Coxiella burnetii (C. burnetii) is one of the most important bacterial agents that cause abortion (Q fever) in ruminants and is a zoonotic disease. The current study reported the first confirmed detection of C. burnetii in sheep in Libya using real-time polymerase chain reaction coupled with high-resolution melt analysis.

Case Description:

Two flocks of sheep suffered abortion, with the aborted fetuses varying in age from early to late term. Vaginal swabs were collected, and DNA was extracted. DNA samples were analyzed using real-time PCR coupled with high-resolution melting (HRM) analysis, and the results showed infection with the zoonotic Q fever caused by C. burnetii. The animals responded to treatment with the antibiotic enrofloxacin, and the abortion was stopped after treatment.

Artemisia herba-alba Asso is a medicinal plant renowned for its therapeutic essential oil. This study characterized the chemical profile and bioactivities of the essential oil from Libyan A. herba-alba. The essential oil, obtained via hydrodistillation with a 2% yield, was analyzed by GC-MS/FID and evaluated for antibacterial (disc diffusion) and anticancer (MTT assay) properties. The oil was dominated by camphor (30.53%) and Thujone (22.47%), classifying it as a camphor-thujone chemotype. It exhibited remarkable antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA; 17.33±1.52 mm), and demonstrated potent, dose-dependent cytotoxicity against MCF-7 breast cancer cells with an IC₅₀ of 0.59 mg/mL. The results validate the traditional use of this plant and highlight its potential as a source of antimicrobial and anticancer agents

Abstract

This study investigated the allelopathic potential of aqueous extracts from two Libyan Artemisia species, Artemisia judaica and Artemisia campestris, on the seed germination and germination rate of Lactuca sativa L. Aerial parts of the plants were collected during the flowering stage in February 2020 from Zintan, Libya. Qualitative phytochemical analysis of the aqueous extracts revealed the presence of tannins, flavonoids, and saponins in both species, while phlobatannins and terpenoids were absent. A bioassay demonstrated that both A. judaica and A. campestris extracts exhibited significant allelopathic activity, inhibiting Lactuca sativa seed germination and decrease the germination rate (GR) in a dose-dependent manner. Complete inhibition of germination (100% IP) was observed at concentrations of 10 mg/ml and 20 mg/ml for both species. The findings suggest that the observed allelopathic effects are likely due to the identified phytochemical constituents, and that these Artemisia species could serve as promising sources for natural herbicides in agricultural weed control.

The genus Thymus is well-known for its aromatic and medicinal properties. Among its species, Thymus algeriensis is widely distributed in the Mediterranean basin, including Libya, where environmental conditions can influence essential oil composition and bioactivity. This study aimed to characterize the chemical profile of T. algeriensis essential oil collected from Gaser Alhaj and evaluate its antibacterial and allelopathic activities. Essential oil was extracted by hydrodistillation and analyzed using GC-MS, revealing six major compounds, with carvacrol as the dominant constituent (77.01%), followed by γ-terpinene, thymol, o-cymene, p-cymene, and caryophyllene. Oxygenated monoterpenes constituted the majority of the oil. The oil exhibited strong antibacterial activity against Escherichia coli and Salmonella gallinarum, and demonstrated dose-dependent allelopathic effects on Lactuca sativa seed germination. Compared to previous studies from Libya, this Gaser Alhaj oil represents a distinct carvacrol-rich chemotype with superior biological activity, highlighting regional chemotypic variation. These findings suggest that T. algeriensis essential oil has promising potential as a natural antimicrobial agent and eco-friendly bioherbicide

AbstractIntroduction

The endemic species Nepeta cyrenaica Quézel & Zaffran, native to northeastern Libya, is valued as an important honey-bearing plant.

Objectives

This study was aimed to examine the micromorphology, phytochemistry, and bioactivity of in vitro-propagated N. cyrenaica for the first time.

Materials and Methods

The leaf indumentum was examined using light and scanning electron microscopy and further characterised for histochemistry. The chemical composition of essential oil (EO) was performed using GC-MS analysis, while dichloromethane (DCM), methanol (ME), ethanol (ET), and aqueous (AQ) extracts were analysed using qualitative and quantitative LC/MS analyses. The antioxidant activities of EO and extracts were assessed using three parallel assays, while enzyme-inhibiting effects were evaluated against four enzymes.

Results

The leaves bear various types of glandular trichomes, with lipophilic secretion predominating. The main EO component of EO was 1,8-cineole. A considerable number of phenolics and iridoids were tentatively identified in the ME extract. Quantitative LC/MS analysis confirmed that ferulic acid, rosmarinic acid, and epigallocatechin gallate were present in the highest amount in the extracts, in which three iridoids were also quantified. Although the ME extract contained the highest amount of polyphenolics and iridoids, the DCM extract showed the best overall biological potential. Additionally, EO exerted the strongest acetylcholinesterase and tyrosinase inhibition.

Conclusion

This study demonstrated that the endemic N. cyrenaica can be efficiently grown under in vitro conditions, where it develops various glandular trichomes that are thought to secrete and/or accumulate bioactive compounds with valuable medicinal potential.

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

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.

ABSTRACT

The essential oil of Thymus algeriensis was analyzed as a potential preservative in soft cheese. We developed a novel method to test the preserving properties of essential oil in soft cheese. Contamination incidence of Penicillium aurantiogriseum was absent after 30 d of storage at 4°C with 25 µL of essential oil added. The antimicrobial activity was tested against 8 bacteria and 8 fungi. Thymus algeriensis oil showed inhibitory activity against tested bacteria at 0.03 to 0.09 mg/mL, and bactericidal activity was achieved at 0.05 to 0.15 mg/mL. For antifungal activity, minimum inhibitory concentrations ranged between 0.01 and 0.04 mg/mL and minimum fungicidal concentrations between 0.01 and 0.04 mg/mL. Furthermore, the oil was also screened for antiradical activity using the 1,1-diphenyl-2-picrylhydrazyl assay. The results showed that the oil was active and achieved half-maximal inhibitory activity at 0.132 mg/mL. We used gas chromatography, gas chromatography-mass spectrometry, and nuclear magnetic resonance spectrometry to investigate the volatile compounds from the oil. Carvacrol was identified as the main compound in the oil, represented by 80.9% of the total constituents, followed by p-cymene (7.7%).

Abstract and figures

We performed a comprehensive study of trichomes considering the medicinal importance of the essential oils produced in glandular trichomes of Salvia aegyptiaca L. and lack of data about leaf trichome characteristics. Micromorphological and histochemical analyses of the trichomes of S. aegyptiaca were carried out using light and scanning electron microscopy. We report that the leaves contained abundant non-glandular unbranched trichomes and two types of glandular trichomes, peltate and capitate, on both leaf surfaces. The abaxial leaf side was covered with numerous peltate and capitate trichomes, while capitate trichomes were more abundant on the adaxial leaf side, where peltate trichomes were rarely observed. The non-glandular trichomes were unicellular papillae and multicellular, uniseriate, two-to-six-celled, erect or slightly leaning toward the epidermis. Peltate trichomes were composed of a basal cell, a short cylindrical stalk cell and a broad head of eight secretory cells arranged in a single circle. Capitate trichomes consisted of a one-celled glandular head, subtended by a stalk of variable length, and classified into two types: Capitate trichomes type I (or short-stalked glandular trichomes) and capitate trichomes type II (or long-stalked glandular trichomes). Histochemical tests showed that the secreted material in all types of S. aegyptiaca glandular trichomes was of a complex nature. Positive reactions to lipids for both types of glandular trichomes were obtained, with especially abundant secretion observed in peltate and capitate trichomes type II.

Abstract

Aims: In the present work, the Libyan wild-growing Thymus capitatus essential oil (EO) was evaluated for its biological properties.

Methods and results: Carvacrol (68.19%) and thymol (12.29%) were found to be the main compounds of the oil. Antioxidant properties, determined by 2,2-diphenylpicrylhydrazyl (DPPH) assay, revealed that IC50 values were 119, 403 and 105 μg ml(-1) for oil, thymol and carvacrol respectively. Microdilution method showed strong antibacterial and especially antifungal potential. Tetrazolium (MTT) colorimetric assay indicated moderate cytotoxicity towards human cell lines MRC-5, HCT 116 and HT-29 (IC50 = 30-150 μg ml(-1)). In adhesion-inhibition assay oil and main compounds reduced adhesion of Escherichia coli and Listeria monocytogenes on colon cells HT-29 (51 and 39% of inhibition against L. monocytogenes and E. coli respectively).

Conclusions: Essential oil of Th. capitatus showed moderate cytotoxic activity, together with excellent antimicrobial effect, in particular against fungi, and significant potential to reduce pathogen colonization in colon.

Abstract: The essential oils obtained by hydrodistillation from the aerial parts of Artemisia judaica L., Artemisia herbaalba Asso. and Artemisia arborescens L. (cultivated) from Libya, were analyzed by GC and GC-MS. The antimicrobial properties were determined using the broth microdilution method against eight bacterial species: Bacillus cereus (clinical isolate), Micrococcus flavus (ATCC10240), Listeria monocytogenes (NCTC7973), Staphylococcus aureus (ATCC6538), Escherichia coli (ATCC35210), Pseudomonas aeruginosa (ATCC27853), Salmonella typhimurium (ATCC13311), Enterobacter cloacae (human isolates) and eight fungal species: Aspergillus niger (ATCC6275), A. ochraceus (ATCC12066), A. versicolor (ATCC11730), A. fumigatus (ATCC1022), Penicillium ochrochloron (ATCC9112), P. funiculosum (ATCC10509), Trichoderma viride (IAM5061) and Candida albicans (human isolate). The major constituents of A. arborescens oil were sesquiterpene hydrocarbons (47.4%). Oxygenated monoterpenes were the dominant constituents in the A. judaica and A. herba-alba oils (54.2% and 77.3%, respectively). Camphor (24.7%) and chamazulene (20.9%) were the major components in the essential oil of A. arborescens, chrysanthenone (20.8%), cis-chrysanthenyl acetate (17.6%) and cis-thujone (13.6%) dominated in the A. herba-alba oil, and the major constituents in the A. judaica oil were piperitone (30.21%) and cis-chrysanthenol (9.1%). The best antimicrobial activity was obtained for A. judaica oil and the lowest effect was noticed in A. arborescens oil. The effect of the tested oils was higher against Gram (+) than Gram (-) bacteria. All three oils showed the best antibacterial activity against Listeria monocytogenes and the lowest against Pseudomonas aeruginosa, Escherichia coli, Enterobacter cloacae, compared to streptomycin and ampicillin. All three oils showed better antifungal activities than ketoconazole, except A. arborescens oil against Aspergillus niger. Keywords: Artemisia judaica; Artemisia herba-alba; Artemisia arborescens; essential oils; antimicrobial activity

Aromatic plant species of genus Thymus are important medicinal plants, highly recommended due to a range of therapeutic properties of their essential oils, commonly known as thyme oil: antirheumatic, antiseptic, antispasmodic, antimicrobial, cardiac, carminative, diuretic and expectorant. The oil is also beneficial in boosting the immune system and helps to fight colds, flu, infectious diseases and chills. It is proved to be a urinary antiseptic, being very helpful for cystitis and urethritis. Scientific validation of traditional uses, and phytochemical and bioactivity evaluation of essential oils from Thymus serpyllum, Thymus algeriensis and Thymus vulgaris were performed.

GC/MS analysis revealed thymol as a major component of T. algeriensis, T. vulgaris and T. serpyllum, with its contribution to the oil 56.0%, 48.9% and 38.5%, respectively. All three essential oils (EOs) exhibited a significant antimicrobial activity against all

Abstract

Desert truffle, Tirmania pinoyi (Maire) Malençon from Libya was chemically characterized in nutritional value, primary and secondary metabolites. Antioxidant (scavenging activity, reducing power and inhibition of lipid peroxidation) and antibacterial activity of its methanolic extract alone and in combination with potassium metabisulfite (E224) were evaluated under in vitro conditions. Furthermore, the effect of the extract on the control of Staphylococcus aureus was examined in a contaminated soup under in situ conditions. T. pinoyi was shown to be rich in carbohydrates (82.60 g/100 g dw) and proteins (8.06 g/100 g dw), being identified four free sugars (rhamnose, fructose, trehalose and mannitol) and three tocopherol isoforms (β-, δ- and γ-tocopherols). Oleic (32.29%), linoleic (29.72%) and palmitic (27.97%) acids were the main fatty acids. p-Hydroxybenzoic (300.65 μg/100 g dw) and cinnamic (8.30 μg/100 g dw) acids were quantified, as also four organic acids: quinic (0.83 g/100 g dw), malic (0.35 g/100 g dw), fumaric (0.05 g/100 g dw) and citric (1.26 g/100 g dw) acids. The methanolic extract of the mushroom showed in vitro antioxidant and antimicrobial activities. Sterilized distillated water containing 0.02% Tween 80 proved to be the most convenient solvent for in situ antimicrobial activity; the extract successfully inhibited the growth of S. aureus in chicken soup in a dose dependent manner.

The composition of essential oil isolated from Salvia fruticosa, wild growing in Libya, was analyzed by GC and GC-MS. Forty-five compounds could be identified. The essential oil contained 1,8-cineole (49.34%), camphor (7.53%), β-pinene (7.38%), myrcene (7.38%), α-pinene (5.15%), β-caryophyllene (4.13%) and α-terpineol (3.25). Antioxidant activity was analyzed using the DPP H free radical scavenging method and low antioxidant activity was found (IC50 = 15.53 mg/ml). The oil was also screened for its antimicrobial activity against eight bacteria (four Gram-negative and four Gram-positive) and eight fungi. The essential oil of S. fruticosa showed minimal inhibitory activity (MIC) at 0.125-1.5 mg/ml and bactericidal (MBC) at 0.5-2.0 mg/ml. In addition, it exhibited fungistatic (MIC) at 0.125-1.0 mg/ml and fungicidal effect (MFC) at 0.125-1.5 mg/ml

The composition of essential oil isolated from Satureja thymbra, growing wild in Libya, was analyzed by GC and GC-MS. The essential oil was characterized by γ-terpinene (39.23%), thymol (25.16%), p-cymene (7.17%) and carvacrol (4.18%) as the major constituents. Antioxidant activity was analyzed using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging method. It possessed strong antioxidant activity (IC50 = 0.0967 mg/mL). The essential oil was also screened for its antimicrobial activity against eight bacterial and eight fungal species, showing excellent antimicrobial activity against the microorganisms used, in particular against the fungi. The oil of S. thymbra showed bacteriostatic activity at 0.001–0.1 mg/mL and was bactericidal at 0.002–0.2 mg/mL; fungistatic effects at 0.001–0.025 mg/mL and fungicidal effects at 0.001–0.1 mg/mL. The main constituents thymol, carvacrol and γ-terpinene also showed strong antimicrobial activity. The commercial fungicide bifonazole showed much lower antifungal activity than the tested oil