production of high molecular weight α-chains. Gelatin was further extracted by a trypsin-aided process for film formation and characterization. Films with increasing protein concentration (from 1 to 5%, w/v) exhibited higher thickness, tensile strength, and elongation at break (EAB), but a marked decrease in EAB for films with 6 and 7% (w/v). Films with 5% proteins showed higher thickness, lower tensile strength and higher EAB with increasing concentrations of glycerol (from 10 to 50% of proteins, w/w). All films exhibited high water uptake, decrease in light transmission and an increase in opacity as the protein and glycerol contents increased. Electrophoretic studies showed that the increase in the mechanical properties of the films was correlated with the increase in protein concentration, owing to the increased content of high molecular weight chain fractions. Furthermore, Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) revealed the interaction between the proteins and glycerol for all films. This study demonstrated the viability of the trypsin supplementation process to obtain salmon skin gelatin for film formation.

8.
Molecules ; 24(23)2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31756935

RESUMO

Current enzymatic methods for hemicellulosic biomass depolymerization are solution-based, typically require a harsh chemical pre-treatment of the material and large volumes of water, yet lack in efficiency. In our study, xylanase (E.C. 3.2.1.8) from Thermomyces lanuginosus is used to hydrolyze xylans from different sources. We report an innovative enzymatic process which avoids the use of bulk aqueous, organic or inorganic solvent, and enables hydrolysis of hemicellulose directly from chemically untreated biomass, to low-weight, soluble oligoxylosaccharides in >70% yields.


Assuntos
Biomassa , Endo-1,4-beta-Xilanases/química , Eurotiales/enzimologia , Proteínas Fúngicas/química , Polissacarídeos/química , Água/química , Hidrólise
9.
N Biotechnol ; 49: 161-168, 2019 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-30465907

RESUMO

In emerging bioeconomies, the compostable biopolymers polyhydroxyalkanoates (PHAs) are desirable products due to their similarity to petropolymers. While industrial PHA production has been growing rapidly, obtaining a cheap and sustainable carbon source is still a challenge. Among biobased feedstocks, lignocellulose is a cheap, abundant and potentially sustainable carbon source. However, because of its recalcitrance, separation and depolymerization processes that have not reached industrial maturity are usually required. Integrated biorefineries utilize a holistic approach to conversion processes to minimize feedstock price and maximize resource use. This review examines the technical feasibility of merging PHA production and lignocellulose biorefining in integrated processing facilities. Among lignocellulosic feedstocks, wood is a promising carbon source due to its mature industrial infrastructure. Among the lignocellulose components, the hemicellulose fraction is the most promising feedstock for PHA production since it is underutilized and can be combined with bioethanol production from the cellulose fraction. Fractionation processes allow separate recovery of cellulose, hemicellulose and lignin, to which PHA can be added as a co-product.


Assuntos
Biotecnologia/métodos , Lignina/metabolismo , Poli-Hidroxialcanoatos/biossíntese , Lignina/química , Redes e Vias Metabólicas , Poli-Hidroxialcanoatos/química
10.
Int J Biol Macromol ; 120(Pt A): 263-273, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30130612

RESUMO

Composite films comprised of salmon (Salmo salar) skin gelatin and zein were prepared via crosslinking with glutaraldehyde. Response surface methodology (RSM) was used to optimize film composition to maximize tensile strength (TS) and elongation at break (EAB), and to minimize water solubility (WS) of the films. The significant (P < 0.05) variables affecting film properties were: glutaraldehyde for TS, and zein and glutaraldehyde for both EAB and WS. The optimum concentrations (g/mL) to maximize TS and EAB and to minimize WS were 3% zein and 0.02% glutaraldehyde, which yielded films having a TS of 3.11 ±â€¯0.01 MPa, EAB of 22.43 ±â€¯1.57%, and WS of 38.82 ±â€¯1.71%. The infrared spectra and morphological analyses demonstrated that the gelatin-zein composite film was successfully crosslinked after the addition of glutaraldehyde, with the formation of crosslinked networks between proteins and a denser packed organization of proteins. Consequently, the resultant crosslinked composite film exhibited improvement on light transparency, water resistance and mechanical strength as a function of increasing humidity.


Assuntos
Reagentes de Ligações Cruzadas/química , Gelatina/química , Glutaral/química , Membranas Artificiais , Salmo salar , Pele/química , Zea mays/química , Zeína/química , Animais , Resistência à Tração
11.
Biomacromolecules ; 19(1): 188-200, 2018 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-29182307

RESUMO

Softwood hemicellulose hydrolysates are a cheap source of sugars that can be used as a feedstock to produce polyhydroxybutyrates (PHB), which are biobased and compostable bacterial polyesters. To assess the potential of the hemicellulosic sugars as a carbon source for PHB production, synthetic media containing softwood hemicellulose sugars (glucose, mannose, galactose, xylose, arabinose) and the potentially inhibitory lignocellulose degradation products (acetic acid, 5-hydroxymethylfurfural (HMF), furfural, and vanillin) were fermented with the model strain Paraburkholderia sacchari IPT 101. Relative to pure glucose, individual fermentation for 24 h with 20 g/L mannose or galactose exhibited maximum specific growth rates of 97% and 60%, respectively. On the other hand, with sugar mixtures of glucose, mannose, galactose, xylose, and arabinose, the strain converted all sugars simultaneously to reach a maximum PHB concentration of 5.72 g/L and 80.5% PHB after 51 h. The addition of the inhibitor mixture at the following concentration, sodium acetate (2.11 g/L), HMF (0.67 g/L), furfural (0.66 g/L), and vanillin (0.93 g/L), to the sugar mixture stopped the growth entirely within 24 h. Individually, the inhibitors either had no effect or only reduced growth. Moreover, it was found that a bacterial inoculum with high initial cell density (optical density, OD ≥ 5.6) could overcome the growth inhibition to yield an OD of 13 within 24 h. Therefore, softwood hemicellulose sugars are viable carbon sources for PHB production. Nevertheless, real softwood hemicellulose hydrolysates need detoxification or a high inoculum to overcome inhibitory effects and allow bacterial growth.


Assuntos
Burkholderiales/metabolismo , Butiratos/metabolismo , Carbono/metabolismo , Modelos Biológicos , Polissacarídeos/metabolismo , Madeira/metabolismo , Fermentação , Hidrólise
12.
J Food Sci Technol ; 54(12): 4000-4008, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29085142

RESUMO

Gelatin from salmon (Salmo salar) skin with high molecular weight protein chains (α-chains) was extracted using trypsin-aided process. Response surface methodology was used to optimise the extraction parameters. Yield, hydroxyproline content and protein electrophoretic profile via sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of gelatin were used as responses in the optimization study. The optimum conditions were determined as: trypsin concentration at 1.49 U/g; extraction temperature at 45 °C; and extraction time at 6 h 16 min. This response surface optimized model was significant and produced an experimental value (202.04 ± 8.64%) in good agreement with the predicted value (204.19%). Twofold higher yields of gelatin with high molecular weight protein chains were achieved in the optimized process with trypsin treatment when compared to the process without trypsin.

13.
Ultrason Sonochem ; 27: 1-9, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26186814

RESUMO

The use of ultrasonic processing was evaluated for its ability to achieve adequate mixing while providing sufficient activation energy for the enzymatic transesterification of waste tallow. The effects of ultrasonic parameters (amplitude, cycle and pulse) and major reaction factors (molar ratio and enzyme concentration) on the reaction kinetics of biodiesel generation from waste tallow bio-catalyzed by immobilized lipase [Candida antarctica lipase B (CALB)] were investigated. Three sets of experiments namely A, B, and C were conducted. In experiment set A, two factors (ultrasonic amplitude and cycle) were investigated at three levels; in experiment set B, two factors (molar ratio and enzyme concentration) were examined at three levels; and in experiment set C, two factors (ultrasonic amplitude and reaction time) were investigated at five levels. A Ping Pong Bi Bi kinetic model approach was employed to study the effect of ultrasonic amplitude on the enzymatic transesterification. Kinetic constants of transesterification reaction were determined at different ultrasonic amplitudes (30%, 35%, 40%, 45%, and 50%) and enzyme concentrations (4, 6, and 8 wt.% of fat) at constant molar ratio (fat:methanol); 1:6, and ultrasonic cycle; 5 Hz. Optimal conditions for ultrasound-assisted biodiesel production from waste tallow were fat:methanol molar ratio, 1:4; catalyst level 6% (w/w of fat); reaction time, 20 min (30 times less than conventional batch processes); ultrasonic amplitude 40% at 5 Hz. The kinetic model results revealed interesting features of ultrasound assisted enzyme-catalyzed transesterification (as compared to conventional system): at ultrasonic amplitude 40%, the reaction activities within the system seemed to be steady after 20 min which means the reaction could proceed with or without ultrasonic mixing. Reversed phase high performance liquid chromatography indicated the biodiesel yield to be 85.6±0.08%.


Assuntos
Biocatálise , Biocombustíveis , Gorduras/química , Proteínas Fúngicas/metabolismo , Lipase/metabolismo , Sonicação , Esterificação , Cinética , Metanol/química , Modelos Químicos
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