This paper presents theoretical proof of the existence of a unique solution to a constrained problem of the Riemann-Liouville fractional differential equation with time delay functions by utilizing the Schauder fixed point theorem. Moreover, we analyzed the continuous dependence of the solution on the initial conditions and other parameters. Further, we investigate the Hyers-Ulam stability of the problem. We introduce some examples and special cases to illustrate our results.

Abstract:

Tobacco is one of the sources that may introduce several heavy metals into the bodies of positive and negative smokers, leading to harmful effects on smokers’ bodies. Because a major number of Libyan populations are smoking different brands of cigarettes alongside raw tobacco leaves which may affect our citizens’ health, accordingly 10 cigarette brands comprising Bon International, Gold Mexico Original, Camel Yellow, D&G, Milano London, Milano, Oris Fliter. Karelia Ligts, Yes and Libyan brand named Ryadi, and another sample of raw tobacco leaves (LRT) planted locally were collected randomly from local shops distributed in Alassaba municipality with aims to determine the total concentration of Cadmium (Cd), Cobalt (Co), Copper (Cu), Lead (Pb) and Zinc (Zn) and calculate the health risk related to the presence of these metals in the most consumed tobacco. The obtained results showed that all collected tobacco samples contained various levels of Cd, Co, Cu Pb and Zn (mg/kg) ranged from 0.38 ± 0.07 to 0.84 ± 0.01, 0.33 ± 0.04 to 0.5 ± 0.07, 15.29 ± 0.88 to 18.75 ± 0.72, 0.42 ± 0.04 to 1.04 ± 0.11 and 14.33 ± 0.33 to 32.45 ± 2.09, respectively. The mean levels of Co, Cu and Zn were within the allowable levels set by the World Health Organization (WHO), whereas Pb and Cd levels were above the acceptable levels. The calculated harm quotient (HQ) of target metals were greater than 1 representing extreme health risk due to the presence of Cd, Cu Pb and Zn in studied tobacco, nevertheless, the HQ of Co were lower than 1 presenting minimal health risk to the smokers. In conclusion, there is a need to emphasize the regulation of the import and tread of tobacco and monitor the content of heavy metals in tobacco to reduce the health effects of these cigarette brands.    

Keywords: Cigarette brands, Heavy metals, Health risk, Smoking, Tobacco.

A B S T R A C T

The current study aimed to the production and partial purification of a cold-active lipase by some fungi isolated from the olive oil processing wastes in Al-Gabal Al-Gharby, Libya. 31 fungal species from 12 genera were isolated. F. solani was the most prevalent comprising 94% of total Fusarium and 28.7% of total fungi, 102 fungal isolates were tested for their lipolytic activity on lipase production agar medium at 10 and 20°C. The most active isolates were Alternaria (2 isolates), Fusarium, and Penicillium (1isolate for each one). Molecular identification of the most active four isolates was carried out by their sequencing (ITS). The four powerful fungal strains' production of cold-active lipase was maximized by optimizing some nutritional and environmental factors. F. solani AUMC 16063 was able to produce the maximum amount of lipase activity (46.66U/mL/min) with specific activity (202.8U/mg), utilizing ammonium sulphate as a nitrogen source after 8 days of incubation at pH 3.0 and 15°C. However, at same condition after 6 days when yeast extract was employed as a nitrogen source, the generated cold-active lipase displayed the highest specific activity of (1550U/mg) and lipase activity (36.74U/ml/min). This is the first study in which the production, partial purification, maximized and characterization of a cold-active lipase enzyme by Fusarium solani.

Keywords: cold active enzymes, Lipase, Fusarium solani, lipolytic activity, specific activity.

The current study aimed to the production and partial purification of a cold-active lipase by som fungi isolated from the olive oil processing wastes in Al-Gabal Al-Gharby, Libya. 31 fungal species from 12 genera were isolated. F. solani was the most prevalent comprising 94% of total Fusarium and 28.7% of total fungi, 102 fungal isolates were tested for their lipolytic activity on lipase production agar medium at 10 and 20°C. The most active isolates were Alternaria (2 isolates), Fusarium, and Penicillium (1isolate for each one). Molecular identification of the most active four isolates was carried out by their sequencing (ITS). The four powerful fungal strains' production of cold-active lipase was maximized by optimizing some nutritional and environmental factors. F. solani AUMC 16063 was able to produce the maximum amount of lipase activity (46.66U/mL/min) with specific activity (202.8U/mg), utilizing ammonium sulphate as a nitrogen source after 8 days of incubation at pH 3.0 and 15°C. However, at same condition after 6 days when yeast extract was employed as a nitrogen source, the generated cold-active lipase displayed the highest specific activity of (1550U/mg) and lipase activity (36.74U/ml/min). This is the first study in which the production, partial purification, maximized and characterization of a cold-active lipase enzyme by Fusarium solani. Keywords: cold active enzymes, Lipase, Fusarium solani, lipolytic activity, specific activity. 

This study was aimed to assess the appropriateness of wastewater to irrigate soft and hard wheat crops. to evaluate growth and productivity of wheat crops. The investigation was conducted during the Agricultural season 2021-2022, at Zawia, Libya. The experiment utilized four different water regimes, including: (S1) Irrigation with 100% fresh water (control), (S2): Irrigated with 50% wastewater and 50% fresh water, (S3): Irrigated with 75% wastewater and 25% fresh water, (S4): irrigated with 100% wastewater. Wheat seeds were sowed in November 2021 in plastic pots and harvested at the start beginning of April 2022. The results showed that using wastewater significantly increased growth parameters, in terms of plant height, wastewater supplemented with (S4) resulted in the highest growth (46.5 cm/plant) in hard wheat and 45.12 cm/plant in soft wheat plants. Higher shoot fresh weights (5.5 g/plant), root fresh weights (3.28 g/plant), and root fresh weights (13.12 and 10.22 g/plant) for hard wheat and soft wheat were achieved, respectively, when wastewater was utilized in isolation as opposed to fresh water. In terms of shoot dry weight, irrigation with (S4) resulted in a yield of 2.00 g/plant and 1.42 g/plant, whereas plants irrigated with fresh water produced 0.92 g/plant and 0.82 g/plant, for soft wheat and soft wheat consecutively. The Sodium Adsorption Ratio (SAR) calculated for the study samples is within the low limits for sodium, which ranges from (0-10), as it was in this study from (1.78 to 4.49), all of which are much smaller than the safe value. and without any damage. This means that all water samples analyzed can be used for irrigation. RSC values ranged from-3 to-110 meq/L, all samples are located at the appropriate limits. SAR, RSC of the samples of water indicate that most of the water has no risk of irrigation. The study determined that the utilization of treated wastewater in the irrigation of agricultural crops, while being monitored, lacks economic viability.

Bread is a staple food for many nations globally. It is prepared by mixing wheat or barley flour with water and other additives. Potassium bromate (KBrO3) is the most used additive in bread industry, because of its efficiency to make the bread cost-effective and favourable to consume. However, KBrO3 is toxic to human and animals due to its ability to affect several body organs, e.g., liver, bones, blood, renal and hepatic, therefore KBrO3 is classified as a carcinogenic chemical and banned for using in the bread industries in most countries. Even though, this material is still in use as bread improver in several countries, nevertheless several oxidising agents was suggested to use as replacements instead of KBrO3 that doesn’t have harmful effects to the consumers. Many technologies have been developed and applied to evaluate the residues of KBrO3 in bakery products. This review paper explored the use of potassium bromate as a flour additive, and its effect on human, animal and environment, and the chemical methods to assess its remains in bread industries.

The demand for drinking water is increasing daily due to the rising world population, alongside the leakage of water, overuse of groundwater, and occurrence of several pollution issues that led to reducing the quality of groundwater. Consequently, in most countries purifying water technologies have been used to obtain drinkable water. Nationally, Libyans use the purified water extensively in their daily needs. Accordingly, to ensure that our citizen utilize harmless water, the quality of the used water and the efficiency of purification units was assessed by analyzing several physical and chemical characteristics of purified water and raw water supplied to the purification units from some local wells and man-made river (MMR) using recommended standard methods. The study results showed that the quality of purified water is excellent, and the purification process reduced the pH, electro conductivity and the concentration of studied chemical properties significantly to values less than the optimum levels (OL) suggested by the World Health Organization (WHO) and Libyan standards (LS) for drinking water. As a conclusion, the studied purified water may use in the daily needs of human with continuously analytical monitoring.