Characteristics of Starch Extracted from the Stem of Pineapple Plant (Ananas comosus) - an Agro Waste from Pineapple Farms

Abstract The present study focused on the use of pineapple plant stem, which is an agro-waste, for the production of starch (11.08 % ± 0.77). Characters were studied using X-ray diffraction, nuclear magnetic resonance spectroscopy (NMR), fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and rheological methods. The granular size of stem starch was comparatively smaller than corn starch granules. The X-ray diffraction data revealed that stem starch has an A-type crystal structure. The molecular structure was similar to those obtained for native starches, which is confirmed by NMR and FTIR. The gelatinization temperature was observed to be higher than corn starch and rheological studies revealed; stem starch is more viscous than corn starch. The purity analysis showed that the harmful heavy metals were in negligible quantity and the tested pesticides were absent. This could make this a good source of starch for food industries. Results revealed that this agro-waste has a high potential for the production of good quality starch.

Agro-food waste employed to design and develop culture media for fungal growth

Aim: Waste from the agricultural and food industries could be used as a source of nutrients in the culture media for fungal growth and thus reduce environmental pollution and the cost of bioprocesses. In this work, it was determined if some agro-food waste can improve the mycelial growth of fungi and laccase production.Methodology: Culture media with agar and vermicompost, vermiwash, calcined pork bones or fish waste for mycelial growth of fungi were elaborated. The laccase activity of each strain grown in all culture media was also estimated. Results: Pleurotus eryngii, Lentinula edodes, Pleurotus ostreatus, Flammulina velutipes, Pleurotus citrinopileatus and Ganoderma lucidum grew in all culture media, except Lentinula edodes, obtaining in general higher biomass and radial growth rate than those observed on potato-dextrose agar. The maximum laccase activity was found in Pleurotus citrinopileatus cultivated in fish waste medium. The C: N ratio, ashes and pH were important factors for the growth of the strains. Interpretation: There were significant differences in biomass concentration and laccase activity in the designed culture media. These results provide an interesting alternative for the use of wastes and metabolites production of industrial interest.

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.

Comparative study of the hypocholesterolemic, antidiabetic effects of four agro-waste Citrus peels cultivars and their HPLC standardization

ABSTRACT Citrus is an economically important fruit for Egypt, but its peel also is one of the major sources of agricultural waste. Due to its fermentation, this waste causes many economic and environmental problems. Therefore it is worthwhile to investigate ways to make use of this citrus waste generated by the juice industry. This study was aimed to explore the hypocholesterolemic, antidiabetic activities of four varieties of citrus peels agrowastes, to isolate the main flavonoids in the active fractions and to quantify them by HPLC method for nutraceutical purposes. All the tested samples of the agro-waste Citrus fruits peels showed significant decrease in cholesterol, triacylglyceride and glucose. The most decrease in cholesterol level was observed by mandarin peels aqueous homogenate and its hexane fraction (59.3% and 56.8%, respectively) reaching the same effect as the reference drug used (54.7%). Mostly, all samples decrease triacylglyceride (by 36%-80.6%) better than the reference drug used (by 35%), while, glucose was decreased (by 71.1%-82.8 and 68.6%-79.6%, respectively) mostly by the aqueous homogenates (except lime) and alcoholic extracts (except mandarin) of Citrus fruits peels better than the reference drug used (by 68.3%). All the isolated pectin, from the four cultivars, has significant effect on the three parameters. The comparative HPLC rapid quantification of nobiletin in the different by-product citrus varieties hexane fractions revealed that nobiletin is present in higher concentration in mandarin (10.14%) than the other species. Nobiletin and 4′,5,7,8-tetramethoxy flavone were isolated from mandarin peels hexane fraction by chromatographic fractionation. This is the first report of the comparative HPLC quantification of nobiletin and biological studies of different citrus peels species as agro-waste products. Based on these results, we suggest the possibility that Citrus fruits peels may be considered as an antidiabetic and hypocholesterolemic nutraceutical product.

Production of flavor compounds from olive mill waste by Rhizopus oryzae and Candida tropicalis

Abstract The purpose of this study was to investigate the production of flavor compounds from olive mill waste by microbial fermentation of Rhizopus oryzae and Candida tropicalis. Olive mill waste fermentations were performed in shake and bioreactor cultures. Production of flavor compounds from olive mill waste was followed by Gas Chromatography–Mass spectrometry, Gas chromatography- olfactometry and Spectrum Sensory Analysis ®. As a result, 1.73-log and 3.23-log cfu/mL increases were observed in the microbial populations of R. oryzae and C. tropicalis during shake cultures, respectively. C. tropicalis can produce a higher concentration of d-limonene from olive mill waste than R. oryzae in shake cultures. The concentration of d-limonene was determined as 185.56 and 249.54 µg/kg in the fermented olive mill waste by R. oryzae and C. tropicalis in shake cultures respectively. In contrast, R. oryzae can produce a higher concentration of d-limonene (87.73 µg/kg) d-limonene than C. tropicalis (11.95 µg/kg) in bioreactor cultures. Based on sensory analysis, unripe olive, wet towel, sweet aromatic, fermented aromas were determined at high intensity in olive mill waste fermented with R. oryzae meanwhile olive mill waste fermented with C. tropicalis had only a high intensity of unripe olive and oily aroma.

Partial Purification and Characterization of β-glucosidase from Monascus sanguineus

The aim of the present work was to study the production and characterization of β-glucosidase from Monascus sanguineus. Agro-waste residues were screened to obtain the maximum yield of enzyme. Jack fruit seed was the best substrate for enzyme production. Studies on the optimization of pH and temperature showed acidic pH favorable for enzymatic activity, whereas the optimum temperature was 60°C. Enzyme kinetics studies with different concentration of pNPG showed the calculated value of Km approximately 0.89 mM with the non-linear regression and 0.98 mM with the linear regression techniques. The enzyme was predominantly inhibited by KCl (69.8%) and moderately inhibited by CaCl2 (14.8%). Studies on the sensitivity for glucose showed that after 100 mM concentration of glucose, inhibition in pNPG hydrolysis took place. The molecular weight of the protein was estimated as 116 and 66 kDa with SDS- PAGE and zymography was carried out to verify the specific activity.