RESUMO

Biowaste from slaughterhouses can be recovered to benefit food security and reduce contamination potential. More than 3 billion heads of livestock are consumed worldwide, which will increase by 17% by 2028, generating more biowaste, increasing infectious agents, and causing economic losses due to circular economy principles not being applied. This work evaluated the nutritional quality of four types of biowaste from bovine slaughter which were transformed into a meal for guinea pigs (rumen content (RCM), ears (EaM), blood (BM), and cheeks (CM)) according to their chemical composition, digestible components, energy contribution, and voluntary consumption. For the animal model, adult male guinea pigs were arranged in metabolic cages for feces collection without urinary contamination. Nine guinea pigs were used in each digestibility test. First, a direct digestibility test was conducted using a meal of barley as a reference diet (RD), the indigestibility coefficient of which allowed for the estimation of the digestibility of biowaste meals through indirect calculations; for this, diets composed of 80% of the RD and 20% of the corresponding biowaste meals were evaluated. The difference method was suitable for determining the digestibility of beef biowaste using the indigestibility coefficients of the reference diet to calculate the digestibility of ingredients which could not be offered as 100% of the meal but were incorporated as 20%. The digestible protein and metabolizable energy contents of RCM, EaM, BM, and CM were 10.2% and 2853 kcal/kg, 44.5% and 3325 kcal/kg, 70.7% and 2583 kcal/kg, and 80.8% and 3386 kcal/kg, respectively. The CM and BM feeds had the highest contributions of digestible protein due to their higher nitrogen content, and the CM and EaM feeds had the highest ME contents due to their higher fat contents. The biowaste meal consumption in descending order was CM > RCM > EaM > BM, which were consumed without problems. These results are indicative that these components can be part of guinea pigs' diets, and it is recommended to continue studies into guinea pig growth and fattening diets with different levels of these biowaste meals.

RESUMO

Composting is one of the most widely applied methods for recycling organic waste. This process has been proposed as one option that facilitates the reincorporation of materials into the production cycle. However, composting also generates environmental impacts. Life Cycle Assessment (LCA) is the most common approach to evaluate the environmental impacts of a process at different system stages. Nevertheless, applying LCA in composting facilities is challenging due to the extensive information required, the lack of standardization on the initial assumptions, the definition of system boundaries, and the high diversity of existing composting technologies. This paper systematically reviews LCA studies in biowaste and/or green waste composting. The study highlights the challenges that should be met in order to improving the application of LCA to evaluate the environmental impacts of this type or waste treatment strategy. The review protocol used identified 456 papers published between 2010 and 2022. After the screening, 56 papers were selected, read, and thoroughly analyzed. The results show that: i) about 68% of the studies aimed to compare composting with other solid waste management options; ii) there was a wide diversity among the impact categories considered, which predominantly included climate change and ozone depletion; iii) there was no consensus on the functional unit or the system boundaries; iv) the main gaseous emissions studied were ammonia, methane, and nitrogen oxide, which were generally determined by emission factors; v) the avoided environmental impacts associated with the end-product quality and its application as an organic amendment or soil improver were ignored. This work demonstrates the complexity of conducting credible and valid composting LCA studies and proposes seven recommendations for improving the application of this assessment methodology to analyze this waste management alternative.

RESUMO

Allium cepa L. is a commonly consumed vegetable that belongs to the Amaryllidaceae family and contains nutrients and antioxidants in ample amounts. In spite of the valuable food applications of onion bulb, its peel and outer fleshy layers are generally regarded as waste and exploration of their nutritional and therapeutic potential is still in progress with a very slow progression rate. The present study was designed with the purpose of doing a comparative analysis of the antioxidant potential of two parts of Allium cepa, i.g., bulb (edible part) and outer fleshy layers and dry peels (inedible part). Moreover, the inhibitory effect of the onion bulb and peel extracts on rat intestinal α-glucosidase and pancreatic α-amylase of porcine was also evaluated. The antioxidant potential of onion peel and bulb extracts were evaluated using 2,2-diphenyl- 1-picryl hydrazyl (DPPH), ferric-reducing antioxidant power assay (FRAP), 2,2-azino-bis- 3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical scavenging assay, H2O2 radical scavenging activity and Fe2+ chelating activity. Total flavonoids and phenolic content of ethanolic extract of onion peel were significantly greater as compared to that of onion bulb. Ethanolic extract of onion peel also presented better antioxidant and free-radical scavenging activity as compared to the ethanolic extract of bulb, while the aqueous extract of bulb presented weakest antioxidative potential. Onion peel extract's α-glucosidase inhibition potential was also correlated with their phenolic and flavonoid contents. The current findings presented onion peel as a possible source of antioxidative agents and phenolic compounds that might be beneficial against development of various common chronic diseases that might have an association with oxidative stress. Besides, outer dry layers and fleshy peels of onion exhibited higher phenolic content and antioxidant activities, compared [...].(AU)

Allium cepa pertence à família Liliaceae e é rica em nutrientes e antioxidantes. Apesar das expressivas aplicações alimentares do bulbo da cebola, sua casca e outras camadas externas são geralmente consideradas resíduos, e seu potencial nutricional e terapêutico ainda é pouco explorado. O presente estudo foi delineado com o objetivo de investigar comparativamente o potencial antioxidante de duas partes de Allium cepa, por exemplo o bulbo (parte comestível) e camadas externas e cascas secas (parte não comestível). Além disso, o efeito inibitório dos extratos do bulbo de cebola e casca sobre a α-glucosidase intestinal de ratos e α-amilase pancreática suína também foi avaliado. O potencial antioxidante dos extratos da casca de cebola e bulbo foi avaliado utilizando-se 2,2-difenil-1-picrilhidrazil (DPPH), método de poder antioxidante de redução do ferro (FRAP), método 2,2-azino-bis-3-etilbenzotiazolina-6-ácido sulfônico (ABTS) de eliminação de radicais, atividade de eliminação de radicais H2O2 e atividade quelante do Fe2+. Os flavonoides totais e os teores fenólicos do extrato de etanol da casca de cebola foram significativamente maiores quando comparados ao do bulbo. O extrato de etanol da casca de cebola também apresentou melhor atividade antioxidante e eliminação de radicais livres quando comparado ao extrato de etanol do bulbo, enquanto o extrato aquoso de bulbo apresentou menor potencial antioxidante. O potencial de inibição da α-glicosidase dos extratos de casca de cebola correlacionou-se com seus teores fenólicos e de flavonoides. Os resultados encontrados identificaram que a casca de cebola é uma possível fonte de agentes antioxidantes e compostos fenólicos que podem ser benéficos contra o desenvolvimento de várias doenças crônicas que estão associadas ao estresse oxidativo. Além disso, as camadas externas secas e as cascas da cebola exibiram maior conteúdo fenólico e atividades [...].(AU

Assuntos

RESUMO

Abstract Allium cepa L. is a commonly consumed vegetable that belongs to the Amaryllidaceae family and contains nutrients and antioxidants in ample amounts. In spite of the valuable food applications of onion bulb, its peel and outer fleshy layers are generally regarded as waste and exploration of their nutritional and therapeutic potential is still in progress with a very slow progression rate. The present study was designed with the purpose of doing a comparative analysis of the antioxidant potential of two parts of Allium cepa, i.g., bulb (edible part) and outer fleshy layers and dry peels (inedible part). Moreover, the inhibitory effect of the onion bulb and peel extracts on rat intestinal α-glucosidase and pancreatic α-amylase of porcine was also evaluated. The antioxidant potential of onion peel and bulb extracts were evaluated using 2,2-diphenyl- 1-picryl hydrazyl (DPPH), ferric-reducing antioxidant power assay (FRAP), 2,2'-azino-bis- 3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical scavenging assay, H2O2 radical scavenging activity and Fe2+ chelating activity. Total flavonoids and phenolic content of ethanolic extract of onion peel were significantly greater as compared to that of onion bulb. Ethanolic extract of onion peel also presented better antioxidant and free-radical scavenging activity as compared to the ethanolic extract of bulb, while the aqueous extract of bulb presented weakest antioxidative potential. Onion peel extract's α-glucosidase inhibition potential was also correlated with their phenolic and flavonoid contents. The current findings presented onion peel as a possible source of antioxidative agents and phenolic compounds that might be beneficial against development of various common chronic diseases that might have an association with oxidative stress. Besides, outer dry layers and fleshy peels of onion exhibited higher phenolic content and antioxidant activities, compared to the inner bulb. The information obtained by the present study can be useful in promoting the use of vegetable parts other than the edible mesocarp for several future food applications, rather than these being wasted.

Resumo Allium cepa pertence à família Liliaceae e é rica em nutrientes e antioxidantes. Apesar das expressivas aplicações alimentares do bulbo da cebola, sua casca e outras camadas externas são geralmente consideradas resíduos, e seu potencial nutricional e terapêutico ainda é pouco explorado. O presente estudo foi delineado com o objetivo de investigar comparativamente o potencial antioxidante de duas partes de Allium cepa, por exemplo o bulbo (parte comestível) e camadas externas e cascas secas (parte não comestível). Além disso, o efeito inibitório dos extratos do bulbo de cebola e casca sobre a α-glucosidase intestinal de ratos e α-amilase pancreática suína também foi avaliado. O potencial antioxidante dos extratos da casca de cebola e bulbo foi avaliado utilizando-se 2,2-difenil-1-picrilhidrazil (DPPH), método de poder antioxidante de redução do ferro (FRAP), método 2,2'-azino-bis-3-etilbenzotiazolina-6-ácido sulfônico (ABTS) de eliminação de radicais, atividade de eliminação de radicais H2O2 e atividade quelante do Fe2+. Os flavonoides totais e os teores fenólicos do extrato de etanol da casca de cebola foram significativamente maiores quando comparados ao do bulbo. O extrato de etanol da casca de cebola também apresentou melhor atividade antioxidante e eliminação de radicais livres quando comparado ao extrato de etanol do bulbo, enquanto o extrato aquoso de bulbo apresentou menor potencial antioxidante. O potencial de inibição da α-glicosidase dos extratos de casca de cebola correlacionou-se com seus teores fenólicos e de flavonoides. Os resultados encontrados identificaram que a casca de cebola é uma possível fonte de agentes antioxidantes e compostos fenólicos que podem ser benéficos contra o desenvolvimento de várias doenças crônicas que estão associadas ao estresse oxidativo. Além disso, as camadas externas secas e as cascas da cebola exibiram maior conteúdo fenólico e atividades antioxidantes, em comparação com o bulbo interno. As informações obtidas pelo presente estudo podem promover o uso de outras partes vegetais além do mesocarpo comestível para futuras aplicações em alimentos, ao invés de serem desperdiçadas.

Assuntos

RESUMO

Allium cepa L. is a commonly consumed vegetable that belongs to the Amaryllidaceae family and contains nutrients and antioxidants in ample amounts. In spite of the valuable food applications of onion bulb, its peel and outer fleshy layers are generally regarded as waste and exploration of their nutritional and therapeutic potential is still in progress with a very slow progression rate. The present study was designed with the purpose of doing a comparative analysis of the antioxidant potential of two parts of Allium cepa, i.g., bulb (edible part) and outer fleshy layers and dry peels (inedible part). Moreover, the inhibitory effect of the onion bulb and peel extracts on rat intestinal α-glucosidase and pancreatic α-amylase of porcine was also evaluated. The antioxidant potential of onion peel and bulb extracts were evaluated using 2,2-diphenyl- 1-picryl hydrazyl (DPPH), ferric-reducing antioxidant power assay (FRAP), 2,2’-azino-bis- 3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical scavenging assay, H2O2 radical scavenging activity and Fe2+ chelating activity. Total flavonoids and phenolic content of ethanolic extract of onion peel were significantly greater as compared to that of onion bulb. Ethanolic extract of onion peel also presented better antioxidant and free-radical scavenging activity as compared to the ethanolic extract of bulb, while the aqueous extract of bulb presented weakest antioxidative potential. Onion peel extract's α-glucosidase inhibition potential was also correlated with their phenolic and flavonoid contents. The current findings presented onion peel as a possible source of antioxidative agents and phenolic compounds that might be beneficial against development of various common chronic diseases that might have an association with oxidative stress. Besides, outer dry layers and fleshy peels of onion exhibited higher phenolic content and antioxidant activities, compared [...].

Allium cepa pertence à família Liliaceae e é rica em nutrientes e antioxidantes. Apesar das expressivas aplicações alimentares do bulbo da cebola, sua casca e outras camadas externas são geralmente consideradas resíduos, e seu potencial nutricional e terapêutico ainda é pouco explorado. O presente estudo foi delineado com o objetivo de investigar comparativamente o potencial antioxidante de duas partes de Allium cepa, por exemplo o bulbo (parte comestível) e camadas externas e cascas secas (parte não comestível). Além disso, o efeito inibitório dos extratos do bulbo de cebola e casca sobre a α-glucosidase intestinal de ratos e α-amilase pancreática suína também foi avaliado. O potencial antioxidante dos extratos da casca de cebola e bulbo foi avaliado utilizando-se 2,2-difenil-1-picrilhidrazil (DPPH), método de poder antioxidante de redução do ferro (FRAP), método 2,2’-azino-bis-3-etilbenzotiazolina-6-ácido sulfônico (ABTS) de eliminação de radicais, atividade de eliminação de radicais H2O2 e atividade quelante do Fe2+. Os flavonoides totais e os teores fenólicos do extrato de etanol da casca de cebola foram significativamente maiores quando comparados ao do bulbo. O extrato de etanol da casca de cebola também apresentou melhor atividade antioxidante e eliminação de radicais livres quando comparado ao extrato de etanol do bulbo, enquanto o extrato aquoso de bulbo apresentou menor potencial antioxidante. O potencial de inibição da α-glicosidase dos extratos de casca de cebola correlacionou-se com seus teores fenólicos e de flavonoides. Os resultados encontrados identificaram que a casca de cebola é uma possível fonte de agentes antioxidantes e compostos fenólicos que podem ser benéficos contra o desenvolvimento de várias doenças crônicas que estão associadas ao estresse oxidativo. Além disso, as camadas externas secas e as cascas da cebola exibiram maior conteúdo fenólico e atividades [...].

Assuntos

RESUMO

Abstract Allium cepa L. is a commonly consumed vegetable that belongs to the Amaryllidaceae family and contains nutrients and antioxidants in ample amounts. In spite of the valuable food applications of onion bulb, its peel and outer fleshy layers are generally regarded as waste and exploration of their nutritional and therapeutic potential is still in progress with a very slow progression rate. The present study was designed with the purpose of doing a comparative analysis of the antioxidant potential of two parts of Allium cepa, i.g., bulb (edible part) and outer fleshy layers and dry peels (inedible part). Moreover, the inhibitory effect of the onion bulb and peel extracts on rat intestinal -glucosidase and pancreatic -amylase of porcine was also evaluated. The antioxidant potential of onion peel and bulb extracts were evaluated using 2,2-diphenyl- 1-picryl hydrazyl (DPPH), ferric-reducing antioxidant power assay (FRAP), 2,2-azino-bis- 3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical scavenging assay, H2O2 radical scavenging activity and Fe2+ chelating activity. Total flavonoids and phenolic content of ethanolic extract of onion peel were significantly greater as compared to that of onion bulb. Ethanolic extract of onion peel also presented better antioxidant and free-radical scavenging activity as compared to the ethanolic extract of bulb, while the aqueous extract of bulb presented weakest antioxidative potential. Onion peel extracts -glucosidase inhibition potential was also correlated with their phenolic and flavonoid contents. The current findings presented onion peel as a possible source of antioxidative agents and phenolic compounds that might be beneficial against development of various common chronic diseases that might have an association with oxidative stress. Besides, outer dry layers and fleshy peels of onion exhibited higher phenolic content and antioxidant activities, compared to the inner bulb. The information obtained by the present study can be useful in promoting the use of vegetable parts other than the edible mesocarp for several future food applications, rather than these being wasted.

Resumo Allium cepa pertence à família Liliaceae e é rica em nutrientes e antioxidantes. Apesar das expressivas aplicações alimentares do bulbo da cebola, sua casca e outras camadas externas são geralmente consideradas resíduos, e seu potencial nutricional e terapêutico ainda é pouco explorado. O presente estudo foi delineado com o objetivo de investigar comparativamente o potencial antioxidante de duas partes de Allium cepa, por exemplo o bulbo (parte comestível) e camadas externas e cascas secas (parte não comestível). Além disso, o efeito inibitório dos extratos do bulbo de cebola e casca sobre a -glucosidase intestinal de ratos e -amilase pancreática suína também foi avaliado. O potencial antioxidante dos extratos da casca de cebola e bulbo foi avaliado utilizando-se 2,2-difenil-1-picrilhidrazil (DPPH), método de poder antioxidante de redução do ferro (FRAP), método 2,2'-azino-bis-3-etilbenzotiazolina-6-ácido sulfônico (ABTS) de eliminação de radicais, atividade de eliminação de radicais H2O2 e atividade quelante do Fe2+. Os flavonoides totais e os teores fenólicos do extrato de etanol da casca de cebola foram significativamente maiores quando comparados ao do bulbo. O extrato de etanol da casca de cebola também apresentou melhor atividade antioxidante e eliminação de radicais livres quando comparado ao extrato de etanol do bulbo, enquanto o extrato aquoso de bulbo apresentou menor potencial antioxidante. O potencial de inibição da -glicosidase dos extratos de casca de cebola correlacionou-se com seus teores fenólicos e de flavonoides. Os resultados encontrados identificaram que a casca de cebola é uma possível fonte de agentes antioxidantes e compostos fenólicos que podem ser benéficos contra o desenvolvimento de várias doenças crônicas que estão associadas ao estresse oxidativo. Além disso, as camadas externas secas e as cascas da cebola exibiram maior conteúdo fenólico e atividades antioxidantes, em comparação com o bulbo interno. As informações obtidas pelo presente estudo podem promover o uso de outras partes vegetais além do mesocarpo comestível para futuras aplicações em alimentos, ao invés de serem desperdiçadas.

RESUMO

The "Kurugua" (Sicana odorifera) is a native fruit that demonstrates attractive nutritional, coloring, flavoring, and antioxidant properties. The main by-products from the processing and consumption of kurugua fruit are epicarp and seeds. In this work, the properties of the seeds of S. odorifera were evaluated. The nutritional composition of the fruit seeds was determined through AOAC official methods and UHPLC-ESI-MS/MS profiling. The antioxidant activities were determined using in vitro methods, and the acute toxicity and hepatoprotective properties were investigated in Swiss albino mice. Quercetin derivatives and cucurbitacins were the main phytochemicals in the seeds' methanolic extract and demonstrated some biological activities. GC-MS analysis revealed the essential fatty acids linolenic and linoleic as the main compounds present in seeds oil. The methanolic extract significantly reduced the serum levels of glutamic-pyruvic transaminase (GPT) and glutamic-oxaloacetic transaminase (GOT) in mice with induced hepatotoxicity (GPT p < 0.05; GOT p < 0.001) at the minor concentration tested (100 mg/kg EMSo). The results suggest that the S. odorifera seeds as by-products show potential use as a source of phytochemicals and in the production of oils with application in food supplements and nutraceuticals. Their integral use could contribute to waste reduction from kurugua fruits processing within the food safety and environmental sustainability framework.

RESUMO

The minimum set of parameters that can be used to assess the adsorption capacity of activated carbon (AC) produced from termite bio-waste was determined. Three types of AC were prepared: AC600 at 600 °C, MAC600 at the same temperature and impregnated with FeCl3, and AC800 at 800 °C. The influence of the solution pH on the adsorption, adsorption kinetics, isotherms and thermodynamic parameters was considered to characterize the amoxicillin (AMX) adsorption process. The AC materials had surface areas (m2 g-1) of approximately 248.8 for AC600, 501.6 for AC800 and 269.5 for MAC600, with point of zero charge (pHPZC) values of 8.3, 7.5 and 1.7, respectively. A time period of 30 min was chosen for the adsorption kinetics, which was best represented by the pseudo-first-order model for AC600, the intraparticle diffusion model for AC800 and the pseudo-second-order model for MAC600. Regarding the isotherms, a maximum adsorption of 23.4 mg g-1 was found for AC800. In general, the thermodynamic parameters demonstrated a non-spontaneous process. It seems that the medium conditions, the adsorbate and adsorbent characteristics, and the Gibbs free energy are the most important parameters to be considered in a preliminary assessment of the adsorption efficiency of specific adsorbent/adsorbate pairs.

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In this work, we prepared PU-composites with Australian palm residues (PR) in different contents (5, 10, 15, and 20 wt%) and granulometry (28 and 35 mesh) to improve the oil (crude oil and S500 Diesel) sorption capacity. The foams were characterized by life cycle assessment (LCA), scanning electron microscopy, oil sorption, desorption, and Langmuir, Freundlich, and Temkin sorption isotherms. LCA indicated that higher PR contents decreased the foam environmental impacts than the classical residue handling, indicating that 20 wt% PR is the better environmental option, independent of the residues granulometry. The PR incorporation into PU foams resulted in smaller pore sizes, with a higher number of homogeneous open-cells. The PU composites exhibited higher oil adsorption capacity than the pristine foam. The PU sample showed maximum absorption capability of 6.1 and 6.7 g g-1 for diesel S500 and crude oil, and the composites showed increased values of ∼18 g g-1 and ∼24 g g-1. The Langmuir model presented the best fit and predicted a maximum adsorption capacity of 30.39 and 25.57 g g-1 for PU-20% PR 28 and 35 mesh, respectively. The composites presented excellent reusability with PU-20% PR (28 mesh) and PU-20% PR (35 mesh), showing removal efficiency after 16 and 9 cycles, respectively. The results classify the developed foams as excellent materials to sorb spilled crude oil in marine accidents.

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The advanced glycation end products (AGEs) constitute a wide variety of substances synthesized from interactions between amino groups of proteins and reducing sugars, which excess induces pathogenesis of chronic diseases. Brazil is the major producer of citrus, a low-cost source of hesperidin, which is a polyphenol recognized for its capacity to inhibit AGEs formation. This is the first work to evaluate the effects of a polyphenolic fraction derived from citrus wastes on the antiglycation and on the inhibition properties of digestive enzymes on the possibility to process these wastes in high value-added products. At concentrations of 10, 15 and 20 mg/mL inhibition of AGEs was higher than 60%. The extracts were able to inhibit by 76% the activity of pancreatic lipase and by 98% the activity of α-glucosidase. For the α-amylase the inhibition capacity was lower than 50%. Strong correlation was obtained among anti-glycation with polyphenolic content and antioxidant capacity.

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RESUMO

In this study, the supercritical CO2-based extraction approach was used from the green technologies to extract Oregano oil (Origanum vulgare L.). A Taguchi experimental design was applied to evaluate the effect of pressure, temperature and ethanol as co-solvent. High yield of oregano oil (13.40%) was obtained at 40 °C, 100 bar and 8 g min-1 of co-solvent flow. Fatty acids profile include α-linolenic, palmitic, oleic and linoleic that contribute to 70.9-76.8% of total fatty acids. Volatile compounds including carvacrol (29.99%), heneicosane (8.21%), nonacosane (11.78%), docosane (7.18%), borneol (4.35%) and thymol (4.51%) were the main compounds identified. Antimicrobial activity assays showed that extracts obtained at 40 °C were highly efficient against S. aureus, E. coli, and C. albicans. Highest antioxidant activities on DPPH and FRAP assays were reached under 8 g min-1 of co-solvent flow (6.08 and 6.89 µmol TE g-1 extract, respectively). On the other hand, antioxidant activity (35.76 µmol TE g-1) on ABTS assay was improved at 40 °C, 100 bar, and 4 g min-1 of co-solvent flow.

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Strategies are needed to increase the sustainability of phosphorus (P) fertiliser management in agriculture. This paper reports on the potential of pyrolysis treatment to recycle P from renewable materials previously regarded as wastes. The study used K-edge X-ray absorption near-edge structure (XANES) spectroscopy to examine chemical forms of P in the waste feedstock materials and corresponding biochars (pyrolysis at 480-500 °C) of four ligno-cellulosic, plant-based residues and five relatively P-rich livestock and water-treatment by-products, to acquire information on changes in potential P fertiliser value. Pyrolysis enriched P in the biochars by factors of 1.3-4.3, thus offering wide-ranging P fertiliser potential. XANES spectroscopy revealed hydroxyapatite (HAP) as one of the dominant chemical P compounds in the feedstocks, ranging from 14% (rice husks) to 98% (animal bone) of total P. For most materials, pyrolysis increased the proportion of HAP, and pyrophosphates were generated in several cases. These alterations possibly lead to diversity in the P solubility characteristics of the biochars if used as soil amendments; this is an important property of environmentally sound P fertilisers.

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Biowaste is commonly the largest fraction of municipal solid waste (MSW) in developing countries. Although composting is an effective method to treat source separated biowaste (SSB), there are certain limitations in terms of operation, partly due to insufficient control to the variability of SSB quality, which affects process kinetics and product quality. This study assesses the variability of the SSB physicochemical quality in a composting facility located in a small town of Colombia, in which SSB collection was performed twice a week. Likewise, the influence of the SSB physicochemical variability on the variability of compost parameters was assessed. Parametric and non-parametric tests (i.e. Student's t-test and the Mann-Whitney test) showed no significant differences in the quality parameters of SSB among collection days, and therefore, it was unnecessary to establish specific operation and maintenance regulations for each collection day. Significant variability was found in eight of the twelve quality parameters analyzed in the inlet stream, with corresponding coefficients of variation (CV) higher than 23%. The CVs for the eight parameters analyzed in the final compost (i.e. pH, moisture, total organic carbon, total nitrogen, C/N ratio, total phosphorus, total potassium and ash) ranged from 9.6% to 49.4%, with significant variations in five of those parameters (CV>20%). The above indicate that variability in the inlet stream can affect the variability of the end-product. Results suggest the need to consider variability of the inlet stream in the performance of composting facilities to achieve a compost of consistent quality.

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RESUMO

In the present study, rapid reduction and stabilization of Ag+ ions with different NaOH molar concentration (0.5 mM, 1.0 mM and 1.5 mM) has been carried out in the aqueous solution of silver nitrate by the bio waste peel extract of P.granatum. Generally, chemical methods used for the synthesis of AgNPs are quite toxic, flammable and have adverse effect in medical application but green synthesis is a better option due to eco-friendliness, non-toxicity and safe for human. Stable AgNPs were synthesized by treating 90 mL aqueous solution of 2 mM AgNO3 with the 5 mL plant peels extract (0.4% w/v) at different NaOH concentration (5 mL). The synthesized AgNPs were characterized by UV-Vis spectroscopy, TEM and SEM. Further, antimicrobial activities of AgNPs were performed on Gram positive i.e. Staphylococcus aureus, Bacillus subtilius and Gram negative i.e. E. coli, Pseudomonas aeruginosa bacteria. The AgNPs synthesized at 1.5 mM NaOH concentration had shown maximum zone of inhibition (ZOI) i.e. 49 ± 0.64 in E. coli, whereas Pseudomonas aeruginosa, Staphylococcus aureus and Bacillus subtilius had shown 40 ± 0.29 mm, 28 ± 0.13 and 42 ± 0.49 mm ZOI respectively. The MIC value of 30 g/mL observed for E. coli Whereas, Staphylococcus aureus, Bacillus subtilius and Pseudomonas aeruginosa had shown 45 µg/mL, 38 µg/mL, 35 µg/mL respectively. The study revealed that AgNPs had shown significant antimicrobial activity as compared to Streptomycin.

Assuntos

RESUMO

In the present study, rapid reduction and stabilization of Ag+ ions with different NaOH molar concentration (0.5 mM, 1.0 mM and 1.5 mM) has been carried out in the aqueous solution of silver nitrate by the bio waste peel extract of P.granatum. Generally, chemical methods used for the synthesis of AgNPs are quite toxic, flammable and have adverse effect in medical application but green synthesis is a better option due to eco-friendliness, non-toxicity and safe for human. Stable AgNPs were synthesized by treating 90 mL aqueous solution of 2 mM AgNO3 with the 5 mL plant peels extract (0.4% w/v) at different NaOH concentration (5 mL). The synthesized AgNPs were characterized by UV-Vis spectroscopy, TEM and SEM. Further, antimicrobial activities of AgNPs were performed on Gram positive i.e. Staphylococcus aureus, Bacillus subtilius and Gram negative i.e. E. coli, Pseudomonas aeruginosa bacteria. The AgNPs synthesized at 1.5 mM NaOH concentration had shown maximum zone of inhibition (ZOI) i.e. 49 ± 0.64 in E. coli, whereas Pseudomonas aeruginosa, Staphylococcus aureus and Bacillus subtilius had shown 40 ± 0.29 mm, 28 ± 0.13 and 42 ± 0.49 mm ZOI respectively. The MIC value of 30 g/mL observed for E. coli Whereas, Staphylococcus aureus, Bacillus subtilius and Pseudomonas aeruginosa had shown 45 µg/mL, 38 µg/mL, 35 µg/mL respectively. The study revealed that AgNPs had shown significant antimicrobial activity as compared to Streptomycin.

Assuntos

RESUMO

In the present study, rapid reduction and stabilization of Ag+ ions with different NaOH molar concentration (0.5 mM, 1.0 mM and 1.5 mM) has been carried out in the aqueous solution of silver nitrate by the bio waste peel extract of P.granatum. Generally, chemical methods used for the synthesis of AgNPs are quite toxic, flammable and have adverse effect in medical application but green synthesis is a better option due to eco-friendliness, non-toxicity and safe for human. Stable AgNPs were synthesized by treating 90 mL aqueous solution of 2 mM AgNO3 with the 5 mL plant peels extract (0.4% w/v) at different NaOH concentration (5 mL). The synthesized AgNPs were characterized by UV-Vis spectroscopy, TEM and SEM. Further, antimicrobial activities of AgNPs were performed on Gram positive i.e. Staphylococcus aureus, Bacillus subtilius and Gram negative i.e. E. coli, Pseudomonas aeruginosa bacteria. The AgNPs synthesized at 1.5 mM NaOH concentration had shown maximum zone of inhibition (ZOI) i.e. 49 ± 0.64 in E. coli, whereas Pseudomonas aeruginosa, Staphylococcus aureus and Bacillus subtilius had shown 40 ± 0.29 mm, 28 ± 0.13 and 42 ± 0.49 mm ZOI respectively. The MIC value of 30 µg/mL observed for E. coli Whereas, Staphylococcus aureus, Bacillus subtilius and Pseudomonas aeruginosa had shown 45 µg/mL, 38 µg/mL, 35 µg/mL respectively. The study revealed that AgNPs had shown significant antimicrobial activity as compared to Streptomycin.

Assuntos