Among fungal pathogens, infections by drug-resistant Candida species continue to pose a major challenge to healthcare. This study aimed to evaluate the activity of the bioactive natural product, penta-O-galloyl-β-d-glucose (PGG) against multidrug-resistant (MDR) Candida albicans, MDR Candida auris, and other MDR non-albicans Candida species. Here, we show that PGG has a minimum inhibitory concentration (MIC) of 0.25–8 μg mL–1 (0.265–8.5 μM) against three clinical strains of C. auris and a MIC of 0.25–4 μg mL–1 (0.265–4.25 μM) against a panel of other MDR Candida species. Our cytotoxicity studies found that PGG was well tolerated by human kidney, liver, and epithelial cells with an IC50 > 256 μg mL–1 (>272 μM). We also show that PGG is a high-capacity iron chelator and that deletion of key iron homeostasis genes in C. albicans rendered strains hypersensitive to PGG. In conclusion, PGG displayed potent anti-Candida activity with minimal cytotoxicity for human cells. We also found that the antifungal activity of PGG is mediated through an iron-chelating mechanism, suggesting that the compound could prove useful as a topical treatment for superficial Candida infections.
Streptococcus pneumoniae (pneumococcus) forms organized biofilms to persist in the human nasopharynx. This persistence allows the pneumococcus to produce severe diseases such as pneumonia, otitis media, bacteremia and meningitis that kill nearly a million children every year. While bacteremia and meningitis are mediated by planktonic pneumococci, biofilm structures are present during pneumonia and otitis media. The global emergence of S. pneumoniae strains resistant to most commonly prescribed antibiotics warrants further discovery of alternative therapeutics. The present study assessed the antimicrobial potential of a plant extract, 220D-F2, rich in ellagic acid, and ellagic acid derivatives, against S. pneumoniae planktonic cells and biofilm structures. Our studies first demonstrate that, when inoculated together with planktonic cultures, 220D-F2 inhibited the formation of pneumococcal biofilms in a dose-dependent manner. As measured by bacterial counts and a LIVE/DEAD bacterial viability assay, 100 and 200 µg/ml of 220D-F2 had significant bactericidal activity against pneumococcal planktonic cultures as early as 3 h post-inoculation. Quantitative MIC’s, whether quantified by qPCR or dilution and plating, showed that 80 µg/ml of 220D-F2 completely eradicated overnight cultures of planktonic pneumococci, including antibiotic resistant strains. When preformed pneumococcal biofilms were challenged with 220D-F2, it significantly reduced the population of biofilms 3 h post-inoculation. Minimum biofilm inhibitory concentration (MBIC)50 was obtained incubating biofilms with 100 µg/ml of 220D-F2 for 3 h and 6 h of incubation. 220D-F2 also significantly reduced the population of pneumococcal biofilms formed on human pharyngeal cells. Our results demonstrate potential therapeutic applications of 220D-F2 to both kill planktonic pneumococcal cells and disrupt pneumococcal biofilms.
Background
Ethnoveterinary knowledge is highly significant for persistence of traditional community-based approaches to veterinary care. This is of particular importance in the context of developing and emerging countries, where animal health (that of livestock, especially) is crucial to local economies and food security. The current survey documents the traditional veterinary uses of medicinal plants in the Lesser Himalayas-Pakistan.
Methods
Data were collected through interviews, focus groups, participant observation, and by administering questionnaires. A total of 105 informants aged between 20–75 years old who were familiar with livestock health issues (i.e. farmers, shepherds, housewives and herbalists) participated in the study.
Results
A total of 89 botanical taxa, belonging to 46 families, were reported to have ethnoveterinary applications. The most quoted families were Poaceae (6 taxa), Fabaceae (6), Asteraceae (5), and Polygonaceae (5). Adhatoda vasica was the most cited species (43%), followed by Trachyspermum ammi (37%), and Zanthoxylum armatum var. armatum (36%). About 126 medications were recorded against more than 50 veterinary conditions grouped into seven categories. The highest cultural index values were recorded for Trachyspermum ammi, Curcuma longa, Melia azedarach, Zanthoxylum armatum var. armatum and Adhatoda vasica. The highest informant consensus factor was found for pathologies related to respiratory and reproductive disorders. Comparison with the local plant-based remedies used in human folk medicine revealed that many of remedies were used in similar ways in local human phytotherapy. Comparison with other field surveys conducted in surrounding areas demonstrated that approximately one-half of the recorded plants uses are novel to the ethnoveterinary literature of the Himalayas.
Conclusion
The current survey shows a remarkable resilience of ethnoveterinary botanical knowledge in the study area. Most of the species reported for ethnoveterinary applications are wild and under threat. Thus, not only is it imperative to conserve traditional local knowledge of folk veterinary therapies for bio-cultural conservation motives, but also to assist with in-situ and ex-situ environmental conservation initiatives, which are urgently needed. Future studies that focus on the validation of efficacy of these ethnoveterinary remedies can help to substantiate emic concepts regarding the management of animal health care and for rural development programs.
Keywords: Medicinal plants; Ethnobotany; Ethnoveterinary; Lesser Himalayas; Pakistan
Background: Plant material from different organs of Pistacia terebinthus L., (Anacardiaceae) were collected in Kosovo with aim to analyze the chemical variability of the essential oils among native populations and to test them for potential antibacterial activity against Staphylococcus aureus. Methods: Essential oils obtained from leaves, pedicels, fruits and galls were analyzed by GC-FID and GC/MS. Minimum inhibitory concentration (MIC) against three clinically relevant strains of S. aureus (NRS385, LAC and UAMS-1) were used to evaluate the antibacterial activity of essential oils. Results: In total, 33 different compounds were identified. The main constituents were α-pinene (12.58-66.29 %), D-limonene (13.95-46.29 %), β-ocimene (0.03-40.49 %), β-pinene (2.63-20.47 %), sabinene (0.00-5.61 %) and (Z)-β-ocimene (0.00-44.85 %). Antibacterial testing of the essential oils against three clinical isolates of S. aureus revealed that seven of the eight samples had some activity at the concentration range tested (0.04-0.512 % v/v). The gall tissues from both sites produced the highest yield of essential oil (3.24 and 6 %), and both exhibited growth inhibitory activity against S. aureus. The most bioactive essential oils, which exhibited MIC90 values ranging from 0.032-0.128 % v/v, obtained from the fruits of the Ura e Shejtë collection site. Likewise, the leaf and pedicel essential oil from the same site was highly active with MIC90 values of 0.064-0.128 and 0.032-0.256 % v/v, respectively. Conclusions: Principle Component Analyses demonstrated that there is a variation in the chemical composition of essential oil depending on the plant organs from which essential oil are obtained and the geographical origin of the plant populations. The highest variability regarding the chemical composition of essential oil was found between oils obtained from different organs originating from the Prizren site. The MIC90 activity of Pistacia terebinthus was on par or superior compared with Tea Tree Oil control (0.128 % v/v), suggesting that essential oils from this species may have some potential for development as an antibacterial agent for S. aureus infections.
Background: Kosovo represents a unique hotspot of biological and cultural diversity in Europe, which allows for interesting cross-cultural ethnobotanical studies. The aims of this study were twofold: 1) to document the state of traditional knowledge related to local (esp. wild) plant uses for food, medicine, and handicrafts in south Kosovo; and 2) to examine how communities of different ethnic groups in the region (Albanians, Bosniaks/Gorani, and Turks) relate to and value wild botanical taxa in their ecosystem.
Methods: Field research was conducted in 10 villages belonging to the Prizren municipality and 4 villages belonging to the Dragash municipality, located in the Sharr Mountains in the southern part of Kosovo. Snowball sampling techniques were used to recruit 139 elderly informants (61 Albanians, 32 Bosniaks/Gorani and 46 Turks), for participation in semi-structured interviews regarding the use of the local flora for medicinal, food, and handicraft purposes.
Results: Overall, we recorded the local uses of 114 species were used for medicinal purposes, 29 for food (wild food plants), and 20 in handicraft activities. The most important species used for medicinal purposes were Achillea millefolium L., Sambucus nigra L., Urtica dioica L., Tilia platyphyllos Scop. Hypericum perforatum L., Chamomilla recutita (L.) Rauschert, Thymus serpyllum L. and Vaccinium myrtillus L. Chamomilla recutita was the most highly valued of these species across the populations surveyed. Out of 114 taxa used for medicinal purposes, only 44 species are also included in the European Pharmacopoeia. The predominantly quoted botanical families were Rosaceae, Asteraceae, and Lamiaceae. Comparison of the data recorded among the Albanian, Bosniak/Gorani, and Turkish communities indicated a less herbophilic attitude of the Albanian populations, while most quoted taxa were quoted by all three communities, thus suggesting a hybrid character of the Kosovar plant knowledge.
Conclusion: Cross-cultural ethnobiological studies are crucial in the Balkans not only for proposing ways of using plant natural resources, which could be exploited in sustainable local development projects (e.g. focusing on eco-tourism and small-scale trade of medicinal herbs, food niche and handicrafts products), but also for fostering collaboration and reconciliation among diverse ethnic and religious communities.
Background: Ethnoveterinary medicine is a topic of growing interest among ethnobiologists, and is integral to the agricultural practices of many ethnic groups across the globe. The ethnoveterinary pharmacopoeia is often composed of ingredients available in the local environment, and may include plants, animals and minerals, or combinations thereof, for use in treating various ailments in reared animals. The aim of this study was to survey the current day ethnoveterinary practices of ethnic Hungarian (Székely) settlements situated in the Erdovidék commune (Covasna County, Transylvania, Romania) and to compare them with earlier works on this topic in Romania and other European countries.
Methods: Data concerning ethnoveterinary practices were collected through semi-structured interviews and direct observation in 12 villages from 2010 to 2014. The cited plant species were collected, identified, dried and deposited in a herbarium. The use of other materials (e.g. animals, minerals and other substances) were also documented. Data were compared to earlier reports of ethnoveterinary knowledge in Transylvania and other European countries using various databases.
Results: In total, 26 wild and cultivated plants, 2 animals, and 17 other substances were documented to treat 11 ailments of cattle, horses, pigs, and sheep. The majority of applications were for the treatment of mastitis and skin ailments, while only a few data were reported for the treatment of cataracts, post-partum ailments and parasites. The traditional uses of Armoracia rusticana, Rumex spp., powdered sugar and glass were reported in each village. The use of some plant taxa, such as Allium sativum, Aristolochia clematitis, and Euphorbia amygdaloides was similar to earlier reports from other Transylvanian regions.
Conclusions: Although permanent veterinary and medical services are available in some of the villages, elderly people preferred the use of wild and cultivated plants, animals and other materials in ethnoveterinary medicine. Some traditional ethnoveterinary practices are no longer in use, but rather persist only in the memories of the eldest subset of the population. A decline in the vertical transmission of ethnoveterinary knowledge was evident and loss of practice is likely compounded by market availability of ready-made pharmaceuticals.
Through the expression of the accessory gene regulator quorum sensing cascade, Staphylococcus aureus is able to produce an extensive array of enzymes, hemolysins and immunomodulators essential to its ability to spread through the host tissues and cause disease. Many have argued for the discovery and development of quorum sensing inhibitors (QSIs) to augment existing antibiotics as adjuvant therapies. Here, we discuss the state-of-the-art tools that can be used to conduct screens for the identification of such QSIs. Examples include fluorescent reporters, MS-detection of autoinducing peptide production, agar plate methods for detection of hemolysins and lipase, High performance liquid chromatography-detection of hemolysins from supernatants, and cell-toxicity assays for detecting damage (or relief thereof) against human keratinocyte cells. In addition to providing a description of these various approaches, we also discuss their amenability to low-, medium-, and high-throughput screening efforts for the identification of novel QSIs.
Background
Ethnobotanical studies on the use of plants amongst migrant populations are of great relevance to public health. Traditional health strategies, which incorporate plants as medicines, foods, or both – can play an important role in individual well-being. However, at the same time, migrant populations’ traditional knowledge of such practices may be under a state of greater threat of decline due to factors such as limited access to the plant materials and physical isolation from the homeland, which serves as the primary living reservoir for this knowledge.
Methods
In this study, we conducted a medical ethnobotanical survey focusing on a comparison of local medicinal food and health strategies with members of two Asian immigrant populations in metro-Atlanta: Chinese and Taiwanese. Snowball sampling techniques were employed to recruit 83 study participants, 57 of which were included in the final analysis. Semi-structured interview techniques were used to question participants about their beliefs and usage of the yin yang system, usage of Chinese herbs and medicinal foods, preference and usage of Eastern and Western medicines, and gardening for medicinal foods.
Results and conclusion
Comparison of the two groups demonstrated a remarkable difference in health strategies concerning medicinal plant use, including statistically significant differences in beliefs concerning yin and yang, uses of Eastern versus Western medicine, and gardening for medicinal foods. Domestic health strategies in the form of medicinal foods play an important role in local health practices, especially among the Taiwanese participants. The collective desire for the use of both Eastern and Western medicine by both groups highlights the important role that cultural competency training will play in preparing allopathic health practitioners to serve increasingly diverse patient populations in the US.
European folk medicine has a long and vibrant history, enriched with the various documented uses of local and imported plants and plant products that are often unique to specific cultures or environments. In this paper, we consider the medicoethnobotanical field studies conducted in Europe over the past two decades. We contend that these studies represent an important foundation for understanding local small-scale uses of CAM natural products and allow us to assess the potential for expansion of these into the global market. Moreover, we discuss how field studies of this nature can provide useful information to the allopathic medical community as they seek to reconcile existing and emerging CAM therapies with conventional biomedicine. This is of great importance not only for phytopharmacovigilance and managing risk of herb-drug interactions in mainstream patients that use CAM, but also for educating the medical community about ethnomedical systems and practices so that they can better serve growing migrant populations. Across Europe, the general status of this traditional medical knowledge is at risk due to acculturation trends and the urgency to document and conserve this knowledge is evident in the majority of the studies reviewed.
Background: Biofilms contribute to the pathogenesis of many forms of Staphylococcus aureus infection. Treatment of these infections is complicated by intrinsic resistance to conventional antibiotics, thus creating an urgent need for strategies that can be used for the prevention and treatment of biofilm-associated infections.
Methodology/Principal Findings: This study demonstrates that a botanical natural product composition (220D-F2) rich in ellagic acid and its derivatives can limit S. aureus biofilm formation to a degree that can be correlated with increased antibiotic susceptibility. The source of this composition is Rubus ulmifolius Schott. (Rosaceae), a plant used in complementary and alternative medicine in southern Italy for the treatment of skin and soft tissue infections. All S. aureus clonal lineages tested exhibited a reduced capacity to form a biofilm at 220D-F2 concentrations ranging from 50-200 μg/mL, which were well below the concentrations required to limit bacterial growth (530-1040 μg/mL). This limitation was therapeutically relevant in that inclusion of 220D-F2 resulted in enhanced susceptibility to the functionally-distinct antibiotics daptomycin, clindamycin and oxacillin. Testing with kidney and liver cell lines also demonstrated a lack of host cell cytotoxicity at concentrations of 220D-F2 required to achieve these effects.
Conclusions/Significance: These results demonstrate that extract 220D-F2 from the root of Rubus ulmifolius can be used to inhibit S. aureus biofilm formation to a degree that can be correlated with increased antibiotic susceptibility without toxic effects on normal mammalian cells. Hence, 220D-F2 is a strong candidate for development as a botanical drug for use in the prevention and treatment of S. aureus biofilm-associated infections.