Biological Synthesis of Silver Nanoparticles from Lavandula mairei Humbert: Antibacterial and Antioxidant Activities

Hospital-acquired infections involving carbapenem-resistant Acinetobacter baumannii (A. baumannii) and extended spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae pose significant challenges in the intensive care units. The lack of novel antimicrobial drugs amplifies the urgency to explore innovative management strategies. Nanotechnology, with its ability to generate nanoparticles possessing specific properties beneficial in drug delivery and nanomedicine, stands as a pivotal research domain. The objective of this study was to synthesize, for the first time, biologically silver nanoparticles (Ag-NPs) from Lavandula mairei Humbert (L. mairei) plant. The biosynthesized Ag-NPs were characterized by UV-visible spectral analysis, X-Ray diffraction Analysis, Fourier transform infrared spectroscopy analysis, scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy. Subsequently, the antibacterial and antioxidant activities of Ag-NPs were assessed using the micro-dilution method, DPPH test and FRAP assay, respectively. The green-synthesized Ag-NPs exhibited high antibacterial activity against ESBL-producing multidrug-resistant (MDR) strains and against carbapenem-resistant and non-carbapenem-resistant strains of A. baumannii, as well as a very interesting antioxidant activity. The present study suggests that these results hold very promising for the potential application of biologically synthesized Ag-NPs from L. mairei (Ag-LM-NPs) in the invention of novel antibacterial and antioxidant agents.

Anti-adhesion and antibiofilm activities of Lavandula mairei humbert essential oil against Acinetobacter baumannii isolated from hospital intensive care units

This study aimed to assess, for the first time, the anti-adhesion and antibiofilm effects of Lavandula mairei Humbert essential oil against multidrug resistant Acinetobacter baumannii. Scanning electron microscope was used for visualizing its antibiofilm activity and the effect of this oil on surface physicochemical parameters was examined as a possible anti-adhesive target. Chemical analysis of Lavandulaa mairei essential oil showed a high content of carvacrol composition (79.12%). The oil tested exhibited antibacterial efficacy with inhibition diameters of 33 to 37.33 mm and minimum inhibitory and bactericidal concentrations of 1.56 µl ml^-1. The oil inhibited adhesion by 83.66%, detach 73.30% of adherent cells and eliminated 64.02% of the biofilm compared to the untreated control. Lavandula mairei essential oil has proven its possible application as a preventive strategy by intervening in the initial adhesion of Acinetobacter baumannii to polystyrene.

Ethnobotany, traditional knowledge, and nutritional value of Argan (Argania spinosa (L.) Skeels) in Western Anti-Atlas of Morocco

The Souss region in Morocco is known nationally and internationally for its essential knowledge of traditional herbal medicine and the cultural heritage of nutrition. The endemic species Argania spinosa (L.) Skeels is an important crucial plant used by the local population to treat many diseases and prepare some authentic foods. To identify the therapeutic uses of the Argan tree [Argania spinosa (L.) Skeels] and their benefits in preparing authentic foods, the survey was conducted using semi-structured questionnaires. We have achieved 450 interviews with traditional health practitioners and knowledgeable villagers. In the region of Chtouka Aït Baha and Tiznit (Western Anti-Atlas). In parallel with this survey, we collected some old local manuscripts from conventional practitioners in the region. The data obtained were analyzed using specific ethnobotanical indices such as Use Value (UV), Fidelity Level (FL), and Relative Frequency of Citation (RFC). In parallel, we analyzed the nutritional value of some authentic foods derived the argan oil (Amlou, Tagoulla, and Labsis). All 450 interviewees use the argan oil in food or for the preparation of their authentic foods derived (Amlou, Tagoulla, and Labsis); among them, 100 persons use Argan, in addition to food, in the treatment of various diseases with UV and RFC at 1.94 and 0.22, respectively. Among eight treated diseases by argan tree, the treatment of skin and subcutaneous diseases had a very highly significant value of the FL index (98%). Similarly, the analysis of the manuscripts collected in the study area revealed an ancient therapeutic use of the argan tree. The results also show that the Argan oil extracted from the seed is used to prepare authentic foods with significant nutritional value, especially Amlou.

Ethnobotany, phytochemistry and biological properties of Argan tree (Argania spinosa (L.) Skeels) (Sapotaceae) - A review

ETHNOPHARMACOLOGICAL RELEVANCE

The argan [Argania spinosa (L.) Skeels] is one of the most important floristic resource in Morocco, it is the only representative of the Sapotaceae family and Argania genus found in Morocco. This tree is fully exploited by the native populations for nutrition, medication and cosmetics. The argan oil extracted from seed is the main tree product for his large use.

AIM OF THE REVIEW

This review describes the traditional uses, chemical composition and biological activities of different the argan tree parts.

MATERIALS AND METHODS

This review covers the literature available from 1972 to 2021. The informations were collected from electronic databases Scopus, PubMed, Web of Science, SciFinder and Google Scholar.

RESULTS

Argan oil have been used for nutrition, and to treat several diseases, namely rheumatisms, hypercholesterolemia, atherosclerosis, lung infections, newborn gastrointestinal disorders, diabetes, skin and hair hydration. The other parts of Argan tree have been used to treat intestinal disorders, dermatosis, and hair caring, with additional uses such as livestock nutrition, carpentry and heating. The argan oil is primarily composed of unsaturated fatty acids mainly oleic and linoleic acids furthermore the chemical composition, of the others part, are very diversified (flavonoids, terpenoids, triacylglycerols, saponins. …). Diverse biological activities have been reported for argan oil, such as antioxidant, skin water retention, hair protection, cholesterol stabilization, antidiabetic, anticancer and antibacterial. Antimicrobial activities have been reported for argan leaves essential oils, when the fruit pulp organic extract presented very interesting antioxidant activity due to the presence of polyphenols. The argan cake is the seed waste produced during the extraction process, it is traditionally used for skin care and for livestock nutrition. Different biological activities of argan cake have been cited essentially antioxidant, haemoprotective, anti-inflammatory and antimicrobial.

Floristic biodiversity, biogeographical significance, and importance of Morocco's Arganeraie Biosphere Reserve

The coastal and subcoastal areas of west-central Morocco (Safi to Draa River, the Souss Valley, and the southern part of the western High Atlas and northern and southern slopes of the western Anti-Atlas) are characterized by typical Infra-Mediterranean vegetation ranking them amongst the important of the remarkable borderlands of North Africa. The flora is determined by complex historical and environmental factors occurring since the Tertiary period. The originality of this sector is due to the presence of the argan tree (Argania spinosa (L.) Skeels), Moroccan gum (Acacia gummifera Willd), olive trees (Olea europaea L. subsp. maroccana (Greuter & Burdet) P. Vargas & al.), a thermophilic flora adapted to an arid climate with several endemic species. This flora constitutes the final barrier against the desert and is of environmental and socioeconomical interest. Leaves and fruits provide forage material, while wood is used for fuel. Argan fruits are collected for their oily constitutes and for nutritional, cosmetic, and medicinal properties. Additionally, many species of Argan ecosystems are used in medicine and cosmetics. Recognizing its ecological value and local economic importance, the Argan region was declared a UNESCO Biosphere Reserve in 1998. Despite their biogeographical, historical, and socioeconomic value, vegetation structures in west-central Morocco are vulnerable and threatened by human activities. They exhibit high levels of degradation due to increasing clearance, overgrazing, and overexploitation. The area requires high conservation priority and sustainable management strategies for key species and genetic diversity.

Chemical Composition and Biological Screening of the Essential Oils of Micromeria macrosiphon and M. arganietorum (Lamiaceae)

The chemical composition and in vitro biological activities of the essential oil (EO) of Micromeria macrosiphon Coss. and M. arganietorum (J. Emb.) R. Morales, two Lamiaceae endemic to south Morocco, were investigated. GC/MS analysis resulted in the identification of 36 metabolites from the EO of M. macrosiphon, 45 from M. arganietorum. Borneol was the major metabolite in both oils and together with related derivatives such as camphor, accounted for 2/3 of the EO of M. macrosiphon, 1/3 of those of M. arganietorum. Pinene and terpinene derivatives were also present in high proportions. From a chemotaxonomic point of view, the composition of the examined samples may be related to those of other species endemic to Macaronesia. Both EOs showed significant toxicity towards liver HepG2 and melanoma B16 4A5 tumor cell lines at 100 μg/mL; however, they were also cytotoxic towards S17 normal cell lines, with a selectivity index <1. No antibacterial activity was noticed against 52 strains at 100 μg/mL.

A review on Moroccan Thymus species: Traditional uses, essential oils chemical composition and biological effects

ETHNOPHARMACOLOGICAL RELEVANCE

The genus Thymus is among the most important genera in the Lamiaceae family with 215 species and is widely distributed globally, mainly in the Mediterranean region. The genus contains many medicinal plants used in traditional Moroccan medicine for a long time in treating diverse diseases.

AIM OF THE REVIEW

This review describes the traditional uses, biological activities and chemical composition of essential oils (EOs) obtained from Thymus species growing in Morocco.

MATERIALS AND METHODS

Information related to the traditional uses, essential oils chemical composition and biological activities on Moroccan Thymus species were obtained using the electronic databases Web of science, Scopus, SciFinder, Pubmed and Google Scholar.

RESULTS

Moroccan Thymus species have been used in treatment of several diseases, namely diabetes, digestive, circulatory, genital, nervous, urinary, skin and respiratory diseases. Diverse biological activities of Moroccan Thymus species EOs have been reported, such as antibacterial, antifungal, antioxidant, anti-proliferative, anti-tumoral, insecticidal, larvicidal, nematicide, anti-inflammatory, anti-cyanobacterial and anti-acetylcholinesterase. The chemical compositions of Thymus EOs is primarily composed of monoterpenes.

Chemical Composition, Antibacterial Screening and Cytotoxic Activity of Chiliadenus antiatlanticus (Asteraceae) Essential Oil

The chemical composition and in vitro antibacterial and cytotoxic activities of the essential oil (EO) of Chiliadenus antiatlanticus (Emb. & Maire) Gómiz, an asteraceous species endemic to the southwest of Morocco, were investigated. The EO yield was 1.07±0.28 %, twenty-seven metabolites were identified representing more than 96.4 % of the total composition. Camphor (35.7 %) and derivatives, borneol (4.9 %) and camphene (4.2 %) together with intermedeol (19.9 %), α-pinene (15.5 %) and (E)-pinocarveol (4.1 %) were the major constituents. An antibacterial activity was noticed against 24 strains (all Gram-positive) out of 71 at MICs values=100 μg/mL. The EO also showed significant toxicity towards liver HepG2 (55.8 % of cell viability) and melanoma B16 4A5 (41.6 % of cell viability) tumor cell lines at 100 μg/mL.

Ethnopharmacological review of medicinal plants used to manage diabetes in Morocco

Diabetes is a chronic metabolic disorder which affects millions of people every year. If diabetes is not controlled, it can cause serious damage and a number of health complications. The aim of this paper was to review published ethnobotanical and ethnopharmacological evidences of Moroccan plants with antidiabetic potentials. Publications describing the medicinal plants used for the treatment of diabetes in Morocco were searched from the databases, including Google Scholar, Elsevier, Medline, Web of Science, SCOPUS and Pubmed. Other literature source was also used including books and theses available in library. About 750 literature references were studied, and only 240 research publications based on data from different Moroccan provinces published until June 2019 were included in this review. In total, 255 plants species belonging to 70 families were reported. Compositae and Lamiaceae were mentioned as the most represented families. The frequently used plant species in the dwellers of most regions of Morocco are Trigonella foenum-graecum, Artemesia herba-alba, Nigella sativa, Olea europaea, Allium cepa and Marrubium vulgare. This review provides useful information and current scientific knowledge on the medicinal plants used to manage diabetes in Morocco. Medicinal plants reported should be submitted to chemical, pharmacological and clinical studies to identify pharmacologically active metabolites and to confirm their antidiabetic activity.

Medicinal uses, phytochemistry and pharmacology of Ammodaucus leucotrichus

This review summarizes selected scientific evidence on phytochemistry and pharmacological properties of Ammodaucus leucotrichus. Information was gathered via the Internet (using Scopus, PubMed, Google Scholar, Elsevier, Springer, Science Direct, Researchgate and Web of Science) as well as from libraries and local books. Ammodaucus leucotrichus (A. leucotrichus), belongs to the family Apiaceae, has been reported to possess a wide range of traditional medicinal uses including in diarrhea, cough, pulmonary diseases, anorexia, allergy, tachycardia, helminthiasis, stomach pain, gastralgias, otitis, indigestion, cold, fever, anorexia and cardiac diseases. Phytochemical investigations revealed that this plant possesses many bioactive chemical constituents including monoterpenes and their derivatives, sesquiterpenes and their derivatives, tannins, anthracenes compounds, sterols, triterpenes, reducing compounds, alkaloids, phenol acids, saponins, flavonoids and coumarins. The most important pharmacological activities are antioxidant, antibacterial, antifungal, antidiabetic, anti-inflammatory, anticholinesterase and cytotoxicity activities. Ammodaucus leucotrichus has potential for the treatment of a wide range of diseases and has been well studied for its phytochemical properties. However, further scientific studies are needed to explore mechanisms of actions, adverse effects of the extracts, toxicity and the therapeutic effect of major secondary metabolites.

Ethnobotanical survey of medicinal plants used in the traditional treatment of diabetes in Chtouka Ait Baha and Tiznit (Western Anti-Atlas), Morocco

ETHNOPHARMACOLOGICAL RELEVANCE

In Morocco, diabetes mellitus is a major public health problem with more than 1.5 million cases in 2014. Medicinal plants are widely used by the Moroccan population to treat the illness.

AIM OF THE STUDY

The aim of this work is to make an inventory of plant species used in folk medicine for the management of diabetes in Chtouka Ait Baha and Tiznit provinces.

MATERIALS AND METHODS

The survey was carried out by means of semi-structured questionnaires. A total of 380 interviews were conducted with traditional health practitioners and knowledgeable villagers. The data were analyzed through use value (UV), fidelity level (FL) and relative frequency of citation (RFC).

RESULTS

In total, 48 plant species belonging to 25 families were reported. Lamiaceae, Asteraceae and Apiaceae were reported as the most represented families. Six plants are reported for the first time as used in traditional treatment of diabetes and one plant species was previously unknown for its medicinal use to treat diabetes in Morocco. The most frequently cited plant species are Allium sativum L., Salvia officinalis L., Marrubium vulgare L. and Lavandula dentata L. Leaves were the most cited plant part used, decoction is the preferred mode of preparation.

CONCLUSION

This study showed the importance of folk medicine in the healthcare system for the local people living in the study area. The current study represents a useful documentation, which can contribute to preserving knowledge on the use of medicinal plants in this region and to explore the phytochemical and pharmacological potential of medicinal plants.

Use of Cistus aqueous extracts as botanical fungicides in the control of Citrus sour rot

In this work, we investigated the in vitro and in vivo antifungal activity of aqueous extracts obtained from eight Cistus plant species against the development of Geotrichum citri-aurantii, the causal agent of citrus sour rot. The results demonstrate the in vitro effectiveness of all tested Cistus species aqueous extracts against G. citri-aurantii, the inhibition of mycelial growth ranged between 80 and 100%. Furthermore, Cistus aqueous extracts totally inhibited germination of G. citri-aurantii arthrospores at a concentration of 5 mg/mL. Among the plant species tested, C. laurifolius, C. salviifolius, C. monspeliensis, C. ladanifer and C. populifolius displayed the best fungistatic activity since the minimum inhibitory concentration (MIC) was <0.625 mg/mL. Under in vivo conditions, incidence of sour rot was lowered to 8.33% when fruits were treated with aqueous extracts of C. populifolius and C. creticus compared to 100% in the control. Disease severity was lowered to 3.74, 4.47 and 5.13% when fruits were treated with C. creticus, C. ladanifer and C. populifolius aqueous extracts, respectively. Using such these biopesticides in a replacement for synthetic fungicides or in combination with other established disease management practices could help control citrus postharvest decay in a more sustainable and eco-friendly way.

Antifungal properties of organic extracts of eight Cistus L. species against postharvest citrus sour rot

The effectiveness of methanol and chloroform extracts of eight Cistaceae species to control citrus sour rot decay, caused by Geotrichum citri-aurantii, was investigated in both in vitro and in vivo conditions. Methanol extracts of these plant species exhibited more interesting activity against G. citri-aurantii, in both in vitro and in vivo conditions, compared with chloroforme extracts. Under in vitro trials, obtained results showed that methanol extracts of all tested plants revealed a highest significant antifungal activity with inhibition zones that ranged between 12·33 and 16·33 mm in diameter. All tested methanol extracts totally inhibited spore germination when tested at 10 mg ml(-1) . Incidence of sour rot was significantly lowered to 11·11% when fruits were treated with Cistus populifolius and Cistus ladanifer methanol extracts compared with 100% in the control. The disease severity was lowered to 5·19% and 6·04% when fruits were treated with the same methanol extracts respectively.

SIGNIFICANCE AND IMPACT OF THE STUDY

The methanol Cistus extracts had sufficient antifungal activities in vitro and in vivo against G. citri-aurantii to consider its use in the citrus industry after it has been tested under production and natural infection conditions. Such natural products therefore represent a viable alternative approaches for sour rot postharvest management of citrus.

Do island plant populations really have lower genetic variation than mainland populations? Effects of selection and distribution range on genetic diversity estimates

Ecological and evolutionary studies largely assume that island populations display low levels of neutral genetic variation. However, this notion has only been formally tested in a few cases involving plant taxa, and the confounding effect of selection on genetic diversity (GD) estimates based on putatively neutral markers has typically been overlooked. Here, we generated nuclear microsatellite and plastid DNA sequence data in Periploca laevigata, a plant taxon with an island-mainland distribution area, to (i) investigate whether selection affects GD estimates of populations across contrasting habitats; and (ii) test the long-standing idea that island populations have lower GD than their mainland counterparts. Plastid data showed that colonization of the Canary Islands promoted strong lineage divergence within P. laevigata, which was accompanied by selective sweeps at several nuclear microsatellite loci. Inclusion of loci affected by strong divergent selection produced a significant downward bias in the GD estimates of the mainland lineage, but such underestimates were substantial (>14%) only when more than one loci under selection were included in the computations. When loci affected by selection were removed, we did not find evidence that insular Periploca populations have less GD than their mainland counterparts. The analysis of data obtained from a comprehensive literature survey reinforced this result, as overall comparisons of GD estimates between island and mainland populations were not significant across plant taxa (N = 66), with the only exception of island endemics with narrow distributions. This study suggests that identification and removal of markers potentially affected by selection should be routinely implemented in estimates of GD, particularly if different lineages are compared. Furthermore, it provides compelling evidence that the expectation of low GD cannot be generalized to island plant populations.

Use of Moroccan medicinal plant extracts as botanical fungicide against citrus blue mould

The aim of this work was to find an alternative to chemical fungicides currently used in the control of postharvest citrus fruit diseases. In this study, we screened eight Moroccan medicinal and aromatic plants extracted with petroleum ether, chloroform, ethyl acetate and methanol for their anti-fungal activity against Penicillium italicum, the causal agent of citrus blue mould. The anti-fungal activity of these extracts was tested based on the disc diffusion method. Petroleum ether extracts of Inula viscosa, Asteriscus graveolens, Bubonium odorum and Thymus leptobotrys and chloroformic extract of Anvillea radiata revealed the highest significant anti-fungal activity with inhibition zones that ranged between 25·83 and 28·33 mm in diameter. In the minimal inhibitory concentration (MIC) study, we observed that petroleum ether extract of I. viscosa was the most effective extract with both the significantly largest halo (27·50 mm) and the lowest MIC (1 mg ml(-1)). The most active plant extracts in in vitro studies were tested in vivo, and results indicated that solvent extracts of the selected plant species significantly decreased the incidence and severity of blue mould, after 7 and 10 days of storage at 20°C. In addition, Halimium umbellatum methanol extract and T. leptobotrys petroleum ether extract completely inhibited the development of P. italicum under both storage periods, and no phytotoxic effects were recorded on citrus fruit.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study demonstrates that plant extracts have a high potential to control blue mould of citrus and will provide a starting point for discovering new compounds with better activity than chemical fungicides currently available. Such natural products therefore represent a sustainable alternative to the use of chemical fungicides.