Profiling of Essential Oils from the Leaves of Pistacia lentiscus Collected in the Algerian Region of Tizi-Ouzou: Evidence of Chemical Variations Associated with Climatic Contrasts between Littoral and Mountain Samples

Chemometrics of the composition and antioxidant capacity of essential oils obtained from six Cupressaceae taxa

Essential oils (EOs) are complex and susceptible to environmental conditions, they have a wide range of biological activities and are often used to differentiate between similar species. In this study, gas chromatography-mass spectrometry (GC-MS) coupled with chemometric analysis was applied to systematically analyse and evaluate EOs constituents and antioxidant activity of six Chinese Cupressaceae taxa (Platycladus orientalis Franco, P. orientalis Franco 'Sieboldii', P. orientalis Franco 'Aurea', Juniperus chinensis Roxb., J. chinensis Roxb. 'Kaizuca', and J. sabina L.) under identical conditions. The antioxidant activity of the EOs was evaluated using 2,2 -diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), and ferric reducing power (FRAP), and the total phenolic content (TPC) of the EOs was determined by Folin-Ciocalteau reagent. In total, seventy individual constituents were identified with the main components being α-pinene, sabinene, D-limonene, bornyl acetate, δ-3-carene and β-myrcene. Principal component analysis (PCA) and hierarchal cluster analysis (HCA) successfully discriminated the six taxa into three chemotypes and the unique chemotype revealed that J. chinensis 'Kaizuca' may be a species rather than a cultivar of J. chinensis. The results of OPLS-DA analysis showed that the three compounds screened, namely, α-pinene, sabinene, and δ-3-carene, can completely distinguish Platycladus spp. from Juniperus spp. The DPPH assay results ranged from 576.14 (J. chinensis 'Kaizuca') to 1146.12 (J. sabina) μmol eq Trolox/mL EO, while the ABTS values ranged from 1579.62 (P. orientalis 'Aurea') to 5071.82 (J. sabina) μmol eq Trolox/mL. In the FRAP assay, the values ranged from 1086.50 (J. chinensis 'Kaizuca') to 1191.18 (J. sabina) μmol eq Trolox/ml and the TPC of the EOs studied ranged from 15.17 (J. chinensis 'Kaizuca') to 39.37 (J. sabina) mg GAE/mL EO. The results consistently showed that J. sabina possessed the strongest antioxidant activity and can be preferentially used as a rich source of potentially natural antioxidants.

Comparative studies of four cumin landraces grown in Egypt

One of the significant aromatic plants applied in food and pharma is cumin. Despite its massive trading in Egypt, there are no comprehensive reports on cumin landraces profile screening. This study aimed to investigate the variation in seeds' physical and biochemical profiles and genetic diversity as well as assess the efficiency of seeds' germination under salinity stress. Consequently, during the 2020/2021 growing season, four common cumin seed landraces were gathered from various agro-climatic regions: El Gharbia, El Menia, Assiut, and Qena. Results showed a significant variation in physical profile among the four seeds of landraces. In addition, Assiut had the highest percentage of essential oil at 8.04%, whilst Qena had the largest amount of cumin aldehyde, the primary essential oil component, at 25.19%. Lauric acid was found to be the predominant fatty acid (54.78 to 62.73%). According to ISSR amplification, El Menia presented a negative unique band, whereas other landraces offered a positive band. Additionally, the cumin genotypes were separated into two clusters by the dendrogram, with El Gharbia being located in an entirely separate cluster. There were two sub-clusters within the other cluster: El Menia in one and Assiut and Qena in the other. Moreover, the germination sensitivity to the diverse salinity concentrations (control, 4, 8, 12, and 16 dS/m) findings showed that landraces exhibited varying responses to increased salinity when El Gharbia and El Menia showed a moderate response at four dS/m. Whilst, Qena landraces showed supreme values among other landraces under 12 and 16 dS/m. The majority of the examined features had strong positive associations over a range of salinity levels, according to phenotypic correlation coefficient analysis. To accomplish the aims of sustainable agriculture in Egypt, it would be imperative that the potential breeding program for cumin landraces consider this screening study.

Phytochemical characterization of forest leaves extracts and application to control apple postharvest diseases

The study investigated the antifungal and phytochemical properties of three forest plants (Eucalyptus globulus, Pistacia lentiscus, and Juniperus phoenicea) against apple diseases caused by Colletotrichum gloeosporioides and Alternaria alternata. The determination of the total polyphenol and flavonoid contents in the three aqueous extracts of studied plants showed that E. globulus exhibited the highest contents than those of P. lentiscus and J. phoenicea. Furthermore, the three studied extracts showed very appreciable antioxidant activity with decreasing order: E. globulus, P. lentiscus, and J. phoenicea. The phytochemical analysis showed different common phenolic acids in the three studied plants namely: quinic acid, gallic acid, chlorogenic acid, and caffeoylquinic acid as well as other flavonoids mainly quercetin and catechin. The results of the current study demonstrated that the fungistatic activity of E. globulus EO (4 and 2 µl/ml) seemed to be the most effective under laboratory conditions with an inhibition zone diameter above 16 mm. However, the poisoned food technique indicated that the aqueous extract (80%) and the essential oil (4 µl/ml) of E. globulus exhibited the highest mycelial growth (> 67%) and spore germination (> 99%) inhibition. Preventive treatments with essential oils (4 µl/ml) and aqueous extracts (80%) applied to apple fruits inoculated with A. alternata and C. gloeosporioides resulted in the lowest lesion diameter (< 6.80 mm) and disease severity index (< 15%) and the most favorable inhibitory growth (> 85.45%) and protective potentials (> 84.92%). The results suggest that E. globulus has a brilliant future in the management of anthracnose and Alternaria rot of apple and provide a basis for further studies on its effects under field conditions.

Phytochemical investigation of Pistacia lentiscus L. var. Chia leaves: A byproduct with antimicrobial potential

Pistacia lentiscus L. var. Chia belongs to the Anacardiaceae family, and it is cultivated only in the south part of Chios island, in Greece. Even though it is renowned for its unique resin, Chios mastic gum (CMG), the tree leaves have also been used in traditional medicine, while the annual pruning generates a large biomass of unused by-products. Thus, the aim of the present study was the detailed phytochemical investigation of P. lentiscus var. Chia leaves towards the search of antimicrobial agents. UPLC-HRMS & HRMS/MS based dereplication methods led to the detailed characterization of the aqueous leaf extract. In addition, twelve compounds were isolated and purified from the methanol extract and were identified using spectroscopic and spectrometric methods (NMR, HRMS) belonging to phenolic acids, tannins, flavonoids and terpenes, with the most interesting being 2-hydroxy-1,8-cineole β-D-glucopyranoside which was isolated for the first time in the Anacardiaceae family. Remarkably, based on NMR data, methanol and aqueous extracts were found to be particularly rich in shikimic acid, a valuable building block for the pharmaceutical industry, for instance in the synthesis of the active ingredient of Tamiflu®, oseltamivir. Finally, extracts (EtOAc, MeOH, H2O) and major compounds i.e., shikimic acid, 2-hydroxy-1,8-cineole β-D-glucopyranoside and myricitrin were evaluated for their antimicrobial properties. MeOH and H2O mastic leaf extracts as well as myricitrin and, particularly, 2-hydroxy-1,8-cineole β-D-glucopyranoside showed significant selective activity against pathogenic Mucorales, but not against Aspergilli (Aspergillus nidulans, Aspergillus fumigatus), Candida albicans or bacteria (Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis).

Pistacia lentiscus essential oil and its pure active components as acaricides to control Dermanyssus gallinae (Acari: Mesostigmata)

The goal of this work was to assess the in vitro acaricidal effects of Pistacia lentiscus essential oil and its pure active components against red poultry mites Dermanyssus gallinae as an alternative to chemical acaricide (formamidines). Essential oil was obtained using hydrodistillation and then analyzed using GC-MS. The following major components were identified: α-pinene (20.58 %), D-Limonene (18.16 %), β-Myrcène (15.06 %), 4-Terpineol (7.68 %), caryophyllene (5.45 %) and γ-terpinene (5.21 %). The toxicity of essential oil and its six monoterpenes were tested at concentrations ranging from 0.43 to 3.50 mg/cm2, using contact and spraying bioassays. Toxicity was expressed as a lethal concentration (LC50 or LC90). The experiment results revealed that activity was method and concentration dependent, and the spraying method was more effective than the contact bioassay for acaricidal activity. In this bioassay, the highest mortality was observed with 4-Terpineol. The LC50 was estimated to be 0.184 mg/cm2 for this substance, followed by α-pinene, the LC50 of which was estimated to be 0.203 mg/cm2. Caryophyllene and γ-terpinene were found less effective in controlling D. gallinae. P. lentiscus oil and its major compounds were also evaluated for anti-acetylcholinesterase (AChE) effects; 4-Terpineol was found to be the most effective AChE inhibitor with IC50 values reaching 18.73 ± 2.83 µg/mL. This framework pointed out the importance of the traditional use of P. lentiscus as an ecofriendly alternative against ectoparasite of veterinary importance; D. gallinae. In vivo trials should also be conducted to assure the safe use of essential oils or individual compounds and to achieve efficient acaricidal property.

Unveiling the Chemical Profiling Antioxidant and Anti-Inflammatory Activities of Algerian Myrtus communis L. Essential Oils, and Exploring Molecular Docking to Predict the Inhibitory Compounds against Cyclooxygenase-2

Considering the large spectrum of side effects caused by synthetic drugs and the development of natural alternatives utilizing Algerian flora, this study aimed to place a spotlight on the chemical profile and antioxidant and anti-inflammatory activities of Myrtus communis L. essential oils (MCEOs). In this study, essential oils (EOs) were collected via hydro-distillation of the plant's leaves, and a chemical constituent analysis was performed using gas chromatography-mass spectrophotometry (GC-MS). The in vitro antioxidant activity was evaluated using DPPH, ABTS, and hydroxyl radical scavenging tests. The in vitro anti-inflammatory capacity was estimated by studying the antidenaturation effect using bovine serum albumin (BSA) as a protein model. The in vivo anti-inflammatory activity was carried out by utilizing the classical model of carrageenan-induced paw edema in rats, using diclofenac (DCF) as the reference drug. Moreover, the molecular interaction of the compounds obtained from the GC-MS analysis was studied within the binding site of cyclooxygenase-2 (COX-2) using an in silico approach as the confirmatory tool of the in vitro and in vivo experiments. The GC-MS analysis revealed that MCEOs were mainly composed of oxygenated monoterpenes (70.56%), oxygenated sesquiterpenes (3.1%), sesquiterpenes (4.17%), and monoterpenes (8.75%). Furthermore, 1,8-cineole was the major compound (19.05%), followed by cis-geranyl acetate (11.74%), methyl eugenol (5.58%), α-terpineol (4.62%), and β-myrcene (4.40%). MCEOs exhibited remarkable concentration-dependent free radical scavenging activity, with an IC50 of 15.317 ± 0.340 µg/mL, 18.890 ± 2.190 µg/mL, and 31.877 ± 0.742 µg/mL for DPPH, ABTS, and hydroxyl radical, respectively. The significant in vitro anti-inflammatory activity due to the inhibition of BSA denaturation was proportional to the EO concentration, where the highest value was recorded at 100 μg/mL with an approximately 63.35% percentage inhibition and an IC50 of 60.351 ± 5.832 μg/mL. MCEOs showed a good in vivo anti-inflammatory effect by limiting the development of carrageenan-induced paw thickness. The in silico study indicated that, among the 60 compounds identified by the GC-MS analysis, 9 compounds were observed to have a high binding energy to cyclooxygenase-2 as compared to diclofenac. Our study revealed that EOs from Algerian Myrtus communis L. can be considered to be a promising candidate for alleviating many debilitating health problems and may provide new insights in the fields of drug design, agriculture, and the food industry.

Chios Mastic Gum: Chemical Profile and Pharmacological Properties in Inflammatory Bowel Disease: From the Past to the Future

Chios mastic gum, the product of the tree Pistacia lentiscus var. Chia, has been used for more than 2500 years in traditional Greek medicine for treating several diseases, thanks to the anti-inflammatory and antioxidant properties of its components. Despite the long-time use of mastic in gastroenterology and in particular in chronic-inflammation-associated diseases, to date, the literature lacks reviews regarding this topic. The aim of the present work is to summarize available data on the effects of P. lentiscus on inflammatory bowel disease. A comprehensive review of this topic could drive researchers to conduct future studies aimed at deeply investigating P. lentiscus effects and hypothesizing a mechanism of action. The present review, indeed, schematizes the possible bioactive components of mastic gum. Particular care is given to P. lentiscus var. Chia medicaments' and supplements' chemical compositions and their pharmacological action in inflammatory bowel disease.

Chemical Profiling and Biological Properties of Essential Oils of Lavandula stoechas L. Collected from Three Moroccan Sites: In Vitro and In Silico Investigations

The aim of this study was the determination of the chemical compounds of Lavandula stoechas essential oil from Aknol (LSEO_A), Khenifra (LSEO_K), and Beni Mellal (LSEO_B), and the in vitro investigation of their antibacterial, anticandidal, and antioxidant effects, and in silico anti-SARS-CoV-2 activity. The chemical profile of LSEO was determined using GC-MS-MS analysis, the results of which showed a qualitative and quantitative variation in the chemical composition of volatile compounds including L-fenchone, cubebol, camphor, bornyl acetate, and τ-muurolol; indicating that the biosynthesis of essential oils of Lavandula stoechas (LSEO) varied depending on the site of growth. The antioxidant activity was evaluated using the ABTS and FRAP methods, our results showed that this tested oil is endowed with an ABTS inhibitory effect and an important reducing power which varies between 4.82 ± 1.52 and 15.73 ± 3.26 mg EAA/g extract. The results of antibacterial activity of LSEO_A, LSEO_K and LSEO_B, tested against Gram-positive and Gram-negative bacteria, revealed that B. subtilis (20.66 ± 1.15-25 ± 4.35 mm), P. mirabilis (18.66 ± 1.15-18.66 ± 1.15 mm), and P. aeruginosa (13.33 ± 1.15-19 ± 1.00 mm) are the most susceptible strains to LSEO_A, LSEO_K and LSEO_B of which LSEO_B exhibits bactericidal effect against P. mirabilis. furthermore The LSEO exhibited varying degrees of anticandidal activity with an inhibition zones of 25.33 ± 0.5, 22.66 ± 2.51, and 19 ± 1 mm for LSEO_K, LSEO_B, and LSEO_A, respectively. Additionally, the in silico molecular docking process, performed using Chimera Vina and Surflex-Dock programs, indicated that LSEO could inhibit SARS-CoV-2. These important biological properties of LSEO qualify this plant as an interesting source of natural bioactive compounds with medicinal actions.

Metabolomics-Based Profiling via a Chemometric Approach to Investigate the Antidiabetic Property of Different Parts and Origins of Pistacia lentiscus L

Pistacia lentiscus L. is a medicinal plant that grows spontaneously throughout the Mediterranean basin and is traditionally used to treat diseases, including diabetes. The aim of this work consists of the evaluation of the α-glucosidase inhibitory effect (i.e., antidiabetic activity in vitro) of different extracts from the leaves, stem barks and fruits of P. lentiscus harvested on mountains and the littoral of Tizi-Ouzou in Algeria. Metabolomic profiling combined with a chemometric approach highlighted the variation of the antidiabetic properties of P. lentiscus according to the plant's part and origin. A multiblock OPLS analysis showed that the metabolites most involved in α-glucosidase inhibition activity were mainly found in the stem bark extracts. The highest inhibitory activity was found for the stem bark extracts, with averaged inhibition percentage values of 84.7% and 69.9% for the harvested samples from the littoral and mountain, respectively. On the other hand, the fruit extracts showed a lower effect (13.6%) at both locations. The UHPLC-ESI-HRMS characterization of the metabolites most likely responsible for the α-glucosidase-inhibitory activity allowed the identification of six compounds: epigallocatechin(4a>8)epigallocatechin (two isomers), (epi)gallocatechin-3'-O-galloyl-(epi)gallocatechin (two isomers), 3,5-O-digalloylquinic acid and dihydroxy benzoic acid pentoside.