Polyphenol content and biological activities of Ruta graveolens L. and Artemisia abrotanum L. in northern Saudi Arabia

Natural populations of Ruta graveolens L. and Artemisia abrotanum L. in northern Saudi Arabia may be a rich source of natural polyphenols with potential biological activities. Therefore, tentative high-performance liquid chromatography–diode array detection was used to analyze the polyphenol contents of leaf extracts. R. graveolens mainly contained the phenolic acids chlorogenic acid and p-coumaric acid and the flavonoids rutoside and quercetin, whereas those of A. abrotanum mainly contained the phenolic acids isochlorogenic acid and rosmarinic acid and the flavonoid quercetin. Leaf extracts of both species showed antioxidant activities due to the presence of quercetin, chlorogenic acid, and p-coumaric acid as well as antiproliferative and cytotoxic activities against cancer cells, which may be attributed to necrotic cell accumulation during the early and late apoptotic periods. Both species also exhibited antibacterial activity, although the activity was higher in R. graveolens due to the high contents of quercetin and other polyphenols. Finally, both species exhibited antifungal activities, which were associated with specific polyphenols. This is the first study to confirm the richness of polyphenols and wide spectrum of biological activities in natural populations of R. graveolens and A. abrotanum in northern Saudi Arabia

Saudi Rosmarinus offcinalis and Ocimum basilicum L. polyphenols and biological activities

Investigating the polyphenolic profile of natural Rosmarinus offcinalis and Ocimum basilicum populations may reveal essential compounds that have biological activities. Natural populations of R. offcinalis and O. basilicum in Northern Riyadh were investigated by HPLC-DAD analyses. Several polyphenols, including rosmarinic acid, gentisic acid, 3,4-dihydroxyphenylacetic acid, rutoside, and others, out of 38 screened were confirmed. Rosmarinic acid was the major polyphenol in both of R. offcinalis and O. basilicum. R. offcinalis methanolic leaf extracts contained other phenols such as gentisic acid while O. basilicum contained also 3,4-dihydroxyphenylacetic acid and rutoside as well as others. R. o cinalis showed higher antioxidant activities than O. basilicum using 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP), and $\beta$-carotene bleaching assays. These higher activities are associated with a higher composition of rosmarinic acid in leaf extracts. The antioxidant activities of O. basilicum were attributed to identified phenols of rosmarinic acid, 3,4-dihydroxyphenylacetic acid, and rutoside. There were antiproliferative and cytotoxic activities of leaf extracts, as well as identified polyphenols, against several cancer cells. These activities were attributed to the accumulation of necrotic and apoptotic cells in treated cancer cells with leaf extracts as well as identified polyphenols. The antibacterial and antifungal activities of leaf extracts were mainly attributed to 3,4-dihydroxyphenylacetic acid and rutoside in O. basilicum and rosmarinic acid and caffeic acid in R. offcinalis. This study proved that R. offcinalis and O. basilicum natural populations might be considered as promising sources of natural polyphenols with biological activities

Evaluation of Silicon Supplementation for Drought Stress under Water-Deficit Conditions: An Application of Sustainable Agriculture

Drought is a key abiotic stress that confines agriculture development worldwide. Silicon (Si) is commonly considered to be a valuable element for resistance against drought and for sustainable agriculture. To investigate the morpho-physiological and biochemical characteristics of Gerbera jamesonii plants, a pot experiment was conducted under greenhouse conditions and exposed to water stress (60% FC) and well-watered (100% FC) conditions. Foliar application of Si was carried out after ten days (48 days after sowing) of drought treatment and was repeated weekly, while well-water was regarded as control. Water deficiency significantly abridged the morphological attributes, pigments, and stress-related metabolites and negatively affected the photosynthetic apparatus in drought-stressed gerbera plants. However, Si supplementation by 40 mg L-1 produced increased leaf area (31%), stem length (25%), flower diameter (22%), plant fresh biomass (17%), total chlorophyll (48%), and concentration of carotenoids (54%) in water-stressed plants. Similarly, the accretion of a total free amino acid (41%) and the activities of peroxidase, catalase, superoxide dismutase, ascorbate peroxidase, glycinebetaine, total soluble proteins, total free proline, and malondialdehyde were enhanced by 44%, 31%, 53%, 33%, 330%, 61%, 51%, and 66%, respectively, under drought stress in comparison with control conditions. Meanwhile, the photosynthetic rate (89%), the transpiration rate (12%), and stomatal conductance (55%) were significantly enhanced in water-deficit gerbera leaves with Si supplementation. This study proposes that the foliar application of Si is a viable and convenient method of improving the performance of elegant gerbera flower plants in regions of the world that are facing severe water deficiency

Production of verbascoside, isoverbascoside and phenolic acids in callus, suspension, and bioreactor cultures of Verbena officinalis and biological properties of biomass extracts

Callus, suspension and bioreactor cultures of Verbena officinalis were established, and optimized for biomass growth and production of phenylpropanoid glycosides, phenolic acids, flavonoids and iridoids. All types of cultures were maintained on/in the Murashige and Skoog (MS) media with 1 mg/L BAP and 1 mg/L NAA. The inoculum sizes were optimized in callus and suspension cultures. Moreover, the growth of the culture in two different types of bioreactors—a balloon bioreactor (BB) and a stirred-tank bioreactor (STB) was tested. In methanolic extracts from biomass of all types of in vitro cultures the presence of the same metabolites—verbascoside, isoverbascoside, and six phenolic acids: protocatechuic, chlorogenic, vanillic, caffeic, ferulic and rosmarinic acids was confirmed and quantified by the HPLC-DAD method. In the extracts from lyophilized culture media, no metabolites were found. The main metabolites in biomass extracts were verbascoside and isoverbascoside. Their maximum amounts in g/100 g DW (dry weight) in the tested types of cultures were as follow: 7.25 and 0.61 (callus), 7.06 and 0.48 (suspension), 7.69 and 0.31 (BB), 9.18 and 0.34 (STB). The amounts of phenolic acids were many times lower, max. total content reached of 26.90, 50.72, 19.88, and 36.78 mg/100 g DW, respectively. The highest content of verbascoside and also a high content of isoverbascoside obtained in STB (stirred-tank bioreactor) were 5.3 and 7.8 times higher than in extracts from overground parts of the parent plant. In the extracts from parent plant two iridoids—verbenalin and hastatoside, were also abundant. All investigated biomass extracts and the extracts from parent plant showed the antiproliferative, antioxidant and antibacterial activities. The strongest activities were documented for the cultures maintained in STB. We propose extracts from in vitro cultured biomass of vervain, especially from STB, as a rich source of bioactive metabolites with antiproliferative, antioxidant and antibacterial properties

Floristic composition, life history traits and phytogeographic distribution of forest vegetation in the Western Himalaya

IntroductionScientific documentation of the qualitative forest vegetation parameters of a biogeographical area provides baseline information to guide conservation strategies and design policies for biodiversity management regulations.MethodsWe present one of the most comprehensive qualitative vegetation analyses to evaluate the entire structure and function of an ecosystem in the remote northern part of the Kashmir Himalaya, India. Several multivariate ecological community analyses were conducted after determining the presence of plant species in the various habitats using a random sampling technique.ResultsIn total, 155 plant species belonging to 120 genera and 49 families occurred in the area. Asteraceae was the largest family (12% of plant species) followed by Rosaceae (11%). The patterns of species distribution across families were uneven, with 50% of the species belonging to only 7 families, and 23 families being monotypic. In terms of functional groups, the herbaceous growth form dominated. Therophytes were the dominant life form, indicating that the vegetation was disturbed. According to the phytogeographical research, 65% of the species documented in the study area were native, 15% were invasive, 14% naturalized, and 5% being casual. The majority (30%) of exotic species were reported along roadsides. Of all the species found, 39% grew in their natural habitats, such as forests, and 11% were scattered along roadsides. Plant species were grouped in five different clusters based on their floristic similarity. According to the estimated diversity indices, natural forest has the greatest values for Shannon’s and Simpson’s index. We found that the study area serves as the natural habitat for several significant, endangered medicinal plants, including Arnebia benthamii, Bergenia ciliata, Delphinium roylei, Gentiana kurroo, Phytolacca acinosa, Saussurea costus, and Trillium govanianum. Therefore, we recommend that human intervention in natural regeneration efforts be prioritized in these habitats to increase the population of these species.ConclusionExamining species features from the perspective of functional groups contributes to our understanding of the ecological aspects of the flora. It may also be useful in developing management plans to ensure long-term management of forest landscapes in this remote Himalayan region

Large-scale cis- and trans-eQTL analyses identify thousands of genetic loci and polygenic scores that regulate blood gene expression

Trait-associated genetic variants affect complex phenotypes primarily via regulatory mechanisms on the transcriptome. To investigate the genetics of gene expression, we performed cis- and trans-expression quantitative trait locus (eQTL) analyses using blood-derived expression from 31,684 individuals through the eQTLGen Consortium. We detected cis-eQTL for 88% of genes, and these were replicable in numerous tissues. Distal trans-eQTL (detected for 37% of 10,317 trait-associated variants tested) showed lower replication rates, partially due to low replication power and confounding by cell type composition. However, replication analyses in single-cell RNA-seq data prioritized intracellular trans-eQTL. Trans-eQTL exerted their effects via several mechanisms, primarily through regulation by transcription factors. Expression of 13% of the genes correlated with polygenic scores for 1,263 phenotypes, pinpointing potential drivers for those traits. In summary, this work represents a large eQTL resource, and its results serve as a starting point for in-depth interpretation of complex phenotypes

<i>In vitro</i> antioxidant and antiproliferative activities of six international basil cultivars

<div><p>The total phenolic, flavonoid and tannin contents in leaves extracts of <i>Ocimum basilicum</i> (OB) (Lamiaceae) international cultivars, as well as their overall antioxidant activities using DPPH and linoleic acid assays, were investigated. Furthermore, the antiproliferative and cytotoxic activities against line HeLa, MCF-7, Jurkat, HT-29, T24, MIAPaCa-2 cancer cells and one normal human cell line HEK-293 were examined. DPPH and linoleic acid assays ranged from 75.8% to 93.3% and from 74.5% to 97.1%; respectively. <i>O. b.</i> ‘purple ruffle’, <i>O. b.</i> ‘dark opale’, <i>O. b.</i> ‘genovese’, <i>O. b.</i> ‘anise’, <i>O. b.</i> ‘bush green’ and <i>O. b.</i> L. (OBL) varied in their antiproliferative and cytotoxic activities, influenced cell cycle progression and stimulated apoptosis in most cancer cells. OBL exhibited the highest antioxidant and antiproliferative activities. OB extracts not only improve taste but also have certain anticancer activity against diverse cancer cells due to the presence of compounds such as rosmarinic acid, chicoric acid and caftaric acid. Thus, OB represents a potent source of anticancer materials.</p></div

Egyptian herbal tea infusions' antioxidants and their antiproliferative and cytotoxic activities against cancer cells

<div><p>The antioxidant, antiproliferative and cytotoxic activities against different human cancer cells were investigated in local and recently introduced plants of <i>Mentha</i> sp., <i>Rosmarinus officinalis</i> L. (ROL) and <i>Origanum majorana</i> L. (OML). ROL exhibited the highest antioxidant activities (IC₅₀ 8.4 ± 0.2 μg/mL) followed by OML and mint species such as <i>Mentha suaveolens</i> ‘apple mint’ and <i>Mentha longifolia</i> L. exhibiting moderate antioxidant activities. HPLC analysis of leaf extract revealed that rosmarinic acid is the main component followed by caffeic acid. Herbal leaf extracts varied in their proliferation inhibition and cytotoxicity against HeLa, MCF-7 and Jurkat cancer cells in a dose-dependent matter. The highest antiproliferative inhibition and cytotoxic activity were detected in ROL and OML followed by mint. Local herbs might have a potential role as anticancer natural medicines in addition to their high antioxidant activities due to the presence of different phenolics in their aqueous tea extracts.</p></div

Detection of intraocular Leptospira spp. by real‐time polymerase chain reaction in horses with recurrent uveitis in Belgium

Background Equine recurrent uveitis (ERU) has been associated with Leptospira spp. infection. No information exists concerning the prevalence of Leptospira‐associated ERU in Belgium and about the sensitivity of detection of Leptospira in different ocular media. Objectives To establish the prevalence of intraocular Leptospira spp. in ERU‐affected and healthy eyes of horses examined at the Equine Clinic of the University of Liège by real‐time PCR and to compare the results of the aqueous and vitreous humour of the same eye. Study design Cross‐sectional. Methods Sixty‐six eyes from 59 client‐owned horses with a diagnosis of equine recurrent uveitis (ERU‐group) were studied from May 2015 to December 2017. Fifty healthy eyes from 28 euthanised horses for unrelated reasons examined during the same period were included in the control group. Intraocular fluids (aqueous and/or vitreous humours) from ERU‐affected eyes were sampled and analysed by real‐time PCR for Leptospira spp. Aqueous and vitreous humours from the control group were processed in the same way. Results Both groups were comparable regarding age, sex, eye sampled (OS/OD), humours sampled (aqueous/vitreous humour) but not regarding breeds, with an over‐representation of Warmbloods and Appaloosas in the ERU‐group. The prevalence of Leptospira spp. was 30.3% (20/66 eyes) in the ERU‐group. Leptospira spp. DNA was identified in 11 aqueous and 17 vitreous humours with eight horses testing positive in both humours, nine horses testing positive for vitreous humour alone and third horses for aqueous humour alone. The phi‐correlation between aqueous and vitreous humour Leptospira‐PCR results is 0.47 suggesting a low association. All the control eyes were negative. Main limitations The diagnostic method selected for this study (lipL32 qPCR) did not allow identification of the serovars. Conclusions Leptospirosis is a potential cause of ERU in Belgium. Testing both intraocular media is advised whenever possible