The Influence of Copper and Zinc on Photosynthesis and Phenolic Levels in Basil (Ocimum basilicum L.), Borage (Borago officinalis L.), Common Nettle (Urtica dioica L.) and Peppermint (Mentha piperita L.).

This work is aimed at relationships which govern zinc and copper uptake by four popular medicinal herbs: basil (Ocimum basilicum L.), borage (Borago officinalis L.), common nettle (Urtica dioica L.) and peppermint (Mentha piperita L.). They are often grown in soils with significant copper or zinc levels. Herbs were cultivated by a pot method in controlled conditions. Manganese, iron, copper and zinc concentrations were determined by High-Resolution Continuum Source Flame Atomic Absorption Spectrometry. The efficiency of photosynthesis was estimated by measuring the chlorophyll content, water use efficiency, net photosynthesis, intercellular CO2, stomatal conductance, and transpiration rate. Phenolic compounds were determined by the Folin-Ciocalteu method. Analysis of variance showed that herbs grown in soil treated with copper exhibited a lower iron content in roots, while manganese behaved in the opposite way. The only exception was borage, where a decrease in the manganese content in roots was observed. Both copper and zinc supplementations increased the total content of phenolics, while the highest increases were observed for common nettle and basil. Peppermint and borage responded less to supplementation. In the majority of samples, zinc and copper did not significantly affect the photosynthesis. Herbal extracts from common nettle and basil had unique antioxidant properties and may be good free radical scavengers.

Pyrrolizidine alkaloids in borage (Borago officinalis): Comprehensive profiling and development of a validated LC-MS/MS method for quantification.

Pyrrolizidine alkaloids (PA) from borage (Borago officinalis) consumed as herb and tea, may pose a food safety risk. Therefore, the European Union (EU) set maximum levels of PA in borage, among other foodstuffs, which are applicable since July 1st, 2022. Here, a comprehensive LC-MS/MS based profiling of PA and their N-oxides (PANO) in B. officinalis leaves is presented. Based on these results a targeted, quantitative LC-MS/MS method for the determination of individual PA/PANO present in borage was developed. Chromatographic separation was achieved for all PA/PANO detected in B. officinalis. An easy and fast extraction procedure was developed using a design of experiments approach (DOE). The most efficient extraction was achieved using 0.2% formic acid in 10% methanol at a temperature of 47.5 °C for 60 min. The final method was validated and showed good overall accuracy (recoveries 85-121%) and precision (RDS ≤11%). The method was applied to B. officinalis leave material, demonstrating its suitability for the intended purpose. In these borage samples, the acetylated forms, which are not regulated by EU, were among the quantitatively most relevant PA.

Phenolic Profile and Comparison of the Antioxidant, Anti-Ageing, Anti-Inflammatory, and Protective Activities of Borago officinalis Extracts on Skin Cells.

In this study, methanol and water-methanol extracts of borage (Borago officinalis) herb dried using various methods were analysed for their phenolic profile and biological activity. Twelve compounds, including flavonoids (astragalin, kaempferol 4-glucoside, rutoside, and vitexin) and phenolic acids (caffeic, chlorogenic, 3,4-dihydroxyphenylacetic, ferulic, p-hydroxybenzoic, protocatechuic, rosmarinic, and syringic), were determined qualitatively and quantitatively in B. officinalis extracts by the HPLC-DAD method. The highest total flavonoid content was confirmed for the methanol extract from the hot-air-dried herb, while the methanol extract from the air-dried herb was most abundant in phenolic acids. The results of in vitro tests on human keratinocytes (HaCaT) and fibroblasts (BJ) showed that the extracts were able to reduce the intracellular level of reactive oxygen species in skin cells. Tests performed to assess inhibition of protein denaturation, lipoxygenase activity, and proteinase activity demonstrated that borage extracts have anti-inflammatory properties. In addition, the methanol extract of the herb dried in a convection oven showed the strongest inhibition of both collagenase and elastase activity, which is indicative of anti-ageing properties. The results show that the borage extracts are a source of valuable bioactive compounds with beneficial properties in the context of skin cell protection.

Evaluation of foliar application of selenium and flowering stages on selected properties of Iranian Borage as a medicinal plant.

Many of the active constituents of drug or medicines were originally derived from medicinal plants. Iranian Borage are still being used in regular basis. Selenium (Se) is an essential mineral nutrient for animal and human growth. The aim of this research was to determine the effect of (2, 4, 8 and 16 mg L-1) of as sodium selenate (Na2SeO4) and as sodium selenite (Na2SeO3) on some important properties of Iranian Borage in factorial based on Randomized Complete Block Design via four steps: 2 true leaves stage, ten leaves, 2 weeks and 1 week before flowering. The traits were evaluated during flowering period. Results showed that the highest shoot fresh and dry weight and shoot length, total alkaloid, essential oil percentage were obtained by 4 mg L-1 sodium selenate at the end of flowering. In addition, 4 mg L-1 sodium selenate concentration significantly improved flower yield (diameter, number, weight). The plants were treated with 8 mg L-1 sodium selenate, the higher total phenols and flavonoids, antioxidant activity, soluble sugars, root and fresh weight was seen at end of flowering. When the plants were sprayed with 4 mg L-1 sodium selenite higher total chlorophyll was observed at full of flowering. 16 mg L-1 sodium selenite released the maximum Se acclimation in the petals. 20 composites were discovered containing ɑ-Pinene (23.61%) with sodium selenate in 4 mg L-1. Generally, selenium sources significantly improved morpho-physiological and phytochemical.

The effect of Borago officinalis on the signaling pathway of the NLRP3 inflammasome complex, TLR4 and some inflammatory cytokines in type II diabetic patients with acute respiratory distress syndrome.

Acute respiratory distress syndrome (ARDS) is a life-threatening condition in which the lungs become severely inflamed, causing the alveoli to constrict or fill with fluid, which prevents the lungs from functioning properly. This disease becomes more dangerous when it occurs in patients with diabetes. Because of the clinical condition of these patients, it is not possible to treat them with usual medicines. One of the best options for treating these people is to use herbs. Borage (Borago officinalis) is a medicinal herb that, in addition to its anti-inflammatory properties, is also able to control blood sugar. Therefore, in the current study, the effect of borage oil was considered on the signaling pathway of the NLRP3 inflammasome complex, TLR4, and serum levels of inflammatory cytokines (IL-1? and IL-18) in type II diabetic patients with ARDS. For this purpose, 25 diabetic type II patients with ARDS were divided into three groups by ARDS Berlin Definition. Then, after providing the demographic and clinical characteristics of the patients, they were treated with 30 mg/day borage oil for seven days. The expression of NLRP3 and TLR4 genes (by Real-time PCR technique) and serum levels of IL-1? and IL-18 (by ELISA test) were evaluated before and after treatment with borage oil through blood samples taken from patients. The results showed that serum levels of inflammatory cytokines (IL-1? and IL-18), NLRP3 gene, and TLR4 gene were significantly decreased in diabetic type II patients with mild ARDS by treating with borage oil. IL-1? serum level and TLR4 were significantly decreased in diabetic type II patients with moderate ARDS. But there was not any significant decrease or increase in IL-1?, IL-18, NLRP3 gene, and TLR4 gene in diabetic type II patients with severe ARDS after 7 days of treatment with borage oil. According to the obtained results, borage oil can act as a double-edged blade. Thus, in the early and middle stages of ARDS, borage oil can be effective in reducing the inflammasome pathway of inflammation and also reduce blood sugar levels in these diabetic patients. But in the severe stage of ARDS, it not only does not help to treat the ARDS; it also increases systolic and diastolic blood pressure in diabetic patients.

Haploid Plant Production in Borage (Borago officinalis L.) by Anther Culture.

Borage (Borago officinalis L.) is a crop with different culinary, pharmaceutical, and industrial properties. Besides, it is one of the best known sources of gamma linolenic acid (GLA). However, the variability in the levels of such active compounds, obtained from wild borage, may result in conflicting clinical trial reports, which may likely decrease the optimal efficiency of the product. On the other hand, this important medicinal plant has a multifactorial self-incompatibility system, which makes self-pollination ineffective and results in a limited production of pure (homozygous) lines for breeding programs. To avoid the limitations of self-incompatibility and also producing uniform lines useful as parents for F1 hybrid production, or as starting materials to develop new varieties with high and homogenous levels of medicinal compounds, androgenic doubled haploid (DH) lines produced by anther culture have the potential to speed up the process of producing homozygous lines for breeding program of this medicinal species. In the present chapter, a protocol for production of haploid plants in borage by in vitro anther culture is described.

Differential microbial assemblages associated with shikonin-producing Borage species in two distinct soil types.

Shikonin and its derivatives are the main components of traditional Chinese medicine, Zicao. The pharmacological potential of shikonin and its derivatives have been extensively studied. Yet, less is known about the microbial assemblages associated with shikonin producing Borage plants. We studied microbial profiles of two Borage species, Echium plantagineum (EP) and Lithospermum erythrorhizon (LE), to identify the dynamics of microbial colonization pattern within three rhizo-compatments and two distinct soil types. Results of α and ß-diversity via PacBio sequencing revealed significantly higher microbial richness and diversity in the natural soil along with a decreasing microbial gradient across rhizosphere to endosphere. Our results displayed genotype and soil type-dependent fine-tuning of microbial profiles. The host plant was found to exert effects on the physical and chemical properties of soil, resulting in reproducibly different micro-biota. Analysis of differentially abundant microbial OTUs displayed Planctomycetes and Bacteroidetes to be specifically enriched in EP and LE rhizosphere while endosphere was mostly prevailed by Cyanobacteria. Network analysis to unfold co-existing microbial species displayed different types of positive and negative interactions within different communities. The data provided here will help to identify microbes associated with different rhizo-compartments of potential host plants. In the future, this might be helpful for manipulating the keystone microbes for ecosystem functioning.

The effect of borage, ginger and fennel extracts on acrylamide formation in French fries in deep and electric air frying.

The aim of this study was to evaluate the effect of three Lebanese wild plant extracts on acrylamide (AA) content in French fries, and to investigate the impact of air frying (AF) and deep frying (DF) techniques against AA formation. HPLC showed higher level of AA in DF (1384.79 ng/g) than in AF (163.1 ng/g). Indeed, the plant extracts of ginger, borage and fennel succeeded to decrease AA (59.67, 67.99, and 73.36% in (AF) and 21.91, 66.29 and 29.15% in (DF) respectively)in both fryers. Accordingly, borage fennel and ginger with their high scavenging activity (86.09%, 89.11% 93.67% respectively) and total phenolic contents (298.61, 117.79 and 97.36 of GAE respectively) can act as healthy beneficial pre-treatment, overall reducing AA in potato fries particularly in AF. This study was the first to reveal the importance of using plant extract in reducing AA in potato fries, a staple Lebanese food.

Active biopolymer films based on furcellaran, whey protein isolate and Borago officinalis extract: characterization and application in smoked pork ham production.

BACKGROUND: The meat industry is determined to find biodegradable packaging with properties similar to plastic. Furcellaran (FUR) and whey protein isolate (WPI) were used as a film matrix in which Borago officinalis extract (BOE) was incorporated as an antioxidant compound. The film's mechanical properties, water behavior, surface color, and antioxidant power were analyzed.Smoked hams were manufactured using two different types of film application: cured meat covered with film, smoked and cooked or hamsafter smoking, cooking and cooling. Smoked, vacuum packed ham was used as a control sample. The products were stored at 4 °C for 21 days and analyzed every 7 days. RESULTS: The elongation at break (EAB) and tensile strength (TS) of FUR/WPI films without the extract were 6.30% and 20.59 MPa, respectively, and after incorporating BOE, the EAB and TS were 24.30% and 15.33 MPa, respectively. The films with BOE were darker and had greater antioxidant capacity. The water content and activity in the products with films decreased along with storage time while the control remained stable. The results of microbiological, oxidation product accumulation, and sensory analysis were comparable in all the products. CONCLUSIONS: The smoking time can be reduced due to the dark color of the hams covered with BOE film. The barrier properties of those films should be increased. Other parameters were comparable to plastic packaging. The films therefore have the potential to be used instead of plastic packaging in the meat industry. © 2020 Society of Chemical Industry.

Extraction of Anthocyanins from Borage (Echium amoenum) Flowers Using Choline Chloride and a Glycerol-Based, Deep Eutectic Solvent: Optimization, Antioxidant Activity, and In Vitro Bioavailability.

Borage flower (Echium amoenum), an annual herb native to the Mediterranean region, is an excellent source of anthocyanins and is widely used in various forms due to its biological activities. In the present study, a choline chloride and glycerol (CHGLY)-based natural deep eutectic solvent (NADES) was applied in order to extract the anthocyanins from borage flowers. The traditional solvents, including water, methanol, and ethanol, were used to evaluate the efficiency of CHGLY. The results showed that CHGLY was highly efficient compared to the traditional solvents, providing the highest amounts of the total anthocyanin content (TAC), total phenolic content (TPC), total flavonoid content (TFC), individual anthocyanins, and antioxidant activity (DPPH radical scavenging (DPPH) and ferric-reducing antioxidant power (FRAP) assays). The most dominant anthocyanin found in studied borage was cyanidin-3-glucoside, followed by cyanin chloride, cyanidin-3-rutinoside, and pelargonidin-3-glucoside. The bioavailability % was 71.86 ± 0.47%, 77.29 ± 0.57%, 80.22 ± 0.65%, and 90.95 ± 1.01% for cyanidin-3-glucoside, cyanidin-3-rutinoside, by pelargonidin-3-glucoside and cyanin chloride, respectively. However, cyanidin-3-glucoside was the anthocyanin compound showing the highest stability (99.11 ± 1.66%) in the gastrointestinal environment. These results suggested that choline chloride and glycerol-based NADES is not only an efficient, eco-friendly solvent for the extraction of anthocyanins but can also be used to increase the bioavailability of anthocyanins.

Incorporation of docetaxel and thymoquinone in borage nanoemulsion potentiates their antineoplastic activity in breast cancer cells.

Combining more than one anticancer agent in a nanocarrier is beneficial in producing a formula with a low dose and limited adverse side effects. The current study aimed to formulate docetaxel (DTX) and thymoquinone (TQ) in borage oil-based nanoemulsion (B-NE) and evaluate its potential in impeding the growth of breast cancer cells. The formulated B-NE and the combination (DTX + TQ) B-NE were prepared by the ultra-sonication method and physically characterized by the dynamic light scattering techniques. The cytotoxicity analyses of (DTX + TQ) B-NE in MCF-7 and MDA-MB-231 cells were evaluated in vitro by using the SRB assay. Cell death mechanisms were investigated in terms of apoptosis and autophagy pathways by flow cytometry. The optimum mean droplet sizes formulated for blank B-NE and the (DTX + TQ) B-NE were 56.04 ± 4.00 nm and 235.00 ± 10.00 nm, respectively. The determined values of the half-maximal inhibitory concentration (IC50) of mixing one-half amounts of DTX and TQ in B-NE were 1.15 ± 0.097 µM and 0.47 ± 0.091 µM in MCF-7 and MDA-MB-231 cells, respectively, which were similar to the IC50 values of the full amount of free DTX in both tested cell lines. The treatment with (DTX + TQ) B-NE resulted in a synergistic effect on both tested cells. (DTX + TQ) B-NE induced apoptosis that was integrated with the stimulation of autophagy. The produced formulation enhances the DTX efficacy against human breast cancer cells by reducing its effective dose, and thus it could have the potential to minimize the associated toxicity.

A combination of borage seed oil and quercetin reduces fat accumulation and improves insulin sensitivity in obese rats.

The metabolic properties of omega-6 fatty acid consumption are being increasingly accepted. We had previously observed that supplementation with a borage seed oil (BSO), as a source of linoleic (18:2n-6; LA) and gamma-linolenic (18:3n-6; GLA) acids, reduces body weight and visceral adiposity and improves insulin sensitivity in a diet-induced obesity model of Wistar rats. Here, it was investigated whether the anti-obesogenic properties of BSO could be maintained in a pre-obese model of rats, and if these effects are enhanced by a combination with low doses of quercetin, together with its potential role in the regulation of the adipocyte biology. The combination of BSO and quercetin during 8 weeks was able to ameliorate glucose intolerance and insulin resistance, and to improve liver steatosis. Although no effects were observed on body weight, animals supplemented with this combination exhibited a lower proportion of visceral adiposity. In addition, in vitro differentiation of epididymal adipose-precursor cells of the BSO-treated animals exhibited a down-regulation of Fasn, Glut4, Pparg and Srebp1 genes, in comparison with the control group. Finally, in vitro evaluation of the components of BSO demonstrated that the anti-adipogenic activity of quercetin was significantly potentiated by the combination with both LA and GLA through the down-regulation of different adipogenesis-key genes in 3T3-L1 cells. All these data suggest that omega-6 fatty acids LA and GLA, and their natural sources such as BSO, could be combined with quercetin to potentiate their effects in the prevention of the excess of adiposity and the insulin resistance.

Borage, camellia, centaurea and pansies: Nutritional, fatty acids, free sugars, vitamin E, carotenoids and organic acids characterization.

The present study aimed to evaluate the nutritional and bioactive potential of four edible flowers (borage, centaurea, camellia, and pansies). Significant differences were observed among the four. Water was the main constituent (>76%, fresh weight - fw). Linoleic and palmitic acids were the major fatty acids found in borage and red and yellow pansies, while in camellia it was the arachidic acid. In white pansies, behenic and arachidic acids were predominant. Concerning vitamin E, α-tocopherol was the major vitamer. Carotenoids values varied between 5.8 and 181.4 mg ß-carotene/100 g dry weight (dw) in centaurea and borage, respectively, being particularly rich in lutein. Malic acid was the major organic acid, except in centaurea, where succinic acid was predominant. Fructose, glucose and sucrose were detected in all flowers. These results can contribute to the knowledge of these edible flowers and consequently increase their popularity among consumers and in the food industry.

Freezing of edible flowers: Effect on microbial and antioxidant quality during storage.

Edible flowers are a new gourmet product; however, they are not always available all years. Thus, it is essential to find out technologies to guarantee this product for a longer time. Flowers of four species (borage [Borago officinalis], heartsease [Viola tricolor], kalanchoe [Kalanchoe blossfeldiana], and dandelion [Taraxacum officinale]) were subjected to freezing (in their natural form and in ice cubes) and analyzed in terms of visual appearance, the content of flavonoids, hydrolysable tannins, phenolics, antioxidant activity (2,2-diphenyl-1-picrylhydrazyl radical scavenging activity and reducing power), and microbial quality after storage for 1 and 3 months. Flowers in ice cubes showed similar appearance to fresh ones during the 3 months of storage, whereas frozen flowers were only equivalent up to 1 month with the exception of kalanchoe. Even though flowers in ice cubes showed good appearance after 3 months of storage, they had the lowest values of bioactive compounds and antioxidant activity. On the contrary, when frozen, the content of bioactive compounds maintained or even increased up to 1 month of storage compared to fresh flowers, except for borage. Furthermore, in both freezing treatments, the microorganisms' counts decreased or maintained when compared to fresh samples, except in dandelion. In general, both treatments may allow keeping the flowers after their flowering times. PRACTICAL APPLICATION: The market of edible flowers is increasing, although they are a very perishable product with short shelf-life. Edible flowers are stored in the cold (frozen or in ice cubes); however, the effect on the bioactive compounds and microbial quality that this treatment may have on borage (Borago officinalis), heartsease (Viola tricolor), kalanchoe (Kalanchoe blossfeldiana), and dandelion (Taraxacum officinale) flowers is unknown. So, the present study was conducted to increase the knowledge about the changes that freezing treatments may have in different edible flowers. The results of the present study underline that each flower has different behavior at frozen and ice cubes storage. However, freezing flowers maintain/increase the contents of bioactive compounds, while ice cubes not. Both treatments are effective in protecting flowers from microorganism growth. So, suggesting that both freezing treatments can be used as a preservative method and may allow keeping the flowers after their flowering times.

A systematic review and quality assessment of case reports of adverse events for borage (Borago officinalis), coltsfoot (Tussilago farfara) and comfrey (Symphytum officinale).

Symphytum officinale (comfrey), Tussilago farfara (coltsfoot) and Borago officinalis (borage) have long histories of therapeutic use, but their safety has been questioned due to the presence of unsaturated pyrrolizidine alkaloids (PAs). The evidence base underlying these concerns relies in part on case reports. This systematic review assesses these case reports for their reliability to inform this debate. METHOD: Study selection was restricted to case reports describing possible pyrrolizidine alkaloid related harm and ingestion of comfrey, coltsfoot or borage. An extensive search of academic databases was conducted. Papers meeting the criteria were critically appraised. RESULTS: The search resulted in 11 appropriate case reports, none of which involved borage. Nine reports were assessed for causality and indicated some degree of association between the material ingested and the adverse event. Lack of unequivocal identification of the species ingested compromised attribution and was a significant source of uncertainty. Three levels of identity confusions were found; misidentification or substitution at the level of the whole herb; omission of appropriate botanical identification and attribution of a specific PA to either comfrey or coltsfoot when it is a constituent found in other plants of established toxicity. CONCLUSION: These cases are an unreliable body of evidence on which to draw conclusions about the safety of the oral consumption of Symphytum officinale and Tussilago farfara. Toxicological studies based on oral ingestion of phytochemically-complex preparations of these herbs may be the most accurate methodology for assessing clinical risk.

A Review on the Phytochemistry, Ethnobotanical Uses and Pharmacology of Borago Species.

ETHNOPHARMACOLOGICAL RELEVANCE: Borago L., (family Boraginaceae) is a small genus of annual or perennial herbs with branched flowers, which is commonly found in the Mediterranean region. Some species known as Gavzabȃn in Asian and some African countries are traditionally used instead of Borago. Aims of the review: The purpose of this study was to provide comprehensive scientific information on phytochemistry, traditional uses and pharmacological activities of Borago species to provide an insight into further research on the therapeutic potential of these plants. In many studies, it has been shown that different parts of Borago species, including leaves, flowers, seeds, roots and aerial parts possess numerous ethnobotanical values. MATERIALS AND METHODS: All ethnobotanical, phytochemical, pharmacological, and clinical data were collected from online journals, magazines and books (all of which were published in English, Arabic, and Persian) from 1968 to 2018. Electronic databases such as Google, Google Scholar, PubMed, Science Direct, Researchgate, and other online collections were used. RESULTS: The phytochemical studies on five species showed a wide range of phytochemicals belonging to different classes of secondary metabolites. From a pharmacological point of view, different extracts and fractions, essential oils, and pure compounds isolated from various Borago species have shown diverse activities in in vitro, in vivo, and clinical studies confirming various traditional uses of Borago genus. CONCLUSION: Considering the reported activities of the Borago genus both in traditional and modern medicine, further studies on biological aspects and identification of the mechanism of action for drug discovery are highly required.

Synergistic action of Erigeron annuus L. Pers and Borago officinalis L. enhances anti-obesity activity in a mouse model of diet-induced obesity.

Prior studies show that Borago officinalis L. (BO) can suppress lipid accumulation in 3 T3-L1 adipocytes. Similarly, we recently revealed that Erigeron annuus L. Pers (EA) can significantly diminish both lipid accumulation and adipocyte differentiation in 3 T3-L1 cells through an AMPK (AMP-activated protein kinase)-dependent mechanism. Accordingly, the objective of this present study was to evaluate the anti-obesity activity of EA and/or BO using an animal model of obesity. Obesity was induced in C57BL/6 J mice by feeding a high-fat diet (HFD; 60 kcal% fat) for 3 weeks, followed by administration of EA and/or BO (100-200 mg/kg body weight) or positive control Garcinia Cambogia (GC) (100 mg/kg body weight) for an additional 8 weeks. The anti-obesity effect of EA and/or BO was assessed by measuring body weight, adipocyte size, lipid accumulation, and expression level of genes associated with adipogenesis. We found the administration of EA and/or BO significantly attenuated increases in body weight gain, adipocyte size, and lipid accumulation in obese mice induced by HFD. In addition, western blot analysis revealed that HFD-mediated increases in expressions levels of adipogenic genes such as PPARγ, C/EBPα, and SREBP-1c were diminished by EA and/or BO. Moreover, EA and/or BO significantly stimulated the production of adiponectin, a unique adipokine known to stimulate the breakdown of fat/lipids, whereas adiponectin levels were reduced in mice fed a HFD. Notably, a combination of EA and BO was more effective at modulating such parameters than EA or BO alone. Taken together, these results demonstrate that an anti-obesity effect of EA and/or BO can reduce adipocyte hypertrophy and modulate the expression of adipogenesis-associated genes.

Phytochemical characterization of Borago officinalis L. and Centaurea cyanus L. during flower development.

The present work details the nutritional and chemical compositions of borage and centaurea, at three flowering stages. Water was the main constituent, followed by total dietary fiber. Both flowers showed statistically different (p < 0.05) nutritional and chemical profiles, although in both, polyunsaturated fatty acids (PUFAs) (mainly linoleic and α-linolenic acids), free sugars (3.9-28.9% dw as fructose, glucose, and sucrose), tocopherols (with the major contribution of α-tocopherol from 1.24 to 2.75 mg/100 g dw), carotenoids (0.2-181.4 mg/100 g dw, mainly as lutein), and organic acids (6.1-14.4 g/100 g dw, mainly malic, succinic, and citric acids) were quantified. Concerning flowering, significant differences (p < 0.05) were found for some components, particularly carotenoids; however, no specific trend was observed in either of the two flower species. Thus, the present study shows that each flower species, as well as their flowering stages, may have different phytochemical and nutritional compositions.

Hypoglycemic Activity of Tilia americana, Borago officinalis, Chenopodium nuttalliae, and Piper sanctum on Wistar Rats.

Diabetes mellitus (DM) is considered the epidemic of the 21st century. Traditional medicine uses plants to treat DM; many of these have hypoglycemic effects in both animal models and diabetic patients. Our objective was to evaluate the hypoglycemic activity of Tilia americana, Borago officinalis, Chenopodium nuttalliae, and Piper sanctum on diabetic rats. The methanolic extracts of the plants under study were obtained by Soxhlet extraction. Toxicity was evaluated on Artemia salina; the antioxidant potential was evaluated using the DPPH technique. Hypoglycemic capacity at doses of 250 and 500 mg/kg was tested on Wistar rats with diabetes induced by alloxan (120 mg/kg). The toxicity on A. salina was null for the extracts of B. officinalis and P. sanctum, moderate for T. americana, and highly toxic for C. nuttalliae. The relevant extract of T. americana var. mexicana showed antioxidant activity. Three plants of the studied plants showed hypoglycemic activity: Tilia Americana (p = 0.0142), Borago officinalis (p = 0.0112), and Piper sanctum (p = 0.0078); P. sanctum was the one that showed the greatest reduction in glucose levels at a lower dose.