Dietary aflatoxins exposure, environmental enteropathy, and their relation with childhood stunting.

Childhood stunting is a global phenomenon affecting more than 149 million children under the age of 5 worldwide. Exposure to aflatoxins (AFs) in utero, during breastfeeding, and consumption of contaminated food affect the gut microbiome, resulting in intestinal dysfunction and potentially contributing to stunting. This review explores the potential relationship between AF exposure, environmental enteropathy and childhood stunting. AFs bind to DNA, disrupt protein synthesis and elicit environmental enteropathy (EE). An EE alters the structure of intestinal epithelial cells, impairs nutrient uptake and leads to malabsorption. This article proposes possible intervention strategies for researchers and policymakers to reduce AF exposure, EE and childhood stunting, such as exposure reduction, the implementation of good agricultural practices, dietary diversification and improving environmental water sanitation and hygiene.

Critical review on phytoremediation of polyfluoroalkyl substances from environmental matrices: Need for global concern.

Poly- and perfluoroalkyl substances (PFAS) are a class of emerging organic contaminants that are impervious to standard physicochemical treatments. The widespread use of PFAS poses serious environmental issues. PFAS pollution of soils and water has become a significant issue due to the harmful effects of these chemicals both on the environment and public health. Owing to their complex chemical structures and interaction with soil and water, PFAS are difficult to remove from the environment. Traditional soil remediation procedures have not been successful in reducing or removing them from the environment. Therefore, this review focuses on new phytoremediation techniques for PFAS contamination of soils and water. The bioaccumulation and dispersion of PFAS inside plant compartments has shown great potential for phytoremediation, which is a promising and unique technology that is realistic, cost-effective, and may be employed as a wide scale in situ remediation strategy.

Reviewing the role of biochar in paddy soils: An agricultural and environmental perspective.

The main challenge of the twenty-first century is to find a balance between environmental sustainability and crop productivity in a world with a rapidly growing population. Soil health is the backbone of a resilient environment and stable food production systems. In recent years, the use of biochar to bind nutrients, sorption of pollutants, and increase crop productivity has gained popularity. This article reviews key recent studies on the environmental impacts of biochar and the benefits of its unique physicochemical features in paddy soils. This review provides critical information on the role of biochar properties on environmental pollutants, carbon and nitrogen cycling, plant growth regulation, and microbial activities. Biochar improves the soil properties of paddy soils through increasing microbial activities and nutrient availability, accelerating carbon and nitrogen cycle, and reducing the availability of heavy metals and micropollutants. For example, a study showed that the application of a maximum of 40 t ha-1 of biochar from rice husks prior to cultivation (at high temperature and slow pyrolysis) increases nutrient utilization and rice grain yield by 40%. Biochar can be used to minimize the use of chemical fertilizers to ensure sustainable food production.

Micro (nano) plastics uptake, toxicity and detoxification in plants: Challenges and prospects.

Plastic pollution has emerged as a global challenge affecting ecosystem health and biodiversity conservation. Terrestrial environments exhibit significantly higher plastic concentrations compared to aquatic systems. Micro/nano plastics (MNPs) have the potential to disrupt soil biology, alter soil properties, and influence soil-borne pathogens and roundworms. However, limited research has explored the presence and impact of MNPs on aquaculture systems. MNPs have been found to inhibit plant and seedling growth and affect gene expression, leading to cytogenotoxicity through increased oxygen radical production. The article discusses the potential phytotoxicity process caused by large-scale microplastics, particularly those unable to penetrate cell pores. It also examines the available data, albeit limited, to assess the potential risks to human health through plant uptake.

A review of the effects of environmental hazards on humans, their remediation for sustainable development, and risk assessment.

In the race for economic development and prosperity, our earth is becoming more polluted with each passing day. Technological advances in agriculture and rapid industrialization have drastically polluted the two pillars of natural resources, land and water. Toxic chemicals and microbial contaminants/agents created by natural and anthropogenic activities are rapidly becoming environmental hazards (EH) with increased potential to affect the natural environment and human health. This review has attempted to describe the various agents (chemical, biological, and physical) responsible for environmental contamination, remediation methods, and risk assessment techniques (RA). The main focus is on finding ways to mitigate the harmful effects of EHs through the simultaneous application of remediation methods and RA for sustainable development. It is recommended to apply the combination of different remediation methods using RA techniques to promote recycling and reuse of different resources for sustainable development. The report advocates for the development of site-specific, farmer-driven, sequential, and plant-based remediation strategies along with policy support for effective decontamination. This review also focuses on the fact that the lack of knowledge about environmental health is directly related to public health risks and, therefore, focuses on promoting awareness of effective ways to reduce anthropological burden and pollution and on providing valuable data that can be used in environmental monitoring assessments and lead to sustainable development.

Phytochemical Variability of Essential Oils of Two Balkan Endemic Species: Satureja pilosa Velen. and S. kitaibelii Wierzb. ex Heuff. (Lamiaceae).

Satureja pilosa and S. kitaibelii (Lamiaceae) are Balkan endemic plant species, and the composition of their essential oil (EO) is highly variable. The aim of the present study was to establish: (1) the EO variability in two populations of S. pilosa (the intrapopulation), and (2) the EO variation in S. kitaibelii between nine populations (interpopulation) from Bulgaria and two from Serbia. The EOs of two Satureja species were obtained from aboveground plant parts by hydrodistillation and were analyzed by GC/MS/FID. Overall, the EO yield on the intrapopulation level of S. pilosa varied from 0.54% to 2.15%, while the EO of S. kitaibelii varied from 0.04% to 0.43% (interpopulation). The EO of S. pilosa was found to contain thymol and carvacrol as the main constituents, with other major constituents being p-cymene and γ-terpinene. S. pilosa samples in both studied populations formed six chemical groups. The major constituents (p-cymene, terpinen-4-ol, bornyl acetate, γ-muurolene, endo-borneol, cis-ß-ocimene, trans-ß-ocimene, carvacrol, α-pinene, thymoquinone, geranial, geranyl acetate, spathulenol, and caryophyllene oxide) of S. kitaibelii EO were considered for grouping the populations into ten chemotypes. The present study is the first report on the interpopulation diversity of S. kitaibelii EOs in Bulgaria. It demonstrated variability of the EOs between and within the populations of S. kitaibelii from Bulgaria. This study identified promising genetic material that could be further propagated and developed into cultivars for commercial production of S. kitaibelii and S. pilosa, thereby reducing the impact of collection on wild populations.

Applications of Essential Oils and Plant Extracts in Different Industries.

Essential oils (EOs) and plant extracts are sources of beneficial chemical compounds that have potential applications in medicine, food, cosmetics, and the agriculture industry. Plant medicines were the only option for preventing and treating mankind's diseases for centuries. Therefore, plant products are fundamental sources for producing natural drugs. The extraction of the EOs is the first important step in preparing these compounds. Modern extraction methods are effective in the efficient development of these compounds. Moreover, the compounds extracted from plants have natural antimicrobial activity against many spoilage and disease-causing bacteria. Also, the use of plant compounds in cosmetics and hygiene products, in addition to their high marketability, has been helpful for many beauty problems. On the other hand, the agricultural industry has recently shifted more from conventional production systems to authenticated organic production systems, as consumers prefer products without any pesticide and herbicide residues, and certified organic products command higher prices. EOs and plant extracts can be utilized as ingredients in plant antipathogens, biopesticides, and bioherbicides for the agricultural sector. Considering the need and the importance of using EOs and plant extracts in pharmaceutical and other industries, this review paper outlines the different aspects of the applications of these compounds in various sectors.

Insights on the bioremediation technologies for pesticide-contaminated soils.

The fast pace of increasing human population has led to enhanced crop production, due to which a significant increase in the application of pesticides has been recorded worldwide. Following the enhancement in the utilization of pesticides, the degree of environmental pollution, particularly soil pollution, has increased. To address this challenge, different methods of controlling and eliminating such contaminants have been proposed. Various methods have been reported to eradicate or reduce the degree of contamination of pesticides in the soil. Several factors are crucial for soil contamination, including pH, temperature, the number, and type/nature of soil microorganisms. Among the accessible techniques, some of them respond better to contamination removal. One of these methods is bioremediation, and it is one of the ideal solutions for pollution reduction. In this innovative technique, microorganisms are utilized to decompose environmental pollutants or to curb pollution. This paper gives detailed insight into various strategies used for the reduction and removal of soil pollution.

Biological Activity of Essential Oils of Four Juniper Species and Their Potential as Biopesticides.

The objective of this study was to assess the biological activity of essential oils (EOs) of four Juniperus species obtained via two different distillation methods and their potential as biopesticides. The studied factors were juniper species (Juniperus communis L., J. oxycedrus L., J. pygmaea C. Koch., and J. sibirica Burgsd), plant sex (male (M) and female (F)), and distillation method (hydrodistillation via a standard Clevenger apparatus (ClevA) and semi-commercial (SCom) steam distillation). The hypothesis was that the EO will have differential antioxidant, antimicrobial, and insecticidal activities as a function of plant species, plant sex, and distillation method. The two distillation methods resulted in similar EO composition within a given species. However, there were differences in the EO content (yield) due to the sex of the plant, and also differences in the proportions of some EO components. The concentration of α-pinene, ß-caryophyllene, δ-cadinene and δ-cadinol was dissimilar between the EO of M and F plants within all four species. Additionally, M and F plants of J. pygmaea, and J. sibirica had significantly different concentrations of sabinene within the respective species. The EOs obtained via ClevA extraction showed higher antioxidant capacity within a species compared with those from SCom extraction. All of the tested EOs had significant repellent and insecticidal activity against the two aphid species Rhopalosiphum padi (bird cherry-oat aphid) and Sitobion avenae (English grain aphid) at concentrations of the EO in the solution of 1%, 2.5%, and 5%. The tested EOs demonstrated moderate activity against selected pathogens Fusarium spp., Botrytis cinerea, Colletotrichum spp., Rhizoctonia solani and Cylindrocarpon pauciseptatum. The results demonstrate that the standard ClevA would provide comparable EO content and composition in comparison with SCom steam distillation; however, even slight differences in the EO composition may translate into differential bioactivity.

Essential Oil Composition and Bioactivity of Two Juniper Species from Bulgaria and Slovakia.

Juniperus excelsa M. Bieb and J. sabina L. contain essential oil (EO), while J. sabina also contains podophyllotoxin, which is used as a precursor for anti-cancer drugs. Two studies were conducted. The first assessed the variability in the EO profile and podophyllotoxin concentration of the two junipers, depending on the location and tree gender. The main EO constituents of J. excelsa were α-cedrol, α-limonene and α-pinene, while the constituents in J. sabina were sabinene, terpinen-4-ol, myrtenyl acetate and α-cadinol. The podophyllotoxin yield of 18 J. sabina accessions was 0.07-0.32% (w/w), but this was not found in any of the J. excelsa accessions. The second study assessed the effect of hydrodistillation (Clevenger apparatus) and steam distillation (in a semi-commercial apparatus) on the EO profile and bioactivity. The extraction type did not significantly alter the EO composition. The EO profiles of the two junipers and their accessions were different and may be of interest to the industry utilizing juniper leaf EO. Breeding and selection programs could be developed with the two junipers (protected species) in order to identify chemotypes with (1) a high EO content and desirable composition, and (2) a high concentration of podophyllotoxin in J. sabina. Such chemotypes could be established as agricultural crops for the commercial production of podophyllotoxin and EO.

Effects of variety, storage container, and duration on the physical properties, oil content, germination capacity, and seed loss due to Plodia interpunctella infestation of Ethiopian sesame.

BACKGROUND: Owing to fluctuations of international market prices and excess supply during peak harvesting seasons, farmers and traders often suffer from a low market price of sesame. Such a negative impact can be ameliorated by taking advantage of times with a better market price during the off season. This study aimed to investigate the impact of different storage containers on gravimetric properties and germination capacities of five different sesame varieties as well as their impact on Indian meal moth (Plodia interpunctella). RESULTS: There were differences among the types of storage containers in terms of moisture content, oil content, thousand seed weight, and germination capacity with the storage duration. However, in terms of bulk density, true density, and porosity, the results were consistent. On average, a few losses in thousand seed weight for varieties stored in Purdue Improved Crop Storage bags (1.7%), metal silos (2.4%), and GrainPro bags (3.4%) were observed during 12 months' storage compared with polypropylene bags (17%). The difference among sesame varieties in terms of weight loss and loss of webbing due to P. interpunctella varied with storage duration. On average, about 9.4% weight loss and 5.7% loss due to webbing was measured for seed stored in polypropylene bags due to the natural infestation of P. interpunctella. No pest was found in hermetic containers. CONCLUSION: In general, to fetch better market prices, the use of hermetic storage is more efficient to maintain the desired gravimetric properties and to prevent losses due to P. interpunctella infestation compared with the commonly used woven polypropylene bags. © 2020 Society of Chemical Industry.

Grinding and Fractionation during Distillation Alter Hemp Essential Oil Profile and Its Antimicrobial Activity.

The hypothesis of this study was that we can modify the essential oil (EO) profile of hemp (Cannabis sativa L.) and obtain fractions with differential composition and antimicrobial activity. Therefore, the objective was to evaluate the effects of grinding of hemp biomass before EO extraction and fractionation during distillation on EO profile and antimicrobial activity. The study generated a several EO fractions with a diversity of chemical profile and antimicrobial activity. The highest concentrations of ß-pinene and myrcene in the EO can be obtained in the 5-10 min distillation time (DT) of ground material or in the 80-120 min DT of nonground material. High δ-3-carene and limonene EO can be obtained from 0-5 min DT fraction of nonground material. High eucalyptol EO can be sampled either in the 0-5 min DT of the ground material or in the 80-120 min of nonground material. Overall, the highest concentrations of ß-caryophyllene, α-(E)-bergamotene, (Z)-ß-farnesene, α-humulene, caryophyllenyl alcohol, germacrene D-4-ol, spathulenol, caryophyllene oxide, humulene epoxide 2, ß-bisabolol, α-bisabolol, sesquiterpenes, and cannabidiol (CBD) can be obtained when EO is sampled in the 80-120 min DT and the material is nonground. Monoterpenes in the hemp EO can be increased twofold to 85% by grinding the material prior to distillation and collecting the EO in the first 10 min. However, grinding resulted in a slight but significant decrease in the CBD concentration of the EO. CBD-rich oil can be produced by collecting at 120-180 min DT. Different EO fractions had differential antimicrobial activity. The highest antimicrobial activity of EO fraction was found against Staphylococcus aureus subsp. aureus. THC-free EO can be obtained if the EO distillation is limited to 120 min. The results can be utilized by the hemp processing industry and by companies developing new hemp EO-infused products, including perfumery, cosmetics, dietary supplements, food, and pharmaceutical industries.

Industrial, CBD, and Wild Hemp: How Different Are Their Essential Oil Profile and Antimicrobial Activity?

Hemp (Cannabis sativa L.) is currently one of the most controversial and promising crops. This study compared nine wild hemp (C. sativa spp. spontanea V.) accessions with 13 registered cultivars, eight breeding lines, and one cannabidiol (CBD) hemp strain belonging to C. sativa L. The first three groups had similar main essential oil (EO) constituents, but in different concentrations; the CBD hemp had a different EO profile. The concentration of the four major constituents in the industrial hemp lines and wild hemp accessions varied as follows: ß-caryophyllene 11-22% and 15.4-29.6%; α-humulene 4.4-7.6% and 5.3-11.9%; caryophyllene oxide 8.6-13.7% and 0.2-31.2%; and humulene epoxide 2, 2.3-5.6% and 1.2-9.5%, respectively. The concentration of CBD in the EO of wild hemp varied from 6.9 to 52.4% of the total oil while CBD in the EO of the registered cultivars varied from 7.1 to 25%; CBD in the EO of the breeding lines and in the CBD strain varied from 6.4 to 25% and 7.4 to 8.8%, respectively. The concentrations of δ9-tetrahydrocannabinol (THC) in the EO of the three groups of hemp were significantly different, with the highest concentration being 3.5%. The EO of wild hemp had greater antimicrobial activity compared with the EO of registered cultivars. This is the first report to show that significant amounts of CBD could be accumulated in the EO of wild and registered cultivars of hemp following hydro-distillation. The amount of CBD in the EO can be greater than that in the EO of the USA strain used for commercial production of CBD. Furthermore, this is among the first reports that show greater antimicrobial activity of the EO of wild hemp vs. the EO of registered cultivars. The results suggest that wild hemp may offer an excellent opportunity for future breeding and the selection of cultivars with a desirable composition of the EO and possibly CBD-rich EO production.

Essential Oil Yield and Composition of the Balkan Endemic Satureja pilosa Velen. (Lamiaceae).

Satureja pilosa Velen. senso lato is a Balkan endemic plant that is not well characterized and is found on rocky outcrops of limestone base in Stara Planina (the Balkan Mountains) and the Rhodope Mountains. The objective of this study was to assess the variability of essential oil (EO) content and composition of S. pilosa collected at 33 locations across the Balkan and Rhodope Mountains in Bulgaria using advanced statistical methods including cluster analysis. The EO content in dried aboveground biomass varied from 0.52% to 2.03%. More than 21 EO constituents were identified, belonging to the groups of monoterpenes and sesquiterpenes. The monoterpenes were the predominant class, comprising 84.8% to 96.1% of the total EO. Thymol and carvacrol were the major constituents of the phenolic monoterpenoids. Thymol varied from 36.6% to 67.1% and carvacrol varied from 52.4% to 93.0% of the total oil. p-Cymene also varied widely, from 9.6%-34.0%. There were significant variations between locations and within a location in the EO content and composition. This study identified several chemotypes: (1) thymol and p-cymene; (2) thymol, p-cymene and γ-terpinene; (3) carvacrol and p-cymene; (4) carvacrol, p-cymene and γ-terpinene; and (5) carvacrol. This is the first comprehensive study on the endemic plant S. pilosa that identified several chemotypes based on the EO composition. The S. pilosa EO from the five different chemotypes exhibited larvicidal and mosquito repellent activity against Aedes aegypti. The identified chemotypes can be utilized for the development of new varieties with desirable compositions to meet specific industry needs and new mosquito management control products.

Utilization of Nutmeg (Myristica fragrans Houtt.) Seed Hydrodistillation Time to Produce Essential Oil Fractions with Varied Compositions and Pharmacological Effects.

The intent of this study was to utilize distillation timeframes (DT) of nutmeg (Myristica fragrans) essential oil (EO) to generate fractions with differential chemical compositions and bioactivity. Ten fractions were captured at the following distillation timeframes: 0.0-0.5, 0.5-1.0, 1.0-2.5, 2.5-5.0, 5.0-10, 10-30, 30-60, 60-90, 90-120, and 120-240 min. In addition, a control EO was collected from a straight 0-240 min non-stop distillation. ANOVA and advanced regression modeling revealed that the produced EO fractions possess substantial variation in the concentration of potentially desired compounds. The concentrations (%) of α-phellandrene, 3-carene, p-cymene, limonene, α-thujene, α-pinene, camphene, sabinene, ß-pinene, and myrcene decreased, while the concentrations (%) of α-terpinene, γ-terpinene, terpinolene, and myristicin increased in later DT fractions. Nutmeg EO showed some antimalarial activity against Plasmodium falciparum D6, but did not exhibit significant antifungal activity. In general, nutmeg seed oil yields increased with an increase of DT. These results may be utilized by industries using nutmeg EO.

Essential Oil Composition of Ruta graveolens L. Fruits and Hyssopus officinalis Subsp. aristatus (Godr.) Nyman Biomass as a Function of Hydrodistillation Time.

The aim of this study was to establish the kinetics regression models for yield and composition of Ruta graveolens fruit and Hyssopus officinalis subsp. aristatus aboveground biomass essential oil (EO), collected at different time intervals during the hydrodistillation process. The hypothesis was that collecting the EO fractions during specific time frames may result in EOs with dissimilar composition that may have differential use by the industry. Furthermore, we calculated the kinetics regression models for the composition of EO, isolated by hydrodistillation in a Clevenger-type apparatus and characterized by GC-MS and GC-FID analyses. The EO yield of R. graveolens fruits was 0.39% (relative area % of GC-FID chromatogram), with major constituents in the Control fraction (0-90 min) being 2-nonanone, 2-undecanone, and 2-undecanol, representing 65% of the total oil. The highest concentration of 2-nonanone (60%) was found in the 30-60 min oil fraction, the concentration of 2-undecanone (35%) was highest in the Control (0-90 min) fraction, and the concentration of eucalyptol (19%) was highest in the 5-10 min fraction. The EO yield of H. officinalis subsp. aristatus dried biomass was 1.12%. The major constituents in the Control fraction (0-90 min) of H. officinalis biomass were eucalyptol, α-pinene, sabinene, ß-pinene, and cis-3-pinanone, representing 86% of the total. Eucalyptol (58%) was the highest in the 0-5 min fraction. The highest ß-pinene (15%) and cis-3-pinanone (20%) contents were found in the 20-40 min fraction. The kinetics regression models that were developed for EO composition of R. graveolens were second-order polynominal, Michaelis-Menten, and Exponential decay, while for EO composition of H. officinalis subsp. aristatus biomass were Exponential decay and Power. The results from this study could benefit the EO industry.

Hydrodistillation Extraction Kinetics Regression Models for Essential Oil Yield and Composition in Juniperus virginiana, J. excelsa, and J. sabina.

The chemical profile and antioxidant capacity of Juniperus virginiana, J. excelsa, and J. sabina essential oil (EO) fractions as a function of time was the subject of this study. The hypothesis was that, capturing EO in sequential timeframes during hydrodistillation would generate fractions containing unique compositions and antioxidant capacity. In J. virginiana, the highest limonene (43%) was found in the 0⁻5 min oil fraction, with safrole (37%) being highest in the 10⁻20 and 20⁻40 min fractions, and elemol (34%) being highest in the 160⁻240 min fraction. In J. excelsa, α-pinene (34-36%) was the highest in the 0⁻5 min fraction and in the control (non-stop 0⁻240 min distillation) oil, limonene (39%) was the highest in the 0⁻10 min fractions and cedrol (50-53%) was the highest in the 40⁻240 min fractions. In J. sabina, sabinene (80%) was highest in the 0⁻3 min fraction. The highest antioxidant capacity of J. virginiana was demonstrated by the 5⁻10 min fraction; the one in J. sabina by the 3⁻10 min fraction; and, the one in J. excelsa, by the control. The kinetics regression models that were developed can predict EO composition of the three juniper species eluted at different timeframes. Various industries could benefit from the results from this study.

Method for Attaining Caraway Seed Oil Fractions with Different Composition.

Caraway (Carum carvi L.) is a medicinal and aromatic plant; its seeds (fruits) are used as spice and they contain essential oils. We hypothesized that by collecting caraway oil at different time points during the extraction process, we could obtain oil fractions with distinct chemical composition. A hydrodistillation time (HDT) study was conducted to test the hypothesis. The caraway seed oil fractions were collected at eight different HDT (at 0 - 2, 2 - 7, 7 - 15, 15 - 30, 30 - 45, 45 - 75, 75 - 105, and 105 - 135 min). Additionally, a non-stop HD for 135 min was conducted as a control. Most of the oil was eluted early in the HD process. The non-stop HDT treatment yielded 2.76% oil by weight. Of the 24 essential oil constituents, limonene (77 - 19% of the total oil) and carvone (20 - 79%) were the major ones. Other constituents included myrcene (0.72 - 0.16%), trans-carveol (0.07 - 0.39%), and ß-caryophyllene (0.07 - 0.24%). Caraway seed oil with higher concentration of limonene can be obtained by sampling oil fractions early in HD process; conversely, oil with high concentration of carvone can be obtained by excluding the fractions eluted early in the HD process. We demonstrated a method of obtaining caraway seed oil fractions with various and unique composition. These novel oil fractions with unique composition are not commercially available and could have much wider potential uses, and also target different markets compared to the typical caraway essential oil.

Chemical profile, antioxidant and antimicrobial activity of Pinus heldreichii Christ. Distributed in Bulgaria.

Pinus heldreichii Christ. (Bosnian pine), a Tertiary relict and Balkan sub-endemic, has not been comprehensively studied for its essential oil (EO) profile and bioactivity of its different plant parts. This study aimed to determine the EO yield, composition and antimicrobial activity from different parts of P. heldreichii at three different populations (mountains) in Bulgaria. Furthermore, the study assessed the antioxidant activities of plant tissue, including leaves (needles), twigs wood, male and female cones. The EOs yield from different plant parts ranged from 0.09 % (leaves) to 0.74 % (wood of twigs), with monoterpenes being the predominant class. Limonene, α-pinene, ß-caryophyllene, germacrene D, ß-pinene, and ß-myrcene were detected in the EO extracted from all analyzed trees. However, these compounds were not found in the EO extracted from all plant parts of the same trees. Four chemical groups (chemotypes) were identified for EO from twigs, and three chemotypes were identified for EO from leaves. The chemotypes were based on the percent ratio of the main EO constituents (>5 %). Leaves tissue showed the highest values in terms of polyphenols and flavonoids, as well as higher ABTS radical scavenging activity, while the highest antimicrobial activity against Staphylococcus aureus subsp. aureus was seen in the EOs obtained from twigs. This is the first study to identify several chemotypes based on leaf and twigs EO of P. heldreichii distributed in Bulgarian flora. Furthermore, the EO of twigs tips (TT), male cones (MC), and wood of one-two-year-old twigs (WT) of the same trees were reported for the first time. The total polyphenol, flavonoid content, and radical scavenging activity of tissues of annual twigs wood and biennial twigs wood, leaf tissue, MC tissue, and the twigs tips tissue is also reported for the first time in the accessible literature. These findings highlight the potential of P. heldreichii to provide EOs with varying compositions and bioactivities, making them suitable for nutraceutical, pharmacological, and potentially food additive applications. Furthermore, the identification of chemotype accessions in this study suggests their selection for the development of new forest crop as a source for natural products with desirable composition and bioactivity.

Chemical profile of Juniperus excelsa M. Bieb. essential oil within and between populations and its weed seed suppression effect.

The aims of this study were to (1) establish the intrapopulation and seasonal variation of Juniperus excelsа essential oil (EO); (2) compare the J. excelsa concrete and resinoid composition with its EO composition; and (3) investigate the potential herbicidal activity of J. excelsa EO against seeds of Papaver rhoeas L., Consolida orientalis (J.Gay) Schrödinger, Anthemis arvensis L., Avena fatua L., and Agrostemma githago L. Four independent studies were performed to meet these objectives. Twenty-eight individual trees were analyzed from two populations to establish intrapopulation and interpopulation variability of EOs yield and composition. In the seasonal dynamic study of leaf EO, samples from the same three trees and in the same population were collected in January, March, May, July, October, and December and their EO yield and composition determined. The EOs (intrapopulation and seasonal) were extracted by hydrodistillation, while the EO for the herbicidal test was obtained by steam distillation in a semi-commercial (SCom) apparatus. Overall, the EO yield varied significantly from 0.93% to 2.57%. α-Pinene (8.85-35.94%), limonene (11.81-50.08%), and cedrol (3.41-34.29%) were the predominant EO compounds in all samples (intrapopulation variability); however, trans-2,4-decadienol and ß-caryophyllene were predominant in some individual trees. Four chemical groups were identified in the samples collected from two natural populations (intrapopulation). This is the first report on the compositions of J. excelsa concrete and resinoid. Cedrol (15.39%), 7-hydroxy-4-methyl-coumarin (17.63%), 1-octacosanol (36.85%), tritriacontane (16.08%), and tiacontanoic acid were the main compounds in the concrete and resinoid. Juniperus excelsa EO suppressed seed germination and seedling growth of P. rhoeas, C. orientalis, A. arvensis, A. fatua, and A. githago, demonstrating its potential to be used for the development of new biopesticides. The highest EO yield with high content of limonene and cedrol was obtained from samples harvested during the winter months (December, January, and March).