Agro-industrial Residues Research Articles

Use of wood bottom ash in cementitious materials: a review

The search for sustainable solutions associated with cement production has drawn increasingly attention. Concurrently, agro-industrial residues are being generated more frequently and do not have an environmentally appropriate destination. Thus, one option is to use these agro-industrial residues as supplementary cementitious materials. Among these residues, wood ash generated in thermoelectric plants or in small industrial furnaces stands out. This study presents a comprehensive review on the use of wood bottom ash (WBA) in cementitious materials, addressing its characterization, microstructure, mechanical performance, durability and environmental aspects. It is concluded that there is an optimal range of values for replacing cement by WBA between 5 and 20%. The chemical characteristics are different, with a relatively higher amount of Ca and Si. The sum of iron + aluminum + silicon oxides is generally less than 70% and the loss on ignition greater than 9%. The pozzolanicity is zero or low, but depends on the presence of the amorphous phase and the surface area. The morphology is irregular, impairing the workability, and can be improved with additives. In general, processing is necessary to adjust the properties, mainly granulometry and reactivity. The setting times were divergent. Mechanical properties were impaired and porosity increased, which negatively impacts durability characteristics. The environmental assessment of the WBA cementitious product indicated it as not harmful. Considering that there might be harmful effects in the use of ash in concrete, the material should be better studied, in addition to evaluating its use in non-structural concrete and mortars that do not require high mechanical resistance.

Carposome productivity of Pleurotus ostreatus and Pleurotus eryngii growing on agro-industrial residues enriched with nitrogen, calcium salts and oils

The suitability of the abundant agro-industrial residues wheat straw (WS; control), barley and oats straw (BOS) and rice husk (RH), supplemented with various sources of oils (sunflower, corn oil), nitrogen (peptone, yeast extract) and calcium salts (CaSO4·2H2O, CaCl2), as novel substrates in solid-state fermentation of selected Pleurotus ostreatus and P. eryngii mushrooms was investigated. The possible effect of different additives on mycelial growth rate, biomass production and endoglucanase, laccase and lipase biosynthesis were evaluated. Moreover, their impact on essential cultivation aspects (earliness, total mushroom yield, biological efficiency) and carposome quality parameters (weight, morphological characteristics) was assessed. Both fungi showed their highest growth rates on BOS substrates and the most positive implementation was CaSO4·2H2O 6 % w/w (Kr = 9.58 mm/ day; P. ostreatus, Kr = 9.42 mm/ day; P. eryngii), while different additives led to enhancement of biomass production. Pleurotus species demonstrated minimal levels of endoglucanase activity, with values ranging from 0.01 to 0.42 U/g of dry weight, regardless of the substrate and the stage of colonization. On the contrary, the maximum values of laccase activity were observed at 50 % of colonization on BOS and RH, while supplementation with nitrogen and calcium sources positively affected its biosynthesis. P. ostreatus and P. eryngii cultivated on BOS supplemented with peptone at 2 and 5 % w/w, synthesized significant laccase amounts, i.e., 12,165.78 and 8,624.55 U/g d.w., respectively. Satisfactory amounts of lipase were produced, especially in substrates supplemented with sunflower 2 % w/w, in quantities up to 1.42 U/g d.w., whereas the highest lipase activity was achieved by P. eryngii on WS supplemented with corn oil at 2 % w/w, with a value of 4.25 U/g d.w. being recorded. Regarding fermentation of Pleurotus species in polypropylene bags, WS and BOS supported faster colonization and shorter earliness period than RH substrates, whereas supplementation did not seem to affect these culture parameters. Furthermore, oils supplementation had a positive effect on BE of both species, with values up to 100 % for P. ostreatus and 80 % for P. eryngii on WS and BOS, whereas on RH the lowest BE values were detected. Morphological characteristics were not significantly affected by the additives. Results indicate the positive impact that certain additives have on mushroom productivity and production of enzymes with great financial and environmental importance.

Cellulose-Based Scaffolds: A Comparative Study for Potential Application in Articular Cartilage.

Osteoarthritis is a highly prevalent disease worldwide that leads to cartilage loss. Tissue engineering, involving scaffolds, cells, and stimuli, has shown to be a promising strategy for its repair. Thus, this study aims to manufacture and characterise different scaffolds with poly(ε-caprolactone) (PCL) with commercial cellulose (microcrystalline (McC) and methyl cellulose (MC) or cellulose from agro-industrial residues (corncob (CcC)) and at different percentages, 1%, 2%, and 3%. PCL scaffolds were used as a control. Morphologically, the produced scaffolds presented porosities within the desired for cell incorporation (57% to 65%). When submitted to mechanical tests, the incorporation of cellulose affects the compression resistance of the majority of scaffolds. Regarding tensile strength, McC2% showed the highest values. It was proven that all manufactured scaffolds suffered degradation after 7 days of testing because of enzymatic reactions. This degradation may be due to the dissolution of PCL in the organic solvent. Biological tests revealed that PCL, CcC1%, and McC3% are the best materials to combine with human dental pulp stem/stromal cells. Overall, results suggest that cellulose incorporation in PCL scaffolds promotes cellular adhesion/proliferation. Methyl cellulose scaffolds demonstrated some advantageous compressive properties (closer to native cartilaginous tissue) to proceed to further studies for application in cartilage repair.

Addition of glycerol to agroindustrial residues of bioethanol for fuel-flexible agropellets: Fundamental fuel properties, combustion, and potential slagging and fouling from residual ash

Addition of glycerol to agroindustrial residues of bioethanol for fuel-flexible agropellets: Fundamental fuel properties, combustion, and potential slagging and fouling from residual ash

PRODUCTION OF LACCASE FROM GANODERMA SP. BY USING AGRO-RESIDUAL WASTES

Solid-state fermentation (SSF) has emerged as a potential technology for the production of microbial products such asfeed, fuel, food, industrial chemicals and pharmaceutical products. Its application in bioprocesses such as bioleaching, biobeneficiation, bioremediation, biopulping, etc. has offered several advantages. Utilisation of agro-industrial residues assubstrates in SSF processes provides an alternative avenue and value-addition to these otherwise under- or non-utilisedresidues. The aim of this study was to determine the most promising fungus, the best solid substrate and the optimalconditions for the production of laccase. A laccase producing fungus Ganoderma sp. was isolated and produces laccase byutilizing the agro-wastes. The study revealed that the rice bran was found to be the best supported lignocellulosicsubstrate for extracellular laccase production under SSF and optimum condition for highest lacacse activity of pH andtemperature were observed at 6.0 and 45°C respectively. The incubation periods for laccase maximum activity was at 8thday. Glucose and Peptone were the best supported carbon and nitrogen source for the maximum laccase activity.

Fruit and Restaurant Waste Polysaccharides Recycling Producing Xylooligosaccharides

A significant part of fruit production is wasted annually, a material of high value without use, causing environmental and social damage. These residues from agro-industrial processes, or those that can no longer be used in the market, can be recycled and generate value-added products by pretreatments/hydrolysis. One of the important pretreatments is acid hydrolysis, which can produce xylooligosaccharides (XOS) from biomass, a product of great commercial value in the food and pharmaceutical markets, mainly due to its prebiotic potential. Bananas, oranges, and guava generate a large volume of waste and represent much of Brazil’s fruit production. The dilute acid hydrolysis resulted in XOS production of 37.69% for banana peel, 59.60% for guava bagasse, 28.70% for orange bagasse, and 49.64% for restaurant residue. XOS were quantified by a liquid chromatograph system with a Bio-Rad Aminex HPX-87C column. The results show that, for this type of material and hydrolysis, the ideal conditions to produce XOS are high temperature, low time, and high acid concentration for banana peel residue (160 °C, 15 min, and 3% H2SO4), low temperature, low time, and high acid concentration for guava bagasse (100 °C,15 min and 3% H2SO4), high temperature and acid concentration with low time for orange bagasse (160 °C,15 min and 3% H2SO4) and high temperature and time and high acid concentration for restaurant waste (160 °C, 55 min and 3% H2SO4). This study identified acid hydrolysis conditions that maximized XOS production with a low amount of xylose production using agro-industrial and food residues, also showing the high potential of the chosen residues through the high yields of XOS production.

Pleurotus ostreatus Grown on Agro-Industrial Residues: Studies on Microbial Contamination and Shelf-Life Prediction under Different Packaging Types and Storage Temperatures.

The short shelf-life of mushrooms, due to water loss and microbial spoilage, is the main constraint for commercialization and consumption. The effect of substrate type combined with different temperatures and packaging conditions on the shelf-life of fresh Pleurotus ostreatus is scantily researched. The current study investigated the shelf-life of fresh oyster mushrooms grown on low (0.3, 0.3, 0.17) and high (0.7, 0.7, 0.33) rates of olive pruning residues (OLPR), spent coffee grounds (SCG), and both combined residues (OLPR/SCG) with wheat straw (WS), respectively, at ambient (20 °C) and 4 °C temperatures under no packaging, polyethylene plastic bag packaging (PBP), and polypropylene vacuum bag packaging (VBP). Results showed that at ambient temperature OLPR/SCG mushrooms PBP-bagged had an increased shelf-life by 0.5-1.2 days in comparison with WS ones. The predictive models adopted to optimize mushroom shelf-life at ambient temperature set rates of 0.289 and 0.303 of OLPR and OLPR/SCG, respectively, and PBP as the most suitable conditions (9.18 and 9.14 days, respectively). At 4 °C, OLPR/SCG mushrooms VBP-bagged had a longer shelf-life of 2.6-4.4 days compared to WS ones. Predictive models noted a maximized shelf-life of VBP-bagged mushrooms (26.26 days) when a rate of 0.22 OLPR/SCG is incorporated into the initial substrate. The combination of OLPR and SCG increased the shelf-life of fresh Pleurotus ostreatus by decreasing the total microbial count (TMC) while delaying weight loss and veil opening, and maintaining carbohydrate content, good firmness, and considerable protein, in comparison with WS regardless the storage temperature and packaging type.

Production of rhamnolipid biosurfactants in solid-state fermentation: process optimization and characterization studies

BackgroundRhamnolipids are a group of the extracellular microbial surface-active molecules produced by certain Pseudomonas species with various environmental and industrial applications. The goal of the present research was to identify and optimize key process parameters for Pseudomonas aeruginosa PTCC 1074s synthesis of rhamnolipids utilizing soybean meal in solid state fermentation. A fractional factorial design was used to screen the key nutritional and environmental parameters to achieve the high rhamnolipid production. Response surface methodology was used to optimize the levels of four significant factors.ResultsThe characterization of biosurfactant by TLC, FT-IR and H-NMR showed the rhamnolipids presence. In the optimum conditions (temperature 34.5 °C, humidity 80%, inoculum size 1.4 mL, and glycerol 5%), the experimental value of rhamnolipid production was 19.68 g/kg dry substrate. The obtained rhamnolipid biosurfactant decreased water's surface tension from 71.8 ± 0.4 to 32.2 ± 0.2 mN/m with a critical micelle concentration of nearly 70 mg/L. Additionally, analysis of the emulsification activity revealed that the generated biosurfactant was stable throughout a broad pH, temperature, and NaCl concentration range.ConclusionsThe current study confirmed the considerable potential of agro-industrial residues in the production of rhamnolipid and enhanced the production yield by screening and optimizing the significant process parameters.

Enhancing Biobased Volatile Fatty Acids Production from Olive Mill Solid Waste by Optimization of pH and Substrate to Inoculum Ratio

The pH and substrate-to-inoculum ratio (S/I) are important parameters in the anaerobic fermentation of agroindustrial residues, and therefore the optimization of these two parameters is needed for a stable, efficient, and sustainable reactor operation. In this work, the parameters pH (5–9) and S/I (0.5–3 gVS gVS−1) were optimized to produce biobased volatile fatty acids (VFAs) from hydrothermally pretreated olive mill solid waste (HPOMSW). The response variables evaluated in the Doehlert design were total VFAs concentration (tVFAs) (mg L−1) and amounts (%) of isobutyric, butyric, isovaleric, and valeric acids on the VFAs profile. The pH was the variable that most influenced the mixed culture fermentation of HPOMSW, proving to be a key parameter in the process. Microbial community analyses of conditions 1 (S/I = 3 gVS gVS−1 and pH = 7) and 4 (S/I = 1.13 gVS gVS−1 and pH = 5) showed that Proteobacteria and Firmicutes accounted for more than 87% of the total microorganisms identified for both conditions. In addition, the second-order model best fitted the experimental data for the VFAs production at the desirable condition (S/I = 3 gVS gVS−1 and pH = 8).

A Novel Sphingomonas sp. Isolated from Argan Soil for the Polyhydroxybutyrate Production from Argan Seeds Waste.

Polyhydroxybutyrate (PHB) is a biodegradable bio-based polymer synthesized by microorganisms under unfavorable conditions from agro-industrial residues as a source of carbon. These aspects make the bio-based polymer attractive for the mass production of biodegradable plastics, and a definitive replacement for petroleum-based plastics. The aim of this work was to characterize the putative PHB-producing bacterium 1B isolated from the argan soil, to identify the polymer produced, and quantify the PHB production using argan seeds waste. DNA extraction, PCR, and Sanger sequencing were conducted for the molecular identification of strain 1B; the residual biomass and the PHB quantification were measured and compared in the presence of simple sugars and pretreated argan seeds waste. The 1B growth and PHB synthesis were optimized by selecting physical and nutritional parameters: temperature, incubation time, pH, NaCl concentration, and nitrogen sources concentrations. A preliminary characterization of the bio-based polymer extracted was conducted by UV-Visible spectrophotometry and FTIR analysis. The strain 1B was identified as belonging to the genus Sphingomonas. The PHB final yield was higher in a growth culture enriched with argan waste (3.06%) than with simple sugars. The selected conditions for the bacterial optimal growth incremented the PHB final yield to 6.13%, while the increase in the argan residue concentration from 1 to 3% in a larger culture volume led to the PHB final yield of 8.16%. UV-Visible spectrophotometry of the extracted sample reported a remarkable peak at 248 nm, as well as FTIR spectra analysis, showed peaks at 1728 and 1282 wavenumber/cm. Both preliminary characterizations demonstrated that the extracted sample is the bio-based polymer polyhydroxybutyrate. The results reported in this work reveal how the costless available argan seeds can be used for polyhydroxybutyrate production using a novel Sphingomonas species.

Valorization of rice straw, sugarcane bagasse and sweet sorghum bagasse for the production of bioethanol and phenylacetylcarbinol

Open burning of agricultural residues causes numerous complications including particulate matter pollution in the air, soil degradation, global warming and many more. Since they possess bio-conversion potential, agro-industrial residues including sugarcane bagasse (SCB), rice straw (RS), corncob (CC) and sweet sorghum bagasse (SSB) were chosen for the study. Yeast strains, Candida tropicalis, C. shehatae, Saccharomyces cerevisiae, and Kluyveromyces marxianus var. marxianus were compared for their production potential of bioethanol and phenylacetylcarbinol (PAC), an intermediate in the manufacture of crucial pharmaceuticals, namely, ephedrine, and pseudoephedrine. Among the substrates and yeasts evaluated, RS cultivated with C. tropicalis produced significantly (p ≤ 0.05) higher ethanol concentration at 15.3 g L−1 after 24 h cultivation. The product per substrate yield (Yeth/s) was 0.38 g g-1 with the volumetric productivity (Qp) of 0.64 g L−1 h−1 and fermentation efficiency of 73.6% based on a theoretical yield of 0.51 g ethanol/g glucose. C. tropicalis grown in RS medium produced 0.303 U mL−1 pyruvate decarboxylase (PDC), a key enzyme that catalyzes the production of PAC, with a specific activity of 0.400 U mg−1 protein after 24 h cultivation. This present study also compared the whole cells biomass of C. tropicalis with its partially purified PDC preparation for PAC biotransformation. The whole cells C. tropicalis PDC at 1.29 U mL−1 produced an overall concentration of 62.3 mM PAC, which was 68.4% higher when compared to partially purified enzyme preparation. The results suggest that the valorization of lignocellulosic residues into bioethanol and PAC will not only aid in mitigating the environmental challenge posed by their surroundings but also has the potential to improve the bioeconomy.

Efficient removal of sertraline hydrochloride from wastewater using banana peels functionalized: performance adsorption, mechanisms and applicability

ABSTRACT The presence of sertraline hydrochloride (SER) has been detected in water bodies and wastewater, which encourages the search for alternative treatments for its control and removal. Agro-industrial residues are considered efficient adsorbents and functionalization with magnetic nanoparticles improve the adsorptive properties of these materials, in addition to facilitating their separation from a fluid by an external magnetic field. Thus, this study developed and characterized a new material via the functionalization of the banana peel with iron oxide nanoparticles (BANFunc) for the adsorption of SER in batch experiments. Physicochemical and spectroscopic techniques indicated that the BANFunc functionalization method was effective and improved the adsorption capacity (0.68 and 39.96 mg g−1 for BANPure and BANFunc, respectively). The adsorption studies revealed a maximum adsorptive capacity of 142.85 mg g−1 at 240 min and 318 K. Furthermore, the process presented spontaneous and endothermic behaviour, with a better fit to the pseudo-first-order and Langmuir models for the kinetic and isothermal, respectively. The reuse of the biosorbent was effective for five cycles, and even in the 3rd cycle, the adsorbent showed more than 80% SER removal. The adsorption process can be explained by hydrogen bonds and π-interactions. In the synthetic mixture treatment, the biosorbent demonstrated a satisfactory removal rate, of 86.91%, and individual removals of 83.23%, 89.36% and 88.15% for SER, safranine orange and chloroquine, respectively. Therefore, BANFunc is a promising material for large-scale applications, considering its sustainable character and high treatment efficiency.

Sepedonium sp. and Phellinus sp. Novel Isolates: Growth Pattern and Production of Polysaccharide-Protein Complexes on Conventional and Grape Pomace Substrates

PurposeThe growth behavior of novel fungal isolates along with the production of bioactive compounds from mycelia mass during submerged fermentations were investigated using conventional synthetic media and agro-industrial residues as fermentation substrates.MethodsFour novel isolated fungi, belonging to edible or medicinal species, were evaluated for their ex-situ growth on potato dextrose agar. Specific attention was designated to Sepedonium sp. and Phellinus sp. considering their high growth rate in solid state fermentations. Submerged fermentations were subsequently employed using synthetic carbon sources (glucose, fructose and lactose) to assess the fermentation behavior. Following the better growth pattern on glucose and fructose, compared to lactose, grape pomace extract (GPE) was applied as nutrient feedstock to assess the production of biomass and bioactive compounds. Aqueous extraction was performed to obtain crude intracellular polysaccharides (IPS), that were subsequently characterized in terms of antioxidant activity, protein and polysaccharide content.ResultsSepedonium sp. demonstrated the highest biomass production; 11.4 and 10.5 g/L, using glucose and fructose, respectively, whereas Phellinus yielded up to 3.8 g/L. Lactose was also assimilated by both fungal strains, however biomass production was lower. Utilization of GPE affected biomass production; Sepedonium sp. biomass decreased, whereas biomass obtained from Phellinus sp. was enhanced, compared to synthetic sugars. Crude IPS extracts elicit high antioxidant activity (> 75% inhibition of DPPH• free radical).ConclusionThe successful application of conventional and renewable substrates for Sepedonium and Phellinus fermentation was demonstrated, while the mycelia mass derived polysaccharide-protein complexes exhibited bioactive properties, and thus might be utilized as functional food components.Graphical

Identification of Secondary Metabolites of Interest in Pleurotus djamor Using Agave tequilana Bagasse

Agro-industrial residues represent more than 60% of organic wastes worldwide, which could be used to generate other by-products or to be incorporated into other production chains. For example, bagasse is a waste from the tequila industry in Mexico that could be implemented for mushroom cultivation. Additionally, the substrate influences the growth, development, and production of secondary metabolites of fungi. This work presents a comparative experiment that studies the metabolite production in Pleurotus djamor mushrooms on agave bagasse and barley straw (traditional substrate). The biological efficiency (BE), yield, phenolics and flavonoids, antioxidant capacity, tannins, and the identification of low molecular weight metabolites were evaluated. Five treatments were proposed according to the following mixtures of agave bagasse: barley straw: T1 (1:0), T2 (3:1), T3 (1:1), T4 (1:3), and T5 (0:1). T2 had the highest yield (13.39 ± 3.23%), BE (56.7 ± 13.71%), and flavonoids (44.25 mg rutin equivalent (RE)/g); T3 obtained the highest phenol content (230.27 mg GAE/g); and T1 the highest tannins content (0.23 mg (+) catechin equivalent (CE)/g). Finally, T1 and T5 are the ones that present the greatest number of primary metabolites, including hydroxycitric acid, 2-deoxy-D-galactose, D-mannose, paromomycin, palmitic acid, pyrrole, mannitol, and DL arabinose, while in T2, T3, and T4 only two chemical compounds were found present (palmitic acid and pyrrole in T2, silicic acid and pyrrole in T3 and 2-deoxy-D-galactose and quinoline in T4). The cultivation substrate influences the concentration of bioactive molecules in the fruiting bodies of P. djamor. Additionally, P. djamor's degradation of agave bagasse residue generates a potential application for agro-industrial residue management at a low cost.

Utilization of functional agro-waste residues for oyster mushroom production: Nutritions and active ingredients in healthcare.

A large amount of agro-industrial residues are produced from the planting, production and processing of traditional Chinese herbs. As a tonic, edible, and economical herb, Codonopsis pilosula root has been extensively developed into medicine and functional food. However, thousands of tons of aerial parts (stems, leaves, flowers and fruits) have been directly discarded after harvest each year. To utilise agro-wastes, Pleurotus ostreatus was cultivated on a basal substrate supplemented with C. pilosula stems and leaves (CSL). Physicochemical analyses revealed that the basal substrate mixed with CSL was more abundant in cellulose, hemicellulose, and most of micronutrients such as K, Ca, Mg, S, Fe, Zn and Mo. After the first flush, the fruit bodies in CSL group exhibited a higher fresh weight, a wider average pileus diameter and a lower moisture level. Nutrition analyses presented a higher protein content and a lower fat content in mushrooms from CSL group compared with control group. Interestingly, 14 amino acids (glutamine, arginine, valine, leucine, and etc.) and 3 micronutrients (Se, Fe and Zn) were increased after CSL addition to the substrate. Based on untargeted metabolomics, a total of 710 metabolites were annotated. Compared with control group, there were 142 and 117 metabolites significantly increased and decreased in the CSL group. Most of them were grouped into classes of amino acids and peptids, fatty acids, carbohydrates, terpenoids, and etc. Moreover, an abundance of phytometabolites from Codonopsis were detected in P. ostreatus from CSL group, including polyacetylenes or polyenes, flavonoids, alkaloids, terpenoids, organic acids, and etc. UPLC-MS/MS results demonstrated that lobetyolin content in the CSL group samples was 0.0058%. In summary, the aerial parts of C. pilosula processed for use in the production of edible mushroom is an emerging strategy to converting agricultural waste into functional foods.

Agro-industrial residues in the control of gastrointestinal nematodes of small ruminants and fertilization of forages

ABSTRACT: Verminosis in small ruminants can render rural activity impractical, which is still controlled through the administration of anthelmintics. The present study evaluated four agro-industrial residues as fertilizer in the control of GIN of small ruminants in the free-living stage. Crab shell, manipueira, biochar, and organomineral residues were used in pots (5.0 kg of soil) and cultivated with Massai grass (Megathyrsus maximum cv. Massai). Further, the pots were contaminated with feces from sheep carrying a natural multispecific infection by GIN. Next, the residues were applied individually to the soil, with 50 mL/pot for liquid and 50 g/pot for solid residues. Treatment with manipueira showed the lowest number of L3.kg MS-1 recovered from the grass (202.44), when compared with treatments using organomineral (823.89) and biochar (689.34). However, there was no statistically significant difference (P < 0.05) between the four treatments as compared to the control group. These agro-industrial residues can be used as organic fertilizers; however, these will not help in the control of GIN in sheep.

Morphological aspects of rumen papillae of lambs fed agro-industrial wastes.

Sheep meet production systems require roughage feed of good nutritional quality. However, the production of sorghum or corn silage, besides expensive, also depends on large cultivable areas and favorable weather conditions. Thus, agro-industrial residues have stood out as a feed alternative that contribute to the reduction of production costs and to the conservation of the environment. Fragments of the ruminal mucosa of 30 healthy lambs fed with agro-industrial residues and slaughtered with a final weight of 36 kg were analyzed by light and scanning electron microscopy. We observed that the coproducts grape residue and wet brewery residue affected the shape, dimensions, and cytoarchitecture of the rumen epithelium in contrast to traditional sorghum silage. The rumen papillae of lambs fed grape waste were larger, and their epithelium was thinner when compared to the papillae of lambs fed wet brewery waste and sorghum silage. It can be assumed that the increased mucosal surface area of the rumen contributed to greater weight gain and reduced time to slaughter. The use of a greater variety of agro-industrial residues as a substitute for traditional feedstuffs contributes to the increase in animal protein production in many countries, making the confinement of sheep more viable and sustainable.

Vitreous Foam with Thermal Insulating Property Produced with the Addition of Waste Glass Powder and Rice Husk Ash

Closed pore glass foams with dimensions of 60mm × 20 mm × 20 mm were produced using agro-industrial residues. Samples containing sodo-calcic glass powder (78%wt) and rice husk ash (16%wt) were characterized, and their technological properties were investigated. The samples were synthesized in a conventional muffle furnace at 750–800–850 °C. The results presented for apparent density (0.24–0.29 g/cm3), compressive strength (1.5–2.3 MPa) and thermal conductivity (0.021–0.025 W/mK) meet the standards for commercial foam glasses. Low viscosity was achieved at all temperatures as a result of the addition of rice husk ash to the cell structure. X-ray fluorescence showed that the glass was silico-sodo-calcic type (SiO2, Na2O and CaO), and that the rice husk ash was rich in SiO2 (as well as CaO, Na2O, Al2O3, K2O and Fe2O3). The mechanical strength and low thermal conduction of the material showed a good efficiency for use in civil construction as a thermal insulating material. Material made in this way has a lower production cost, and additionally transforms waste into co-products, generating added value, favoring consecutive circulation, as well as a clean and circular economy.

Phytochemicals Derived from Agricultural Residues and Their Valuable Properties and Applications.

Billions of tons of agro-industrial residues are produced worldwide. This is associated with the risk of pollution as well as management and economic problems. Simultaneously, non-edible portions of many crops are rich in bioactive compounds with valuable properties. For this reason, developing various methods for utilizing agro-industrial residues as a source of high-value by-products is very important. The main objective of the paper is a review of the newest studies on biologically active compounds included in non-edible parts of crops with the highest amount of waste generated annually in the world. The review also provides the newest data on the chemical and biological properties, as well as the potential application of phytochemicals from such waste. The review shows that, in 2020, there were above 6 billion tonnes of residues only from the most popular crops. The greatest amount is generated during sugar, oil, and flour production. All described residues contain valuable phytochemicals that exhibit antioxidant, antimicrobial and very often anti-cancer activity. Many studies show interesting applications, mainly in pharmaceuticals and food production, but also in agriculture and wastewater remediation, as well as metal and steel industries.

Desenvolvimento de doce de paçoca de amêndoa de pequi

ABSTRACT: The pequi has an almond with interesting chemical characteristics, such as considerable proportions of proteins and lipids that can be applied in several products aiming to use this agro-industrial residue. This research tookadvantage of the almond for the development of sweet paçoca with different concentrations of pequi almond, containing 0% (PA), 25% (P1), 50% (P2), 75% (P3), and 100% (P4) in place of peanuts. The paçocas were evaluated for proximate parameters and water activity, mineral content, color parameters, microbiological characteristics, and texture profile. The results for aw ranged from 0.48 to 0.52. In the proximate composition, it was observed that with the increase of the almond flour there was a difference in the ash, moisture, and protein contents. Due to the almond roasting process, the paçocas of pequi presented the darkest color. Pequi almond paçocas showed better protein value than peanut paçoca and higher levels of P and Mg. In addition, they present better elasticity, chewability, and cohesiveness.