Accumulation of heavy metals in selected medicinal plants

Bioactive profiling of Rumex vesicarius L. from the Hail region of Saudi Arabia: a study on its phytochemical and elemental analysis, antibiofilm, antibacterial, antioxidant properties, and molecular docking analysis

Background

Rumex vesicarius is a wild leafy plant belonging to the family Polygonaceae, renowned for its therapeutic benefits. The genus Rumex comprises approximately 150 species distributed globally.

Objective

The study aimed to investigate the biological activities of R. vesicarius using in vitro and in silico methods.

Methods

Rumex vesicarius was collected from the mountains in Hail and extracted with methanol. The phytochemical composition was qualitatively determined using colorimetric detection methods. Additional analyses included elemental analysis, in silico docking, antioxidant, antibacterial, and anti-biofilm properties.

Results

The extract contained various classes of phytochemicals, including flavonoids, phenolics, tannins, terpenes, and saponins. Sixteen constituents were identified through molecular docking, revealing inhibition against the filamentous temperature-sensitive protein Z (FtsZ), a crucial factor in bacterial cell division. Six compounds exhibited low binding scores ranging from -8.3 to -5.0 kcal/mol, indicating efficient interaction at the active site. Elemental analysis identified 15 elements, with potassium being the most abundant, followed by calcium, aluminum, silicon, iron, phosphorus, sulfur, magnesium, titanium, strontium, zinc, manganese, bromine, and chromium. Antioxidant analysis revealed significant properties at lower concentrations compared to ascorbic acid, butylated hydroxytoluene, and β-carotene. Antibacterial analysis demonstrated inhibitory effects on Bacillus subtilis MTCC121 and Pseudomonas aeruginosa MTCC 741, with inhibition zones of 13.67 ± 1.0 mm and 11.50 ± 1.0 mm, respectively. The MIC and MBC values ranged from 250 to 500 μg/mL. R. vesicarius also exhibited anti-biofilm activity.

Conclusion

Wild-grown R. vesicarius from the mountains of Hail is rich in bioactive phytochemicals and essential minerals, exhibiting notable antioxidant and antibacterial properties.

Polycyclic aromatic hydrocarbon (PAH) accumulation in selected medicinal plants: a mini review

The use of plant-based products in healthcare systems has experienced a tremendous rise leading to a substantial increase in global demand. However, the quality and effectiveness of such plant-based treatments are often affected due to contamination of various pollutants including polycyclic aromatic hydrocarbons (PAHs). Like other plants, medicinal plants also uptake and accumulate PAHs when exposed to a contaminated environment. The consumption of such medicinal plants and/or plant-based products causes negative effects on health rather than providing any therapeutic advantages. Unfortunately, research focusing on PAH accumulation in medicinal plants has received very limited attention. This review discusses a sizable number of literature regarding the concentration of sixteen priority PAH pollutants as recognised by the US Environmental Protection Agency (USEPA) in different medicinal plants. The review also highlights the risk assessment of cancer associated with some medicinal plants in terms of benzo[a]pyrene (BaP) equivalent concentrations.

Investigating the phytoavailability of metals in roots of Croton macrostachyus and Phytolacca dodecandra: induced rhizosphere processes

Medicinal plants are key component of complementary and alternative medicine, and constitute the first therapeutic strategy for majority of the global population, particularly in developing nations. Croton macrostachyus and Phytolacca dodecandra are among such plants, widely used to treat various diseases. The present study aimed at investigating the elemental composition of both plant root samples collected from four districts in the Central Gondar Zone, Northwest Ethiopia. An optimized wet-digestion procedure was applied with 0.5 g of root sample using HNO3: HCl: H2O2 (v/v) in the ratio of 8:2:1 at 240 °C for 3:00 h (for P. dodecandra), and 5:2:2 at 300 °C for 3:00 h (for C. macrostachyus). Then, concentrations of metals in the digested samples were determined using a flame atomic absorption spectrophotometer; and the validity of the optimized procedure was evaluated by spiking experiments. Results showed good accuracy and repeatability of the methods with percent of recoveries ranging from 85 to 103%. The mean concentrations of metals in C. macrostachyus root samples were higher than their P. dodecandra counterparts, and the distribution of metals showed the following decreasing order: Mg > Ca ≈ Fe > Mn > Zn > Cu > Cr. One-way ANOVA revealed no significant differences (p > 0.05) between the mean concentrations of the same metals in both plant root samples, except for Mg and Cr. Correlation matrix, principal component and cluster analyses suggested that accumulation of metals in the root samples originated from both natural and anthropogenic sources. In conclusion, the roots of both medicinal plants contained substantial amounts of metals, thereby serving as valuable sources of essential elements.

Toxicological effects, residue levels and risks of endocrine-disrupting chemicals in Chinese medicine: a review

Traditional Chinese medicine (TCM) that is used worldwide possesses the satisfactory function of disease prevention, treatment and health care, and this natural medicine seems to be favored due to its low side effects. Endocrine disrupting chemicals (EDCs), which exist in all aspects of our lives, may interfere with the synthesis, action and metabolism of human sex steroid hormones, resulting in the development and fertility problems as well as obesity and the disturbance of energy homeostasis. From planting to processing, TCM may be polluted by various EDCs. Many studies pay attention to this problem, but there are still few reviews on the residues and toxicity risks of EDCs in TCM. In this paper, researches related to EDCs in TCM were screened. The possible contamination sources of TCM from planting to processing and its toxic effects were introduced. Moreover, the residues of metals, pesticides and other EDCs in TCM as well as the health risks of human exposure to EDCs through ingestion of TCM materials were reviewed.

Safety of African grown rice: Comparative review of As, Cd, and Pb contamination in African rice and paddy fields

This review aimed to investigate the reported concentrations of arsenic (As), cadmium (Cd), and lead (Pb) in rice cultivated in Africa and African rice paddies compared to other regions. It also aimed to explore the factors influencing these concentrations and evaluate the associated health risks of elevated As, Cd, and Pb exposure. Relevant data were obtained from electronic databases such as PubMed, Scopus, and Google Scholar using specific keywords related to arsenic, cadmium, lead, rice, Africa, paddy, and grain. While the number of studies reporting the concentrations of As, Cd, and Pb in rice and rice paddies in Africa is relatively low compared to other regions, this review revealed that most of the African rice and paddy soils have low concentrations of these metals. However, some studies have reported elevated concentrations of As, Cd, and Pb in paddy fields, which is concerning due to the increased use of agrochemicals containing heavy metals in rice production. Nonetheless, agronomical interventions such as implementing alternate wetting and drying water management, cultivating cultivars with low accumulation of As, Cd, and Pb, amending rice fields with sorbents, and screening irrigation water can limit the bioaccumulation of these carcinogens in paddy fields using phytoremediation techniques. Therefore, we strongly urge African governments and organizations operating in Africa to enhance the capacity of rice farmers and extension officers in adopting approaches and practices that reduce the accumulation of these carcinogenic metals in rice. This is essential to achieve the sustainable development goal of providing safe food for all.

Comparative pharmacokinetics and urinary excretion of arsenic and mercury after oral administration of realgar, cinnabar and AnGongNiuHuang Pill to rats

Realgar- and cinnabar-containing AnGongNiuHuang Pill (AGNHP) is widely used for treating encephalopathy syndrome. However, it raises great safety concerns due to the adverse effects reported by arsenic or mercury poisoning. Although AGNHP has been generally recognized, little is known about the metabolism of arsenic and mercury and their resulting potential health risk in vivo. Thus, comparative pharmacokinetics and urinary excretion of arsenic and mercury were conducted in rats after oral administration of realgar, cinnabar and AGNHP, respectively. The contents of arsenic and mercury in rat blood and urine were determined by hydride-generation atomic fluorescence spectrometry (HG-AFS) after wet digestion. AGNHP significantly reduced the absorption of arsenic in blood and promoted urinary arsenic excretion. Whereas, it increased the blood mercury absorption and reduced urinary mercury excretion. No significant toxicity was observed in the clinical dose range of AGNHP. However, excessive exposure to arsenic and mercury may still pose risks especially by long-term or excessive medication. The results are helpful for the rational clinical applications of realgar- and cinnabar-containing TCMs.

Significance of Arbuscular Mycorrhizal Fungi in Mitigating Abiotic Environmental Stress in Medicinal and Aromatic Plants: A Review

Medicinal and aromatic plants (MAPs) have been used worldwide for thousands of years and play a critical role in traditional medicines, cosmetics, and food industries. In recent years, the cultivation of MAPs has become of great interest worldwide due to the increased demand for natural products, in particular essential oils (EOs). Climate change has exacerbated the effects of abiotic stresses on the growth, productivity, and quality of MAPs. Hence, there is a need for eco-friendly agricultural strategies to enhance plant growth and productivity. Among the adaptive strategies used by MAPs to cope with the adverse effects of abiotic stresses including water stress, salinity, pollution, etc., their association with beneficial microorganisms such as arbuscular mycorrhizal fungi (AMF) can improve MAPs’ tolerance to these stresses. The current review (1) summarizes the effect of major abiotic stresses on MAPs’ growth and yield, and the composition of EOs distilled from MAP species; (2) reports the mechanisms through which AMF root colonization can trigger the response of MAPs to abiotic stresses at morphological, physiological, and molecular levels; (3) discusses the contribution and synergistic effects of AMF and other amendments (e.g., plant growth-promoting bacteria, organic or inorganic amendments) on MAPs’ growth and yield, and the composition of distilled EOs in stressed environments. In conclusion, several perspectives are suggested to promote future investigations.

Metal(loid)s in Common Medicinal Plants in a Uranium Mining-Impacted Area in Northwestern New Mexico, USA

The objective of this study was to determine uranium (U) and other metal(loid) concentrations (As, Cd, Cs, Pb, Mo, Se, Th, and V) in eight species of plants that are commonly used for medicinal purposes on Diné (Navajo) lands in northwestern New Mexico. The study setting was a prime target for U mining, where more than 500 unreclaimed abandoned U mines and structures remain. The plants were located within 3.2 km of abandoned U mines and structures. Plant biota samples (N = 32) and corresponding soil sources were collected. The samples were analyzed using Inductively Coupled Plasma−Mass Spectrometry. In general, the study findings showed that metal(loid)s were concentrated greatest in soil > root > aboveground plant parts, respectively. Several medicinal plant samples were found to exceed the World Health Organization Raw Medicinal Plant Permissible Level for As and Cd; however, using the calculated human intake data, Reference Dietary Intakes, Recommended Dietary Allowances, and tolerable Upper Limits, the levels were not exceeded for those with established food intake or ingestion guidelines. There does not appear to be a dietary food rise of metal(loid) ingestion based solely on the eight medicinal plants examined. Food intake recommendations informed by research are needed for those who may be more sensitive to metal(loid) exposure. Further research is needed to identify research gaps and continued surveillance and monitoring are recommended for mining-impacted communities.

Daily Dose Standardization Based on Essential and Nonessential Trace Element Presence in Berberis baluchistanica Ahrendt Bark, Leaf, and Root

Medicinal plants have great importance to the consumer health, as beside beneficial compounds, plants can accumulate essential and nonessential metals from soil and surrounding environments, leading to consumer health risks. Assuming this, the present study is aimed at evaluating the elemental composition and daily dose standardization based on essential and nonessential trace element presence in of bark, leaves, and roots of Berberis baluchistanica Ahrendt, a common medicinal plant used as a folk medicine in the region. Atomic absorption and flame emission spectroscopy were performed to analyze the presence of essential and nonessential elements manganese (Mn), copper (Cu), lead (Pb), nickel (Ni), iron (Fe), sodium (Na), and potassium (K). Among the essential elements, K was present at high concentrations in the bark ( $8926.98\pm 0.32\mu \text{g}/\text{g}$ ), leaves ( $7922.77\pm 0.42\mu \text{g}/\text{g}$ ), and roots ( $6668.5\pm 0.96\mu \text{g}/\text{g}$ ) of the plant. The estimated concentration of Na was higher in leaves ( $1782.56\pm 0.13\mu \text{g}/\text{g}$ ), followed by roots ( $1089.5\pm 0.71\mu \text{g}/\text{g}$ ) and bark ( $572.8\pm 0.62\mu \text{g}/\text{g}$ ). The Fe concentration varied in the range of $394.7\pm 0.3\mu \text{g}/\text{g}$ in bark, $1298.3\pm 0.54\mu \text{g}/\text{g}$ in leaves, and $1208.9\pm 0.7\mu \text{g}/\text{g}$ in roots. The trace transition element Mn was highest in leaves ( $42.7\pm 0.99\mu \text{g}/\text{g}$ ), followed by roots ( $33.5\pm 0.94\mu \text{g}/\text{g}$ ) and bark ( $22\pm 1\mu \text{g}/\text{g}$ ). The Cu concentration was low, ranging from $20.1\pm 0.63$ to $22.67\pm 0.7\mu \text{g}/\text{g}$ in leaves, bark, and roots. The obtained concentration of nonessential element Pb was relatively lower than the permissible range (10 mgL–1) established by the World Health Organization. The elemental concentrations in all parts were within the set limits for provisional tolerable daily maximum intake (PTDMI) and provisional tolerable weekly intake (PTWI), and the hazard quotient index (HQ) was below 1 for all toxic metals. The micro and macroelemental distribution and the overall medicinal potential of any medicinal plant can be correlated for dose risk estimation, which will be useful in providing knowledge regarding the contraindication associated with folk medicines. In the present study, based on the elemental composition, it was calculated that the daily safe dose for Berberis baluchistanica is approximately 2-5 g/day of raw powder for an adult, which must not be exceeded to this safe range.

Ecological and health risk assessment of heavy metals in soil and Chinese herbal medicines

As medicinal plants can accumulate harmful metals from the native soil, people's consumption of these materials may cause the human body to accumulate toxic metal elements. This has given rise to people's concerns about the quality and safety of Chinese medicinal materials. This research aims to determine the levels of Cr, Ni, Cu, Zn, As, Cd, Hg and Pb in four medicinal plant species (Aster tataricus L.f., Salvia miltiorrhiza Bge, Radix Aucklandiae, Scutellaria baicalensis Georgi) and their native soil. All samples were collected from Qian'an city, beside Yanshan Mountain Range in Tangshan city, east Hebei Province, north China. The contents of heavy metals we detected in the soil conformed to the current limits. However, the Cd and Hg in the soil had a very high potential ecological risk because of their contents higher than the base level of local soil. The contents of Cu, Cd, Hg and Pb in some medicinal herbs exceeded the standards. The content of Cu in Radix Aucklandiae exceeded the standard by 3 times, and others exceeded the standard by less than one time. The comprehensive health risk assessment of heavy metals with chronic non-carcinogenic effects for human body showed that none of the four medicinal herbs can create a health risk. Thus, there is no strong positive correlation between heavy metal pollution in medicinal herbs and that in the native soil. Further research should be investigated to the connection between the heavy metal levels in the soil and plants, and the comprehensive effects of soil, air and irrigation water on heavy metal pollution of Chinese herbal medicines. We also recommend that Chinese herbal medicines should be cultivated and gathered only from controlled or uncontaminated areas.

Nutraceuticals: Transformation of Conventional Foods into Health Promoters/Disease Preventers and Safety Considerations

Nutraceuticals are essential food constituents that provide nutritional benefits as well as medicinal effects. The benefits of these foods are due to the presence of active compounds such as carotenoids, collagen hydrolysate, and dietary fibers. Nutraceuticals have been found to positively affect cardiovascular and immune system health and have a role in infection and cancer prevention. Nutraceuticals can be categorized into different classes based on their nature and mode of action. In this review, different classifications of nutraceuticals and their potential therapeutic activity, such as anti-cancer, antioxidant, anti-inflammatory and anti-lipid activity in disease will be reviewed. Moreover, the different mechanisms of action of these products, applications, and safety upon consumers including current trends and future prospect of nutraceuticals will be included.

Toxic Metals (As, Cd, Ni, Pb) Impact in the Most Common Medicinal Plant (Mentha piperita)

This study aimed to evaluate the behavior of Mentha piperita under Cd, Pb, Ni, and As soil contamination and their transfer from soil in plants as well as translocation in the roots/stems/leaves system compared with a control without metal addition. The mint seedlings were exposed for a three-month period using two metal mixtures in the same concentrations such as AsCd and AsCdNiPb (23.7 mg/kg As, 5 mg/kg Cd, 136 mg/kg Ni, and 95 mg/kg Pb). The results of metal concentration in plants showed that Cd, Ni, and Pb were accumulated in different parts of the plant, except for As. In plants organs, the order of metal accumulation was roots > stems > leaves. No significant impact on the growth, development, and chlorophyll content compared to the control was observed in the first month of exposure. After three months of exposure, phytotoxic effects occurred. Generally, the transfer coefficients and translocation factors values were less than 1, indicating that Mentha piperita immobilized the metals in root. The laboratory experiments highlighted that for a short period of time, Mentha piperita has the capacity to stabilize the metals at the root level and was a metal-tolerant plant when using a garden rich-substrate.

Potential Health Risks of Macro- and Microelements in Commercial Medicinal Plants Used to Treatment of Diabetes

Information on the content of medicinal plants used in the treatment of diabetes is scarce in the literature. The objectives of this study were to determine the levels of macroelements and microelements in three different medicinal plant species including the dry samples and teas from Bauhinia forficata, Eleusine Indica, and Orthosiphon stamineus and assess the human health risks of ingestion of the tea. The content of the dry samples and teas was obtained using the technique of inductively coupled plasma optical emission spectrometry (ICP OES) after microwave digestion procedure. The hazard quotient (HQ) method was used to access the human health risks posed by heavy metal through tea consumption. The results revealed the presence of K, Mg, Na, P, Al, Fe, Zn, Mn, Cu, Ni, and Se in dry samples and plant teas. The dry plants have high concentration of K and P. All dry plants contain Mg, Na, Al, Fe, Mn, Ni, Zn, and Cu above the limit permissible level set by the World Health Organization (WHO). All the hazard index (HI) values in plant teas were found to be within safe limits for human consumption (HI < 1). The plants may have possible action benefits when used in popular medicine. However, the ingestion through capsules prepared by enclosing a plant powder or teas can be harmful to the health of diabetics. The prescription of this plant for the treatment of diabetes should be treated with caution.

A Review of Microfluidic Detection Strategies for Heavy Metals in Water

Heavy metal pollution of water has become a global issue and is especially problematic in some developing countries. Heavy metals are toxic to living organisms, even at very low concentrations. Therefore, effective and reliable heavy metal detection in environmental water is very important. Current laboratory-based methods used for analysis of heavy metals in water require sophisticated instrumentation and highly trained technicians, making them unsuitable for routine heavy metal monitoring in the environment. Consequently, there is a growing demand for autonomous detection systems that could perform in situ or point-of-use measurements. Microfluidic detection systems, which are defined by their small size, have many characteristics that make them suitable for environmental analysis. Some of these advantages include portability, high sample throughput, reduced reagent consumption and waste generation, and reduced production cost. This review focusses on developments in the application of microfluidic detection systems to heavy metal detection in water. Microfluidic detection strategies based on optical techniques, electrochemical techniques, and quartz crystal microbalance are discussed.

Evaluation of Na and K in anti-diabetic ayurvedic medicine using LIBS

Diabetes mellitus, known as diabetes, is a challenging issue, and to control diabetes, a large population is lining toward ayurvedic medicine. In the present study, four brands of anti-diabetic ayurvedic medicines, along with a home remedy, are analyzed using the laser-induced breakdown spectroscopic (LIBS) technique. The study is carried out to know the elements responsible for glycemic potential. The laser-induced breakdown (LIB) spectra elucidate the presence of organic and inorganic elements like Al, Ba, C, Ca, Cu, Fe, H, K, Mg, N, Na, O, Si, Sr, Zn, and the molecular band of CN molecule in medicines. LIBS result also reveals Na and K's distinct concentration, which plays a vital role in diabetes management. The presence of the CN band and organic elements indicate the presence of organic molecular compositions in medicines. For confirmation of organic composition in the drugs, Fourier transform infrared spectroscopy (FT-IR) has been performed. Principal component analysis (PCA) on the LIBS data of the medicines has been used for instant discrimination based on their elemental/molecular compositions.

Comparison of Heavy Metal Content in Artemisia austriaca in Various Impact Zones

A study on Artemisia austriaca of two anthropogenically heavy metal-polluted impact zones of the Rostov region, namely Lake Atamanskoye and Novocherkasskaya Power Station, was conducted. The influence of soil pollution on the Pb, Zn, and Cu accumulation in various organs of A. austriaca, which is widespread in the studied territories, was established. An extremely high level of Zn content (3051 mg/kg) was observed in the soils of the impact zone of Lake Atamanskoe, as well as an excess over the maximum permissible level for Pb and Cu (32 and 132 mg/kg accordingly). The distribution coefficient (DC) of heavy metal translocation showed the highest mobility of Zn (DC ≥ 1 in 9 out of 11 sites) and the smallest of Pb (DC ≥ 1 in 4 out of 11 sites) in plants of the Novocherkasskaya Power Station impact zone. The zone of increased pollution around Lake Atamanskoye was 1.5 km, which was much smaller than the Novocherkasskaya Power Station zone of high pollution (5 km). However, vehicle emissions accumulated in the soil over the past decades had a greater effect on the Pb translocation than atmospheric emissions of the enterprise.

Antioxidant Capacity, Metal Contents, and Their Health Risk Assessment of Tartary Buckwheat Teas

Tartary buckwheat tea (TBT) is the most popular and widely consumed buckwheat product in many countries. However, the perfect quality control standards for TBT were still lacking, and the content of heavy metals in TBT and their health risks to consumers were still unknown. In this research, the total phenolic content, total flavonoid content, and antioxidant capacity as well as six metal contents and their health risks in TBT were detected. The results showed that the total phenolic content, total flavonoid content, and antioxidant capacity varied significantly among different types of TBT. Meanwhile, six metal concentrations in TBT leaves and infusions decreased in the order of Zn, Cu, Cr, Ni, Pb, and Cd. Health risk assessment indicated that the heavy metal intake only from TBT would not cause a noncarcinogenic risk to consumers. However, a strong carcinogenic risk of Cr in TBT for consumers should be paid more attention.

Occurrence and Risk of Metal(loid)s in Thelesperma megapotamicum Tea Plant

This study reports on the harvesting, ingestion, and contamination of American Indian tea Thelesperma megapotamicum grown on the Navajo Reservation in New Mexico. Uranium (U) and co-metal(loid)s (As, Cd, Cs, Mo, Pb, Se, Th, and V) have contaminated local soil and plants. Tea plants were gathered for analysis near U mining impacted areas. The study collected samples of wild tea plants (n = 14), roots (n = 14), and soil (n = 12) that were analyzed with inductively coupled plasma mass spectrometry. Tea harvesting activities, behavior, and ingestion information were collected via questionnaires. Harvesting took place in community fields and near roadways. Results indicate edible foliage concentration levels for Cd exceeded the World Health Organization (WHO) raw medicinal plant permissible level guidelines. Tea samples collected near high traffic areas had significantly greater Cd and Mo concentrations than those collected near low traffic areas (p < 0.001). Tea sample metal(loid) concentration levels ranged from 0.019-7.916 mg/kg. When compared to established food guidelines including the WHO provisional tolerable weekly intake (PTWI), reference dietary intake, recommended dietary allowance, and the tolerable upper limit (UL), Cd exceeded the WHO guidelines but none exceeded the PTWI nor the UL. These findings warrant improved standardization and establishment of universal guidelines for metal(loid) intake in food.

Toxicological Characterization of Six Plants of the Beninese Pharmacopoeia Used in the Treatment of Salmonellosis

Recent studies reported interesting ethnopharmacological, antibacterial, and phytochemical data on some medicinal plants used in the traditional treatment of salmonellosis in Benin. Unfortunately, very little data exists on the toxicity of these species. This study aims to evaluate chemical characteristic of six Benin pharmacopoeial plants used in the traditional treatment of salmonellosis in Benin. The acute toxicity of aqueous and ethanolic extracts of Psidium guajava, Vernonia amygdalina, Cajanus cajan, Phyllanthus amarus, Uvaria chamae, and Lantana camara was evaluated according to OECD Guideline 423 at a single dose of 2000 mg/kg body weight on Wistar rats. Histological sections were performed on the liver and kidneys to confirm hematological and biochemical data. The content of aluminum, chromium, cadmium, copper, iron, lead, zinc, arsenic, selenium, and manganese was measured in 10 mg of each extract by the inductively coupled plasma optical emission spectroscopy (ICPOES) method. The results of our study generally show the absence of significant effect of the extracts on the hematological and biochemical parameters of the rats. However, with the exception of the aqueous and ethanolic extracts of Psidium guajava root and the ethanolic extract of Phyllanthus amarus (P>0.05), all the extracts have a significant effect on the aspartate aminotransferase (ASAT) level, with a variable threshold of significance (0.0001< P ≤ 0.05). No mortalities and no renal histological conditions were recorded in the treated rats. In general, the heavy metal contents of the extracts do not exceed the standards set by the WHO/FDA except for a few extracts. Arsenic was not detected in any extract, while aluminum and chromium were detected at levels above the WHO/FDA standards. On the basis of these data, it appears that the six plants studied do not show any toxicity. In view of the pharmacological and chemical data previously available, these plants are good candidates for the development of improved traditional medicines with antibacterial and particularly anti-Salmonella properties.

Phytochemical and Safety Evaluation of Hydroethanolic Leaf Extract of Tecoma stans (L.) Juss. ex Kunth

Tecoma stans (yellow bell) is a popular ornamental plant mostly found in the tropical regions. It is reported to have significant pharmacological activity and has gained attention by natives of various cultures. This study focused on the phytoconstituents screening, antioxidant activity, and heavy metal analysis as well as the acute and subchronic toxicity of the hydroethanolic leaf extract (TSE) using standard methods. The presence of flavonoids, alkaloids, cardiac glycosides, saponins, coumarins, and terpenoids in the raw leaf of the plant was observed while the hydroethanolic extract contained coumarins, saponins, cardiac glycosides, and flavonoids. The DPPH percentage scavenging activity of the crude extract was 64.32% while the fractions, ethyl acetate (55.26%), methanol (60.72%), and hydro (36.97%.), gave varying activities. The UV-Vis and FT-IR indicated the presence of alcohols, phenols, alkanes, alkenes, carbonyls (general), aliphatic amines, aromatics, ketones, ethers, esters, carboxylic acids, alkyl halides, saturated aliphatic acids, 1° and 2° amines, amides, and α,β-unsaturated aldehydes. The heavy metal analysis showed a high level of iron (Fe) and zinc (Zn) in the raw leaf. The median acute toxicity (LD₅₀) of the extract was determined to be <5000mg/kg body weight in mice. Subchronic use for 28 days resulted in significant weight gain, reduction in platelet levels, decrease in WBCs, and increase in blood glucose compared to the normal. TSE caused no adverse effects on vital organs. No mortality was recorded. The hydroethanolic extract of T. stans could therefore be considered safe in moderate doses.

Accumulation of heavy metals from soil in medicinal plants

Medicinal plants accumulate heavy metals from contaminated soil, and their consumption can cause poisoning. Our objective was to determine the levels of Pb, Cd, Zn, Cu, Fe, and Mn in four medicinal plant species (Achillea millefolium, Hypericum perforatum, Plantago lanceolata, and Urtica dioica) and their native soil, all sampled at a former smelter. The highest soil Cd, Pb, and Zn levels surpassed the maximum allowed limit 75-fold, 48-fold, and 14-fold, respectively. Their soil levels correlated with those in the plants, but this was not the case with Cu, Fe, and Mn. Heavy metal accumulation seems to depend on the plant species, yet even so, medicinal herbs should be cultivated and gathered only from controlled (uncontaminated) areas. Polluted areas should be monitored on a regular basis, while further research should investigate the connection between the heavy metal levels in the soil, their levels available for plants, and the levels extractable from plants.

Contamination of soil and the medicinal plant Phyllanthus niruri Linn. with cadmium in ceramic industrial areas

Phyllanthus niruri is a plant that is used to prevent calcium oxalate crystallisation and to block the stone formation in urolithiasis. Contaminants in the environment can be readily taken up by medicinal plants due to their ability to absorb chemicals into their tissues. If contaminated plants are ingested, they have the potential to negatively affect human and environmental health. The aim of this study was to assess contamination in the soil and the medicinal plant P. niruri by cadmium (Cd) in ceramic industrial areas of Monte Carmelo, Brazil. Soil samples and plant samples (divided in root, shoot and leaves) were collected from a contaminated monitoring site and from a rural area (which was used as a reference site for comparative purposes). The Cd concentrations of the samples were analysed with an atomic absorption spectrometer. P. niruri was found to be sensitive to soil contamination by Cd that was attributed to ceramic industrial emissions. The results revealed that Cd bioaccumulation in the roots and shoots of P. niruri was associated with a significant increase (p < 0.05) in the concentration of active lignan compounds (phyllanthin and hypophyllanthin) in the leaves. The identification of high concentrations of Cd and active lignan compounds suggests a risk of contamination of the site and the risk of a high dose of Cd to people exposed at the site.

Protective Effect of Leaf Ethanolic Extract Etlingera hemisphaerica Blume Against Mercuric Chloride Toxicity in Blood of Mice

This research was intended to investigate the protective effect of leaf ethanolic extract Etlingera hemisphaerica Blume (LE3H) against mercuric chloride (HgCl₂) toxicity in blood of mice (Mus musculus). The experimental animals, 95 male M. musculus, received drink and food ad libitum. Three materials were tested: LE3H (0.13, 0.26, 0.39 mg/g body weight [bw]) was administered by gavage; HgCl₂ (5 mg/kg bw) was administrated by gavage or intraperitoneal injection; and Imunos (the nutritional supplement to stimulate the immune system; 0.2 mg/g bw), as a positive control for LE3H treatment, was given by gavage. Blood samples were taken from the tails for determining number of blood cells. The animals were killed by cervical dislocation (CD), and then blood samples were collected from the hearts for protein electrophoresis. Results revealed the same number of leukocytes with LE3H (0.39 mg/g bw) treatment as with the Imunos treatment. HgCl₂ administration increased leukocytes and decreased erythrocytes; HgCl₂ administration followed by LE3H (0.39 mg/g bw) treatment protected the amount of blood cells as well as the control. HgCl₂ administration showed a new 125 kDa protein and caused overexpression of 48 kDa protein; this protein profile could be protected by LE3H (0.39 mg/g bw) treatment as in the control condition. We conclude that LE3H provides a protective effect against HgCl₂ toxicity in blood of M. musculus.

Indicators of environmental contamination by heavy metals in leaves of Taraxacum officinale in two zones of the metropolitan area of Mexico City

The present study was designed to detect the effect of heavy metals in two zones of the Metropolitan Area of Mexico City (MAMC), the Centro de Ciencias de la Atmósfera (CCA), and the Altzomoni station in the Iztaccíhuatl-Popocatépetl National Park. Taraxacum officinale was selected as the indicator organism of responses to atmospheric contamination by heavy metals. Determinations of heavy metals were performed, and total mRNA was extracted to quantify the expression of microRNA398 (miR398), superoxide dismutase 2 (CSD2), and the amounts of free radicals using the bromide of 3-(4,5-dimethylthiazole-2-ilo)-2,5-diphenyltetrazole (MTT) salts reduction assay. Results from the Altzomoni station showed high concentrations of five heavy metals, especially Aluminum, while three heavy metals were identified in the CCA-UNAM zone, most importantly, Vanadium, both in the dry season; miR398 expression presented subtle changes but was greater in the leaves from the stations with higher concentrations of heavy metals. Observations included a significant expression of CSD2, mainly in the dry season in both study zones, where levels were significant with respect to controls (p < 0.05). Reduced MTT was also higher in the dry season than in the rainy season (p < 0.05). In conclusion, the increase in heavy metals on the leaves of Taraxacum officinale induces increased expression of the CSD2 gene and reduced MTT; thus, they can be used as indicators for biomonitoring heavy metal concentrations.

The Hazard Content of Cadmium, Lead, and Other Trace Elements in Some Medicinal Herbs and Their Water Infusions

54 samples belonging to 23 herbal species (15 individuals and 8 mixtures) were analyzed for their contents of heavy metals in the raw materials and in their water infusions. Trace and toxic elements in these samples were determined by using inductively coupled plasma-atomic emission spectrometry (ICP-OES) following acid digestion. The order of decreasing mean metal concentrations in raw materials (mg/kg) was found to be as follows: Fe (440) > Mn (162) > Zn (45.8) > Cu (12) > Pb (10.4) > Ni (5.4) > Cr (2.9) > Co (0.91) > Cd (0.5). It was found that 21% of the analyzed samples contain both Cd and Pb above their permissible limits. However, the infusions produced from these plants were found to contain fewer amounts of metals than the raw materials. Studied metals had the following mass transfer percentages to the infusion solutions (Fe: 3.5%, Cd: 14%, Cr: 15%, Pb: 20%, Co: 29%, Ni: 31%, Zn: 36%, Cu: 48%, and Mn: 53%). The estimated daily intake calculated for the toxic elements Pb and Cd through the consumption of herbal infusions was far below the tolerable daily intake set by the World Health Organization (WHO).

Monitoring heavy metals, residual agricultural chemicals and sulfites in traditional herbal decoctions

BACKGROUND

Asian traditional herbal preparations are frequently considered for the contamination with undeclared toxic or hazardous substances. The aim of this study was to determine the toxic heavy metals, pesticides and sulfur dioxide in decoctions that is a common form of final utilization in Korea.

METHODS

A total of 155 decoctions composed of multi-ingredient traditional herbs were randomly sampled from Seoul in Korea between 2013 and 2014. For each decoction, the concentrations of four heavy metals (arsenic, cadmium, lead and mercury), 33 pesticides and sulfur dioxide were analyzed using inductively coupled plasma mass spectrometry (ICP-MS), mercury analyzer, gas chromatography/nitrogen phosphorous detector (GC/NPD), gas chromatography/micro electron capture detector (GC/μECD), and Monier-Williams method respectively.

RESULTS

One hundred fifty-two of One hundred fifty-five decoctions (98.1%) contained one of three heavy metals (96.1% for As, 97.4% for Cd, and 90.3% for Pb, 0.0% for Hg). Their average concentrations (77.0 ± 79.7 ug/kg for As, 20.4 ± 23.7 ug/kg for Cd, and 68.8 ± 76.5 ug/kg for Pb) were approximately 20% of the maximum allowable limits of vegetable or ginseng beverage described in the Korean Food Standard Codex while their 95th percentile concentrations were below than the guideline for them. None of 33 pesticides was detected in 155 decoction samples, and only one sample showed over limit of detection for residual sulfites.

CONCLUSIONS

This study support that the contained status of toxic heavy metals, pesticides and sulfur dioxide in herbal decoctions are currently within safe level in Korea, and provide a reference data for the further studies focused on the safety herbal preparations.

Baccharis trimera (Less.) DC as genotoxicity indicator of exposure to coal and emissions from a thermal power plant

During coal combustion, hazardous elements are discharged that impair environmental quality. Plant cover is the first available surface for the atmospheric pollutants in terrestrial ecosystems. The aim of this study was to evaluate genotoxicity in the aqueous extract of the native plant, Baccharis trimera, exposed to coal and emissions from a thermal power plant (coal-fired power plant in Candiota, Brazil), correlating seasonality, wind tunnel predominance, and presence of inorganic elements. The presence of inorganic elements in the aerial parts of B. trimera was analyzed by particle-induced X-ray emission (PIXE) spectrometry, and genotoxicity was evaluated by ex vivo comet assay. The genotoxic effects of aqueous extracts of B. trimera from four sites located in the area around power plant were analyzed by comet assay in peripheral human lymphocytes. Winter samples showed greater levels of metals than summer samples. Genotoxicity was detected in B. trimera extracts collected from the region exposed to extraction and burning coal. Extracts from the site impacted by the dominant wind induced more damage to DNA than those from other sites. Based on our data, we can suggest that in winter the inorganic elements from extraction and burning of coal and carried through the wind tunnel were responsible for the genotoxicity observed in aqueous extract of B. trimera.