Glechoma hederacea L. is a medicinal plant that is known in traditional medicine for its anti-inflammatory, antibacterial, antiviral, and anticancer properties. This study evaluated the potential for commercial production of G. hederacea and compared the chemical composition and activity of 70% ethanol extracts and steam-distilled essential oils from wild-grown and cultivated G. hederacea collected in different harvesting periods. The main compounds identified in the 70% ethanol extracts were phenolic acids (chlorogenic and rosmarinic acids) and flavonoid O-glycosides. The essential oil varied in the three accessions in the range of 0.32–2.98 mL/kg−1 of dry weight. The extracts possessed potent antioxidant and anti-inflammatory properties in LPS-treated bone-marrow-derived macrophages. The results of flow cytometry show that extracts from different vegetation periods reduced the conversion of macrophages to the proinflammatory phenotype M1. The chemical composition varied the most with the different harvesting periods, and the most suitable periods were the flowering and vegetative phases for the polyphenolic compounds and essential oils, respectively. G. hederacea can be successfully grown under organic farming conditions, and cultivation does not significantly affect the chemical composition and biological activity compared to wild-grown plants.

The endangered medicinal plant Eryngium maritimum L. faces significant natural and anthropogenic threats. Therefore, in vitro propagation is recommended for both conservation and commercial purposes. The aim of the study was to develop a series of protocols for seed disinfection, in vitro multiplication and rooting, and ex vitro and field adaptation. For explant disinfection, the length and temperature of three consecutive disinfectants were investigated. Macrosalt modifications of MS medium and plant growth regulator addition to media effect on axillary bud propagation rate and rooting was studied. Survival and leaf growth during ex vitro and field adaptation in response to potting media, pot cell diameter, and light spectrum were tested. Seeds treated with diluted detergent at 40 °C for 180 min, followed by 0.01% KMnO4 for 3 h and commercial bleach for 11 min, achieved a lower rate of contamination and high germination rate. Axillary bud proliferation and rooting were enhanced by reducing nitrogen content in media and adding plant growth regulators. Potting media and pot size affect survival and growth ex vitro. Timely transplantation to field conditions before overwintering increases plantlet survival. In the present work, a suitable foundation is laid to scaleup the production of E. maritimum by micropropagation.

The extensive application of synthetic insecticides and herbicides over the past 50 years has led to a number of problems, including negative effects on non-target organisms and the evolution of pesticide-resistant pests. As an alternative means of pest control, plant-based biopesticides have emerged. While developing a new bioinsecticide, allelopathy on both target pests and target crops must be evaluated. We evaluated volatile organic compounds (VOCs), total phenolic content (TPC), total sugars and antiradical activity (ARA), as well as 18 photosynthetic apparatus characterizing functional parameters as stress signaling response to aqueous caraway seed distillation by-product-based extracts. VOCs were detected by headspace gas chromatography mass spectrometry (HS-GC-MS). The caraway extract application decreased “green leaf volatile” C4, C5 and C6 alcohol content in the cucumber leaves. Total phenolic content (TPC), total sugars and antiradical activity (ARA) using high-throughput 96-well plate spectrophotometric methods were tested in dried leaves. No significant changes in these parameters were detected in cucumber leaves after the application of extracts. The caraway extract application did not cause changes in the functioning of the photosynthesis apparatus. Aqueous caraway seed distillation by-product-based extracts can be considered non-phytotoxic to cucumber plants; however, they modify the VOC emissions even ten days after treatment.

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The common dandelion (Taraxacum campylodes G.E.Haglund) is known for its medicinal properties and as a non-toxic, highly nutritious edible plant. Even though the herb is mostly collected in the wild, the food and pharmaceutical industries prefer cultivated plant material. Cultivation offers the possibility to achieve predictable yields, ensure the botanical identity of the plants and products can be certified according to organic or biodynamic standards; therefore the interest in domestication is growing. Due to the scarcity of research on dandelion cultivation in agricultural systems, the current study focused on determining the quantitative and qualitative characteristics of 13 wild populations from Latvia in an organic farming system. Populations collected at Gluda, Priekuli, Mundigciems, Marupe as well as variety TA008 had the highest dry root weight (>100 g per plant) and exceeded the root weight of variety Nouvelle more than two-fold. The highest concentration of chlorogenic acid (CHA) (0.12%) and chicoric acid (CCA) (0.15%) was found in the wild population collected in Turaida. The wild populations from Marupe and Mundigciems had a high average root weight as well as a relatively high CHA and CCA content, making them suitable for commercial growing. The present study examined the feasibility of cultivating wild dandelion populations in an organic farming system. The results revealed a high degree of variation within and between populations; therefore, dandelion wild populations can be used for domestication, breeding and selection of accessions most suitable for the pharmaceutical or food industries.