Abstract:

Nepeta cyrenaica Quézel & Zaffran (Lamiaceae), an endemic species of Libyan flora, is here characterized for the first time for its phytochemical composition and biological activities. Phenolic composition, antioxidant and enzyme inhibiting effects of extracts, prepared from five-week-old in vitro propagated N. cyrenaica shoots, were evaluated. Extraction was performed using dichloromethane, methanol, 96% ethanol or hot distilled water. LC-MS analysis showed that the methanol extract contained the highest amount of phenolic components, especially ferulic and rosmarinic acids (1300.73 mg/kg and 528.88 mg/kg, respectively), and epigallocatechin gallate (719.05 mg/kg). The strongest antioxidant activity was recorded for aqueous extract in DPPH assay (66.91%) and dichloromethane extract in β-carotene bleaching assay (81.06%), both tested at the concentration of 2 mg/mL. Concerning α-glucosidase inhibition, dichloromethane extract was shown to possess a higher inhibition capacity than acarbose at the concentration of 2 mg/mL (95.33% vs. 88.29%). The aqueous extract exhibited higher acetylcholinesterase inhibition than the other tested extracts, which was lower compared to the positive control, galantamine. Although methanol extract contained the highest amount of polyphenolics, dichloromethane and aqueous extracts were shown to be more suitable for the extraction of bioactive components. In conclusion, endemic N. cyrenaica could be efficiently propagated through in vitro propagation protocols as a polyphenolic-rich plant with valuable medicinal potential.

Keywords: biological activities; extracts; in vitro propagation; Nepeta cyrenaica

This study considers the diagenetic processes and the depositional settings of Lower Jurassic gypsum of the Bi'r Elghanem Formation in the northwestern of Libya. The paleo-environment study has revealed a variety of depositional environment ranging from lagoonal to fluvial deposit and evaporitic basins, which become intensely saline as a result of evaporation due to (semi-) arid environments. Samples were analyzed using elemental analysis, statistical evaluation such as Multiple Correlations, Principal Component Analysis, and mineralogical evidence to determine their mode of environmental deposition, mineralogical and geochemical composition. The geochemical results indicate that gypsum has evidence of mineral substitutions and displacement, suggesting a homologous mechanism for lithofacies and subsequent textural change. The development of gypsum minerals in a variety of lithologies and textures is aided by eustatic fluctuations in lake water level due to regional tectonism and climate.

Abstract

Abstract

Introduction:

Coronavirus Disease 2019 (COVID-19) is an infectious res-

piratory disease caused by SARS-CoV-2. The disease was first broke out in

Wuhan City, Hubei Province, China and subsequently spread to all countries

and was considered by WHO as a worldwide pandemic. This study is aimed

to determine the epidemiology of SARS-CoV-2 and the presence of UK va-

riants in Zintan city of Libya taking some risk factors into account. Me-

thods: In a cross-sectional retrospective study, a total of 15486 nasopha-

ryngeal swabs were collected from COVID-19 suspected patients, travelers

and people need disease-free certificates for hospital admission, etc. The

samples were collected during the period from August 2020 to June 2021

and tested using real-time RT -PCR (rRT-PCR) kits for SARS-CoV-2 and

UK variants. Age groups, sex, and monthly weather were considered as risk

factors. Results: The positivity rate of COVID-19 in Zintan city was esti-

mated to be (3891; 25.12%) for the period from August 2020 to June 2021.

Females showed significantly (p < 0.05) higher positivity rate (2100; 54%) as

compared to males (1791; 46%). Out of the 3891 positive cases, 52 were de-

ceased. The Case Fatality Rate (CFR) was 1.33 recorded significantly in cas-

es aged ≥ 65 years which was higher in males (56.66%) than females (43.33%).

The peak of the first wave of infection was recorded in October 2020 (590;

15.15%) whereas the peak of the second wave of infection was recorded in

April 2021 (727; 18.71%). The positivity rate was decreased as the tempera-

ture increased. UK variant is detected firstly in May 2021 with the percen-

tage of 6.2% of tested samples. Conclusions: Health Authorities are en-

crease phase of infection to stop transmission of the virus in the next wave.

Early detection of new variants and studying their genetic characteristics

play a valuable role in prevention and control.

Keywords

SARS

-

CoV

-

2, UK Variant, Epidemiology, Zintan,

Libya, rRT

-

PCR.

Lithostratigraphically, the Sidi As sid Formation (Upper Cretaceous) in the El Zintan section (JabalNafusah, NW Libya) consists of three units: upper marl, middle marl with intercalations of dolostone, and lower dolostone. Based on crystal size and shape, three types of dolomite have been classified. Fine crystalline dolomite (D1) consists of nonplanar dolomites, fine to medium crystalline dolomite (D2), and very coarse, consisting of mostly planar dolomites (D-3). The Cathodoluminescence technique also showed that most of these dolomites have bright yellow to red and dull orange luminescence and zoning. Based on X-ray diffraction (XRD), all dolomites are relatively well ordered and non to nearly stoichiometric dolomite. The stable isotopic studies and element analysis show that the major elements such as sodium (D1: 412.166 ppm; D2: 175 ppm; D3: 420 ppm), strontium (D1: 107 ppm; D2: 85 ppm; D3: 81.2 ppm), manganese (D1: 271 ppm; D2: 91 ppm; V3: 242 ppm), and iron (D1: 4856.66 ppm; D2: 373 ppm; D3: 3287 ppm) and the values of the stable isotope of oxygen (D1:-2.202‰; D2:-2.131; D3:-4.359‰) and carbon (D1: 2.080; D2: 2.076‰; D3: 1.581‰). The values of major elements and depletion of the carbon and oxygen isotopes can be related to the effects of temperature diagenetic, and mesosaline reflux of dolomitizing fluids during the early diagenesis. These dolomites originated in a tidal environment in this Formation. The major sources of magnesium for the dolomites are seawater and hypersaline fluids.

In this study, we present the new generalized derivative and integral operators which are based on the newly constructed new generalized Caputo fractal–fractional derivatives (NGCFFDs). Based on these operators, a numerical method is developed to solve the fractal–fractional differential equations (FFDEs). We approximate the solution of the FFDEs as basis vectors of shifted Legendre polynomials (SLPs). We also extend the derivative operational matrix of SLPs to the generalized derivative operational matrix in the sense of NGCFFDs. The efficiency of the developed numerical method is tested by taking various test examples. We also compare the results of our proposed method with the methods existed in the literature In this paper, we specified the fractal–fractional differential operator of new generalized Caputo in three categories: (i) different values in  and fractal parameters, (ii) different values in fractional parameter while fractal and  parameters are fixed, and (iii) different values in fractal parameter controlling fractional and  parameters.

The groundwater aquifers in Azintan, northwestern Libya suffer from an acute shortage of water. The groundwater was evaluated to determine its suitability for drinking and irrigation purposes from major two aquifers in north and south of Azintan area. This study carried out to assess the groundwater quality and to identify major affecting variables. Twelve samples from the two aquifers were collected. The two aquifers were collected and analyzed for total dissolved solid (TDS), electrical conductivity (EC), pH, Ca2+, Mg2+, Na+, K+, Cl-, SO42-, CO32- and HCO3-. The results show that, the groundwater in many places is dominated by higher concentrations of Cl-, SO42- and HCO3-. Two water types were recognized in this region are Cl-SO4-Na-Ca and Cl-SO4-Na. Gibbs and Piper method, as well as the hardness, soluble sodium percentage and the permeability index all have been used to assess the diagram quality of the groundwater of aquifers. Further, the multiple correlations and Cluster Analysis of groundwater quality parameters were carried out for further classification and interpretation of the groundwater quality. Finally, water qualities in the study area are compared with Libyan standards and WHO guidelines of drinking water and irrigation purposes.

Abstract

The growth of two wetland forage grasses Leptochloa fusca (L.) Kunth. and Echinochloa stagnina (L.) P. Beauv. was investigated under NaCl salinity regarding the morphological traits, plant chemical composition, photosynthesis and the antioxidant enzymes POD and CAT. Plants of both species were irrigated with 0, 50, 100, 200, 300 and 400 mM NaCl in a sand/perlite mixture of 1:1 (v/v). Salinity negatively affected morphological traits and plant biomass of both species, particularly E. stagnina. Soluble sugars and proline within limits, protein contents of the foliage were increased to different extents by increasing salinity, but insoluble sugar decreased. K⁺/Na⁺ ratio of shoot and root of both species was decreased as a consequence of Na⁺ accumulation and restricted K⁺ uptake. NaCl salinity adversely affected photosynthetic rate, transpiration rate, stomatal conductance and water use efficiency of both species particularly E. stagnina. Tolerance of L. fusca and E. stagnina to salinity stress can be based on stomatal closure and reduction in leaf area, in order to minimize water loss via transpiration and increase the activity of some antioxidant enzymes to detoxifying ROS generated during stress.

Vulvovaginal candidiasis causes sufferers much discomfort. Phytotherapy with garlic has been reported to be a possible alternative form of treatment; however, it is unknown why patients report varying success with this strategy. Fresh garlic extract has been shown to down-regulate the putative virulence gene, SIR2 in C. albicans. Our study aimed to see if previous observations were reproducible for the gene responsible for Candidalysin (ECE1). Two clinical strains from patients with reported variable efficacy of using garlic for the treatment of vulvovaginal candidiasis were compared through biofilm assays and antimicrobial susceptibility. Real-time PCR was used to assess changes in gene expression when exposed to garlic. Treatment with fresh garlic extract and pure allicin (an active compound produced in cut garlic) resulted in a decrease in SIR2 expression in all strains. In contrast, ECE1 expression was up-regulated in a reference strain and an isolate from a patient unresponsive to garlic therapy, while in an isolate from a patient responsive to garlic therapy, down-regulation of ECE1 occurred. future studies that investigate the effectiveness of phytotherapies should take into account possible varying responses of individual strains and that gene expression may be amplified in the presence of serum.