Microbiological Quality of Water from Lis Valley Rice Ecosystems

A cultura do arroz tem um importante valor económico e social em Portugal, numa área total de cerca de 30 mil ha. Os agroecossistemas orizícolas são peculiares, desenvolvem-se em terrenos baixos, planos e aluvionares, na proximidade da costa, com uma natural dificuldade de drenagem e influência da salinidade, com o cultivo em canteiros regados por submersão contínua, num equilíbrio muito sensível. Os sistemas orizícolas desempenham um valioso papel ambiental, em harmonia com a produção de um alimento humano de reconhecida qualidade, num contributo significativo para a soberania alimentar nacional. Os principais constrangimentos atuais da rega do arroz prendem-se com a escassez de água, questões com uma dimensão mundial, sendo a poupança de água um tema muito estudado, com diversas soluções alternativas já implementadas na realidade de vários países. Este estudo teve como objetivo analisar a qualidade microbiológica da água e do solo no cultivo de arroz no Vale do Lis em sistemas de rega por submersão contínua e intermitente em canteiros de nível, e na rega por gotejamento num talhão de ensaio, para avaliar os respetivos impactos nos recursos hídricos, visando contribuir para o estabelecimento de boas práticas agrícolas e de saúde pública e ambiental no uso da água e do solo naqueles agroecossistemas. Na metodologia experimental foram selecionados os bioindicadores microbiológicos clássicos de contaminação fecal (coliformes totais, coliformes fecais e enterecocos fecais), bem como uma análise de resistência a antibióticos (enumeração de Enterobacteriaceae resistentes à ampicilina, caracterização fenotípica de bactérias resistentes isoladas e deteção molecular de seus genes de resistência a antibióticos. Os resultados dos bioindicadores clássicos nos sistemas de alagamento apontam para um impacte ambiental positivo, pois a água drenada tem melhor qualidade do que a água utilizada na rega. Por outro lado, estes arrozais apresentam indícios de poluição por fauna selvagem, o que reforça o serviço ambiental desempenhado por esses agroecossistemas, pois fornecem habitat e alimento para diversas espécies deste tipo. Em relação à análise de resistência aos antibióticos, os resultados indicam que a enumeração de Enterobacteriaceae resistentes à ampicilina permanece idêntica ou aumenta nas saídas de água, em comparação com as entradas, que os fenótipos de resistência a antibióticos testados estão amplamente disseminados nesses agroecossistemas e também são altamente prevalentes em amostras colhidas tanto nas entradas quanto nas saídas, com alta percentagem de isolados multirresistentes, e que a identificação de genes tet e sul revelou a prevalência de tetA, tetL, tetM e sul2. Como conclusão, em relação aos bioindicadores fecais, os sistemas de produção de arroz por alagamento têm um efeito depurador significativo na qualidade da água, contribuindo para a melhoria da qualidade da água de drenagem da rede coletiva. No entanto, a análise de resistência a antibióticos revelou que a saúde do agricultor e os ecossistemas de arroz podem estar ameaçados, pois esses ambientes atuam como um hotspot para a disseminação de determinantes genéticos de antibióticos. Propõe-se que os planos de gestão da água no aproveitamento hidroagrícola incluam a monitorização da qualidade da água de rega, com uma frequência de amostragem de acordo com as fontes de poluição, para estabelecer cuidados especiais de higiene e segurança.Rice cultivation has an important economic and social value in Portugal, covering a total area of about 30 thousand ha. Rice agroecosystems are peculiar. They are located in low, flat and alluvial lands, close to the coast, with a natural difficulty in drainage and a salinity influence, with cultivation in level basins, irrigated by continuous submersion, in a very sensitive balance. Rice farming systems play a valuable environmental role, in harmony with the production of a human food of recognized quality, in a significant contribution to national food sovereignty. The main current constraints of rice irrigation are related to water scarcity, issues with a global dimension, with water saving being a much studied topic, with several alternative solutions already implemented in several countries. This study aimed to analyse the microbiological quality of water and soil in rice cultivation in Vale do Lis with irrigation systems by continuous and intermittent submersion in level basins, and in drip irrigation, to evaluate the respective impacts on water resources, aiming to contribute to the establishment of good agricultural practices and public and environmental health regarding the use of water and soil in those agroecosystems. In the experimental methodology, the classic microbiological bioindicators of fecal contamination (total coliforms, fecal coliforms and fecal enterococci) were selected, as well as an analysis of antibiotic resistance (enumeration of ampicillin-resistant Enterobacteriaceae, phenotypic characterization of isolated resistant bacteria and molecular detection of their antibiotic resistance genes. The results of the classic bioindicators in flooding systems point to a positive environmental impact, as the drained water has better quality than the water used for irrigation. On the other hand, these rice paddies show signs of pollution by wild fauna , which reinforces the environmental service performed by these agroecosystems, as they provide habitat and food for several species of this type. Regarding the analysis of antibiotic resistance, the results indicate that the enumeration of ampicillin-resistant Enterobacteriaceae remains identical or increases in the water outlets, compared to the entrances, that the antibiotic resistance phenotypes tested are widely disseminated in these agroecosystems and are also highly prevalent in samples collected both at the entrances and at the exits, with a high percentage of multidrug-resistant isolates, and that the identification of tet and sul genes revealed the prevalence of tetA, tetL, tetM and sul2. In conclusion, in relation to fecal bioindicators, rice production systems by flooding have a significant purifying effect on water quality, contributing to improving the quality of drainage water from the collective network. However, antibiotic resistance analysis revealed that farmer health and rice ecosystems may be threatened as these environments act as a hotspot for the spread of genetic determinants of antibiotics. It is proposed that water management plans in hydro-agricultural development include monitoring the quality of irrigation water, with a sampling frequency according to the sources of pollution, to establish special hygiene and safety precautions

Pharmacognostic evaluation of Bilva [Aegle marmelos (L.) Correa] root bark

670-676Aegle marmelos L., family Rutaceae, is a sacred plant mentioned in various Hindu scriptures. It has both medicinal as well as cultural importance. In the present investigation, macroscopy, microscopy, and powder microscopy studies, physicochemical analysis, detection of heavy metals, analysis of aflatoxins, screening of microbiological parameters and High Performance Thin Layer Chromatography (HPTLC) fingerprint profile of methanolic extract were performed. Analysis of 04 aflatoxins (A1, B1, A2, and B2) was performed and found that no aflatoxins were present, authenticated by comparing the Rf value and colour of the standards spot with sample on TLC plate. Qualitative microbiological analysis of pathogenic bacteria, i.e., Staphylococcus aureus, Salmonella sp., Pseudomonasaeruginosa and Escherichia coli were done and found that no bacterial pathogens are present in the Aegle marmelos root bark extract. HPTLC chromatographic fingerprint of Aegle marmelos root bark was done by using mobile phase toluene: ethyl acetate: formic acid (7.5: 2.5: 0.4). TLC plate was derivatized by using derivatizing reagent 5% Methanolic - sulphuric acid reagent and plate was heated at 105°C till the bands are clearly visible. Major spots Rf values and colour were noted at 254 nm, 366 nm, after derivatization 366 nm and UV light. Therefore, established parameters may be used as a reference tool for proper recognition and confirmation of right plant material and monitoring of batch to batch consistency of finished herbal products using Aegle marmelos as an ingredient. This study may also helpful in the preparation of Aegle marmelos root bark monograph

Thiamine, Riboflavin, and Sensory Stability of Irradiated Brown Rice.

While brown rice is nutritionally superior to white rice, it is not shelf stable, becoming rancid in a matter of weeks. Preservation by refrigeration or freezing is expensive and not universally available. Therefore, other preservation methods, such as aqueous ethanol extraction of lipids, have been studied to overcome this problem, but these methods also have limitations. The effects of gamma-irradiation on the physicochemical properties and lipase activity in brown rice has been well documented. Gamma-irradiation has been shown to reduce lipase activity, presumably preserving sensory quality. A sensory study of 2 Louisiana grown varieties (Mars and Lemont) of irradiated brown rice performed at monthly intervals over a period of 6 months was conducted to provide the definitive data to assess this method of preservation for sensory effects. Rough rice was de-hulled, irradiated at 0, 1, and 2 kGy, and stored for a period of up to 6 months at ambient temperature in sealed plastic bags. Duplicate samples were taken at monthly intervals starting with time 0 and evaluated for thiamine and riboflavin status using reverse phase HPLC and sensory quality using an experienced 8-person panel, respectively. These procedures were replicated 3 times to ensure scientific and statistical validity. The 2 kGy treatment level produced the worst hedonic rating for both varieties. The 1 kGy radiation level did not significantly affect the sensory quality of either rice variety. Storage negatively affected nutty and milky attributes, which were stable to irradiation treatment. The rancidity attribute of brown rice samples, as perceived by the sensory panel, was negatively affected by irradiation treatment. The effect of treatment and storage on thiamine and riboflavin levels of the rice samples was significantly different from the control only at the 2 kGy level Mars variety at 6 months of storage. However, treated samples of the Mars variety stored for a period of 6 months retained nearly 50% of original thiamine and riboflavin levels. Thiamine and riboflavin were essentially unaffected by storage or treatment in Lemont rice samples

FORMULATION AND EVALUATION OF AN ANTIMICROBIAL MUCOADHESIVE DENTAL GEL OF AZADIRACHTA INDICA AND GLYCYRRHIZA GLABRA

Objective: Objective of this study was to formulate and evaluate an antimicrobial mucoadhesive dental gel of herbal drugs for the prevention and treatment of dental plaque, dental caries, and periodontitis. Methods: Azadirachta indica leaves extract was prepared with ethanol: water (80:20 v/v) and Glycyrrhiza glabra roots extract was prepared with ethanol: water (30:70 v/v). Both the extracts were evaluated for organoleptic properties, pH, phytochemical screening and total phenolic content. Thin layer chromatography (TLC) and Reverse-phase high-performance liquid chromatography (RP-HPLC) studies were performed. Antibacterial activity of the extract was done on Mueller Hinton agar media against Streptococcus mutans using the disc diffusion method. A mucoadhesive gel was prepared using carbopol 934, polyethylene glycol (PEG) 400 as a bioadhesive polymer and penetration enhancer, respectively. Three gel formulations were prepared at various concentrations of carbopol 934. Dental gel formulations were evaluated for different parameters such as appearance, pH, viscosity, spreadabilty, syringeability. Optimised batch was used for further studies viz. stability study, drug content, diffusion study to determine percent cumulative release of drug from gel formulation and in vitro mucoadhesion study. Results: Rf value of nimbin and glycyrrhizin in TLC study, were found to be 0.08 and 0.56, respectively. RP-HPLC method was developed for estimation of active constituents present in both extracts using mobile phase acetonitrile: water [containing 0.1 % v/v glacial Acetic acid (GAA)]: methanol in the ratio of 30:60:10 at the flow rate of 0.8 ml/min. Rt of active constituents from both drug extracts was found to be 3.119 and 4.15 min, respectively. 2.5 % w/v of Azadirachta indica leaves extract showed a good zone of inhibition (10.66±0.577 mm) near to chlorhexidine (11.33±0.5773 mm). 1 % of Glycyrrhiza glabra roots extract exhibit antibacterial activity (9±1 mm) and masks the bitter taste of formulation. Batch (F2) was selected on the basis of viscosity, spreadabilty and syringeability. The optimised batch was found to be stable and has 83 % and 80.3 % of drug content. Percent cumulative releases of the drug from gel formulation during the diffusion study were found to be 87.52 % and 85.43 %. Adhesive force and adhesiveness were found to be 11.90 g and 0.92 millijoule, respectively during mucoadhesion study. Conclusion: The evaluation parameters of optimized batch indicate the prepared dental gel is mucoadhesive, stable, good delivery drug system containing antimicrobial agents for prevention of plaque formation, dental caries and periodontitis

Design and evaluation of fast dispersible tablets of lamivudine using selected natural superdisintegrants

Magister Pharmaceuticae - MPharmFast dispersible tablets (FDTs) are solid single-unit dosage forms that are placed in the mouth and allowed to disperse or dissolve in the saliva without the need of water. The basic approach to formulating FDTs consists of adding a superdisintegrant to a tablet formulation. These tablets offer both the advantages of conventional tablets and liquid dosage forms along with distinctive properties which include accurate dosing, ease of administration, quick onset of action, enhanced bioavailability, and increased patient adherence. FDTs have been found to be effective in remedying therapeutic in-adherence caused by dysphagia (swallowing difficulties) particularly in paediatric and geriatric subjects. There is a strong correlation between therapeutic success and patient adherence especially with HIV/AIDS treatment regimens, consequently the dosage form should be patient friendly and devoid of unappealing characteristics. This study aimed at developing a cost effective fast dispersible tablet of lamivudine using alternative excipients and conventional techniques. Only conventional tablets and oral liquid dosage forms of lamivudine are available on the South African market. Two natural polymers reported to have superdisintegrating properties were selected to serve as multipurpose excipients in this study. The polymers were identified, characterised and compared using thermal, spectroscopic and micromeritic analytical tools. The polymer that displayed the best characteristics in terms of micromeritic, tableting and disintegrating properties was retained and used for the optimum formulation. The optimum formulation was composed of 150 mg of lamivudine, 23% w/w unripe banana powder and 2% w/w magnesium stearate. FDTs of lamivudine were obtained using the compression technique with and without wet granulation. The tablets were assessed as per the United States Pharmacopoeia (USP) guidelines and other evaluation procedures pertaining to FDTs. The wet granulated tablets were found to be less friable and thus more resilient than the directly compressed tablets. In-vitro disintegration of the wet granulated tablets occurred within 50±3 sec in deionised water (pH 7) and 35±2 sec in a phosphate buffer solution (pH 6.8). Consequently, the innovative tablets fulfilled the core requirement of FDTs i.e. rapid disintegration. Drug release studies were carried out by analysing dissolution aliquots of the innovative tablets using a validated High Performance Liquid Chromatography (HPLC) method, and comparing them to Aspen Lamivudine®, a conventional tablet of lamivudine presently on the South African market. Complete dissolution in deionised water (pH 7) was attained within 10 minutes and 30 minutes for the innovative tablets and Aspen Lamivudine® respectively

Preparation and characterization of licorice‐chitosan coatings for postharvest treatment of fresh strawberries

Several plant extracts are being investigated to produce edible coatings, mainly due to their antioxidant and antimicrobial activities. In this study, licorice root extracts were produced by ultrasound‐assisted extraction and were combined with chitosan to elaborate edible coatings. Different solvents and temperatures were used in the extraction process, and the antioxidant and antimicrobial activity of the extracts were assessed. The most bioactive extracts were selected for the development of the edible coatings. The rheological properties of the coatings were studied, and they were applied on strawberry to evaluate their physicochemical and microbiological properties. The addition of licorice extract to chitosan resulted in positive effects on the rheological properties of the coatings: the incorporation of phytochemicals to chitosan decreased the shear stress and improved the restructuring ability of the coating solutions. The films presented a reduction of the Burger model parameter, indicating a reduction of rigidity. Furthermore, the strawberry coated with chitosan and licorice extract maintained good quality parameters during storage and showed the best microbiological preservation in comparison with controls. Hence, the use of chitosan with licorice extract is a potential strategy to produce edible coating for improving the postharvest quality of fruitsThis research was funded by Comunidad Autónoma de Madrid, grant number P2013/ABI27, project Bolívar Gana con Ciencia, MinCiencias Contract 368-2019 and Programa Nacional de Innovación Agraria—PNIA of Perú, Contract: No. 152-2018-INIA-PNIA-PASANTI

Compost and digestate: sustainability, benefits, impacts for the environment and for plant production

This proceedings volume contains the papers presented at the CODIS 2008 congress held on 27 - 29 February 2008 in Solothurn (Switzerland).The composting and digestion of biogenic waste materials and the subsequent application of compost and digestate to soil contributes to nutrient recycling and renewable energy production. Moreover, compost and digestate can improve soil fertility and suppress plant diseases. On the other hand, compost and digestate may also contain a variety of pollutants hazardous to soil, such as heavy metals and organic contaminants.Compost and digestate have been thoroughly investigated in the framework of two associated projects entitled Organic Pollutants in Compost and Digestate in Switzerland and Effects of Composts and Digestate on the Environment, Soil Fertility and Plant Health. These projects yielded new insights into the properties of compost and digestate, mainly with regard to biological parameters and the occurrence of both classic and emerging organic pollutants.The CODIS 2008 congress was the final event of these two projects

Monitoring tomato leaf disease through convolutional neural networks

Agriculture plays an essential role in Mexico’s economy. The agricultural sector has a 2.5% share of Mexico’s gross domestic product. Specifically, tomatoes have become the country’s most exported agricultural product. That is why there is an increasing need to improve crop yields. One of the elements that can considerably affect crop productivity is diseases caused by agents such as bacteria, fungi, and viruses. However, the process of disease identification can be costly and, in many cases, time-consuming. Deep learning techniques have begun to be applied in the process of plant disease identification with promising results. In this paper, we propose a model based on convolutional neural networks to identify and classify tomato leaf diseases using a public dataset and complementing it with other photographs taken in the fields of the country. To avoid overfitting, generative adversarial networks were used to generate samples with the same characteristics as the training data. The results show that the proposed model achieves a high performance in the process of detection and classification of diseases in tomato leaves: the accuracy achieved is greater than 99% in both the training dataset and the test dataset.This work was partially funded by the State Research Agency of Spain under grant number PID2020-116377RB-C21.Peer ReviewedPostprint (published version