الفهرس 
1. INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
6. SUMMARY
Olive production is considered as an important national income source for most Mediterranean countries as it is nearly totally produced in the Mediterranean basin. The main production is being processed industrially to produce olive oil, and this industry is facing a worldwide major post-production obstacle: it is the management of olive mill waste (OMW). The OMW is a toxic waste that has unfavorable environmental effects, so it needs a management process for detoxification. The high organic and phenols content of OMW causes an intense problem in the environment, thus strong restrictions emerged refuses dumping agricultural wastes into city sewers or water such as rivers and uncontrolled reservoirs. Consequently, a purification process is severely needed to remove the danger effects of its crude form. So, the main object of the present work is to biodegrade the phenols content of olive mill solid waste (OMSW) by a locally isolated fungus under optimized culture conditions and study the effect of the fermented OMSW as a fertilizer on some growth and physiological parameters of Vicia fabaL. The results obtained are summarized in the following points:
• The work was started by isolating fungi from garden soil and from OMSW. Ten fungal isolates were purified using single spore isolation and identified as five species of Aspergillus, four species of Penicillium and one species of Fusarium.
• The efficiency of the tested fungi to degrade phenols content of OMSW (845.5mg/100g) indicated that A.tamarii was the most active fungus that can degrade OMSW phenols (64.07%) as compared to the other tested fungi.
• To specify the best ingredients of the culture medium that favored the formation and activation of enzyme system responsible for hydrolysis of OMSW phenols, six different media of mineral salts were tested. The results indicated that formulation of medium (III) of the composition (g/l): K2HPO4, 3.40 ; KH2PO4, 4.30 ; MgSO4.7H2O, 0.30 ; (NH4)2SO4, 1.0 ; yeast extract, 0.05 ; 10 ml of trace elements solution (mg/l) of MnCl.4H2O, 1.0 ; FeSO4.7H2O, 0.6 ; CaCl2.H2O, 2.6 ; Na2MoO4.2H2O, 6, that has a yeast extract as additional nitrogen source beside (NH4)2SO4 and trace elements solutionfortifiedA.tamarii by nutrients, qualitatively and quantitatively, in favor the formation of highly active phenols degrade enzymes.
• To certify the best fermentation period at which A.tamarii can degrade phenols content of OMSW, time course study of phenols degradation was followed out through nine days of fermentation under the best fermentation conditions. The results indicated that the highest phenols degradation (84.6%) and the high biodegraded phenols per day (102.18mg/day) were achieved after 168h. (7days) of fermentations.
• To optimize the culture conditions for maximum degradation of phenols; two approaches of statistical designs had been conducted. The first deals with evaluating the different medium constituents and some cultural conditions using the Plackett-Burman design, and the second was to optimize the most important factors that significantly affected the degradation process using response surface methodology (RSM) of Box-Behnken.
• The data of screening of important variables using Plackett-Burman design indicated a wide variation in phenols degradation, from 25.75 to 94.5%, in the 14 trials. Analysis of the regression coefficients and the t-value of 11-factors tested showed that the most significant three factors in phenols degradation were medium volume/flask (aeration), Na2MoO4.2H2O, and (NH4)2SO4. The predicted medium composition and culture conditions to be near optimum, which resulted from application of Plackett-Burman statistical design was (g/l): OMSW, 80 ; K2HPO4, 3.40 ; KH2PO4, 4.30 ; MgSO4.7H2O, 0.30 ; (NH4)2SO4, 1.0 ; yeast extract, 0.05 ; MnCl.4H2O, 10 (µg) ; FeSO4.7H2O, 6 (µg) ; CaCl2.H2O, 26 (µg) ; Na2MoO4.2H2O, 100 (µg), and medium volume/flask, 25 ml ; pH 6. Inoculated with 3 ml of spore suspension (6x106 spores/ml) and incubated under shake (180 rpm) for 7 days at 30o±2oC.
• A confirmatory experiment was conducted to verify the predicted Plackett-Burman conditions in comparison to its reverse conditions and basal medium. The results revealed that 96.28% phenols degradation by A.tamarii was with the predicted Plackett-Burman conditions that about 13.8% than basal medium and 2.3 fold increase than the reverse conditions. So, the results indicate the validity and efficiency of Plackett-Burman design.
• In order to approach the optimum response region of phenols degradation, significant independent variables (medium volume/flask, (NH4)2SO4 and Na2MoO4.2H2O) were further explored by applying RSM, each at three levels. The results indicated that the optimal levels of the three examined independent variables as predicted from the model, were (NH4)2SO4, 0.5 g/l ;Na2MoO4.2H2O, 150 µg/l, and medium volume 25 ml/flask. Under these conditions, 100% phenols degradation after 7 days (168h) of fermentation was recorded. Therefore, the degradation percentage of about 8.46g/kgof OMSW phenols increased from 84.61% in the basal into 96.28% after optimization of Plackett-Burman to 100% after RSM, and 100% phenols were degraded after only 158h of fermentation instead of 168h.
• These results of proximate chemical analysis of the fermented OMSW supported its use as a fertilizer were its pH tend to neutrally and complete absence of the phytotoxic phenols content as well as its reduced lipid content. The affiliated aim in the current laboratory-scale study is to assess the effect of OMSW; residue of water extracted and fermented OMSW on some growth and physiological parameters in order to determine the most appropriate waste to increase soil fertility.
• The application of olive-mill waste aqueous extract (OMSWAE) to the 24h germinating Vicia faba L. (broad bean) seeds exhibited a severe reduction to plumule (PL) and radicle (RL) lengths in accordance with the increase in extract concentrations.
• The use of olive mill solid waste (OMSW) has been seen to have a detrimental effect on broad bean growth. Increasing of OMSW concentrations (2, 4, 8, and 16%) resulted in a marked reduction of length, fresh and dry weights of shoots and roots. This was accompanied with a notable decline of chlorophylls content, chlorophyll stability index (CSI), the efficiency of PSII (Fv/Fm), total available carbohydrates (TAC), total proteins (TP) and the macro elements K, P, Mg and Ca contents.
• Application of the residue of water extracted (ROMSW) and A.tamarii-fermented (FOMSW) olive mill waste to the soil, improved the growth, chlorophyll contents, CSI, chlorophyll a fluorescence (Fv/Fm), TAC, TP and macronutrient concentrations. This improvement was increased with increasing concentrations of ROMSW, while it increased up to 4% of FOMSW then gradually declined.
• There was a marked increase of carotenoids and total phenolics contents with increasing the waste level (OMSW, ROMSW and FOMSW) in the soil.
• It was shown that washing- and A.tamarri-treatment waste resulted in increase the pH from 5.1 to 6.8 and 7, respectively, and decrease total phenolics from 8.46g/kg to 2.5g/kg and 0.0g/kg waste, respectively. Consequently, the improvement of soil characteristics, due to washing- or A.tamarii- treatment of waste.
• There was a marked increase of broad bean growth in A.tamarii - fermented waste and the growth decreased in high concentrations this accompanied with a significant increase of phenolics content in broad bean shoots.
• Finally, the study confirmed that OMSW detoxification (water or microbiologically) might result in a marked reduction of phenolics and rising in pH which allows a safe and economical disposal of OMSW, and the using A.tamarii as a bio-degradable for OMSW exhibitedthe complete absence of the phytotoxic action of phenols that lead to positive effects of detoxified OMSW.So, itcan be satisfactory act as bio-organic fertilizers that improve soil characteristics and hence the plant growth.