Systematic surveillance tools to reduce rodent pests in disadvantaged urban areas can empower communities and improve public health.

Rodents are notorious pests, known for transmitting major public health diseases and causing agricultural and economic losses. The lack of site-specific and national standardised rodent surveillance in several disadvantaged communities has rendered interventions targeted towards rodent control as often ineffective. Here, by using the example from a pilot case-study in the Bahamas, we present a unique experience wherein, through multidisciplinary and community engagement, we simultaneously developed a standardised national surveillance protocol, and performed two parallel but integrated activities: (1) eight days of theoretical and practical training of selected participants; and (2) a three-month post-training pilot rodent surveillance in the urban community of Over-the-Hill, Nassau, The Bahamas. To account for social and environmental conditions influencing rodent proliferation in the Bahamas, we engaged selected influential community members through a semi-structured interview and gathered additional site-specific information using a modified Centers for Diseases Control and Prevention (CDC) exterior and interior rodent evaluation form, along with other validated instruments such as tracking plates and snap trapping, to test and establish a standardised site-specific rodent surveillance protocol tailored for the Bahamas. Our engagement with community members highlighted poor disposal of animal and human food, irregular garbage collection, unapproved refuse storage, lack of accessible dumpsters, poor bulk waste management, ownership problems and structural deficiencies as major factors fuelling rodent proliferation in the study areas. Accordingly, results from our pilot survey using active rodent signs (that is, the presence of rodent runs, burrows, faecal material or gnawed material) as a proxy of rodent infestation in a generalized linear model confirmed that the variables earlier identified during the community engagement program as significantly correlated with rodent activities (and capturing) across the study areas. The successful implementation of the novel site-specific protocol by trained participants, along with the correlation of their findings with those recorded during the community engagement program, underscores its suitability and applicability in disadvantaged urban settings. This experience should serve as a reference for promoting a standardised protocol for monitoring rodent activities in many disadvantaged urban settings of the Global South, while also fostering a holistic understanding of rodent proliferation. Through this pilot case-study, we advocate for the feasibility of developing sustainable rodent control interventions that are acceptable to both local communities and public authorities, particularly through the involvement of a multidisciplinary team of professionals and community members.

Investigation of biochemical, enzymatic, and metagenomic profiles of garbage enzymes and its application in dumping site leachate treatment.

The current article focuses on the preparation and characterization of garbage enzyme (GE) and explores its applications in treating leachate. GE is prepared from fruit and vegetable wastes and characterized via analysis of metabolites, carbohydrates, proteins, antioxidants, and enzymatic activities. This study extends our understanding of GE by reporting the presence of various metabolites. Moreover, a metagenomic analysis of GE is presented, shedding light on the microbial diversity. Firmicutes emerged as the dominant phylum, surpassing other phyla, including Proteobacteria and Actinobacteria. When exploring the potential for leachate treatment, the results indicate that vegetable GE shows 68% reduction in COD (chemical oxygen demand) and 39% reduction in ammoniacal nitrogen. Similarly, non-citrus GE also showed 64% reduction in COD and a 37% reduction in ammoniacal nitrogen, followed by citrus GE with a 33% reduction in COD and a 34% reduction in ammoniacal nitrogen compared to the control.

Native and ornamental exotic resources in pollen loads and garbage pellets of four stingless bees (Apidae, Meliponini) in an urban environment with riparian native forest.

An entomopalynological study to assess pollen use by wild bees was performed in an urban environment with riparian native forest in the Chaco region of Argentina. A combined method for sampling pollen loads and garbage pellets at nest entrances in four stingless bees with different entrance size and forager traffic was here successfully used. Sampling was carried out in a short period of time (late winter) and located within a distance of 50 m. Pollen analysis using acetolysis showed that most identified pollen types (31) were from native species, 12 from ornamental exotic species, 5 included native and ornamental exotic species and 18 of uncertain status. A much broader pollen spectrum was present in garbage pellets (62 types) than loads (14 types). A few resources from previous blooming (late spring-summer) were identified in garbage pellets, which were mainly composed of current flowerings. From the 66 pollen types found in all samples, many (18) remained unidentified due to the complex nature of the vegetation surrounding the nests and the generalist behaviour of these bees. The versatile foraging behaviour on spontaneous (mostly native) and cultivated (mostly ornamental exotic) pollen resources is an important issue for the conservation and rearing of stingless bee colonies in urban habitats where native flora is preserved, particularly the riparians, where a high richness of blooming plants is available.

Extração assistida por ultrassom de casca de pitaya vermelha: fenólicos totais e capacidade antioxidante / Ultrasound assisted extraction of red pitaya peel: total phenolics and antioxidant capacity

Objetivou-se com o presente estudo, avaliar a eficiência da extração assistida por ultrassom no teor de fenólicos totais e na capacidade antioxidante na casca de pitaya em água e solução hidroetanólica em diferentes proporções, pelo método ABTS•+ e sistema β-caroteno/ácido linoleico. A extração da casca de pitaya em água (33,02±0,35 mg EAG.100 g-1) não diferiu do hidroetanólico 60% (31,34±1,68 mg EAG.100 g-1) e 70% (28,36±0,12 mg EAG.100 g-1) para fenólicos totais e pelo método ABTS•+ (20,82±1,02; 22,97±1,02 e 27,26±1,21 CE50 mg.mL-1, respectivamente), entretanto, a amostra aquosa apresentou maior percentual de inibição de oxidação (95,74±0,04) pelo sistema β-caroteno/ácido linoleico. O resíduo tem potencial para ser utilizado como ingrediente funcional no desenvolvimento de novos produtos na indústria alimentícia.

Atividade bactericida e bacteriostática da casca do pequi (Caryocar brasiliense) em bactérias deteriorantes e patogênicas isoladas de alimentos / Bactericidal and bacteriostatic activity of pequi (Caryocar brasiliense) against deteriorant and pathogenic bacteria from foods

O pequi é uma fruta nativa do Cerrado brasileiro que apresenta elevado teor de compostos antioxidantes e pode apresentar ação antimicrobiana. Dessa forma, objetivou-se com o presente trabalho avaliar a atividade bacteriostática e bactericida do extrato da casca do pequi. Das cepas estudadas 5 são padrões cedidos pela FIOCRUZ e 5 são bactérias de alta resistência a antimicrobianos isoladas de carne e frango. Foi determinada a concentração inibitória mínima (CIM) e concentração bactericida mínima do extrato da casca do pequi. O extrato da casca do pequi apresenta atividade antimicrobiana frente a bactérias patogênicas e deteriorantes. C. jejuni e C. colisão as mais sensíveis. S. aureus apresentou tolerância. E. coli O157:H7 e E. coli são menos sensíveis. O resíduo do pequi é uma potencial e importante fonte de antimicrobianos naturais.

Ação do extrato do resíduo de Caryocar brasiliense frente a formação de biofilme dos principais microrganismos veiculados por produtos de origem animal / Action of the Caryocar brasiliense waste extract against the biofilm formation of the main microorganisms carried by products of animal origin

Objetivou-se com o presente estudo avaliar a inibição da formação de biofilme pelo extrato do resíduo do pequi frente a microrganismos patogênicos e deteriorantes de alimentos. A casca do pequi foi obtida de frutas coletadas na cidade de Montes Claros/MG, foi seca em estufa de ventilação forçada, moída e peneirada em 250 Mesh. Seu extrato foi obtido em micro-ondas analítico. Foram utilizadas cinco cepas padrão e cinco isolados de produtos de origem animal, que foram reativadas e confirmado a sua pureza em ágar específico. Para avaliar a formação do biofilme foram utilizadas microplacas esterilizadas, sendo adicionados 90µL de BHI com 1% de glicose, 10µL da suspensão de cada bactéria e o extrato em diferentes concentrações. Concluiu-se que o extrato da casca do pequi inibe a formação de biofilme por bactérias patogênicas e deteriorantes.

Fuzzy modeling and parameters optimization for the enhancement of biodiesel production from waste frying oil over montmorillonite clay K-30.

Transesterification is a promising technology for the biodiesel production to provide an alternative fuel that considers the environmental concerns. From the economic and environmental protection points of view, utilization of waste frying oil for the production of biodiesel addresses very beneficial impacts. Production of higher yield of biodiesel is a challenging process in order to commercialize it with a lower cost. The current study focuses on the influence of different parameters such as reaction temperature (°C), reaction period (min), oil to methanol ratio and amount of catalyst (wt%) on the production of biodiesel. The main objective of this work is to develop a model via fuzzy logic approach in order to maximize the biodiesel produced from waste frying oil using montmorillonite Clay K-30 as a catalyst. The optimization for the operating parameters has been performed via particle swarm optimization (PSO) approach. During the optimization process, the decision variables were represented by four different operating parameters: temperature (40-140 °C), reaction period (60-300 min), oil/methanol ratio (1:6-1:18) and amount of catalyst (1-5 wt%). The model has been validated with the experimental data and compared with the optimal results reported based on other optimization techniques. Results showed the increment of biodiesel production by 15% using the proposed strategy compared to the earlier study. The obtained biodiesel production yield reached 93.70% with the optimal parameters for a temperature at 69.66 °C, a reaction period of 300 min, oil/methanol ratio of 1:9 and an amount of catalyst of 5 wt%.

Impact of trace element supplementation on mesophilic anaerobic digestion of food waste using Fe-rich inoculum.

Trace elements (TEs) play an indispensable role in enhancing the stability of anaerobic digestion (AD) of food waste (FW). Significant research on AD of FW with TE supplementation has been conducted with low Fe content inoculum. However, the use of Fe-rich inoculum is inevitable due to chemical phosphorous removal from wastewater in North America. We conducted comprehensive mesophilic batch tests to investigate the effect of TEs (Fe, Ni, Co, Se, and Mo) on FW digestion inoculated with Fe-rich sludge (≥ 1000 mg Fe L-1). This paper presents the impact of supplementing various concentrations of TEs on specific methanogenic activity (SMA), maximum specific methane production rate (SMPRmax), and apparent hydrolysis rate constant (Kh). The addition of TEs adversely impacted methanogenic activity by 20 to 58% in the SMA tests. The effects of individual and mixed supplementation of TEs on the SMPRmax and Kh during FW digestion were negligible; exceptions include Fe, Mo, and Co. Final soluble TE concentrations were 10-29% of the initial soluble TEs. The high Fe concentration in the inoculum reduces the bioavailable fraction of added TEs via coprecipitation. Contrary with many literature reports indicating the need to supplement TE to improve FW digestion efficiency, with Fe-rich sludges, FW digestion does not require TE supplementation.

Diagnóstico e tratamento de Sialolitíase: relato de caso / Diagnosis and treatment of Sialolithiasis: Case Report

Sialolitos são estruturas calcificadas, que se desenvolvem no interior do sistema ductal salivar, em decorrência da deposição de sais de cálcio ao redor de um acúmulo de restos orgânicos no lúmen do ducto glandular. Acometem, com mais assiduidade, a glândula submandibular e são a causa mais comum de inflamações agudas ou crônicas nas glândulas salivares maiores. Manifestam-se, com maior frequência, em indivíduos adultos de meia-idade, e os sinais e sintomas mais comuns são a dor e a tumefação local. Podem ser evidenciados por radiografias convencionais, tomografia computadorizada, ressonância magnética, ultrassonografia, cintilografia, sialoendoscopia e sialografia. O tratamento inclui a eliminação espontânea mediante orientações ou uso de medicamentos, ou a remoção cirúrgica do sialolito, sendo necessária, em alguns casos, a exérese da própria glândula. Este trabalho tem como objetivo relatar o caso clínico do paciente S.L.M, 44 anos de idade, sexo feminino, caucasiana, atendida na clínica de Cirurgia Bucal da Universidade Federal Fluminense, apresentando um sialolito no sistema ductal da glândula submandibular do lado esquerdo. A paciente foi submetida à remoção cirúrgica do sialolito sob anestesia local, sem maiores intercorrências... (AU)

Sialolites are calcified structures that develop inside the salivary ductal system, due to the deposition of calcium salts around an accumulation of organic remains in the lumen of the glandular duct. They have a more frequent involvement of the submandibular gland and are the most common cause of acute or chronic inflammation in the major salivary glands. They occur more frequently in middle-aged adult patients and the most common signs and symptoms are local pain and swelling. They can be evidenced by conventional radiography, computed tomography, MRI, ultrasonography, scintigraphy, sialoendoscopy and sialography. Treatment includes spontaneous elimination, from guidelines or use of medications, or surgical removal of sialolite, in some cases, the excision of the gland itself. This study aims to report the clinical case of the patient S.L.M, 44 years old, female, Caucasian, attended at the Oral Surgery Clinic of the Federal Fluminense University, presenting a sialolite in the ductal system of the left submandibular gland. The patient was submitted to surgical removal of the sialolite, under local anesthesia, without major intercurrences... (AU)

Preparation and characterisation of activated carbon from waste tea by physical activation using steam.

In this study, the feasibility of preparing activated carbon from waste tea by physical activation using steam was investigated. The effects of activation temperature on yield and pore properties of the prepared activated carbon were studied. The yield decreased with increased activation temperature owing to the decomposition of cellulose and hemicellulose. The specific surface area and pore volume of the activated carbon were estimated using the Brunauer-Emmett-Teller method, Langmuir equation, and t-plot method. The specific surface area and micropore volume increased with increases in activation temperature, as additional volatile materials were released. The specific surface area significantly decreased at first but slightly increased with increasing activation time. The maximum specific surface area reached 995 m2/g at an activation temperature of 800 °C with a water flow rate of 0.075 g/min and a constant hold time of 0.5 hr. According to the nitrogen adsorption isotherms, micropores mainly developed when the activation temperature was below 800 °C, and both micropores and mesopores developed when it was above 800 °C. The results showed that activation temperature significantly affected micropore and mesopore volumes, as well as the specific surface area of the activated carbon. Overall, waste tea was found to be an attractive raw material for producing low-cost activated carbon. Implications: Every year, a large amount of waste tea is generated after extraction. The high carbon content of waste tea showed that it can be used as raw material to produce activated carbon. This study investigated the feasibility of preparing activated carbon from waste tea by physical activation using steam. Temperature and time were found to have clear effects on pore properties. Our proposed method and raw material are more environmentally friendly and involve low cost. Furthermore, this offers a potential solution to the problems of waste tea disposal and low-cost activated carbon production.

Investigation of the impact of trace elements on anaerobic volatile fatty acid degradation using a fractional factorial experimental design.

The requirement of trace elements (TE) in anaerobic digestion process is widely documented. However, little is understood regarding the specific requirement of elements and their critical concentrations under different operating conditions such as substrate characterisation and temperature. In this study, a flask batch trial using fractional factorial design is conducted to investigate volatile fatty acids (VFA) anaerobic degradation rate under the influence of the individual and combined effect of six TEs (Co, Ni, Mo, Se, Fe and W). The experiment inoculated with food waste digestate, spiked with sodium acetate and sodium propionate both to 10 g/l. This is followed by the addition of a selection of the six elements in accordance with a 26-2 fractional factorial principle. The experiment is conducted in duplicate and the degradation of VFA is regularly monitored. Factorial effect analysis on the experimental results reveals that within these experimental conditions, Se has a key role in promoting the degradation rates of both acetic and propionic acids; Mo and Co are found to have a modest effect on increasing propionic acid degradation rate. It is also revealed that Ni shows some inhibitory effects on VFA degradation, possibly due to its toxicity. Additionally, regression coefficients for the main and second order effects are calculated to establish regression models for VFA degradation.

Fractionation of phosphorus in soils amended with poultry manure co-composted with sugarcane and cabbage wastes / Fracionamento de fósforo em solos corrigidos com esterco de aves co-compostado com resíduos de cana de açúcar e repolho

Organic waste recycling is a viable option for reducing energy usage, volume of landfills, air and water pollution, greenhouse gas emissions and preserving natural resources for future use. Composting is an easy and natural bio-degradation process that converts organic wastes into available nutrients for plants. We studied the changes in phosphorus (P) fractions in soils amended with poultry manure co-composted with sugarcane and cabbage wastes. The compost was applied to sandy clay and silt loam soils at 10 and 20 t ha-1. Soils were then incubated at room temperature for 8 weeks when mineralization was expected and analyzed for extractable P fractions. The P fractions in the soils varied in the order HCl-P (Ca+Mg-bound) > H2O-P (water soluble) > NaHCO3-P (readily plant-available P) > NaOH-P (Fe+Albound) and the fractions increased significantly as compost application rates increased and decreased as the amount of sugarcane and cabbage wastes in the compost increased. Phosphorus was less concentrated in the compost containing CW than that containing SW and was higher in sandy clay than silty loam soil. The overall results showed that composting reduced the bio-availability of P from poultry litter and would be beneficial for optimizing P fertility in soil and minimizing losses to the environment.

A reciclagem de resíduos orgânicos é uma opção viável para reduzir o uso de energia, o volume de aterros sanitários, a poluição do ar e da água, as emissões de gases de efeito estufa e a preservação dos recursos naturais para uso futuro. A compostagem é um processo fácil e natural de biodegradação que converte resíduos orgânicos em nutrientes disponíveis para plantas. Estudamos as alterações nas frações de fósforo (P) em solos alterados com esterco de aves de capoeira co-compostada com resíduos de cana de açúcar e repolho. O composto foi aplicado em solos arenosos, argilosos e limosos com 10 e 20 t ha-1. Os solos foram então incubados à temperatura ambiente durante 8 semanas quando a mineralização era esperada e analisada para as frações de P extraíveis. As frações de P nos solos variaram na ordem HCl- P (Ca + Mg-bound) > H2O-P (solúvel em água) > NaHCO3-P ( P prontamente disponível para a planta) > NaOH-P (Fe + Al-bound) e as frações aumentaram significativamente à medida que as taxas de aplicação de composto aumentaram e diminuíram à medida que aumentou a quantidade de resíduos de cana de açúcar e de repolho na compostagem. O fósforo estava menos concentrado no composto contendo CW do que o que continha SW e era mais alto em argila arenosa do que o solo limoso. Os resultados globais mostraram que a compostagem reduziu a biodisponibilidade do P vindo do lixo de aves de capoeira e seria benéfica para otimizar a fertilidade do P no solo e minimizar as perdas para o meio ambiente.

Innovative "Green" and Novel Strategies for the Extraction of Bioactive Added Value Compounds from Citrus Wastes-A Review.

Citrus is a major processed crop that results in large quantities of wastes and by-products rich in various bioactive compounds such as pectins, water soluble and insoluble antioxidants and essential oils. While some of those wastes are currently valorised by various technologies (yet most are discarded or used for feed), effective, non-toxic and profitable extraction strategies could further significantly promote the valorisation and provide both increased profits and high quality bioactives. The present review will describe and summarize the latest works concerning novel and greener methods for valorisation of citrus by-products. The outcomes and effectiveness of those technologies such as microwaves, ultrasound, pulsed electric fields and high pressure is compared both to conventional valorisation technologies and between the novel technologies themselves in order to highlight the advantages and potential scalability of these so-called "enabling technologies". In many cases the reported novel technologies can enable a valorisation extraction process that is "greener" compared to the conventional technique due to a lower energy consumption and reduced utilization of toxic solvents.

A systematic approach to evaluate parameter consistency in the inlet stream of source separated biowaste composting facilities: A case study in Colombia.

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.

Anaerobic co-digestion of spent coffee grounds with different waste feedstocks for biogas production.

Proper management of spent coffee grounds has become a challenging problem as the production of this waste residue has increased rapidly worldwide. This study investigated the feasibility of the anaerobic co-digestion of spent coffee ground with various organic wastes, i.e., food waste, Ulva, waste activated sludge, and whey, for biomethanation. The effect of co-digestion was evaluated for each tested co-substrate in batch biochemical methane potential tests by varying the substrate mixing ratio. Co-digestion with waste activated sludge had an apparent negative effect on both the yield and production rate of methane. Meanwhile, the other co-substrates enhanced the reaction rate while maintaining methane production at a comparable or higher level to that of the mono-digestion of spent coffee ground. The reaction rate increased with the proportion of co-substrates without a significant loss in methanation potential. These results suggest the potential to reduce the reaction time and thus the reactor capacity without compromising methane production.

Elements affecting food waste in the food service sector.

Avoidable food waste is produced in the food service sector, with significant ecological and economical impacts. In order to understand and explain better the complex issue of food waste a qualitative study was conducted on the reasons for its generation in restaurants and catering businesses. Research data were collected during three participatory workshops for personnel from three different catering sector companies in Finland. Based on synthesized qualitative content analysis, eight elements influencing production and reduction of food waste were identified. Results revealed the diversity of managing food waste in the food service sector and how a holistic approach is required to prevent and reduce it. It is crucial to understand that food waste is manageable and should be an integral component of the management system. The model of eight factors provides a framework for recognition and management of food waste in the food service sector.

Effects of varying the ratio of cooked to uncooked potato on the microbial fuel cell treatment of common potato waste.

The effect of varying the ratio of cooked to uncooked potato in the performance of microbial fuel cell (MFC) treating common potato waste was investigated. Four MFCs were fed with a ratio of cooked (boiled) to uncooked (i.e. waste) potato of 0, 48.7, 67.3 and 85.6%. Respectively, the columbic efficiency was estimated as 53.5, 70.5, 92.7 and 71.1%, indicating significantly enhanced electricity generation and waste degradation at an initial feedstock mixing ratio of 2/3 cooked to 1/3 uncooked potato. The hydrolysis rate parameter (estimated using a first-order sequential hydrolysis and degradation model) increased from 0.061 to 0.191day(-1) as cooked potato was added which increased electricity generation efficiency from 24.6 to 278.9mA/m(2)/d and shortened the startup time for maximum current density from 25 to 5days. The potato slurries' chemical oxygen demand (COD) decreased by 86.6, 83.9, 84.1 and 86.3%, respectively, indicating no relationship exists between the fraction of boiled potato and the amount of COD reduction.

Recycle food wastes into high quality fish feeds for safe and quality fish production.

The amount of food waste generated from modern societies is increasing, which has imposed a tremendous pressure on its treatment and disposal. Food waste should be treated as a valuable resource rather than waste, and turning it into fish feeds would be a viable alternative. This paper attempts to review the feasibility of using food waste to formulate feed pellets to culture a few freshwater fish species, such as grass carp, grey mullet, and tilapia, under polyculture mode (growing different species in the same pond). These species occupy different ecological niches, with different feeding modes (i.e., herbivorous, filter feeding, etc.), and therefore all the nutrients derived from the food waste could be efficiently recycled within the ecosystem. The problems facing environmental pollution and fish contamination; the past and present situation of inland fish culture (focusing on South China); upgrade of food waste based feed pellets by adding enzymes, vitamin-mineral premix, probiotics (yeast), prebiotics, and Chinese medicinal herbs into feeds; and potential health risks of fish cultivated by food waste based pellets are discussed, citing some local examples. It can be concluded that appropriate portions of different types of food waste could satisfy basic nutritional requirements of lower trophic level fish species such as grass carp and tilapia. Upgrading the fish pellets by adding different supplements mentioned above could further elevated the quality of feeds, leading to higher growth rates, and enhanced immunity of fish. Health risk assessments based on the major environmental contaminants (mercury, PAHs and DDTs) in fish flesh showed that fish fed food waste based pellets are safer for consumption, when compared with those fed commercial feed pellets.

Co-treatment of fruit and vegetable waste in sludge digesters: Chemical and spectroscopic investigation by fluorescence and Fourier transform infrared spectroscopy.

In a previous work co-digestion of food waste and sewage sludge was performed in a pilot apparatus reproducing operating conditions of an existing full scale digester and processing waste mixed sludge (WMS) and fruit and vegetable waste (FVW) at different organic loading rates. An analysis of the relationship among bio-methane generation, process stability and digestate phytotoxicity was conducted. In this paper we considered humification parameters and spectroscopic analysis. Humification parameters indicated a higher not humified fraction (NH) and a lower degree of humification (DH) of FVW with respect to WMS (NH=19.22 and 5.10%; DH=36.65 and 61.94% for FVW and WMS, respectively) associated with their different chemical compositions and with the stabilization process previously undergone by sludge. FVW additions seemed to be favourable from an agronomical point of view since a lower percentage of organic carbon was lost. Fourier transform infrared spectra suggested consumption of aliphatics associated with rising in bio-methane generation followed by accumulation of aliphatics and carboxylic acids when the biogas production dropped. The trend of peaks ratios can be used as an indicator of the process efficiency. Fluorescence intensity of peak B associated with tryptophan-like substances and peak D associated with humic-like substances observed on tridimensional Excitation Emission Matrix maps increased up to sample corresponding to the highest rate of biogas production. Overall spectroscopic results provided evidence of different chemical pathways of anaerobic digestion associated with increasing amount of FVW which led to different levels of biogas production.

Simultaneous production of l-lactic acid with high optical activity and a soil amendment with food waste that demonstrates plant growth promoting activity.

A unique method to produce highly optically-active l-lactic acid and soil amendments that promote plant growth from food waste was proposed. Three Bacillus strains Bacillus subtilis KBKU21, B. subtilis N3-9 and Bacillus coagulans T27, were used. Strain KBKU21 accumulated 36.9 g/L l-lactic acid with 95.7% optical activity and 98.2% l-lactic acid selectivity when fermented at 43°C for 84 h in a model kitchen refuse (MKR) medium. Residual precipitate fraction (anaerobically-fermented MKR (AFM) compost) analysis revealed 4.60%, 0.70% and 0.75% of nitrogen (as N), phosphorous (as P2O5), and potassium (as K2O), respectively. Additionally, the carbon to nitrogen ratio decreased from 13.3 to 10.6. AFM compost with KBKU21 promoted plant growth parameters, including leaf length, plant height and fresh weight of Brassica rapa (Komatsuna), than that by chemical fertilizers or commercial compost. The concept provides an incentive for the complete recycling of food waste, contributing towards a sustainable production system.