Abstract Ilex paraguariensis (Aquifoliaceae), commonly known as “yerba mate” or “erva-mate”, is a shrub or tree native to South America. The leaves of the plant are traditionally used to prepare a caffeine-rich infusion with several medicinal properties, including antirheumatic, antithrombotic, anti-inflammatory, anti-obesity, diuretic, and hypocholesterolemic. Ilex paraguariensis is adulterated with several other species of Ilex, such as I. brevicuspis, I. dumosa, and I. theezans. It is also commonly adulterated with unrelated species, such as Citronella gongonha of Cardiopteridaceae. The latter species, commonly called “false-mate”, is one of the most frequent adulterants due to its similar habit and leaf morphology. Comprehensive studies on authentication and quality control of erva-mate are still scarce. This study provides a detailed comparative anatomy of the leaves and stems of I. paraguariensis and C. gongonha by light and scanning electron microscopy. The main distinguishing characteristics are the epidermal cell wall shape, type of stomata, crystal morphotypes, stem shape, presence or absence of glandular trichomes, and sclerenchymatous sheath. This data can help in the authentication and quality control of erva-mate raw materials.

Abstract Monteverdia ilicifolia (Mart. ex Reissek) Biral (basionym: Maytenus ilicifolia Mart. ex Reissek) (Celastraceae) is popularly known as holy thorn or “espinheira-santa” in Brazil. This herb is traditionally used for gastric and digestive problems. However, similar species are often used as adulterants. Considering the pharmacological interest and the existence of adulterants, this study was devoted to characterizing M. ilicifolia samples by Fourier-transform infrared (FTIR) spectroscopy coupled with principal component analysis (PCA) and photoacoustic spectroscopy (PAS) by using Citronella gongonha (Mart.) R. A. Howard as adulterant sample. Six commercial samples were purchased, and seven collected samples were obtained in the Campos Gerais region. The leaves were then dehydrated and converted to powder. The FTIR spectroscopic assay was carried out and consisted of ten different measurements for each sample with a time interval of seven days between them. The PCA was performed from these spectra. The characterization by FTIR demonstrated the presence of tannins and flavonoids in the studied samples. FTIR spectroscopy coupled with PCA was able to discriminate the commercial and the collected samples of M. ilicifolia using three principal components. The photoacoustic spectroscopy resulted in absorption bands centered at ~280, ~380, ~480, and ~630 nm. These bands presented a higher spectral resolution for the collected samples. The commercial samples showed broadening bands, which allowed the differentiation between these two sets of samples. FTIR spectroscopy coupled with PCA, and photoacoustic spectroscopy are alternative tools for the differentiation of M. ilicifolia samples.

Abstract The plant species identification process is one of the most critical stages of quality control of plant raw material. Microscopy serves as the most accessible means for this purpose. Epidermal appendages, such as trichomes, are important botanical markers of plant drugs, taking into account their presence or absence and micromorphology. Trichomes are useful in detecting adulterants or substitutes and in authenticating plant raw materials. The genus Solidago includes two morphologically similar South American species, S. chilensis Meyen and S. microglossa DC. (syn. S. chilensis var. megapotamica). The two species belong to the “S. chilensis” complex and are commonly called arnica-do-mato or arnica. They are morphologically separated primarily on the basis of the average length of the non-glandular trichomes present in the stems. The objective of this study was to search for microscopic markers for the identification and differentiation of these two species to support species identification and quality control of the vegetable raw material. For this purpose, the usual techniques of light and scanning electron microscopy were used. Five types of trichomes were found in this study: I. Simple non-glandular trichome, II. Uniseriate non-glandular trichome, III. Biseriate non-glandular trichome, IV. Flagelliform glandular trichome, and V. Capitate glandular trichome. S. chilensis has simple non-glandular, flagelliform glandular, and rarely capitate glandular trichomes. Whereas, in addition to its glandular trichomes, S. microglossa has two types of non-glandular trichomes: biseriate and uniseriate. Thus, the two South American species of Solidago can be microscopically identified and differentiated based on the presence and absence of the characteristic trichomes. These differences can serve as pharmacognostic subsidies for quality control of the evaluated species.

Abstract In the quality control of herbal drugs, analysis of microscopy structures is crucial to detect any adulterants or substitutes. Microscopic analysis is considered one of the first pharmacopeial parameters of pharmacognostic identification. Cecropia pachystachya Trécul (Urticaceae), commonly known as “embaúba” or Ambay pumpwood, is a broadleaved tree species native to South America, from Brazil to Argentina. Cecropia pachystachya is used in traditional medicine as a diuretic, antiasthmatic, antidiabetic, anti-inflammatory, and anti-hypertensive. Due to the malpractice of adulterating botanicals with other species having similar morphology and therapeutic uses, an unrelated plant Tetrapanax papyrifer (Hook.) K. Koch (Araliaceae) is commonly used as an adulteration of C. pachystachya. Tetrapanax papyrifer was introduced into Brazil and utilized in folk medicine as an antidiarrheal, antitussive, anti-inflammatory, and expectorant. This work aimed to identify and differentiate between the two species using microscopic features of the leaf epidermis. The presence or absence and the morphotype of trichomes are sufficient to identify and differentiate between these species, in whole or pulverized form.

Abstract Baccharis articulata (Lam.) Pers., popularly known as carqueja, carquejinha or carqueja-doce, is a plant widely used in traditional medicine as a diuretic, digestive and antidiabetic. Due to its similar morphology with other species of the "carqueja group", especially Baccharis pentaptera (Less.) DC., it can be easily confused even by specialists. Thus, this study aimed to characterize micromorphology of the crystals present in B. articulata to show botanical markers that can help differentiate this species from other carquejas. Eleven crystalline morphotypes, including druses, styloids and various shapes of prismatic and sand crystals, were evidenced by scanning electron microscopy. In addition, the elemental chemical composition and the degree of hydration of the crystals were analyzed by EDS and Raman spectroscopy. The results of this study would aid in the authentication of B. articulata and serve as a basis for future studies of other species of Baccharis.

Abstract Eugenol is a phenolic compound with numerous biological activities. It is widely used in dentistry to treat toothache and pulpitis. In particular, eugenol may be used for tooth whitening procedures to minimize dental sensitivity in patients. However, eugenol has some disadvantages such as its volatility, its photosensitivity, and immediate effect, which can be avoided by using pharmaceutical nanotechnology. The aim of the present study was to obtain, characterize, quantify, and evaluate the physicochemical stability of eugenol-loaded Eudragit RS100 nanocapsules. The nanocapsules (NCs) were prepared by interfacial deposition of the preformed polymer method. The NCs were characterized through morphological and spectroscopic studies. The encapsulation efficiency was achieved by quantifying the non-encapsulated eugenol using a previously developed and validated analytical method. The physicochemical stability of NCs was assessed at predetermined time intervals for 90 days after preparation. The nanocapsules were successfully prepared by the chosen method and had a predominantly spherical shape with a smooth surface. The mean size, the polydispersion index, and the zeta potential were in agreement to literature data. Infrared spectra ensured that the nanoencapsulation process did not result in chemical reactions between the drug and the polymer. The formulations showed encapsulation efficiency higher than 90% and remained stable after 60 days of preparation. Thus, eugenol-loaded Eudragit RS100 nanocapsules may be further considered as an alternative formulation for dental sensitivity in order to provide a controlled release, a decreased toxicity, and a better dental sensitivity relief.

Abstract Acmella bellidioides (Asteraceae), commonly known as "arnica-do-campo", is a South American native medicinal plant mainly found in Brazil, Argentina, Uruguay and Paraguay. The indigenous people in these regions use the flowers of this plant to treat diseases of the digestive, musculoskeletal and sensory systems. Many Acmella species are morphologically similar, and there are a few anatomical studies available in the literature that can be used to identify and distinguish them. Several other members of Asteraceae, such as Calea uniflora, Chaptalia nutans, Porophyllum ruderale, Pseudobrickellia brasiliensis and Solidago chilensis, are also called "arnica-do-campo" or "arnica". Applying the same common name to several other species makes it difficult to identify the plant correctly and allows it to be more easily adulterated. The present study characterizes A. bellidioides using microscopy and microchemical techniques to provide pharmacobotanical data to support the authentication of the species. The notable anatomical markers identified in A. bellidioides are hypostomatic leaves, anomocytic stomata, peltate glandular trichomes on the leaf abaxial surface, midrib vascular system with three collateral bundles in an open arch, and the presence of prismatic crystals in the leaves and stems. These characteristics can help species identification and differentiation of A. bellidioides from other Acmella species and Asteraceae species known as arnica-do-campo.

Abstract Hydroxytyrosol (HT) is a natural phenolic compound found in leaves of olive trees. It is a photosensitive solid phytochemical constituent and an irritant substance to skin and mucosa as pure drug. HT is a lipophilic chemical constituent and shows low solubility in water, bitter taste, and instability to oxidizing atmosphere. Considering the limitations for its suitable therapeutic use, the aim of the present study was to obtain, to characterize, to quantify, and to evaluate the stability of HT-loaded poly(ԑ-caprolactone) nanocapsules for its further use in pharmaceutical and nutraceutical products. Nanocapsules were prepared by method of interfacial deposition of the preformed polymer. The formulations were characterized by morphological and spectroscopic methods. The UHPLC-PDA analytical method was developed and validated for quantifying the HT encapsulation. Physicochemical stability assay was performed for 120 days. Nanocapsules were successfully obtained by the proposed method. The morphological evaluation demonstrated the drug absence in the nanocapsule surface. Fourier-transform infrared spectroscopy demonstrated the drug nanoencapsulation. The analytical method was validated and confirmed a high HT encapsulation efficiency over 95%. Considering the physicochemical stability testing, the polydispersity index changed after 30 days for NC-2 (HT at 2 mg/mL) and after 90 days for NC-5 (HT at 5 mg/mL). Zeta potential changed after 60 days for both formulations (NC-2 and NC-5). pH values were modified after 60 days for NC-5 and after 90 days for NC-2. HT-loaded PCL nanocapsules demonstrate adequate physicochemical features and high drug encapsulation. The different formulations revealed stability changes from 30 to 90 days. Additional in vitro and in vivo evaluations may be performed in order to use these nanoformulations for treating several diseases based on oxidative-inflammatory environments.

Abstract Phenolic compounds are frequently found in the specific tissues in the leaves and stems of Baccharis species. However, only a few species of the genus have been studied in recent years, including B. erioclada. This study evaluates the in vitro antioxidant potential of B. erioclada crude extract and its fractions. Phytochemical studies, including quantification of total phenolics and flavonoids have also been carried out. Crude extract presented higher antioxidant capacity since it showed lower values of IC50 or greater reductive capacity compared to the fractions. The total phenolic compounds and flavonoids in the crude extract were quantified as 160.66 mg/g and 47.98 mg/g, respectively. Hispidulin showed 27,2296 g/100 g of dried extract. The present study evidenced that B. erioclada extracts are promising sources of antioxidant compounds.