Essential Variability Research Articles

Analysis of chemical and genetic variability in wild hop (Humulus lupulus L.) populations of Kosovo.

Hops is an economically important species due to its diverse secondary metabolites and extensive use in the brewing and medicinal industries. Although hops is widely distributed in Kosovo, the chemical composition of its essential oils and genetic variability of wild populations remain understudied. Therefore, this study aimed to evaluate the chemical and genetic variability of Kosovo's wild hop population using essential oil constituents and microsatellite (simple sequence repeat - SSR) markers. Female hop inflorescences were collected from 21 wild populations in Kosovo. Essential oils were extracted from the dried plant material using a Clevenger apparatus. Chemical composition of the essential oils was analysed using GC-FID-MS. DNA was extracted from dried leaves, and 15 SSR markers were used for fragment analysis. The main constituents of the essential oil were myrcene, α-humulene, (E)-β-farnesene, α-selinene, β-selinene, and E-caryophyllene. Statistical analyses based on chemical composition of essential oils and SSR markers highlighted the low variability among populations and high variability within populations. These findings provide valuable insights for developing strategies for potential use and conservation of wild hop populations in Kosovo, laying the groundwork for future research and comparison with commercial cultivars to assess their breeding potential.

Glandular Trichomes and Essential Oils Variability in Species of the Genus Phlomis L.: A Review.

The genus Phlomis is one of the largest genera in the Lamiaceae family and includes species used since ancient times in traditional medicine, as flavoring for food and as fragrance in cosmetics. The secretory structures (represented by glandular trichomes) as well as the essential oils produced by them constitute the subject of this review. While representatives of this genus are not typically regarded as large producers of essential oils compared to other species of the Lamiaceae family, the components identified in their essential oils and their biological properties necessitate more investigation of this genus. A comprehensive analysis of the specialized literature was conducted for each of the 93 currently accepted species to identify all the results obtained by researchers regarding the secretory structures and essential oils of this genus up to the present time. Glandular trichomes, still insufficiently studied, present morphological peculiarities that differentiate this genus within the family: they are of two categories: capitate (with a wide distribution in this genus) and dendroid. The peltate trichomes, characteristic of many species of this family, are absent. The essential oils from the species of the genus Phlomis have been much more widely studied than the secretory structures. They show considerable variability depending on the species and the environmental conditions.

BERNN: Enhancing classification of Liquid Chromatography Mass Spectrometry data with batch effect removal neural networks

Liquid Chromatography Mass Spectrometry (LC-MS) is a powerful method for profiling complex biological samples. However, batch effects typically arise from differences in sample processing protocols, experimental conditions, and data acquisition techniques, significantly impacting the interpretability of results. Correcting batch effects is crucial for the reproducibility of omics research, but current methods are not optimal for the removal of batch effects without compressing the genuine biological variation under study. We propose a suite of Batch Effect Removal Neural Networks (BERNN) to remove batch effects in large LC-MS experiments, with the goal of maximizing sample classification performance between conditions. More importantly, these models must efficiently generalize in batches not seen during training. A comparison of batch effect correction methods across five diverse datasets demonstrated that BERNN models consistently showed the strongest sample classification performance. However, the model producing the greatest classification improvements did not always perform best in terms of batch effect removal. Finally, we show that the overcorrection of batch effects resulted in the loss of some essential biological variability. These findings highlight the importance of balancing batch effect removal while preserving valuable biological diversity in large-scale LC-MS experiments.

Essential oil variability of Thymus persicus (Ronniger ex Rech.f.) Jalas (Lamiaceae) during in vitro regeneration and ex situ domestication

ABSTRACT Thymus persicus (Lamiaceae) is a range-restricted endemic medicinal and aromatic plant from northwest of Iran. Due to the medicinal importance and over-exploitation of the plant from its natural habitats, conservationand ex situ cultivation of the plant is needed. In the present study, essential oil variability of the plant during its in vitro conservation including in vitro regenerated plant (RP) and acclimated plant (AP) was assessed by GC-FID and GC-MS, and compared with those of growing wild plant (WP). In total, 44, 25 and 25 compounds representing 98.5%, 98.7% and 98.1% were identified in the oils of WP, RP and AP, respectively. The major identified components in the oils were 4,8-β-epoxy-caryophyllene (2.3–10.7%), α-terpineol (9.5–39.2%), linalool (5.7–15.7%) and thymol (2.6–32.8%). In vitro RP with the highest content of thymol had the greatest distance with WP. The AP was also significantly dominated with a large difference in α-terpineol.

Essential Oil Variability of Azorean Cryptomeria japonica Leaves under Different Distillation Methods, Part 2: Molluscicidal Activity and Brine Shrimp Lethality

This study reports on the in vivo molluscicidal activity and Artemia salina lethality of Azorean Cryptomeria japonica leaf (CJL) essential oils (EOs) obtained by hydrodistillation (HD) and water-steam distillation (WSD) techniques, especially in light of the recent focus on the use of forestry and wood industry residues in a sustainable world economy. Molluscicidal activity was performed during several life stages of Radix peregra by the immersion method, under laboratory conditions. A first screening through a single-dose bioassay revealed that both EOs were highly active towards eggs, juveniles and adult snails (ca. 100% mortality). Concentration- and time-toxicity assays were carried out only on adult snails to determine the lethal parameters (LC50;90 and LT50;90). The LC50 values were 33 and 62 µg/mL for EO–WSD and EO–HD, respectively, after 48 h. The LT50 of EO–WSD required only 21 h for both 16 h and continous exposure periods, while that of EO–HD was slighty superior (21.8–25.6 h). Although not significant, EO–WSD was also slightly more toxic against A. salina than EO–HD (LC50 = 98 and 115 µg/mL after 24 h, respectively). In conclusion, Azorean CJL EOs, which are rich in α-pinene (mostly EO–WSD), have huge potential to be used as safe raw materials for the development of natural molluscicide products to control snails responsible for transmitting fascioliasis.

Correspondence between the Compositional and Aromatic Diversity of Leaf and Fruit Essential Oils and the Pomological Diversity of 43 Sweet Oranges (Citrus x aurantium var sinensis L.).

Orange (Citrus x aurantium var sinensis) is the most widely consumed citrus fruit, and its essential oil, which is made from the peel, is the most widely used in the food, perfume, and cosmetics industries. This citrus fruit is an interspecific hybrid that would have appeared long before our era and would result from two natural crosses between mandarin and pummelo hybrids. This single initial genotype was multiplied by apomictic reproduction and diversified by mutations to produce hundreds of cultivars selected by men essentially based on phenotypic characteristics of appearance, spread of maturity, and taste. Our study aimed to assess the diversity of essential oil composition and variability in the aroma profile of 43 orange cultivars representing all morphotypes. In agreement with the mutation-based evolution of orange trees, the genetic variability tested with 10 SSR genetic markers was null. The oils from peels and leaves extracted by hydrodistillation were analyzed for composition by GC (FID) and GC/MS and for aroma profile by the CATA (Check All That Apply) method by panelists. Oil yield varied between varieties by a factor of 3 for PEO and a factor of 14 for LEO between maximum and minimum. The composition of the oils was very similar between cultivars and was mainly dominated by limonene (>90%). However, small variations were observed as well as in the aromatic profile, with some varieties clearly distinguishing themselves from the others. This low chemical diversity contrasts with the pomological diversity, suggesting that aromatic variability has never been a selection criterion in orange trees.

Exploring the Ecological Preferences and Essential Oil Variability in Wild-Growing Populations of the Endangered Local Greek Endemic Thymus holosericeus (Lamiaceae).

Thymus holosericeus Čelak. (Lamiaceae) is a taxonomically isolated and endangered local endemic thyme species which is geographically isolated in four Ionian Islands (West Greece). The present study investigated the essential oil (EO) composition, the ecological preferences, and their correlations in three T. holosericeus wild-growing populations from Zakynthos (ΤH-Z), Cephalonia (ΤH-C) and Lefkada (ΤH-L). The variations in essential oil yield and the composition of T. holosericeus populations were evaluated using hydrodistillation, GC/MS, TLC and NMR analysis. The climatic conditions of each sample were organized and analyzed in RStudio with the raster package and in SPSS with Pearson's Canonical Correlation Analysis (CCA), respectively. The aerial parts of the plants varied in EO yields from 1.92 to 2.28% w/v. The analysis of EO constituents revealed noteworthy qualitative and quantitative inter-population variation. The composition of EOs revealed the presence of linalool (82.77%) and borneol (5.95%) as major compounds in ΤH-Z, while carvacrol (35.34%), geraniol (23.98%), linalool (14.37%), borneol (5.66%), thymol (4.27%) and p-cymene (4.08%) were the main compounds in ΤH-C and linalool (40.37%), geraniol (39.42%) and borneol (5.20%) were dominant components in ΤH-L. The results of the gas chromatography procedure have also been confirmed by 1H and 13C-NMR and TLC analysis. The ecological profile showed an average annual precipitation of 942 ± 18.33 mm and the temperature limits in which T. holosericeus seems to adapt to are 6.80± 1.08 °C 27.70 ± 0.70 °C. Regarding the examined samples, TH-C was adapted to the driest summer and coldest winter conditions, TH-Z was adapted to the lowest annual precipitation with the most complex climatic conditions, and TH-L was adapted to the highest summer temperatures with the lowest precipitation in the wettest period of the year. For each sampled population, the CCA identified the association of the samples' EOs composition with the prevailing local environmental conditions.

Essential Oil Content and Composition of the Chamomile Inflorescences (Matricaria recutita L.) Belonging to Central Albania

The chamomile drug (Chamomillae anthodium) is widely known and has been used as a medicine for ages. Today, the drug is officially registered in the European Pharmacopoeia. Despite the economic importance of the chamomile Matricaria recutita L., little is known about the extent and nature of the essential oil variability and composition of this species in Albania. Therefore, information about the extent of the uses of various gene pools is extremely valuable for the development of future chamomile cultivation and breeding programs. This study aimed to analyze the differences among 29 populations in different sites in central Albania. The quantities of essential oils ranged from a low of 0.10 ± 0.01% in Fier and Tirana to a high of 0.75 ± 0.05% in Linzȅ. The yield of volatile oils depended on the geography, altitude, and other factors, including stress influences on the site of plant population growth. This fact was confirmed by various subclimatic characteristics obtained from individual localities. Essential oil extracted from chamomile inflorescences was recorded to have between 23 and 43 chemical components. It was found that /-/-α-bisabololoxides B and A were the major constituents in 25 samples, with only 4 having dominant /-/-α-bisabolol. The uniquely determined chemical type of the chamomile wild populations in Albania was chemical type B (/-/-α-bisabololoxide B > /-/-α-bisabololoxide A > /-/-α-bisabolol). Based on the study of chamomile’s pharmacodynamic properties, the sesquiterpenes /-/-α-bisabolol and chamazulene are considered to be the most valuable constituents. Consequently, a very intensive improvement breeding program must begin, with emphasis on drug yield, polyploidization, essential oil quantity, and both component contents in the oil.

Elemental Composition of Particulate Matter in the Euphotic and Benthic Boundary Layers of the Barents and Norwegian Seas

The increasing influence of Atlantic inflows in the Arctic Ocean in recent decades has had a potential impact on regional biogeochemical cycles of major and trace elements. The warm and salty Atlantic water, entering the Eurasian Basin through the Norwegian Sea margin and the Barents Sea, affects particle transport, sink, phyto-, and zooplankton community structure and could have far-reaching consequences for the marine ecosystems. This study discusses the elemental composition of suspended particulate matter and fluffy-layer suspended matter derived from samples collected in the Barents Sea and northern Norwegian Sea in August 2017. The mosaic distribution of SPM elemental composition is mainly determined by two factors: (i) The essential spatial variability of biological processes (primary production, abundance, and phytoplankton composition) and (ii) differences in the input of terrigenous sedimentary matter to the sea area from drainage sources (weak river runoff, melting of archipelago glaciers, etc.). The distribution of lithogenic, bioessential, and redox-sensitive groups of elements in the particulate matter was studied at full-depth profiles. Marine cycling of strontium in the Barents Sea is shown to be significantly affected by increasing coccolithophorid bloom, which is associated with Atlantic water. Mn, Cu, Cd, and Ba significantly enrich the suspended particulate matter of the benthic nepheloid layer relative to the fluffy layer particulate matter within the benthic boundary layer.

Children’s Exposure to Radon in Schools and Kindergartens in the Republic of Moldova

This work presents the results from measurements of radon concentrations in primary and high school education institutions—including their gymnasiums—from the Chisinau municipality and various rayons from the central and southern part of the Republic of Moldova. In the research carried out during the years of 2013–2014 and 2021, there were 78 (29 + 49) premises included, respectively, and 149 and 23,805 investigations were performed using RTM-1642 (active measurements) and RadonEye+2 devices (passive measurements). The results show an essential variability for the studied radio-stressogenic factor, depending on the geological conditions of the location of the premises and the age of the building. Thus, during 2013–2014, the minimum concentration of radon detected was 26 Bq m−3, and the maximum detected was 607 Bq m−3. In 2021, the results denote an indicator variability in the range of 17.4–657.9 Bq m−3 for early education institutions, with an average value of 127.6 Bq m−3, and denote a range of 231.8–1129.3 Bq m−3, with an average value of 665.4 Bq m−3), for high school education institutions and their gymnasiums. The effective annual dose for the children in a classroom varies between an interval of 0.21–4.88 mSv y−1 (average 1.19 mSv y−1) and 0.14–9.08 mSv y−1 (average 1.29 mSv y−1) for the 2013–2014 and 2021 surveys, respectively.

Essential Oil Variability of Superior Myrtle (Myrtus communis L.) Accessions Grown under the Same Conditions.

Myrtle (Myrtus communis L., Myrtaceae) has numerous applications in pharmacology, food technology, and cosmetic industry. The current research aimed at measuring variations in the leaf essential oil (EO) compositions of 14 superior myrtle accessions originating in natural habitats of south Iran. The plants were grown under greenhouse conditions. Fresh leaf samples were harvested in June 2021. Based on dry matter, the extractable amount of EO in the accessions ranged from 0.42% (BN2) to 2.6% (BN5). According to GC/MS analysis, the major compounds in the EO were α-pinene (2.35-53.09%), linalyl acetate (0-45.3%), caryophyllene oxide (0.97-21.8%), germacrene D (0-19.19%), α-humulene (0-18.97%), 1,8-cineole (0-18.0%), limonene (0-17.4%), and p-cymene (0-13.2%). These myrtle accessions were classified into four groups, including I: caryophyllene oxide/germacrene D/α-humulene/methyl eugenol chemotype; II: α-pinene/p-cymene/α-humulene and (E)-β-caryophyllene; III: α-pinene/1,8-cineole, and linalool; IV: linalyl acetate/γ-terpinene/1,8, cineole/limonene. These classifications were established by considering the main EO components using hierarchical cluster analysis (HCA) and principal component analysis (PCA). In summary, this study provided new insights into available opportunities of selecting suitable genotypes for commercial cultivation purposes and planning breeding programs in the future.

Essential Oil Chemotypes and Genetic Variability of Cinnamomum verum Leaf Samples Commercialized and Cultivated in the Amazon.

Cinnamomum verum (Lauraceae), also known as "true cinnamon" or "Ceylon cinnamon" has been widely used in traditional folk medicine and cuisine for a long time. The systematics of C. verum presents some difficulties due to genetic variation and morphological similarity between other Cinnamomum species. The present work aimed to find chemical and molecular markers of C. verum samples from the Amazon region of Brazil. The leaf EOs and the genetic material (DNA) were extracted from samples cultivated and commercial samples. The chemical composition of the essential oils from samples of C. verum cultivated (Cve1-Cve5) and commercial (Cve6-c-Cv9-c) was grouped by multivariate statistical analysis of Principal Component Analysis (PCA). The major compounds were rich in benzenoids and phenylpropanoids, such as eugenol (0.7-91.0%), benzyl benzoate (0.28-76.51%), (E)-cinnamyl acetate (0.36-32.1%), and (E)-cinnamaldehyde (1.0-19.73%). DNA barcodes were developed for phylogenetic analysis using the chloroplastic regions of the matK and rbcL genes, and psbA-trnH intergenic spacer. The psbA-trnH sequences provided greater diversity of nucleotides, and matK confirmed the identity of C. verum. The combination of DNA barcode and volatile profile was found to be an important tool for the discrimination of C. verum varieties and to examine the authenticity of industrial sources.

Essential Oil Variability in Iranian Populations of Heracleum persicum Desf. ex Fischer: A Rich Source of Hexyl Butyrate and Octyl Acetate.

Heracleum persicum Desf. ex Fischer seeds are a rich source of essential oils (EOs) with high antimicrobial and antioxidant effects. In order to determine the phytochemical variability in various Iranian H. persicum populations, seed samples were collected from 10 different climatic locations. The current study indicated that hexyl butyrate (20.9–44.7%), octyl acetate (11.2–20.3%), hexyl-2-methylbutyrate (4.81–8.64%), and octyl 2-methyl butyrate (3.41–8.91%) were the major components of the EOs. The maximum (44.7%) and the minimum (20.9%) content of hexyl butyrate were obtained from Kaleibar and Sari populations, respectively. Moreover, the octyl acetate content ranged from 2% (in Mahdasht) to 20.3% in Torghabeh population. The CA and PCA analysis divided the 10 Iranian H. persicum populations into three major groups. Populations from Khanghah, Kaleibar, Shebeilo, Showt, Mahdasht, and Amin Abbad showed a distinct separation in comparison with the other populations, having high contents of hexyl butyrate (39.8%) and low contents of octyl acetate (13.5%) (Chemotype II). According to correlation analysis, the highest correlation coefficient was among habitat elevation and hexyl butyrate content. In addition, the mean annual precipitation was negatively correlated with the content of hexyl butyrate. Although octyl acetate content showed high correlation with soil EC and mean annual temperature, it was not statistically significant. In general, in order to have plants with a high content of hexyl butyrate, it is recommended to harvest these plants from regions with high altitude and low rainfall such as Kaleibar.

Essential oil variability in Echinophora cinerea Boiss. wild populations: a narrow- endemic and vulnerable species in Iran

ABSTRACT Echinophora cinerea Boiss. is an vulnerable plant species which is applied as gastrointestinal invigorator and stimulants in traditional medicine. A study was done to investigate the variation of essential oil (EO) composition of this species among seven wild populations distributed in various microclimates of Zagros Mountain, Iran. Based on the gas chromatography analyses, twenty-one constituents were monitored including 98.6–99.2% of the EO compositions. The major chemical components of essential oils were α-phellandrene (23.7–36.2%), α-pinene (9.5–24.8%), β-myrcene (3.3–17.5%), linalool (1.8–6.7%), β-phellandrene (3.4–5.5%), methyl eugenol (1.1–15.1%), citronellol (0.5–6.4%) and verbenone (1.9–4.9%). Classification of populations revealed four main chemotypes. There were a positive and significant correlation between soil organic carbon and α-terpineol and a negative correlation between α-phellandrene and β-phellandrene contents and the soil EC. The observed variability among the studied populations can provide the best source of materials with favorable components for industrial uses and pharmaceutical industries.

A comprehensive study on essential oil compositions, antioxidant, anticholinesterase and antityrosinase activities of three Iranian Artemisia species

Artemisia is one of the most diverse genera in the Asteraceae family. The genus is wildly distributed in Irano-Turanian habitats and includes 34 species in Iran. Here, for the first time the essential oil variability, antioxidants and anti-cholinesterase and anti-tyrosinase activities of extracts of three Artemisia species (A. tournefortiana, A. khorassanica, A. haussknechtii), from different regions of Iran were evaluated. Based on GC–MS analyses, 81.84% to 98.70% of the total oils were identified. Cluster analysis grouped the studied populations in three different chemotypes. The highest and the lowest essential oil contents were observed in A. khorassanica and A. haussknechtii species, respectively. Camphor, en-in-dicycloether, 1,8-cineole and (Z)-β-farnesene were the dominant components of essential oil in investigated ecotypes. The results revealed that the total phenol content was higher in A. tournefortiana collected from Kerman and A. haussknechtii collected from Chaharmahal and Bakhtiari. However, the lowest phenol content was recorded for A. haussknechtii collected from Isfahan province. The highest flavonoids content was found in A. tournefortiana collected from West Azerbaijan and A. khorassanica collected from North Khorasan. The highest FRAP antioxidant activity was observed in A. tournefortiana (Kerman) and the lower amount was in A. haussknechtii collected from Kohgiluyeh and Boyer-Ahmad. The highest antioxidant activity by DPPH method was in A. khorassanica collected from South Khorasan and the lowest activity was in Isfahan's A. haussknechtii. The acetycholine esterase inhibitory activity was higher in A. tournefortiana collected from West Azerbaijan; and the lowest activity was in A. haussknechtii collected from Chaharmahal and Bakhtiari province. The highest tyrosinase inhibitory activity was in A. khorassanica collected from North Khorasan; and the lowest was in A. haussknechtii collected from Chaharmahal and Bakhtiari.

Antibacterial, Antioxidant and Cytotoxic Studies of the Essential Oil and Ethanol Extract of Aerial Parts of Artemisia rutifolia Steph.ex. Spreng

Mongolia is rich in medicinal plants. In recent years, interest in plant-derived food additives has grown. This study was aimed to evaluate antioxidant, cytotoxic activities of aerial parts ethanol extracts from Artemisia rutifolia Steph.ex Spreng grown in Mongolia. The essential oil composition variability of A.rutifolia Steph.ex Spreng aerial parts collected from three different slopes of Kharkhiraa mountain was assessed by gas chromatography mass spectrometry (GC/MS). Chromatographic analysis of A.rutifolia Steph.ex Spreng essential oils showed the predominance of monoterpene hydrocarbons represented mainly by santolina triene, β-myrcene. The antioxidant and cytotoxic activities of the essential oil and ethanol crude extracts were determined by using DPPH and MTT assays. The antioxidant activity of A.rutifolia Steph.ex Spreng ethanol extract is 2.12 times higher than the antioxidant activity of the essential oil. The essential oil of A.rutifolia Steph.ex Spreng with a concentration of 150 mg/ml or 3μg/disk inhibits the growth of S.enterica 9.3 ± 0.76 mm, B.subtillus 10.3 ± 0.58 mm, S.aureus 9.6 ± 1.5 mm and has a moderate bacterial activity. The results clearly showed that the essential oil presented satisfactory cytotoxic activity against two human tumor cell lines HepG2 (human liver cancer cell line); AGS (human stomach cancer cell line). Our work revealed that the ethanol extracts and essential oil of Artemisia ritifolia Steph.ex Spreng grown in Mongolia has potential as sources of new antioxidant, and cytotoxic compounds, respectively. Essential oil of A.rutifolia Steph.ex Spreng contains caryophylline-7.19% and caryophylline oxide-5.82%, so the essential oil at a dose of 25 mg/ ml inhibits the growth of human stomach cancer cell (AGS). The results of the study were certified by the utility model certificate of “Soap Fragrance Elixir” with the registration number 20-003068.

Essential Oil Variability of Azorean Cryptomeriajaponica Leaves under Different Distillation Methods, Part 1: Color, Yield and Chemical Composition Analysis

This study mainly deals with the effect of hydrodistillation (HD) and water-steam distillation (WSD) methods on the color, yield, and chemical profile of the essential oil (EO) from Cryptomeria japonica fresh leaves from São Miguel Island (Azores Archipelago, Portugal). The yields of EO–HD (pale-yellowish) and EO–WSD (colorless) samples were 1.21% and 0.45% (v/w), respectively. The GC–FID, GC–MS, and 13C-NMR analyses of EO–HD vs. EO–WSD revealed (i) a high-content of monoterpenes (72.8% vs. 86.7%), mainly α-pinene (34.5% vs. 46.4%) and sabinene (20.2% vs. 11.6%), and oxygenated mono- and sesquiterpenes (20.2% vs. 9.6%); (ii) similar sesquiterpene (1.6% vs. 1.6%), β-myrcene (5.9% vs. 5.8%), and camphene (3.5% vs. 3.8%) contents; and (iii) significant differences in other classes/components: EO–HD is richer in oxygenated sesquiterpenes (17.1%, mainly elemol (10.4%) and α-eudesmol (3.4%)) and diterpenes (3%; mostly phyllocladene), while EO–WSD is richer in oxygenated monoterpenes (7.2%, mainly terpinen-4-ol (5.4%)), p-cymene (4.4%), and limonene (3.2%). Overall, the color, yield, and quantitative composition of the EO samples studied are strongly influenced by the distillation method. Nonetheless, this C. japonica leaf EO displayed a consistent α-pinene- and sabinene-rich composition. The same chemotype was found in a commercial Azorean C. japonica leaf EO sample, obtained by industrial steam distillation (SD), as well as in Corsica C. japonica leaf EO–HD. Furthermore, the bioactive composition of our EO samples revealed the potential to be used in green plant protection and in the medical, food, cosmetic, and household industries.

VISIT-TO-VISIT GLOMERULAR FILTRATION RATE VARIABILITY AS A PREDICTOR FOR CARDIOVASCULAR AND RENAL OUTCOMES IN ESSENTIAL HYPERTENSION: DATA FROM A GREEK 8-YEAR-FOLLOW-UP STUDY

Objective: Renal dysfunction is related with adverse prognosis in hypertension, however scarce data exist on the predictive value of kidney function variability on cardiovascular and renal outcomes in this setting. This study aims to assess the prognostic role of visit-to-visit glomerural filtration rate (GFR) variability on the incidence of coronary artery disease (CAD), stroke and end-stage renal disease in hypertensive patients. Design and method: We followed 2380 essential hypertensives (mean age 58.9 years, 1240 males, office blood pressure 144/91mmHg) free of cardiovascular disease for a mean period of 8 years. All subjects had at least one annual visit and blood sampling was performed in all visits for GFR estimation. We calculated standard deviation (SD) of mean GFR from visits 6months onward in patients with >or = 5 visits during follow-up. CAD was defined as the history of myocardial infarction or significant coronary artery stenosis revealed by angiography or coronary revascularization procedure, while stroke was defined as rapid onset of a new neurological deficit persisting at least 24 hours unless death supervened confirmed by imaging findings. End-stage renal disease was defined as GFR<15 mL/min/1.73 m2 or the need for long-term dialysis or transplantation. Results: The incidence of CAD, stroke and end-stage renal disease over the follow-up period were 2.8% (n = 68), 1.09% (n = 26) and 0.6% (n = 14). Hypertensives who developed CAD (n = 2312) had at baseline higher left ventricular mass index (115.7 ± 24.6 vs 103.7 ± 27.3 g/m2, p < 0.0001) compared to those who did not, whereas there was no difference with respect to baseline GFR (78 ± 19.6 vs 79.3 ± 18.6 mL/min/1.73 m2 (p = 0.573). In multivariate Cox regression models visit-to-visit glomerular filtration rate predicted end-stage renal disease (hazard ratio = 1.758, p = 0.01) but not CAD and stroke (p = NS for both). Baseline left ventricular mass index independently predicted CAD (hazard ratio = 1.042, p = 0.015) and stroke (hazard ratio = 1.035, p = 0.002). Conclusions: In essential hypertensive patients GFR variability predicts future development of end-stage renal disease but exhibits no independent prognostic value for CAD and stroke. These results suggest that fluctuations of renal function are related with damage at the kidneys and not at the cardiac and cerebrovascular level.

Assessing the Effectiveness of Isolation and Contact-Tracing Interventions for Early Transmission Dynamics of COVID-19 in South Korea.

Recent COVID-19 outbreaks pose serious public health challenges all around the world. South Korea had experienced the early outbreak of the COVID-19 pandemic and implemented early effective interventions. The 2020 COVID-19 outbreak in South Korea showed spatial hot spots and super-spreading events. As a result of these super-spreading events, three huge outbreaks of the COVID-19 have occurred in Korea from February to December 2020. To capture the intrinsic nature of heterogeneity, an agent-based model has been developed focusing on early transmission dynamics of COVID-19 in South Korea. Based on the social empirical contact information of early confirmed cases of COVID-19, we have constructed a scale-free network. Our agent-based model has incorporated essential individual variability such as different contact numbers and infectivity levels. In the absence of vaccines or treatment, contact tracing, case-isolation, quarantine are the most critical interventions to prevent larger outbreaks. First, we investigate the impacts of critical factors on various epidemic outputs such as incidence and cumulative incidence. These critical factors include contact numbers, transmission rates, infectivity of presymptomatic or asymptomatic cases, and contact-tracing with quarantine intervention. Furthermore, the effectiveness of case isolation and contact-tracing (followed by quarantine) is evaluated under various scenarios. Our results indicate that case isolation combined with contact-tracing quarantine is much more effective under a moderate level of n}{}mathcal R_{0}n (smaller transmission rates or contact numbers) and presymptomatic cases. However, the efficacy of interventions reduces significantly for a higher level of n}{}mathcal R_{0}n (larger transmission rates or contact numbers) with a high level of infectivity (in presymptomatic cases). This highlights the key role of efficient contact-tracing and case-isolation to mitigate larger outbreaks or super-spreading events.

Productivity, essential oil variability and antioxidant activity of Ferula assa-foetida L. oleo-gum-resin during the plant exploitation period

ABSTRACT In the present study, productivity, essential oil variability and antioxidant activity of Ferula assa-foetida oleo-gum-resin (OGR) collected at different collection times (July, August, September, and October) were studied by using GC-FID-MS and DPPH assay. The amount of OGR (g/plant) and its oil content significantly affected by the collection time. The highest and the lowest amount of OGR was obtained in September (13.2 g) and July (6.3 g), respectively. The essential oil content (w/w %) was in the order of: July (9.1%)> August (8.2%)> September (7.8%)> October (7.4%). The total number of constituents was 47 in July, 47 in August, 43 in September and 44 in October, representing 97.7%, 98.6%, 96.8%, and 96.8% of the total oil, respectively. α-Pinene (18.2–48.6%), (Z)-propenyl sec-butyl disulfide (9.4–28.8%), β-pinene (6.2–11.5%), bicyclogermacrene (3.3–6.4%), (E)-propenyl sec-butyl disulfide (1.3–5.8%), germacrene D (2.0–3.9%) and (Z)-β-ocimene (1.1–3.6%) were the main components of the OGR oils. The highest radical scavenging (IC50 87.3 ± 5.1 μg/ml) of the collected OGRs was obtained in August.