Melissa Officinalis Research Articles

Dissipation, processing factors and dietary risk assessment of the bioinsecticide abamectin in herbal plants belonging to Lamiaceae family from open field to herbal tea infusion

Abamectin, the mixture of avermectin B1a and B1b, is widely used as a bioinsecticide and is an alternative to chemical pest control from insects. To our knowledge, its behaviour is not fully recognized, especially in herbs. Thus, the objective of this study was to investigate the environmental fate of abamectin in herbal plants belonging to the Lamiaceae family, its dissipation in open field studies laboratory processing treatments and dietary risk assessment. Three medicinally and culinary important species of herbs: Melissa officinalis L., Mentha × piperita L. and Salvia L. were treated with single and double dose than recommended on the label during their cultivation (BBCH 11–29). Residues were monitored using the QuEChERS method followed by the LC-MS/MS. The dissipation pattern of the sum of avermectin B1a and B1b and their persistence were observed 14 d after spraying. Abamectin decline was very rapid in plants and followed the first-order kinetics model. The half-life (t1/2) was in the range of 0.96–1.08 d (single dose) and 0.93–1.02 d (double dose). The pre-harvest intervals (decrease to the level of 0.01 mg kg−1) were 7.29–7.92 d at single and 7.99–8.64 d at double dose application. Herbal infusion preparation in previously washed and dried mint, lemon balm and sage leaves was the key processing step in the removal of abamectin residues. The reduction of initial deposits after single dose treatment was noted up to 65% (PF = 0.35–0.67) and up to 79% after double dose application (PF = 0.21–0.72) in herbal tea. Acute risk assessment of children and adults for the highest residues in EFSA PRIMo model at single and double dose expressed as hazard quotients (HQ) were <1, indicating no risk to humans via consumption of the herbal products. The data provide a better understanding of abamectin behaviour in herbal plants and can help assure herbs' safety for consumers.

Effect of Melissa officinalis on Chemotherapy-Induced Peripheral Neuropathy in Cancer Patients: A Randomized Trial.

Background: Chemotherapy-induced peripheral neuropathy (CIPN) is a significant cancer treatment side effect that can influence both quality of life and treatment course. Melissa Officinalis (MO), due to its high content of flavonoids, has antioxidant, anti-inflammatory, and neuroprotective properties. Materials and Methods: The cancer patients diagnosed with CIPN attended a referral center in Sari (Iran). The hydroalcoholic extract of MO leaves was extracted by the maceration method. The control group received a placebo along with gabapentin as the standard treatment, and the intervention group received 500 mg Melissa officinalis 2 times daily for 3 months plus gabapentin. Patients were evaluated at the baseline and 3 months later, according to Common Terminology Criteria for Adverse Effects (CTCAE) and EORTC QLQ-C30 (Integrated System for Quality of Life Assessment). Results: A total of 40 patients were considered as group D (intervention group), and 35 patients completed the study. Out of 40 subjects in the placebo group (P), 3 patients could not tolerate the drug due to gastrointestinal disturbances. The final values of CTCAE showed a statistically significant difference (p=0.010). Indicators related to the quality of life in both groups showed a significant improvement. In the intervention group, the pain perception and diarrhea experience were significantly reduced. Conclusion: Quality of life indicators were improved by prescribing gabapentin with and without Melissa officinalis. The addition of Melissa officinalis to the chemotherapy regimen may improve diarrhea and pain perception.

Foliar applied potassium nanoparticles (K-NPs) and potassium sulfate on growth, physiological, and phytochemical parameters in Melissa officinalis L. under salt stress.

Salinity stress significantly constrains agricultural productivity and vegetation decline worldwide, particularly in Iran. Potassium, the second most prevalent nutrient in plants, is well known to be essential for cell metabolism. Here, the effects of potassium fertilizer in two biogenic nanoparticles (K-NPs) and conventional (potassium sulfate) forms (0.1 mg/ml) on Melissa officinalis L. under salinity (0, 50, 100, and 150 mM) were investigated. The results demonstrated that stress markers (electrolyte leakage, malondialdehyde, and hydrogen peroxide) increased as salinity levels increased. Plant growth parameters (shoot and root length, fresh and dry weight of shoot and root) and physiological and photosynthetic parameters (stomatal conductance, relative water content, chlorophyll fluorescence, and photosynthetic pigments) were reduced in salinized plants. The highest reduction in fresh weight root, dry weight root, fresh weight shoot, dry weight shoot, root length, and shoot length was recorded under 150 mM NaCl by 30.2%, 51.6%, 30.5%, 24.7%, 26.4%, and 21%, respectively. In contrast, bulk potassium sulfate and K-NPs increased these parameters. Furthermore, K-NPs improved M. officinalis tolerance to NaCl toxicity by enhancing the content of osmolytes such as proline, soluble sugars, and antioxidant enzymes, improving antioxidant contents such as phenols, tannins, anthocyanins, and flavonoids; increasing total protein; and lowering stress markers in plant tissues. Given the results of the physiological, biochemical, and phytochemical parameters obtained from this study, it can be stated that K-NPs, in comparison to the conventional form of potassium fertilizer, exhibit a greater potential to mitigate damages caused by salinity stress in M. officinalis plants.

The Antimicrobial Potency of Mesoporous Silica Nanoparticles Loaded with Melissa officinalis Extract.

Melissa officinalis is an important medicinal plant that is used and studied intensively due to its numerous pharmacological effects. This plant has numerous active compounds with biomedical potential; some are volatile, while others are sensitive to heat or oxygen. Therefore, to increase stability and prolong biological activities, the natural extract can be loaded into various nanostructured systems. In this study, different loading systems were obtained from mesoporous silica, like Mobile Composition of Matter family (MCM) with a hexagonal (MCM-41) or cubic (MCM-48) pore structure, simple or functionalized with amino groups (using 3-aminopropyl) such as triethoxysilane (APTES). Thus, the four materials were characterized from morphological and structural points of view by scanning electron microscopy, a BET analysis with adsorption-desorption isotherms, Fourier-transform infrared spectroscopy (FTIR) and a thermogravimetric analysis coupled with differential scanning calorimetry. Natural extract from Melissa officinalis was concentrated and analyzed by High-Performance Liquid Chromatography to identify the polyphenolic compounds. The obtained materials were tested against Gram-negative bacteria and yeasts and against both reference strains and clinical strains belonging to Gram-positive bacteria that were previously isolated from intra-hospital infections. The highest antimicrobial efficiency was found against Gram-positive and fungal strains. Good activity was also recorded against methicillin-resistant S. aureus, the Melissa officinalis extract inhibiting the production of various virulence factors.

Therapeutic potential of hypnotic herbal medicines: A comprehensive review.

Insomnia affects millions of people worldwide, prompting considerable interest in herbal remedies for its treatment. This review aims to assess the therapeutic potential of such remedies for insomnia by analyzing current scientific evidence. The analysis identified several herbs, including Rosmarinus officinalis, Crocus sativus, Rosa damascena, Curcuma longa, Valeriana officinalis, Lactuca sativa, Portulaca oleracea, Citrus aurantium, Lippia citriodora, and Melissa officinalis, which show promise in improving overall sleep time, reducing sleep latency, and enhancing sleep quality. These plants act on the central nervous system, particularly the serotonergic and gamma-aminobutyric acid (GABA)ergic systems, promoting sedation and relaxation. However, further research is necessary to fully understand their mechanisms of action, optimal dosages, and treatment protocols. Combining herbal medicines with conventional treatments may offer an effective natural alternative for those seeking medication. Nevertheless, individuals should consult their healthcare provider before using herbal remedies for insomnia. While this review provides evidence supporting their use, additional high-quality studies are needed to firmly establish their clinical efficacy.

Quinic and caffeic acids derivatives: Affecting antioxidant capacities and phenolics contents of certain therapeutic and specialty crops employing water and ethanolic extracts

Recently, there has been a growing interest in medicinal and specialty crops due to their high content of health-promoting compounds, such as quinic acid and caffeic acid derivatives. In light of this, the objective of this study was to analyze the levels of caffeic and quinic acid, specifically caffeoylquinic acid derivatives, in water and water-ethanolic extracts obtained from medicinal plants, including chocolate mint (Mentha piperita L), lemon balm (Melissa officinalis), sweet basil (Ocimum basilicum), and sweet potato tops (Ipomoea batatas L. Lam) using high-performance liquid chromatography. The results showed that the water extracts contained significantly higher amounts of caffeoylquinic acid derivatives than the ethanolic extracts. Among the plants tested, sweetpotato leaves exhibited the highest total phenolic acids content (28.60 mg CQA·g−1), followed by lemon balm (14.71 mg CQA·g−1) and chocolate mint (5.49 mg CQA·g−1) in water-ethanolic extracts. The water-ethanolic extracts from sweet potato leaves were particularly rich in caffeoylquinic acids, especially 5-CQA (10.84 ± 0.31 mg CQA·g−1) and 3-CQA (6.69 ± 0.14 mg CQA·g−1), followed by lemon balm (3.81 ± 0.14 and 1.37 ± 0.05 mg CQA·g−1). On the other hand, sweet basil had the lowest content of all compounds (0.41 and 2.29 mg CQA·g−1). Additionally, an identifiable compound, 3, 4, 5 tri-caffeoylquinic acids (2.98 ± 0.09 mg CQA·g−1), was detected only in sweetpotato leaves and not in the other herbs studied. The findings of this study highlight the significant phytochemical properties present in these medicinal plants, which could have potential therapeutic applications for various conditions.

Effect of a nutraceutical combination on sleep quality among people with impaired sleep: a randomised, placebo-controlled trial

In this randomised, placebo-controlled trial, adults with impaired sleep (Pittsburgh Sleep Quality Index ≥ 5) were randomly assigned using a minimization algorithm to receive a formulation containing l-theanine plus lemon balm, valerian, and saffron extracts, or placebo, during 6 weeks. Objective sleep quality parameters were measured using an actigraphy device. We enrolled and randomised 64 individuals, 31 from the active group and 27 from the placebo group completed the 6 week follow-up. Mean sleep efficiency remained unmodified in the active group, and increased by 3% in the placebo group, the between-group difference in the change was not statistically significant (p = 0.49). Total sleep time also improved more with placebo (13.0 vs. 1.33 min, p = 0.66). Time wake after sleep onset (WASO) decreased more in the active group (4.6% vs. 2.4%), but the difference was not significant (p = 0.33). Mean PSQI decreased by 3.11 points (32.3%) in the active group, and by 3.86 points (39.5%) in the placebo group (p = 0.41). SF-36 increased more with placebo (+ 18.3 in active, + 32.1 in placebo, p = 0.68). Salivary cortisol remained unchanged in both groups. No serious adverse events were reported. Among adults with impaired sleep, a nutraceutical combination did not improve objective or subjective sleep parameters more than a placebo infusion.

Sleep Disorder and its Treatment: From Nature to Laboratory

Sleep is the natural cellular repair mechanism to improve and restore central neural mechanism, memory, hormonal imbalance, and finally, cell rejuvenation. Sleep disorder is characterized by insomnia, circadian rhythm disorder (CRD), sleep apnea, narcolepsy, parasomnia, and restless leg syndrome (RLS) or periodic limb movement disorder (PLMD). Both oversleeping and less sleeping are associated with sleep disorders (SD). Anxiety, schizophrenia, weight loss/gain, hypothyroidism, and oxidative stress are the most common outcomes of SD. There is also a genetic explanation behind circadian rhythmicity, circadian disorder, narcolepsy-cataplexy syndrome, fatal familial insomnia, and somnambulism. Excessive work pressure, stress, and consumption of caffeine and alcohol collectively push a person toward sleep deprivation. Anxiety, schizophrenia, weight loss/gain, hypothyroidism, and oxidative stress are the most common outcomes of SD. Adenosine, melatonin, dopamine, serotonin, gamma amino butyric acid (GABA), orexin, and histamine regulate SDs by various pathways. Among natural sources, Centella asiatica, Bacopa monnieri, Acorus calamus, Withania somnifera, Nardostachys jatamansi, Poria cocos is, Valeriana officinalis, Matricaria chamomilla, Lavandula angustifolia, Nelumbo nucifera, Melissa officinalis, Convolvulus pluricaulis, Camellia sinensis, Ziziphus jujube, Datura stramonium, Zhizhipus jujube, Passiflora incarnata, and Moringa oleifera showed remarkable effects on different forms of SDs through GABAA, serotonin, and melatonin receptors. Pramipexole, ropinirole, rotigotine, clonazepam, lorazepam, estazolam, zolpidem, lemborexant, daridorexant, and suvorexant showed its activity in the treatment of SDs as a dopamine agonist, inhibitor of GABAA receptor, dual orexin receptor antagonist, respectively. This article focused on the types of SDs, the effects of SDs on mental health, receptors involved in the sleep cycle, and the impact of natural molecules and synthetic molecules in the management of SDs.

Effects of Melissa officinalis (lemon balm) consumption on serum lipid profile: a meta-analysis of randomized controlled trials

BackgroundAccording to traditional medicine, Melissa officinalis L., (lemon balm) has been known to remove harmful substances from the blood and is considered a cardiac tonic. Therefore, its use as a cardiovascular remedy may explain the lipid-lowering effects of lemon balm. Dyslipidemia can be considered as a significant preventable risk factor for atherosclerosis, coronary heart disease and type 2 diabetes. The present study is the first meta-analysis to investigate the effects of M. officinalis administration on serum levels of high-density lipoprotein cholesterol (HDL), low-density lipoprotein cholesterol (LDL), triglyceride (TG) and total cholesterol (TC).MethodsFrom inception to October 2023, a thorough search through literature was conducted using PubMed, Scopus, and Web of Science. The inclusion criteria of this study were randomized controlled trials, with or without blinding which provided adequate data for each group at the beginning and end of the follow-up period. Meta-analysis was performed on randomized controlled trials using Comprehensive Meta-Analysis (CMA) V4 software. Risk of bias in the selected studies was examined according to the revised Cochrane risk-of-bias tool for randomized trials. Begg’s funnel plot symmetry status, Begg’s rank correlation, and Egger’s weighted regression tests were employed to evaluate potential publication bias.ResultsThe meta-analysis comprised of 5 randomized controlled trials with a total of 302 patients. The findings of the meta-analysis indicated that the consumption of lemon balm had a significant decrease in TG (SMD (95% CI): -0.396(-0.620, -0.173), p-value = 0.001), TC (SMD (95% CI): -0.416 (-0.641, -0.192), p-value < 0.001) and LDL (SMD (95% CI): -0.23(-0.45, -0.008), p < 0.05) levels compared to the placebo group. While it had no statistically significant effect on HDL level (SMD (95% CI): 0.336(-0.091, 0.767), p-value = 0.123). No significant and detectable publication bias was found in the meta-analysis. Additionally, all included clinical studies demonstrated a low risk of bias for missing outcome data and selection of the reported results. The robustness of the results was demonstrated by a sensitivity analysis using the one-study remove method.ConclusionsThe findings of this meta-analysis provide evidence that lemon balm may be administered as a safe and beneficial herbal medicine for reducing TC, TG and LDL levels. According to the pooled results of 5 studies with a total of 302 patients, lemon balm intake had no significant effect on HDL level. This study reinforces the notion that lemon balm may have a substantial impact on serum lipid profile as a potential remedy in cases of dyslipidemia. The main concern of our research is the limited number of eligible studies and the relatively small population size of each individual study. The patients of these studies had different types of diseases and metabolic syndromes. However, the meta-analysis was sufficiently powered to detect the considerable effects of lemon balm in the combined population regardless of type of diseases.

Carbon steel corrosion in HCl in the presence of aqueous extract of Melissa Officinalis

Carbon steel corrosion in HCl in the presence of aqueous extract of Melissa Officinalis

Ethnobotanical Survey on Antidepressive Plants Used for Mood Management in Algeria

AbstractDepression is a mood disorder associated with cognitive decline. To self-medicate, people use medicinal herbs to limit the side effects associated with taking antidepressants, such as addiction, hallucinations, and dizziness. Current research consists of ethnobotanical studies of medicinal plants used to improve depression-related mood disorders, and the socio-economic profiles of people with depression (gender, age, education level…) and information about the listed antidepressant plants (common name, part used…). 129 individuals belonging to some regions of Algeria answered our questionnaire among which 82% are women and 98% are academics. The informants cited 44 species (Mentha spicata with a relative frequency of citation (RFC) =0.69, Chamomilla nobilis RFC=0.49, Aloysia citrodora RFC=0.19, Lavandula officinalis, Melissa officinalis RFC=0.17, Foeniculum vulgare RFC=0.1, Pimpinella anisum RFC=0.09 and Hypericum perforatum RFC=0.07…) belonging to 25 botanical families represented mainly by the Lamiaceae family (38%). Infusion remains the most common method of preparation, and the leaves are the most used part. These plants modulated the depressive state of informants in a similar way to synthetic antidepressants. These plants deserve to be studied for the development of new herbal drugs with acceptable side effects.

Green Solvent Extraction of Antioxidants from Herbs and Agro-Food Wastes: Optimization and Capacity Determination

Herbs and agro-food wastes are rich sources of bioactive compounds vital for organisms and valuable for many fields of industry. Therefore, in this study, green deep eutectic solvents (DESs) such as choline chloride/citric acid (ChCl:CitA), glucose/citric acid (Gu:CitA), glucose/urea (Gu:U), betaine/citric acid (B:CitA), and betaine/urea (B:U) at a molar ratio of 1:1 for ultrasound-assisted extraction (UAE) of antioxidants from four herbs (chamomile—Cha, lemon balm—LB, mint—M, and nettle—N) and two agro-food wastes (buckwheat husk—BH and chokeberry pomace—ChoP) were proposed. The antioxidant capacity (AC) of the obtained extracts was evaluated utilizing three antioxidant assays: cupric reducing antioxidant capacity (CUPRAC = 0.0–429.9 μmol of Trolox (TE)/g); 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS = 0.0–146.5 μmol TE/g); and 2,2-diphenyl-1-picrylhydrazyl (DPPH = 11.9–170.3 μmol TE/g). The LB extracts revealed the highest CUPRAC (59.3–429.9 μmol TE/g), ABTS (30.7–144.3 μmol TE/g), and DPPH (32.6–170.3 μmol TE/g) values. Due to the lowest antioxidant potential of LB extracts prepared using ChCl:CitA (AC = 30.7–59.3 μmol TE/g) and the highest AC demonstrated by extracts based on B:U (AC = 144.3–429.9 μmol TE/g), the UAE conditions using a new DES consisting of ChCl and U were optimized by the Box–Behnken design (BBD). Effects of three independent variables, molar ratios of the ChCl and U (mol/mol), water content (%), and sonication time (t) on the AC of LB extracts were studied by response surface methodology (RSM). The results of principal component analysis (PCA) and hierarchical cluster analysis (HCA) demonstrated that different DESs had great differences in the extraction of antioxidant compounds from herbs and agro-food residues.

Photo-Cross-Linked Nanofibers Containing Melissa Officinalis Extract as a Novel Active Food Packaging: An Eco-Friendly Alternative for Plastic Packaging

Photo-Cross-Linked Nanofibers Containing Melissa Officinalis Extract as a Novel Active Food Packaging: An Eco-Friendly Alternative for Plastic Packaging

DEVELOPMENT OF NEW TYPES OF TEA DRINKS WITH TARGETED PREVENTIVE PROPERTIES

Recently, interest in the production of tea and tea drinks has increased due to its nutritional and medicinal properties. The composition of tea is complex and is still not fully understood. Therefore, the development of new technology of tea and functional tea drinks opens a unique opportunity for domestic manufacturer to produce competitive products.In this study the technology of three types of tea drinks based on raw components of fruits, berries and medicinal plants «Antioxidant», «Immunostimulating», «Cardiovascular» with targeted preventive properties was developed, where the physicochemical, mineral composition and organoleptic parameters were studied.The results of the analysis showed that the highest concentrations of vitamin C (mg/100 g) were found in sea buckthorn fruits (215.7±18.4), black currant fruits (196.5±14.3), melissa leaves (100.1±9.9), lemon peel (90.5±8.4) and Goji berries (49.5±3.8). High β-carotene content (mg/100 g) was observed in Goji berries, lemon balm leaves and sea buckthorn fruits – 91.3±7.6; 47.2±3.6 and 33.7±2.9 mg/100 g, respectively. In addition, fruits, berries and medicinal plants selected as raw components had high levels of flavonoids, xanthophylls, tocopherols, phenolic compounds and other biologically active substances. Cranberry berries (44.8±3.2), Goji berries (31.0±2.6), black tea leaves (25.4±1.9), black currant fruits (21.6±1.2) and peppermint leaves (15.2±1.1) had high levels of total antioxidants (mg/100 g) due to the increased content of catechins, anthocyanins, carotenoids, vitamin C, tannin and bioflavonoids, contributing to the reduction of oxidative stress and protecting cells from the destructive effects of free radicals. Prophylactic tea blends have been studied and shown to have high taste, fine exquisite aroma and actively stimulating and therapeutic properties, according to the created formulations, taking into account antioxidant immunostimulating activity.

USO DE PLANTAS MEDICINAIS DA COMUNIDADE MARRUÁS DO MUNICÍPIO DE CRAÍBAS-AL, COMO FERRAMENTA NA CONSTRUÇÃO DO CONCEITO DE EDUCAÇÃO AMBIENTAL.

Environmental awareness was applied in this work with the aim of instigating environmental awareness in local communities in the Alagoas countryside, with the aim of building, together with the community, a concept of environmental education, using medicinal plants as a tool. For this purpose, visits were made to the target communities, and semi-structured questionnaires were applied, emphasizing the informants' socio-economic data, as well as ethnobotanical data. The study was carried out in the Marruás community, district of Craíbas – AL, between the months of February and October 2010. 100 interviews were carried out with residents, aged 12 to 80, appointed by the community leader. 40 plant species were surveyed, distributed in 35 families. Most interviewees cited Myracrodruon urundeuva Fr. Allem, known as aroeira, as the most used, followed by Melissa officinalis L. (lemon balm) and Cymbopogon citratus (DC) Stapf. (Holy grass). The predominance of leaves (97%) was observed in relation to other vegetative organs, followed by the bark (6%). The local disappearance of some species such as Chenopodium ambrosioides L. (mastruz) and Eucalyptus globulus Labill was recorded. (eucalyptus). The data obtained reveals the need for instructions to promote the sustainable use of medicinal plants in communities like this, creating a perspective of conservation and management of local vegetation.

Improving nitrogen content in soil and lemon balm (Melissa officinalis L.) yield by purple nonsulfur bacteria Rhodopseudomonas palustris in two consecutive seasons.

The study was conducted to assess the effects of nitrogen (N)-fixing purple nonsulfur bacteria (PNSB) Rhodopseudomonas palustris TLS06, VNW02, VNW64, and VNS89 on soil fertility, N uptake, essential oil (EO) content, growth, and yield of lemon balm. The experiment followed a completely randomized block design with 9 treatments and 3 replications. The treatments consisted of (i) applying 100% N as the recommended fertilizer rate (RFR), (ii) applying 85% N as RFR, (iii) applying 70% N as RFR, (iv) applying 55% N as RFR, (v) the treatment ii combined with N-PNSB, (vi) the treatment iii combined with N-PNSB, (vii) the treatment iv combined with N-PNSB, (viii) 0% as RFR combined with N-PNSB, and (ix) 0% N as RFR. The results showed that applying N-PNSB increased the plant height, and the number of primary branches in both seasons. In addition, the treatment without N fertilizer combined with N-PNSB increased stem leaf biomass by 41.2 and 50.3% in both seasons as compared with the treatment without neither N fertilizer nor N-PNSB. For soil properties, among treatments without N fertilizer, the treatment with N-PNSB increased concentrations of NH4+, soluble P, and exchangeable K+ by 41.3, 41.4, and 26.8%, respectively, as compared with the treatment without N-PNSB at the end of the second season. Applying 85% N as RFR combined with N-PNSB had a greater yield by 5.78-11.8% as compared with the treatment with 100% N as RFR, and a greater EO content by 23% as compared with the treatment with 85% N as RFR.

Ozone Treatment as an Approach to Induce Specialized Compounds in Melissa officinalis Plants.

Plants are constantly subjected to environmental changes that deeply affect their metabolism, leading to the inhibition or synthesis of "specialized" compounds, small organic molecules that play a fundamental role in adaptative responses. In this work, Melissa officinalis L. (an aromatic plant broadly cultivated due to the large amounts of secondary metabolites) plants were exposed to realistic ozone (O3) dosages (80 ppb, 5 h day-1) for 35 consecutive days with the aim to evaluate its potential use as elicitor of specialized metabolite production. Ozone induced stomatal dysfunction throughout the whole experiment, associated with a low photosynthetic performance, a decrease in the potential energy conversion activity of PSII, and an alteration in the total chlorophyll content (-35, -36, -10, and -17% as average compared to the controls, respectively). The production of hydrogen peroxide at 7 days from the beginning of exposure (+47%) resulted in lipid peroxidation and visible injuries. This result suggests metabolic disturbance within the cell and a concomitant alteration in cell homeostasis, probably due to a limited activation of antioxidative mechanisms. Moderate accumulated doses of O3 triggered the accumulation of hydroxycinnamic acids and the up-regulation of the genes encoding enzymes involved in rosmarinic acid, phenylpropanoid, and flavonoid biosynthesis. While high accumulated doses of O3 significantly enhanced the content of hydroxybenzoic acid and flavanone glycosides. Our study shows that the application of O3 at the investigated concentration for a limited period (such as two/three weeks) may become a useful tool to stimulate bioactive compounds production in M. officinalis.

An in vitro analysis of an innovative standardized phospholipid carrier-based Melissa officinalis L. extract as a potential neuromodulator for emotional distress and related conditions.

Background: Melissa officinalis L. (MO), commonly known as lemon balm, a member of the mint family, is considered a calming herb. In various traditional medicines, it has been utilized to reduce stress and anxiety and promote sleep. A growing body of clinical evidence suggests that MO leaf extract supplementation possesses considerable neuropharmacological properties. However, its possible mechanism of action largely remains unknown. Objective: In the present in vitro studies, we comparatively investigated the central nervous system (CNS)-calming and antioxidative stress properties of an innovative standardized phospholipid carrier-based (Phytosome™) MO extract (Relissa™) vs. an unformulated dry MO extract. Methods: The neuropharmacological effect of the extract was studied in the anti-depressant enzymes γ-aminobutyrate transaminase (GABA-T) and monoamine oxidase A (MAO-A) assays and SH-SY5Y cells brain-derived neurotrophic factor (BDNF) expression assay. The neuroprotective effect of the extract against oxidative stress was assessed in SH-SY5Y cell-based (H2O2-exposed) Total Antioxidant Status (TAS) and Total Reactive Oxygen Species (ROS) assays. The cytotoxic effect of the extract was evaluated using MTT and LDH assays. The extract antioxidant effect was also evaluated in cell-free chemical tests, including TEAC-ABTS, DPPH, Ferric Reducing Antioxidant Power (FRAP), Oxygen Radical Antioxidant Capacity (ORAC), and Hydroxyl Radical Antioxidant Capacity (HORAC) assays. Results: Relissa™ exhibited high GABA-T inhibitory activity, IC50 (mg/mL) = 0.064 vs. unformulated dry MO extract, IC50 (mg/mL) = 0.27. Similar inhibitory effects were also observed for MAO-A. Relissa™ demonstrated an improved neuroprotective antioxidant effect on SH-SY5Y cells against H2O2-induced oxidative stress. Compared to unformulated dry MO extract, Relissa™ exerted high protective effect on H2O2-exposed SH-SY5Y cells, leading to higher cells BDNF expression levels. Moreover, cell-free chemical tests, including TEAC-ABTS, DPPH radical scavenging, FRAP, ORAC, and HORAC assays, validated the improved antioxidant effect of Relissa™ vs. unformulated dry MO extract. Conclusion: The results of the present study support the neuromodulating and neuroprotective properties of Relissa™, and its supplementation may help in the amelioration of emotional distress and related conditions.

Co-application of titanium nanoparticles and melatonin effectively lowered chromium toxicity in lemon balm (Melissa officinalis L.) through modifying biochemical characteristics.

Chromium (Cr) toxicity can negatively affect plant growth and development, impacting agricultural productivity and posing risks to human health. Metallic nanoparticles (MNPs) such as titanium dioxide (TiO2) and natural growth regulators such as melatonin (MT) become a promising technology to manage heavy metal-contaminated soils and promote safe food production. The present work was conducted to find the effect of foliar application of TiO2 NPs (15 mg L-1) and MT (100 µM) on growth, biochemical attributes, and Cr accumulation in plant tissues of Melissa officinalis L. under Cr toxicity (50 and 100 mg Cr kg-1 soil). The results showed that Cr toxicity led to decreased plant performance, where 100 mg Cr kg-1 soil led to notable decreases in shoot weight (28%), root weight (27%), essential oil (EO) yield (34%), chlorophyll (Chl) a + b (33%), while increased malondialdehyde (MDA, 30%), superoxide dismutase (SOD) activity (51%), and catalase (CAT) activity (122%). The use of TiO2 NPs and MT, particularly their co-application, remarkably reduced Cr toxicity by enhancing plant weight, Chl content, and lowered MDA and antioxidant activity. Total phenolic content (TPC), total flavonoid content (TFC), EO percentage, and rosmarinic acid in plants treated with Cr at 50 mg Cr kg-1 soil and co-application of TiO2 NPs and MT were relatively higher than in other treatments. Under 100 mg Cr kg-1 soil, the synergic effect of TiO2 NPs and MT-enhanced rosmarinic acid content (22%) but lowered Cr accumulation in roots (51%) and shoots (72%). Heat map analysis showed that CAT, SOD, MDA, and EO yield had the maximum variability under Cr, TiO2 NPs, and MT. Exogenous TiO2 NPs and MT can be recommended to modulate Cr toxicity in lemon balm under soil Cr toxicity.

Toxicological safety evaluation of an aqueous lemon balm (Melissa officinalis) extract

Melissa officinalis (lemon balm) has a long history of safe use as an aromatic herb, flavoring, tea, food supplement, and traditional medicine. An aqueous extract of the leaves of M. officinalis is intended for use as a food ingredient, however the existing safety database does not contain any high quality toxicological studies to support safe consumer exposure. Therefore, a standard tier 1 genotoxicity battery (bacterial reverse mutation and in vitro mammalian cell micronucleus tests) and a 90-day repeated dose oral toxicity study in rats were conducted in accordance with GLP and OECD guidelines. The genotoxicity studies confirmed that aqueous lemon balm extract is not genotoxic at up to the highest concentrations tested (5000 μg/plate or 5000 μg/mL). A non-GLP 14-day dose range finding study was conducted prior to the 90-day study to confirm dietary administration of aqueous lemon balm extract at concentrations of 0, 0.5, 1.6, or 5.0%. The 90-day study was conducted using the established dietary concentrations and no test substance-related adverse effects on clinical, hematological, biochemical, macroscopic, or histopathologic parameters were reported. Thus, the no-observed-adverse-effect-level was determined to be at least 3046.1 and 3720.9 mg/kg body weight/day (the highest doses tested) for male and female rats, respectively.