Pharmacognostic characterization of Dicleptera chinensis by scanning electron microscopy, light microscopy, and analytical techniques.

Dicleptera chinensis J. (Acanthaceae) has been employed in traditional medicinal systems for treating various ailments. It has been used as an anti-inflammatory, wound healing, diuretic, and detoxifying agent in different regions of the world. This study determines several pharmacognostic standards, which are useful to ensure safety, efficacy, and purity of D. chinensis. Different parts of the plant were examined through a scanning electron microscope and light microscope, and cross-section images revealed several useful botanical features of the plant. The color, size, odor, shape, and surface characteristics of plant parts were also examined macroscopically. Pharmacognostic standardization parameters including ash values, loss on drying, swelling index, hemolytic index, and foaming index were determined in accordance with WHO guidelines. Heavy metal analysis was executed through atomic absorption spectrophotometer which depicted the presence of heavy metals and trace elements within the acceptable range. Qualitative phytochemical tests for alkaloids, flavonoids, saponins, glycosides, tannins, carbohydrates, lipids, protein, and so forth of plant extract were also performed, which showed the valuable amount of these phytochemicals useful for medicinal purposes. Preliminary phytochemical tests provide an indication for major phytoconstituents classes present in the plant. These quantitative and qualitative microscopic features are helpful in establishing the pharmacopeia standards of plant. Assessment of various pharmacognostic features such as morphology of various plant parts explained along with physicochemical and phytochemical analysis could be very helpful for future research. RESEARCH HIGHLIGHTS: Pharmacognostic standardization is employed as reported evidence for correct identification of D. chinensis. Structures identified by scanning electron microscopy and light microscopy serve as diagnostic features of plant. Important secondary metabolites present in the plant suggest the need for further exploration through advanced metabolomics and other analytical techniques.

Pharmacognostic standardization of Rhododendron afghanicum through scanning electron microscopy and analytical techniques.

The aim of this study was to assess and compare the pharmacognostic and microscopic features of the selected parts of Rhododendron afghanicum Aitch. & Hemsl. It is a perennial and shrub. Anatomy of stem and leaves depicted dicot structure. It will provide knowledge about standardization, authentication, and adulteration with its co-species. The macroscopic examination reveals that fresh leaves are green, pleasant odor with a bitter taste. The leaf is oblong-elliptic in shape and sub-acute at apex; rounded at the base with entire margin. Stem is irregular and the outer surface is light brown, rough with fissures and ridges. Microscopic examination indicated the presence of xylem, phloem, peltate trichome, epidermal cells, collenchymas cells, paracytic stomata, and reticulate vessels. Stem microscopy reveals epidermis, hypodermis, cortex, sclerenchymatous sheath, phloem, xylem, and pith. It will be helpful in identification and quality control. Micro-morphological features were observed through SEM. EDX spectroscopy were carried out and revealed the presence of calcium, silicon, and potassium. Phytochemical analysis revealed the presence of tannins, saponins, phenols, protein, flavonoids, glycosides, and alkaloids. Ethyl acetate for leaf and stem demonstrate the highest extractive values (18% and 13%), respectively. XRD peaks appeared at 30.21, 28.73, 205.73, 200.73, 380.07, 390.24, 490.11, and 450.33ο . This will be helpful to identify the ownership of herbal drugs by the diffraction peaks through crystal structures and atomic spacing. These parameters are crucial for drug identification, standardization, authentication, and drug designing. These studies also provided knowledge regarding therapeutic and nutraceutical importance of this plant. RESEARCH HIGHLIGHTS: The current pharmacognostic studies carried out on Rhododendron afghanicum can serve as a basis for compiling keys for finding the taxonomic identification and authentication of the said species by morphological, anatomical, and physicochemical features.

Microscopic investigations and pharmacognostic techniques used for the standardization of leaf of Rhus succedanea var. Himalaica J. D. Hook.

Rhus succedanea is generally traded, distributed, and sold in the markets in its crude and raw form. This may have been mixed with adulterants, mismanaged by malpractices, and substituted with other closely related drugs having different effect. This study is therefore carried out to authenticate the plant through pharmacognostic evaluations including morphological microscopic and physio-chemical features. Morphologically, the Rhus is a perennial small sized deciduous tree, locally, called as Rakhkal in Pashto and Kakarsingi in Urdu. The organoleptic evaluation showed that leaf had pleasant, aromatic odor, and astringent taste. Anatomy of the midrib has shown a typical dicot histological differentiation. The leaf was hypostomatic showing anomocytic stomata with average stomatal number 27.1 ± 7.2 and stomatal index 14 ± 3.63. The average vein islet, vein termination, and palisade ratios were 13.6 ± 3.04, 10.21 ± 1.92, and 6 ± 2.01, respectively. Leaf powder showed the existence of various types of tissues. Fluorescence study and percentage extractive values were also carried out. The phytochemical screening showed the presence of carbohydrates, protein, alkaloids, phenols, flavonoids, terpenoids, and anthraquinones, whereas tannins and fixed oil was not detected. Quantitatively highest number of alkaloids 16% and flavonoids 19% in leaf was detected. The above parameters, being reported to the first time for, and are significant toward establishing the microscopic and pharmacognostic standards for future identification and authentication of genuine herbal drug.

Ethnophytotechnology: Harnessing the Power of Ethnobotany with Biotechnology.

Ethnobotany (the scientific study of traditional plant knowledge) has aided the discovery of important medicines. However, as single-molecule drugs or synergistic mixtures, these remedies have faced obstacles in production and analysis. Now, advances in bioreactor technology, metabolic engineering, and analytical instrumentation are improving the production, manipulation, and scientific understanding of such remedies.

Cannabis cultivation: Methodological issues for obtaining medical-grade product.

As studies continue to reveal favorable findings for the use of cannabidiol in the management of childhood epilepsy syndromes and other disorders, best practices for the large-scale production of Cannabis are needed for timely product development and research purposes. The processes of two institutions with extensive experience in producing large-scale cannabidiol chemotype Cannabis crops-GW Pharmaceuticals and the University of Mississippi-are described, including breeding, indoor and outdoor growing, harvesting, and extraction methods. Such practices have yielded desirable outcomes in Cannabis breeding and production: GW Pharmaceuticals has a collection of chemotypes dominant in any one of eight cannabinoids, two of which-cannabidiol and cannabidivarin-are supporting epilepsy clinical trial research, whereas in addition to a germplasm bank of high-THC, high-CBD, and intermediate type cannabis varieties, the team at University of Mississippi has established an in vitro propagation protocol for cannabis with no detectable variations in morphologic, physiologic, biochemical, and genetic profiles as compared to the mother plants. Improvements in phytocannabinoid yields and growing efficiency are expected as research continues at these institutions. This article is part of a Special Issue entitled "Cannabinoids and Epilepsy".

Reverse Pharmacognosy and Reverse Pharmacology; Two Closely Related Approaches for Drug Discovery Development.

Pharmacognosy is a science, which study natural products as a source of new drug leads and effective drug development. Rational and economic search for novel lead structures could maximize the speed of drug discovery by using powerful high technology methods. Reverse pharmacognosy, a complementary to pharmacognosy, couples the high throughput screening (HTS), virtual screening and databases along with the knowledge of traditional medicines. These strategies lead to identification of numerous in vitro active and selective hits enhancing the speed of drug discovery from natural sources. Besides, reverse pharmacology is a target base drug discovery approach; in the first step, a hypothesis is made that the alteration of specific protein activity will produce beneficial curative effects. Both, reverse pharmacognosy and reverse pharmacology take advantages of high technology methods to accomplish their particular purposes. Moreover, reverse pharmacognosy effectively utilize traditional medicines and natural products as promising sources to provide new drug leads as well as promote the rational use of them by using valuable information like protein structure databases and chemical libraries which prepare pharmacological profile of traditional medicine, plant extract or natural compounds.

[Education Program of Kampo-medicine for Undergraduates in Preparation for Clinical Setting].

Kampo-medicine has become popular in Japanese medical practice combined with western medicine. For example, Daikenchu-To for intestinal obstruction after surgical operation, Shakuyakukanzo-To and Goshajinki-Gan for anti-cancer agents-induced neuropathy, and Yokkan-San for behavioral psychological symptoms of dementia are alternatively used in addition to conventional treatments in Japan. However, combined use of Kampo-medicine and western medicine may cause unexpected adverse events including undesirable drug-drug interactions because Kampo-medicine was not originally developed to be used with western medicine. Although adverse effects of Kampo-medicine are rare compared with those of western medicine, severe events such as liver dysfunction and interstitial pneumonia have been reported in increasing trends. Medical staff including pharmacists, therefore, should be aware of the onset of adverse events before the patients' symptoms become severe. Several adverse effects are caused by chemical constituents such as glycyrrhizin in licorice for pseudoaldosteronism and geniposide in Gardeniae fructus for mesenteric phlebosclerosis. To understand the adverse effects of Kampo-medicine, pharmacists should learn trends in current medication as well as pharmacology and toxicology of the chemical constituents in pharmacognosy. These issues should also be addressed in educational materials for students of clinical pharmacy and pharmacy practice.

Pharmacognostical Studies.

The chapter deals with tools and techniques employed in pharmacognosy. Pharmacognostic evaluation helps to screen the commercial varieties, substitutes, adulterants and any other quality control of the drugs. It is a simple and reliable tool, helps to obtain information about biochemical and physical properties of crude drug. Methods such as macroscopic and microscopic analysis, maceration, histochemical colour reaction, photomicrography, organoleptic character of plant powder and extracts, fluorescence analysis of plant powder with different chemical reagents, determination of pH of plant powder, water solubility index (WSI) and water absorption index (WAI) and acid value are discussed.

PHARMACOGNOSTIC EVALUATION OF THE LEAF OF Rhus succedanea VAR. HIMALAICA. J. D HOOKER.

BACKGROUND: Rhus succedanea is generally traded, distributed and sold in the markets in its crude and raw form. This may have been mixed with adulterants, mismanaged by malpractices and substituted with other closely related drugs having different effect. This study is therefore carried out to authenticate the plant through pharmacogonostic evaluations. MATERIAL & METHODS: The organoleptic studies were carried through sensory organs i.e size, shape, texrure, odour, etc. Histological studies were conducted by preparing hand slides, mounting the specimen in potato tuber; fluorescence characters were determined through UV and phytochemical screening was investigated using various standard and common methods from relevant literature. RESULTS: Morphologically, the Rhus is a perennial small sized deciduous tree, 5-9 m tall with opposite imparipinnately compound leaves and small grayish yellow flowers born on paniculate inflorescence; locally, called as Rakhkal in Pashto and Kakarsingi in Urdu. The organoleptic evaluation showed leaf had pleasant, aromatic odour and astringent taste. Transverse section of leaf through midrib region was worked out. The anatomy of the midrib has shown to be surrounded by both upper and lower epidermis with multicellular non-glandular trichomes. The leaf was hypostomatic showing anomocytic stomata with average stomatal number 27.1 ± 7.2 and stomatal index 14 ± 3.63. The average vein islet, vein termination and palisade ratios were 13.6 ± 3.04, 10.21 ± 1.92 and 6 ± 2.01 respectively. Leaf powder showed the existance of anomocytic stomata, spirally thickened xylem vessels, non-glandular multicellular and stellate trichomes. Fluorescence study and percent extractive values was also carried out. The phytochemical screening showed the presence of carbohydrates, protein, alkaloids, phenols, flavonoids, terpenoids and anthraquenones, while tannins and fixed oil was not detected. Quantitatively highest amount of alkaloids 16% and flavonoids 19% in leaf was detected. CONCLUSION: The results of the of the anatomical, organoleptic and physiochemical studies of the powder of leaf will be helpful in standardization of R. succedanea the crude drug.

Utilização de planejamento fatorial para a determinação da capacidade antioxidante e doseamento de flavonoides totais em Verbena minutiflora Briq. ex Moldenke (gervai) / The use of factorial design for determining the antioxidant capacity and dosing the total flavonoids in Verbena minutiflora Briq. Ex Moldenke (Gervai)

RESUMO Verbena minutiflora Briq. ex Moldenke (gervai) tem seu uso medicinal relatado popularmente para tratamento de doenças hepáticas, diarreia e outros problemas de saúde. Entretanto, pouco se conhece a respeito de seus componentes químicos e estudos que comprovem suas propriedades medicinais são escassos. O objetivo desse estudo foi avaliar a composição química dos extratos aquosos e etanólicos de flores de V. minutiflora e otimizar processos de obtenção de extratos com maiores capacidades antioxidantes e maiores concentrações de flavonoides. O método de extração foi desenhado por planejamento fatorial, onde as variáveis para a determinação da capacidade antioxidante foram: pH, extração líquida, método e tempo de extração. Para a determinação de flavonoides totais as variáveis avaliadas por planejamento fatorial foram: concentração de hexametilenotetramina, tipo de ácido, volume de ácido e tempo de aquecimento. Os resultados das análises químicas dos extratos mostraram: aminogrupos, taninos e ácidos fixos (extrato aquoso) aminogrupos, flavonoides, triterpenos, esteroides, alcaloides e cumarinas (extrado hidroetanólico). Os resultados dos planejamentos fatoriais mostraram que o melhor método de extração para a capacidade antioxidante foi o que usou vórtex, por 35 min, com água:etanol 50:50, com pH1, obtendo 0,1899± 5,8.10-3 mmol expressos em ácido ascórbico g-1 nos extratos de V. minutiflora. Enquanto, para as dosagens de flavonoides totais as variáveis significantes foram: tipo de ácido e volume de ácido. A melhor extração obtida foi: 6,748. 10-2± 2,085 10-3% expressos em quercetina. Os resultados mostraram que o planejamento fatorial é uma importante ferramenta para a otimização de extração de componentes químicos em produtos naturais.

ABSTRACT Verbena minutiflora Briq. ex Moldenke (gervai) has its popular use reported for liver disorders treatments, diarrhea, and other health problems. However, little is known about its chemical components and studies that proves its medicinal properties are rare. The aim of this study was to evaluate the chemical composition of aqueous and ethanolic extracts from flowers of V. minutiflora and to optimize processes to obtain extracts with higher antioxidant capacity and greater concentration of flavonoids. The methods of extraction were designed by factorial planning, where the variables to determine the antioxidant capacity were: pH; extraction liquid; method and extraction time. To determinate the total flavonoids the variables evaluated by factorial design were: concentration of hexamethylenetetramine; type of acid; volume of acid and warming time. The results of chemical analysis of the extracts showed: amino groups, tannins and fixed acids (aqueous extract) amino groups, flavonoids, triterpenes, steroids, alkaloids and coumarins (hydroalcoholic extract). The factorial designs results showed that the best extraction method for the antioxidant capacity was the one that uses vortex, for 35 min, with water: ethanol 50:50, at pH 1, getting 0,1899 ± 5,8.10-3 mmol expressed in ascorbic acid g-1 in extracts of V. minutiflora . While, for dosages of total flavonoids the significant variables were the type of acid and volume of acid. The best extraction obtained was: 6,748. 10-2± 2,085 10-3% expressed in quercetin. These data showed that the factorial design is an important tool in optimizing the extraction of chemical components in natural products.

[Pharmacognosy study of Verbascum species]. / A Verbascum sp. farmakognóziai vizsgálata.

The mullein (Verbascum phlomoides L., V thapsus L., V. thapsiforme Schrad., V. speciosum L.) is a medicinal herb known and used for a long time, especially in traditional Turkish medicine. The aims of our study were to identify the species and study the plant's major active substances both qualitatively and quantitatively, comparing it to data found in scientific literature. The plants were identified as probable hybrids of V. phlomoides and V. thapsiforme. Microscopic analysis of the flowers showed no major difference between the specimens. The diameter of both stomata and pollen we observed was around 15-20 µm. Important flavonoids like rutin and quercetin were identified. Dosage resulted in a 0.135% total flavonoid aglycone content. (expressed as hypericin) and a 1.3% total flavonoid glycoside content (expressed as rutoside). Thin layer chromatography from saponines revealed two spots. A hemolytic index of 13095 was also determined. Repeating the dosage experiment a year later resulted in significantly lower flavonoid aglycone and glycoside content (0.006% and 0.95% respectively) as well as a hemolytic index of approximately 4000.

The relevance of pharmacognosy in pharmacological research on herbal medicinal products.

As all medicines, herbal medicinal products are expected to be safe, effective, and of appropriate quality. However, regulations on herbal medicinal products vary from country to country, and herbal preparations do occur not only in the form of medicinal products but also as less strictly regulated product groups like dietary supplements. Therefore, it is not always easy for the consumers to discriminate high-quality products from low-quality products. On the other hand, herbal medicines have many special features that distinguish them from conventional medicinal products. Plants are complex multicomponent mixtures; in addition, their phytochemical composition is not constant because of inherent variability and a plethora of external influences. Therefore, the production process of an herbal medicinal product needs to be strictly monitored. First of all, the starting materials need to be correctly authenticated and free of adulterants and contaminants. During plant growth, many factors like harvest season and time, developmental stage, temperature, and humidity have a strong impact on plant metabolite production. Also, postharvest processing steps like drying and storage can significantly alter the phytochemical composition of herbal material. As the production of many phytopharmaceuticals includes an extraction step, the extraction solvent and conditions need to be optimized in order to enrich the bioactive constituents in the extract. The quality of finished preparations needs to be determined either on the basis of marker constituents or on the basis of analytical fingerprints. Thus, all production stages should be accompanied by appropriate quality assessment measures. Depending on the particular task, different methods need to be applied, ranging from macroscopic, microscopic, and DNA-based authentication methods to spectroscopic methods like vibrational spectroscopy and chromatographic and hyphenated methods like HPLC, GC-MS and LC-MS. Also, when performing pharmacological and toxicological studies, many features inherent in herbal medicinal products need to be considered in order to guarantee valid results: concerning in vitro studies, difficulties are often related to lacking knowledge of ADME characteristics of the bioactive constituents, nuisance compounds producing false positive and false negative results, and solubility problems. In in vivo animal studies, the route of administration is a very important issue. Clinical trials on herbal medicinal products in humans very often suffer from a poor reporting quality. This often hampers or precludes the pooling of clinical data for systematic reviews. In order to overcome this problem, appropriate documentation standards for clinical trials on herbal medicinal products have been defined in an extension of the CONSORT checklist. This article is part of a Special Issue entitled "Botanicals for Epilepsy".

Pharmacognostic standardization and preliminary phytochemical studies of Gaultheria trichophylla.

CONTEXT: Gaultheria trichophylla Royle (Ericaceae) has long been used for various ailments in traditional systems of medicines; most importantly it is used against pain and inflammation. AIMS: This study determines various pharmacognostic and phytochemical standards helpful to ensure the purity, safety, and efficacy of medicinal plant G. trichophylla. MATERIAL AND METHODS: Intact aerial parts, powdered materials, and extracts were examined macro- and microscopically and pharmacognostic standardization parameters were determined in accordance with the guidelines given by the World Health Organization (WHO). Parameters including extractive values, ash values, and loss on drying were determined. Preliminary phytochemical tests, fluorescence analysis, and chromatographic profiling were performed for the identification and standardization of G. trichophylla. RESULTS: The shape, size, color, odor, and surface characteristics were noted for intact drug and powdered drug material of G. trichophylla. Light and scanning electron microscope images of cross section of leaf and powdered microscopy revealed useful diagnostic features. Histochemical, phytochemical, physicochemical, and fluorescence analysis proved useful tools to differentiate the powdered drug material. High-performance liquid chromatography (HPLC) analysis showed the presence of important phytoconstituents such as gallic acid, rutin, and quercetin. DISCUSSION AND CONCLUSIONS: The data generated from the present study help to authenticate the medicinally important plant G. trichophylla. Qualitative and quantitative microscopic features may be helpful for establishing the pharmacopeia standards. Morphology as well as various pharmacognostic aspects of different parts of the plant were studied and described along with phytochemical and physicochemical parameters, which could be helpful in further isolation and purification of medicinally important compounds.

Authentication of Polygonati Odorati Rhizoma and other two Chinese Materia Medica of the Liliaceae family by pharmacognosy technique with GC-MS analysis.

Yuzhu (Polygonati Odorati Rhizoma), Kangdingyuzhu (Polygonati Prattii Rhizoma), and zhugenqiyuzhu (Disporopsis Fuscopictae Rhizoma) are of the same family, but of different genera. They have all often used in Chinese Materia Medica (CMM) as Polygonati Odorati Rhizoma in China market. Three species of CMM are confused. For better application, we need to identify these plants accurately. This study use pharmacognosy technique and GC-MS analysis, three species of CMM were authenticated. In macroscopic characteristics, the fruit of Polygonati Odorati Rhizoma is blue-black, while the other two are maroon and dark purple orderly. Nodes of Polygonati Odorati Rhizoma are upward and light uplift, about 1 cm spacing, while the other are not. As for microscopic characteristics, the cortex of Polygonati Odorati Rhizoma only occupies about 1/5 of the radius of the transverse section with inconspicuous endodermis, which is much smaller than others. The type of vascular bundles of Polygonati Odorati Rhizoma is closed collateral, but the other is amphivasal. Raphides of calcium oxalate are scattered, but Raphides of the other two are like brooms and neat rows. GC-MS analysis of essential oil could provide different characteristics to distinguish three species. Twenty-three compounds were identified from essential oil of Polygonati Odorati Rhizoma and the main components were n-hexadecanoic acid (49.45%), while n-hexadecanoic acid of the other two are 23.92% and 9.45%. The content of n-hexadecanoic is strongly different. This research was aimed to establish a method by pharmacognosy and GC-MS analysis to identify three CMM and for providing scientifical data to ensure accuracy of origin of three species.

[Analysis and outlook on teaching status of Molecular Pharmacognosy].

The teaching status of Molecular Pharmacognosy in 28 institutions in China was investigated by questionnaire and the survey data was analyzed by SPSS. Research contents included course beginning years, majors, class hours, characteristics of the course, teaching ways, the theory and practice contents, evaluation modes, selection of teaching material, teaching achievements, teachers and so on for undergraduates and graduates. Research results showed that with 20 years' development, Molecular Pharmacognosy had been offered for both undergraduate and graduate students in at least 20 colleges and universities and Molecular Pharmacognosy education in China showed good development momentum. At the same time, to promote the development of Molecular Pharmacognosy further, investment for it should be increased and practical teaching condition should be improved.

Stability of Tilo ® tablets formulation obtained from dry extract of Justice pectoralis Jacq

Justicia pectoralis Jacq., Acanthaceae, is a herb known popularly in Cuba as Tilo and used traditionally as sedative. The development in a solid pharmaceutical (Tablets 100 mg) using dry extract of Justicia pectolaris aqueous extract is of interest for the development of phytomedicines, which uses this active raw material. The aim of the present study was to carry out chemical and biological stability studies to the formulation. A method of coumarin determination by High Performance Liquid Chromatography (HPLC) was used and validated. The stability studies during different periods of time (24 months) showed a stability of the product stored at 32 ± 2 °C, and protected of the light.

Justicia pectoralis Jacq., Acanthaceae é uma erva conhecida popularmente em Cuba como Tilo e utilizada tradicionalmente como sedativo. O desenvolvimento de formas farmacêuticas sólidas (comprimido 100 mg) usando extrato aquoso seco de J. pectoralis é de interesse no desenvolvimento de fitoterápicos que empreguem esse princípio ativo. O objetivo do presente estudo foi realizar estudos de estabilidade químicos e biológicos da formulação. Um método de determinação de cumarinas por Cromatografia Líquida de Alta Eficiência (CLAE) foi usado e devidamente validado. Os estudos de estabilidade durante diferentes períodos de tempo (24 meses) mostraram a estabilidade do produto preservado a 32 ± 2 °C e protegido da luz.

Modern extraction techniques and their impact on the pharmacological profile of Serenoa repens extracts for the treatment of lower urinary tract symptoms.

BACKGROUND: Bioactive compounds from plants (i.e., Serenoa repens) are often used in medicine in the treatment of several pathologies, among which benign prostatic hyperplasia (BPH) associated to lower urinary tract symptoms (LUTS). DISCUSSION: There are different techniques of extraction, also used in combination, with the aim of enhancing the amount of the target molecules, gaining time and reducing waste of solvents. However, the qualitative and quantitative composition of the bioactives depends on the extractive process, and so the brands of the recovered products from the same plant are different in terms of clinical efficacy (no product interchangeability among different commercial brands). SUMMARY: In this review, we report on several and recent extraction techniques and their impact on the composition/biological activity of S. repens-based available products.

Supplements for exotic pets.

The use of supplements has become commonplace in an effort to complement traditional therapy and as part of long-term preventive health plans. This article discusses historical and present uses of antioxidants, vitamins, and herbs. By complementing traditional medicine with holistic and alternative nutrition and supplements, the overall health and wellness of exotic pets can be enhanced and balanced. Further research is needed for understanding the strengths and uses of supplements in exotic species. Going back to the animals' origin and roots bring clinicians closer to nature and its healing powers.