How Are Medicinal Plants Useful When Added to Foods?

Trace Element and Mineral Content in Medicinal Plants Collected in the Altai Mountains Foothills

The objective of the present study was to assess the patterns of trace element and mineral accumulation in 21 medicinal plants collected in the Altai Mountains foothills. The levels of trace elements and minerals in Hippophae rhamnoides, Aronia melanocarpa, Sorbus aucuparia, Viburnum opulus, Rosa canina, Crataegus sanguinea (fruits), Chamaenerion angustifolium, Echinacea purpurea, Fagopyrum esculentum, Trifolium pratense, Origanum vulgare, Achillea millefolium, Mentha piperita (herbs), Plantago major, Salvia officinalis, Urtica dioica (leaves), Panax ginseng, Rhaponticum carthamoides, Eleuterococcus senticosus, and Taraxacum officinale (roots), and Matricaria recutita flowers were assessed using inductively-coupled plasma mass-spectrometry. Comparative analysis revealed that R. carthamoides roots accumulated the highest level of toxic trace elements (Al, Cd, Ni, Pb). C. angustifolium herbs and V. opulus fruits are characterized by the highest As and Sn levels, respectively. The highest content of essential trace elements and minerals was observed in H. rhamnoides fruits (Zn), V. opulus fruits (Cu), E. purpurea herbs (I, Mg), R. carthamoides roots (Fe), O. vulgare herbs (Mn), and M. recutita herbs (Se). In turn, R. canina fruits are characterized by the lowest levels of certain essential and toxic trace elements. Significant differences in B, Cr, Li, Si, and Sr content were also revealed. Discriminant analysis revealed complete discrimination of certain medicinal plants based on their trace element and mineral content. The obtained data indicate the potential usefulness of medicinal plants as sources of certain essential trace elements and minerals, as well as provides data for risk assessment of toxic trace element intake following administration of medicinal plants.

Meta-analysis of the anti-oxidative and anti-inflammatory effects of hypoglycaemic plant-derived medicines

BACKGROUND

The pivotal role of oxidative stress and inflammation in the pathophysiology of type 2 diabetes mellitus (T2DM) has been firmly established. However, the evidence concerning hypoglycaemic medicinal plants' antioxidant and anti-inflammatory effects remains inconclusive due to inconsistencies in prior studies. To address this gap, our study aims to perform a comprehensive systematic review and meta-analysis of randomized controlled trials (RCTs) to consolidate previous research findings in this field.

METHODS

We conducted a comprehensive search in the PubMed, Web of Science, Embase, Cochrane Library, and Scopus databases to identify relevant English randomized controlled trials (RCTs). Our study adhered to the Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) guidelines. All eligible studies that evaluated concurrently the antioxidative and anti-inflammatory effects of hypoglycaemic plant-derived supplements on type 2 diabetes mellitus (T2DM) were included in the meta-analysis. The meta-analysis itself was carried out using both fixed and random effects models to synthesize the findings from the selected studies.

RESULTS

Our study included 47 trials with a total of 2636 participants, both male and female, aged between 20 and 79 years, diagnosed with prediabetes, type 2 diabetes mellitus (T2DM), or metabolic syndrome. The meta-analysis revealed that plant-derived treatments, compared to placebos or other medicines, significantly improved oxidative stress (SMD = - 0.36, 95% CI - 0.64 to - 0.09), inflammation (SMD = - 0.47, 95% CI - 0.63 to - 0.31), total antioxidant capacity (SMD = 0.46, 95% CI 0.16-0.75), and antioxidant enzyme activity (SMD = 1.80, 95% CI 1.26-2.33). The meta-regression analysis showed that treatment duration exceeding 8 weeks significantly impacted the heterogeneity of the oxidative stress data.

CONCLUSIONS

Several hypoglycaemic plant-based treatments appear to positively affect T2DM patients by concurrently lowering oxidative stress and inflammatory indicators and boosting antioxidant enzyme activity.

CLINICAL TRAIL REGISTRY

PROSPERO ID: CRD42021226147.

Antioxidant, Antimicrobial, Cytotoxicity, and Larvicidal Activities of Selected Synthetic Bis-Chalcones

Plants are known to have numerous phytochemicals and other secondary metabolites with numerous pharmacological and biological properties. Among the various compounds, polyphenols, flavonoids, anthocyanins, alkaloids, and terpenoids are the predominant ones that have been explored for their biological potential. Among these, chalcones and bis-chalcones are less explored for their biological potential under in vitro experiments, cell culture models, and animal studies. In the present study, we evaluated six synthetic bis-chalcones that were different in terms of their aromatic cores, functional group substitution, and position of substitutions. The results indicated a strong antioxidant property in terms of DPPH and ABTS radical-scavenging potentials and ferric-reducing properties. In addition, compounds 1, 2, and 4 exhibited strong antibacterial activities against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Salmonella enteritidis. The disc diffusion assay values were indicative of the antibacterial properties of these compounds. Overall, the study indicated the antioxidant and antimicrobial properties of the compounds. Our preliminary studies point to the potential of this class of compounds for further in vivo investigation.

An Overview on the Use of Extracts from Medicinal and Aromatic Plants to Improve Nutritional Value and Oxidative Stability of Vegetable Oils

Oil oxidation is the main factor limiting vegetable oils' quality during storage, as it leads to the deterioration of oil's nutritional quality and gives rise to disagreeable flavors. These changes make fat-containing foods less acceptable to consumers. To deal with this problem and to meet consumer demand for natural foods, vegetable oil fabricators and the food industry are looking for alternatives to synthetic antioxidants to protect oils from oxidation. In this context, natural antioxidant compounds extracted from different parts (leaves, roots, flowers, and seeds) of medicinal and aromatic plants (MAPs) could be used as a promising and sustainable solution to protect consumers' health. The objective of this review was to compile published literature regarding the extraction of bioactive compounds from MAPs as well as different methods of vegetable oils enrichment. In fact, this review uses a multidisciplinary approach and offers an updated overview of the technological, sustainability, chemical and safety aspects related to the protection of oils.

Laurus azorica: Valorization through Its Phytochemical Study and Biological Activities

Laurus azorica (Seub.) Franco is an endemic species from the Azores, traditionally used in all the islands as a seasoning in cooking. The studies carried out with this species refer mainly to its essential oils. The study that was developed here allowed, for the first time, to determine the chemical composition and biological activities of the ethanol extract, fractions, and pure compounds from L. azorica. The hexane fraction was analyzed by GC–MS and revealed the presence of 48 compounds, comprising mainly fatty acids, fatty alcohols and terpenes, the family of fatty alcohols identified here for the first time in the genus Laurus. Three sesquiterpene lactones—costunolide, 11,13-dehydrosantonin and reynosin—were isolated for the first time in L. azorica from the same fraction, and structurally characterized using spectroscopic techniques. The compounds identified belong to families known to have relevant medicinal and nutritional properties. Regarding antioxidant activities, the results obtained showed a moderate radical scavenging effect of extracts and fractions, while in the β-carotene bleaching assay, costunolide was shown to be the most active (IC50 = 4.08 ± 0.76 μg/mL), about 3.6 times more active than the standard, gallic acid, which presented IC50 = 14.56 ± 0.13 μg/mL. Although the inhibition of extracellular matrix-degrading enzymes was not detected, the ethanol extract showed good inhibitory activity of tyrosinase, with an IC50 of 12.04 ± 0.23 μg/mL, only 6.6-fold lower than the control kojic acid. The results presented deepen the knowledge about a little studied species, opening new perspectives for the development of value-added applications in the food and cosmeceutical fields.

Chemical Composition, Antioxidant, and Antimicrobial Activity of Dracocephalum moldavica L. Essential Oil and Hydrolate

Steam distillation was used for the isolation of Dracocephalum moldavica L. (Moldavian dragonhead) essential oil (DMEO). This aromatic herbaceous plant is widespread across the Northern Hemisphere regions and has been utilized in health-improving studies and applications. In addition to the DMEO, the hydrolate (DMH), a byproduct of the distillation process, was also collected. The DMEO and DMH were analyzed and compared in terms of their chemical composition, as well as their in vitro biological activities. The main component in DMEO was geranyl acetate, while geranial was dominant in DMH. The DMEO demonstrated better antioxidant and antimicrobial activities compared with the DMH against Staphylococcus aureus, Escherichia coli, Salmonella Typhimurium, and Listeria monocytogenes, which represent sources of food-borne illness at the global level. The DMEO and DMH show promise as antioxidant and antimicrobial additives to various products.