Formic acid as an antibiotic alternative in broiler diets: effects on growth, carcass characteristics, blood chemistry, and intestinal microbial load.

This study explored the ability of formic acid (FA) to replace antibiotics in broiler chicken diets. It examined how FA affected the chickens' growth, carcass characteristics, blood chemistry, and gut bacteria. The experiment randomly assigned 300 one-day-old (Ross 308) broiler chicks to 5 groups, each divided into 6 replicates with 10 unsexed chicks. The following were the treatments: 1st group, negative control (NC): only received a basal diet; 2nd group, positive control (PC): received a basal diet supplemented with 0.5 grams of Colistin antibiotic per kilogram of diet; 3rd, 4th, and 5th groups (FA2, FA4, and FA6) these groups received a basal diet along with formic acid added at increasing levels: 2, 4, and 6 Cm3 per kilogram of diet, respectively. Results found no significant differences in live body weight (LBW) or body weight gain (BWG) between treatment groups, except for LBW at one week and BWG at 0 to 1 and 4 to 5 wk of age. No significant variations were found in feed intake (FI) and feed conversion ratio (FCR) among the treatment groups, excluding FI and FCR at 1 to 2 wk of age. The treatments significantly impacted carcass traits, dressing percentage, breast meat, thigh meat, spleen, giblets, blood levels of urea, creatinine, total protein, globulin, and albumin, as well as the activity of enzymes alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in chicks fed different diets compared to control groups. The addition of FA to the diet significantly impacted antioxidant levels. Also, the FA2 group had the highest total bacterial count (TBC). However, the FA6 group was the opposite; it had the lowest levels of harmful bacteria, such as E. coli and Coliform. Supplementing broiler diets with formic acid improves blood parameters, antioxidant activity, and gut bacteria counts, with 4.0 cm³ formic acid/kg diet supplementation promoting optimal broiler health and product quality.

Ethoxyquin attenuates enteric oxidative stress and inflammation by promoting cytokine expressions and symbiotic microbiota in heat-stressed broilers.

Intestinal oxidative stress in broilers is produced by chronic heat stress (HS) and has a negative impact on poultry performance as it induces intestinal inflammation and promotes the invasion of gram-negative bacteria, such as bacterial lipopolysaccharide (LPS). Therefore, dietary inclusion of the antioxidant compound, ethoxyquin (EQ), could improve enteric antioxidant capacity, immune responses, and the epithelial barrier, and maintain the symbiotic gut microbiota community. To investigate the effects of EQ supplementation on alleviating enteric oxidative stress in heat-stressed broilers, 200 one-day-old male Ross 308 broilers were randomly assigned to 4 groups (n = 50 chicks/group; n = 10 chicks/replicate) and fed a basal diet supplemented with 0 (CT), 50 (EQ-50), 100 (EQ-100), and 200 (EQ-200) mg EQ/ kg-1 for 5 wk. The chicks were raised in floor pens inside the broiler farm at a temperature and humidity index (THI) of 29 from d 21 to d 35. Growth performance traits, relative organ index, hepatic antioxidant enzymes, serum immunity, total adenylate, and cytokine activities were improved in the EQ-50 group (linear or quadratic P < 0.05), promoting the relative mRNA expression of cytokine gene-related anti-inflammatory and growth factors. A distinct microbial community colonised the gut microbiota in the EQ-50 group, with a high relative abundance of Lactobacillus, Ligilactobacillus, Limosilactobacillus, Pediococcus, Blautia, and Faecalibacterium compared to the other groups. Dietary supplementation with 50 mg EQ/ kg-1 for 5 wk attenuates enteric oxidative stress and intestinal inflammation by enhancing serum immune and cytokine content (IgG, IL-6, and TGF-ß,) and symbiotic microbiota in heat-stressed broilers. EQ promotes the expression of Hsp70, SOD2, GPx 4, IL-6, and IGF-1 cytokine gene-related anti-inflammatory and growth factors in heat-stressed hepatic broilers. Collectively, EQ-50 could be a suitable feed supplement for attenuating enteric oxidative stress and intestinal inflammation, thereby promoting the productivity of heat-stressed broilers.

Growth performance, carcass traits and meat physical characteristics of growing Japanese quail fed ginger powder and frankincense oil as feed additives.

This work aimed to investigate the effects of dietary frankincense oil and ginger on the growth efficiency of growing Japanese quail, including live body weight, body weight gain, feed intake, feed conversion ratio, carcass traits, and physical characteristics of the meat. In total, 150 unsexed Japanese quail chicks that were 7 d old were utilized in the experiment. The chicks were randomly divided into 5 groups. Each group was divided into 3 replicates with ten birds in a completely randomized design. Group 1 received a basal diet without supplements and was used as a control group. Groups 2 and 3 received basal diets with 250 and 500 mg of ginger per kg of diet, respectively. Groups 4 and 5 received basal diets with 200 and 400 mg of frankincense oil per kg of diet, respectively. Results showed that BW of chicks received 500 mg of ginger and the 2 levels of frankincense oil at 5 wk of age, and 250 mg of ginger and 400 mg of frankincense oil at 6 wk significantly increased. BWG was significantly increased by using 500 mg of ginger and 2 levels of frankincense oil at 1 to 3 wk, 250 mg of ginger and 400 mg of frankincense oil at 3 to 6 wk, and 1 to 6 wk of age, in comparison with the control group. Treatments insignificantly influenced feed intake (FI), and feed conversion ratio (FCR) was improved considerably by using 250 mg of ginger and 400 mg of frankincense at 3 to 6 wk and 1 to 6 wk of age, respectively. Gizzard% was notably reduced with 200 mg of frankincense oil. The pH value of meat was significantly increased by having 2 levels of ginger. Still, water holding capacity and tenderness significantly decreased owing to 500 mg of ginger and 400 mg of frankincense oil. We can conclude that adding ginger and frankincense oil to Japanese quail diets may be beneficial.

Impacts of enzymes and probiotic in improving the utilization of sieved olive pulp meal in growing rabbit diets.

Objective: This research assesses the utilization of sieved olive pulp (SOP) in the diet of growing rabbits through the use of an exogenous enzyme or dry yeast as a pretreatment. Materials and Methods: One hundred sixty-eight male V-Line rabbits aged 5 weeks (weighing 550 ± 25 gm) were randomly divided into seven groups with eight replicates each as follows: the control group was fed a basal diet without supplementation; while the other six groups were fed basal diets containing 20% and 25% of SOP and supplemented with 0.1 gm/kg Econase (E), 0.5 gm/kg dry yeast (Y), and a combination of both. The experiment lasted for 8 weeks. Results: The results indicated that supplementation of E, Y, and EY into rabbit diets containing SOP improved live body weight, body weight gain, feed conversion ratio, and nutrient digestibility. A higher dressing percentage was observed in the groups fed a 20% and 25% SOP diet supplemented with EY (p < 0.05). The treated groups showed an increase in total protein, albumin, globulin, A/G ratio, total antioxidant capacity, superoxide dismutase, and glutathione peroxidase (p < 0.05), while there was a significant decrease in triglycerides, total cholesterol, and malondialdehyde levels (p < 0.05) compared to the control. Rabbit groups fed an SOP diet supplemented with E, Y, or EY demonstrated higher (p < 0.05) economic efficiency compared to the control. Conclusion: Supplementing the diet of rabbits containing SOP with exogenous enzymes and/or dry yeast enhances the nutritional value of SOP while improving rabbit performance, nutrient digestibility, and antioxidant status.

Isolation and characterization of Candida tropicalis B: a promising yeast strain for biodegradation of petroleum oil in marine environments.

The increasing interest in environmental protection laws has compelled companies to regulate the disposal of waste organic materials. Despite efforts to explore alternative energy sources, the world remains heavily dependent on crude petroleum oil and its derivatives. The expansion of the petroleum industry has significant implications for human and environmental well-being. Bioremediation, employing living microorganisms, presents a promising approach to mitigate the harmful effects of organic hydrocarbons derived from petroleum. This study aimed to isolate and purify local yeast strains from oil-contaminated marine water samples capable of aerobically degrading crude petroleum oils and utilizing them as sole carbon and energy sources. One yeast strain (isolate B) identified as Candida tropicalis demonstrated high potential for biodegrading petroleum oil in seawater. Physiological characterization revealed the strain's ability to thrive across a wide pH range (4-11) with optimal growth at pH 4, as well as tolerate salt concentrations ranging from 1 to 12%. The presence of glucose and yeast extract in the growth medium significantly enhanced the strain's biomass formation and biodegradation capacity. Scanning electron microscopy indicated that the yeast cell diameter varied based on the medium composition, further emphasizing the importance of organic nitrogenous sources for initial growth. Furthermore, the yeast strain exhibited remarkable capabilities in degrading various aliphatic and aromatic hydrocarbons, with a notable preference for naphthalene and phenol at 500 and 1000 mg/l, naphthalene removal reached 97.4% and 98.6%, and phenol removal reached 79.48% and 52.79%, respectively. Optimization experiments using multi-factorial sequential designs highlighted the influential role of oil concentration on the bioremediation efficiency of Candida tropicalis strain B. Moreover, immobilized yeast cells on thin wood chips demonstrated enhanced crude oil degradation compared to thick wood chips, likely due to increased surface area for cell attachment. These findings contribute to our understanding of the potential of Candida tropicalis for petroleum oil bioremediation in marine environments, paving the way for sustainable approaches to address oil pollution.

Impacts of willow (Salix babylonica L.) leaf extract on growth, cecal microbial population, and blood biochemical parameters of broilers.

The investigation examined the use of willow leaf extract (WLE) on broiler chickens, examining carcass characteristics, cecal microbiota, antioxidants, and blood parameters. In 4 groups of 300 chicks, a basal diet was given for 5 wk, and the first treatment was basal diet (C). The diets for the remaining 3 treatments (WLE150, WLE300, and WLE450) contained 150, 300, and 450 mg of willow leaf extract /kg, respectively. The study found that birds fed willow leaf extract supplements had significantly greater body weight (BW), body weight gain (BWG), and enhanced feed conversion ratio (FCR) vs. the control group. Birds fed at 450 mg/kg food showed the greatest growth features, carcass weight, liver weight, lower abdominal fat, better low-density lipoprotein (LDL), and high-density lipoprotein (HDL) concentrations, and highest hematological characteristics. Chickens fed diets supplemented with varied doses of willow leaf extract showed significantly increased antioxidant enzyme activity, with higher amounts of glutathione peroxidase (GPx) activity, superoxide dismutase (SOD), total antioxidant capacity (TAC), and lower malondialdehyde (MDA). However, in the study, birds fed a diet supplemented with 450 mg of willow leaf extract per kg meal showed a significant drop of 13.02%, which found no significant variations in hazardous bacteria (Escherichia coli) across 2 treatments (WLE150 and WLE300). In addition, the study discovered that birds fed with varied doses of willow leaf extract had fewer cecum infections (Staphylococci aureus). We conclude that using willow at a level of 450 mg/kg diet can significantly enhance the BWG, FCR, antioxidant levels and beneficial bacteria activity besides the condition of broiler chicken's general health.

Vitamin C and/or garlic can antagonize the toxic effects of cadmium on growth performance, hematological, and immunological parameters of growing Japanese quail.

This study used 300 1-day-old, sexless, developing chicks of Japanese quail to estimate the ability of vitamin C and/or garlic to antagonize the venomous influence of cadmium (Cd) on the hematological, immunological, and performance characteristics of developing Japanese quail. The quail was separated into 5 similar groups of 60 chicks apiece, and 6 duplicates (10 each) were given to each sub-group. The control group received a basal diet without any supplements. The Cd group was nourished with a basal diet of + 80 mg cadmium chloride (CdCl2)/kg diet. The 3rd group was fed a basal diet + 80 mg CdCl2/kg diet and complemented with a 200 mg Vitamin C (Cd + C)/kg diet. The 4th group was nourished with a basal diet + 80 mg CdCl2/kg diet and complemented by a 500 mg dried garlic powder (Cd + G)/kg diet. The 5th group was fed a basal diet + 80 mg CdCl2/kg diet, complemented by a 200 mg vitamin C/kg diet + 500 mg dried garlic powder (Cd + CG)/kg diet. Results showed that in the 5th group in which cadmium was added together with Vit C + garlic, there was an improvement in both live weight gain (1-42 d) and feed consumption (1-21 and 1-42 d ) compared to the group in which Cd was added alone. The addition of Vit C alone and together with garlic seems to completely improve the cadmium-related increase in alkaline phosphatase (ALP), and Aspartate aminotransferase (AST), and Malondialdehyde (MDA) levels when compared to the control. Compared to cadmium-polluted diets, quail that got cadmium and feed additives significantly reduced cadmium residue. In addition, the cadmium group's serum immunoglobulin M (IgM) level decreased significantly. These data imply that dietary supplementation with (C) or (G) may be beneficial in retrogressing the drop in immunoglobulin G (IgG) and IgM caused by Cd and minimizing Cd's deleterious influence on immunity.

Influences of dietary supplementation of ginger powder and frankincense oil on productive performance, blood biochemical parameters, oxidative status and tissues histomorphology of laying Japanese quail.

The objective of the current study was to ascertain the effect of using ginger powder or frankincense oil at different levels on the production rate, biochemical properties of blood, and immune response of laying Japanese quail housed from 12 to 21 wk of age. Three hundred sexually mature quail (200 females and 100 males) were distributed among 5 groups at 12 wk of age in a completely randomized design. Group 1: received basal diet not including additives and acted as a control group. Groups 2 and 3: received a basal diet with 250 and 500 mg ginger/kg feed, respectively. Groups 4 and 5: received a basal diet with 200 and 400 mg frankincense oil/kg feed, respectively. Results revealed that egg production parameters of laying Japanese quail were not influenced by ginger or frankincense oil added in all groups tested during experimental periods except at the time (15-18 wks.). Moreover, egg weight was significantly increased only during the period (15-18 wks.) and total period (12-21 wk of age), and group 5 recorded the highest weight during the 2 periods studied. Feed additives did not impact feed consumption or feed conversion ratio (FCR). Except for WBCs, Hb, and monocytes, treatments impacted blood hematological parameters. Also, blood serum parameters were influenced by feed additives, except total protein, albumin, globulin, and creatinine were not influenced. Moreover, histological examination of the spleen was influenced by feed additives. It is concluded that utilizing frankincense oil or ginger powder in diets of laying Japanese quails enhanced blood serum properties and improved reproductive and productive performance.

Characterization of Immobilized Magnetic Fe3O4 Nanoparticles on Raoultella Ornithinolytica sp. and Its Application for Azo Dye Removal.

A high-performance immobilized bacterial strain coated with magnetic iron oxide nanoparticles was used for Basic Blue 41 azo dye (BB 41 dye) decolorization. To create the coated bacterial strain, Raoultella Ornithinolytica sp. was isolated and identified under the accession number KT213695, then coated with manufactured magnetic iron oxide nanoparticles. SEM and SEM-EDX were used to characterize the coated bacteria and validate its morphological structure formation. The coated Raoultella Ornithinolytica sp. A1 (coated A1) generated a 95.20% decolorization for BB 41 dye at 1600 ppm starting concentration with an optimal dose of coated A1 5 mL/L, pH 8, under static conditions for 24 h at 37 °C. Continuous batch cycles were used, with BB 41 dye (1600 ppm) added every 24 h four times, to achieve a high decolorization efficiency of 80.14%. Furthermore, the metabolites of BB 41 dye biodegradation were investigated by gas chromatographic-mass spectrum analysis (GC-MS) and showed a less toxic effect on the bioindicator Artemia salina. Additionally, 5 mL/L of coated A1 demonstrated the highest decolorization rate (47.2%) when applied to a real wastewater sample after 96 h with a consequent reduction in COD from 592 to 494 ppm.

Zinc oxide nanoparticles induce dose-dependent toxicosis in broiler chickens reared in summer season.

This research evaluates the effect of dietary zinc oxide nanoparticles' (ZnO NPs) supplementation on growth performance, immunity, oxidative antioxidative properties, and histopathological picture of broiler chicken reared in the summer season. A total of 224 1-day-old male Cobb chicks were randomly allocated to seven groups of dietary treatments (n = 32). Seven isocaloric and isonitrogenous diets were formulated. ZnO NPs were added to the basal diet at seven different levels, 0, 5, 10, 20, 40, 60, and 80 ppm/kg diet, respectively, for 35 days. Results indicated that live body weight (g) did not differ significantly (P > 0.05) between treatment groups, whereas compared to control, the 5 ppm ZnO NPs/kg diet recorded the highest live body weight at 21 and 35 days. No significant effects for the feed consumption (g/bird/period) and feed conversion ratio (g feed/g gain) among treated and control birds were observed. Hematological and immunological variables showed significant (P ≤ 0.05) dose-dependent modulations by ZnO NP supplementation. Significant (P ≤ 0.05) differences were observed in the phagocytic activity, phagocytic index, and IgM and IgG between the treatment groups, with the 5 and 10 ppm ZnO NPs/kg diet recording the best values, followed by the 20 ppm ZnO NPs/kg diet. Different supplementations had nonsignificant effects on the digestibility of nutrients (P ≤ 0.05). Histopathological pictures of the kidney, liver, and lymphoid organs, ultrastructural examination of muscle tissues, and expression of inflammatory cytokines showed dose-dependent morphological and structural changes. In conclusion, the ZnO NP supplementation in broiler diet to eliminate the heat stress hazards in summer season is recommended in dose level of not more than 10 ppm/kg diet.

Harvest Season Significantly Influences the Fatty Acid Composition of Bee Pollen.

Seasonal variations in the fatty acid (FA) compositions of pollen loads collected from the Al-Ahsa Oasis in eastern Saudi Arabia throughout one year were determined to identify the optimal season for harvesting bee pollen rich in essential fatty acids (EFAs) and unsaturated fatty acids (UFAs). The highest values (%) of lipids, linolenic acid (C18:3), stearic acid (C18:0), linoleic acid (C18:2), arachidic acid (C20:0), the sum of the C18:0, C18:1, C18:2, and C18:3 concentrations, and EFAs were obtained from bee pollen harvested during autumn. The maximum values (%) of oleic acid (C18:1), palmitic acid (C16:0), UFAs, and the UFA/saturated fatty acid (SFA) ratio were found in bee pollen harvested during summer. The highest concentrations (%) of behenic acid (C22:0), lignoceric acid (C24:0), and SFAs were found in bee pollen harvested during winter. Bee pollen harvested during spring ranked second in its oleic, palmitic, linolenic, stearic, arachidic, behenic, and lignoceric acid concentrations and for EFAs, UFAs, and the UFA/SFA ratio. The lowest SFA concentration was found in bee pollen harvested during summer. Oleic, palmitic, and linolenic acids were the most predominant FAs found in bee pollen. It was concluded that the FA composition of bee pollen varied among the harvest seasons due to the influence of the dominant botanical origins. We recommend harvesting pollen loads during spring and summer to feed honeybee colonies during periods of scarcity and for use as a healthy, nutritious food for humans.

Effect of harvest season on the nutritional value of bee pollen protein.

Bee pollen is a natural product that has valuable nutritional and medicinal characteristics and has recently garnered increasing attention in the food industry due to its nutritive value. Here, we harvested pollen loads from the Al-Ahsa oasis in eastern Saudi Arabia during spring, summer, autumn, and winter in 2018/2019 to compare the nutritional value of bee pollen protein with the amino acid requirements of honeybees and adult humans. Based on the nutritional value of bee pollen protein, the optimal season for harvesting bee pollen was determined. The composition of the bee pollen showed the highest contents of crude protein, total amino acids, leucine, glutamic acid, valine, isoleucine, threonine, and glycine in samples collected in spring. The highest contents of lysine, phenylalanine, threonine, tryptophan, arginine, tyrosine, and cysteine were observed in samples collected in winter. The highest contents of histidine, methionine, and serine were in samples collected in autumn. Moreover, the highest levels of aspartic acid, proline, and alanine were in samples collected in summer. Leucine, valine, lysine, histidine, threonine, and phenylalanine (except in autumn bee pollen) contents in pollen from all four seasons were above the requirements of honeybees. Leucine, valine, histidine, isoleucine (except in autumn bee pollen), lysine (except in spring and summer bee pollen), and threonine (except in winter and spring bee pollen) in all tested samples were above the requirements of adult humans. In comparison with the minimal amino acid requirements of adult humans and honeybees, the 1st limiting amino acid in bee pollen collected during the different seasons was methionine. Bee pollen collected during spring (March-May) and winter (December-February) can be considered a nutritive food source for adult humans and honeybees.

Enhancing the Growth Rate, Biochemical Blood Indices, and Antioxidative Capacity of Broilers by Including Aloe vera Gel in Drinking Water.

Phytogenic herbal extracts received considerable attention in the broilers industry as friendly alternative substitutes to antibiotics. These additives can be included in the food or drinking water to enhance birds' growth rate and well-being. Hence, the current investigation examined the effect of including Aloe vera gel in drinking water on the growth rate, biochemical blood indices, and broilers' antioxidative capacity. Cobb 500 broiler chicks (n = 120), 1 day old of initial weight = 48.6 ± 1.65 g, were divided into three treatments where the control group was fed the basal diet without including Aloe vera gel in drinking water. The second and third groups were fed the basal diet, and Aloe vera gel was included in drinking water at 1 and 1.5%, respectively. The final body weight, weight gain, daily weight gain, and feed conversion ratio were significantly improved in birds that received drinking water with Aloe vera gel at 1.5% compared to the control and 1% groups (P ≤ 0.05). The kidney (creatinine and urea) and liver (ALT and AST) function indices of broilers that received drinking water with or without Aloe vera gel showed no significant differences with the control group (P ≥ 0.05). The blood total protein and albumin had higher values in birds that received drinking water with 1.5% Aloe vera gel than the control (P ≤ 0.05). The total blood cholesterol, triglycerides, and LDL levels were significantly decreased in the group of birds that received 1.5% Aloe vera gel in drinking water (P ≤ 0.05). The HDL level was higher in birds that received drinking water with 1.5% Aloe vera gel than the control (P ≤ 0.05). The total antioxidative capacity (TAC) and glutathione peroxidase (GPX) showed higher activity in the group of birds that received 1.5% Aloe vera gel while the level of malondialdehyde (MDA) was lower in birds that received drinking water with 1.5% Aloe vera gel than the control (P ≤ 0.05). In summary, including Aloe vera gel in drinking water enhanced the growth rate, biochemical blood indices, and broilers' antioxidative capacity.

Statistical optimization of crude oil bio-degradation by a local marine bacterium isolate Pseudomonas sp. sp48.

Pseudomonas sp. sp48, a marine bacterium isolated from Bahary area (Alexandria, Egypt), showed a high potency for oil degradation up to 1.5%. Additionally, it showed an ability to consume aromatic hydrocarbons (phenol & naphthalene) and aliphatic (pentadecane) reaching to 79; 73; 62%, respectively. In the current study, Plackett-Burman factorial design was applied to evaluate culture conditions affecting the degradation potency. Analysis of Plackett-Burman design results revealed that, the most significant variables affecting oil removal were magnesium sulfate, inoculum size, glucose and Triton X-100. To optimize the levels of these significant variables Response Surface Methodology (RSM) was followed. In this respect, the three-level Box-Behnken design was employed and a polynomial model was created to correlate the relationship between the three variables and oil removal. The optimal combinations of the major constituents of media that was evaluated from the non-linear optimization algorithm of EXCEL-Solver was as follows: (w/v%) 1 crude oil, 0.5 peptone, 0.5 yeast-extract, 1 ammonium chloride, 0.7418 D-glucose, 0.5 MgSO4·7H2O, 0.1 Triton X-100 and inoculums size 4.18 ml% in natural sea water at pH 7; 30 °C incubation temperature, 200 rpm for 6 days. The predicted optimum oil removal was 89%, which is 2.4 times more than the basal medium.

Characterization and flocculation properties of a carbohydrate bioflocculant from a newly isolated Bacillus velezensis 40B.

In this study, a bioflocculant with a high flocculation activity (> 98%) produced by strain 40B, which was isolated from a brackish water was investigated By 16S rDNA sequence analysis, strain 40B was identified as Bacillus velezensis. Chemical analysis of the bioflocculant 40B indicated that it contained 2% protein and 98% carbohydrates. FTIR analysis showed the presence of carboxyl, hydroxyl and amino groups, which were preferred for the flocculation process. The optimal concentration for the flocculation activity was 3.5 mg (-1). This polysaccharide could also flocculate kaolin suspension over a wide range of pH (1-10) and temperature (5-85 degrees C) in the presence of CaCl2. The stability of the bioflocculant 40B under various conditions suggests its possible use in the industries and environmental applications. However, no previous report exists on the isolation and characterization of a bioflocculant from the Bacillus velezensis.

Biodegradation of crude petroleum oil and environmental pollutants by Candida tropicalis strain

A local yeast isolate named A was isolated from polluted area of Abou-Qir gulf (Alexandria, Egypt), identified according to a partial sequence of 18sRNA as Candida tropicalis. The isolate showed a high potency in petroleum oil biodegradation as well some hydrocarbons. Morphological changes in cell diameter of this yeast were recognized upon growing the target cell in sea water medium supplemented with petroleum oil as sole carbon source in comparison to the growth in enriched medium. Statistically-based experimental design was applied to evaluate the significance of factors on petroleum oil biodegradation by this yeast isolate. Eleven culture conditions were examined by implementing Plackett-Burman factorial design where aeration, NH4Cl and K2HPO4 had the most positive significance on oil degradation.

Bacillus mojavensis strain 32A, a bioflocculant-producing bacterium isolated from an Egyptian salt production pond.

Bacillus mojavensis strain 32A that exhibited 96.11% flocculation efficiency for clay suspensions was selected from other 15 comparative strains. Under growth condition, strain 32A was able to produce 5.2g/L of purified biopolymer. Its constituent was mainly polysaccharide and protein with proportional of 98.4-1.6% respectively. FTIR spectrum was confirming its chemical analysis. This biopolymer attain very fast sedimentation rate. The cost-effective biopolymer and CaCl(2) dosages were 3mg/L and 5 ml/L respectively that posed 89.7% flocculation efficiency. These dosages were suitable only for clay concentrations ≤5g/L. The maximum flocculation efficiency of the biopolymer recorded at pH 1.0 of clay suspension. The too high (>75°C) or too low (<25°C) clay suspension temperature was unfavorable for the biopolymer flocculation performance. The biopolymer solution utilized high thermal stability over the temperature range of 5-60°C. Furthermore, its pH stability recorded at pH range of 5-9.