Larrea divaricata a native Argentine plant with potential activity against SARS-CoV-2? / ¿Larrea divaricata una planta nativa argentina con actividad potencial sobre SARS-CoV-2?

Larrea divaricata Cav. is an autochthonous South American plant popularly used in inflammatory and infectious diseases with reported anti - inflammatory, immunomodulatory, antimicrobial and antioxidant activities. Covid - 19 is an infection ca used by the severe acute respiratory syndrome coronavirus 2 (SARS - CoV - 2). This virus can cause pneumonia and even death in about 5% of the cases. The objective of the article was to demonstrate, through a literature review, that L. divaricata has sufficie nt attributes to be assayed against SARS - CoV - 2. For this, the chemical composition, reported activities and docking studies were taken into account. This review demonstrated that the plant extracts are capable of inhibiting the proliferation of fungi, bact eria and viruses and that they exert anti - inflammatory and immunomodulatory actions in different " in vitro " and " in vivo " models. These results suggest that the plant is a good candidate to be studied for the prevention and/or treatment of SARS - CoV - 2.

Larrea divaricata Cav. es una planta autóctona Sudamericana, utilizada popularmente en enfermedades inflamatorias e infecciosas, con activida d anti - inflamatoria, inmunomoduladora, antimicrobiana y antioxidante reportada. El Covid - 19 es una infección causada por una cepa de coronavirus, SARS - CoV - 2 (coronavirus tipo 2 causante del síndrome respiratorio agudo severo). Este virus puede originar neu monía e incluso la muerte en alrededor del 5% de los casos. Nuestro objetivo fue demostrar, a través de una revisión bibliográfica, que esta planta tiene atributos suficientes para ser ensayada en estudios contra SARS - CoV - 2. Se tuvo en cuenta la composici ón química, los antecedentes científicos y los estudios de acoplamiento molecular. Esta revisión permitió demostrar que extractos de la planta son capaces de inhibir la proliferación de hongos, bacterias y virus y que presentan acción anti - inflamatoria en diferentes modelos " in vitro " e " in vivo ", lo que los hace candidatos a ser estudiados en la prevención y/o tratamiento de la infección contra SARS - CoV - 2.

In Vitro Antiviral Activity of Nordihydroguaiaretic Acid against SARS-CoV-2.

The coronavirus infectious disease 2019 (COVID-19) is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and has been spreading rapidly worldwide, creating a pandemic. This article describes the evaluation of the antiviral activity of nordihydroguaiaretic acid (NDGA), a molecule found in Creosote bush (Larrea tridentata) leaves, against SARS-CoV-2 in vitro. A 35 µM concentration of NDGA was not toxic to Vero cells and exhibited a remarkable inhibitory effect on the SARS-CoV-2 cytopathic effect, viral plaque formation, RNA replication, and expression of the SARS-CoV-2 spike glycoprotein. The 50% effective concentration for NDGA was as low as 16.97 µM. Our results show that NDGA could be a promising therapeutic candidate against SARS-CoV-2.

Evolutionary importance of the relationship between cytogeography and climate: New insights on creosote bushes from North and South America.

Relationships between genome size and environmental variables suggest that DNA content might be adaptive and of evolutionary importance in plants. The genus Larrea provides an interesting system to test this hypothesis, since it shows both intra- and interspecific variation in genome size. Larrea has an amphitropical distribution in North and South American deserts, where it is most speciose. Larrea tridentata in North America shows a gradient of increasing autopolyploidy; while three of the four studied South American species are diploids, Larrea divaricata, Larrea nitida, Larrea ameghinoi, and the fourth is an allopolyploid, Larrea cuneifolia. We downloaded available focal species' georeferenced records from seven data reservoirs. We used these records to extract biologically relevant environmental variables from WorldClim at 30 arc seconds scale, to have a broad characterization of the variable climatic conditions of both regions, and a climatic envelope for each species. We estimated relative DNA content index and relative monoploid genome values, by flow cytometry, of four most abundant Larrea species throughout their respective ranges. Then we winnow the bioclimatic dataset down to uncorrelated variables and sampled locales, to analyse the degree of association between both intra- and interspecific relative DNA content and climatic variables that are functionally relevant in arid environments using Pearson correlations, general linear and mixed effects models. Within the genus Larrea, relative DNA content increases with rising temperature and decreases with rising precipitation. At the intraspecific level, all four species show relative DNA content variation across climatic conditions. Larrea is a genus that shows genome size variation correlated with climate. Our results are also consistent with the hypothesis that extreme environmental pressures may have facilitated repeated whole genome duplication events in North America, while in South America, reticulate evolution, as allopolyploidization, and speciation might have been climate-dependent since the Oligocene.

New insights into the antiviral activity of nordihydroguaiaretic acid: Inhibition of dengue virus serotype 1 replication.

BACKGROUND: Dengue virus (DENV) is considered one of the most important pathogens in the world causing 390 million infections each year. Currently, the development of vaccines against DENV presents some shortcomings and there is no antiviral therapy available for its infection. An important challenge is that both treatments and vaccines must be effective against all four DENV serotypes. Nordihydroguaiaretic acid (NDGA), isolated from Larrea divaricata Cav. (Zygophyllaceae) has shown a significant inhibitory effect on a broad spectrum of viruses, including DENV serotypes 2 and 4. PURPOSE: We evaluated the in vitro virucidal and antiviral activity of NDGA on DENV serotype 1 (DENV1), including the study of its mechanism of action, to provide more evidence on its antiviral activity. METHODS: The viability of viral particles was quantified by the plaque-forming unit reduction method. NDGA effects on DENV1 genome and viral proteins were evaluated by qPCR and immunofluorescence, respectively. Lysosomotropic activity was assayed using acridine orange and neutral red dyes. RESULTS: NDGA showed in vitro virucidal and antiviral activity against DENV1. The antiviral effect would be effective within the first 2 h after viral internalization, when the uncoating process takes place. In addition, we determined by qPCR that NDGA decreases the amount of intracellular RNA of DENV1 and, by immunofluorescence, the number of cells infected. These results indicate that the antiviral effect of NDGA would have an intracellular mechanism of action, which is consistent with its ability to be incorporated into host cells. Considering the inhibitory activity of NDGA on the cellular lipid metabolism, we compared the antiviral effect of two inhibitors acting on two different pathways of this type of metabolism: 1) resveratrol that inhibits the sterol regulatory element of binding proteins, and 2) caffeic acid that inhibits the 5-lipoxygenase (5-LOX) enzyme. Only caffeic acid produced an inhibitory effect on DENV1 infection. We studied the lysosomotropic activity of NDGA on host cells and found, for the first time, that this compound inhibited the acidification of cell vesicles which would prevent DENV1 uncoating process. CONCLUSION: The present work contributes to the knowledge of NDGA activity on DENV. We describe its activity on DENV1, a serotype different to those that have been already reported. Moreover, we provide evidence on which stage/s of the viral replication cycle NDGA exerts its effects. We suggest that the mechanism of action of NDGA on DENV1 is related to its lysosomotropic effect, which inhibits the viral uncoating process.

Phytochemical Compounds and Pharmacological Properties of Larrea tridentata.

For centuries, traditional medicine from plants (phytotherapy) was the only treatment for infectious and non-infectious diseases. Although it is still practiced in several countries with excellent therapeutic results, it is frequently underestimated because, unlike Western medicine, it is not based on an empirical scientific foundation. However, interest in the search for plant-based therapeutic resources has been stimulated by disciplines such as phytochemistry and the side effects of conventional pharmacological therapies. For example, Larrea tridentata is a perennial shrub used in traditional medicine in northern Mexico and the southern United States to treat infertility, rheumatism, arthritis, colds, diarrhea, skin problems, pain, inflammation and excess body weight. Scientific research has revealed its beneficial effects-antioxidant, antitumor, neuroprotective, regenerative, antibacterial, antiviral, antifungal, anthelmintic, antiprotozoal and insecticidal-although reports indicate that some compounds in Larrea tridentata may be hepatotoxic and nephrotoxic. Therefore, the aim of this review was to highlight the updates regarding phytochemical compounds and the pharmacological properties of Larrea tridentata.

nor 3'-Demethoxyisoguaiacin from Larrea tridentata Is a Potential Alternative against Multidrug-Resistant Bacteria Associated with Bovine Mastitis.

Bovine mastitis is one of the most common diseases in dairy cows, and it causes significant economic losses in dairy industries worldwide. Gram-positive and Gram-negative bacteria can cause bovine mastitis, and many of them have developed antimicrobial resistance. There is an urgent need for novel therapeutic options to treat the disease. Larrea tridentata-derived compounds represent an important potential alternative treatment. The aim of the present study was to isolate and characterize antibacterial compounds from Larrea tridentata against multidrug-resistant bacteria associated with bovine mastitis. The L. tridentata hydroalcoholic extract (LTHE) exhibited antibacterial activity. The extract was subjected to a bipartition, giving an aqueous fraction (moderate antibacterial activity) and an organic fraction (higher antibacterial activity). Chromatographic separation of the organic fraction enabled us to obtain four active sub-fractions. Chemical analyses through HPLC techniques were conducted for the LTHE, fractions, and sub-fraction Ltc1-F3, from which we isolated two compounds, characterized by 1H and 13C NMR analyses. Compound nor-3 demethoxyisoguaiacin exhibited the best antibacterial activity against the evaluated bacteria (MIC: 0.01-3.12 mg/mL; MBC: 0.02-3.12 mg/mL). The results indicated that nor-3 demethoxyisoguaiacin can be used as an alternative treatment for multidrug-resistant bacteria associated with mastitis.

Anti-hyperglycaemic effect and nutritional properties of an aqueous extract of Larrea divaricata Cav. (jarilla) in streptozotocin-induced diabetes in mice.

ETHNOPHARMACOLOGICAL RELEVANCE: Larrea divaricata Cav. (Zygophyllaceae) (jarilla) is a native plant of South America widely distributed across Argentina and used in popular medicine to treat diabetes and hypercholesterolemia by the Diaguita-Calchaquí, Amaichas, and Quilmes indigenous communities and by non-indigenous population (criollos) of Calamuchita, in the province of Córdoba, Argentina. L. divaricata has also proved to have anti-inflammatory properties. However, the antidiabetic effects and the nutritional properties of the aqueous extract (AE) of this plant remain to be scientifically determined. AIM OF THE STUDY: The aim of the present work was to evaluate the capacity of an aqueous extract of L. divaricata (AE) and its main compound nordihydroguaiaretic acid (NDGA) to modulate the glucose, cholesterol, triglycerides and oxidative stress levels in STZ-induced diabetes in mice. The general objective of the present work was to search for extracts that can be used as adjuvant therapy in for diabetes. The suitability of the extract to be used as a dietary supplement was also assessed by determining the proximate amount of fibre, lipids, proteins, and minerals. MATERIALS AND METHODS: Diabetes was induced in mice by administration of streptozotocin (STZ). AE and NDGA were administered by the oral route. The animals' glycaemia was periodically monitored in blood samples obtained from the tail vein. The glucose dehydrogenase method was used. The effect of the AE on cholesterol, triglycerides, oxidative stress, lipid peroxidation and reduced glutathione (GSH) levels were determined in plasma samples by spectrophotometric assays. RESULTS: In STZ-treated mice, AE significantly decreased glucose (33%, ****p < 0.0001) and cholesterol levels (32%, **p < 0.01). AE and NDGA decreased lipid peroxidation (30% and 38%, respectively, ****p < 0.0001), and increased GSH levels (20%, **p < 0.01). The effects of AE on glucose and lipid levels could not be ascribed to NDGA; however, this compound was involved in the extract antioxidant effects. The overall effects of AE were probably related to its antioxidant activity and to the anti-hyperglycaemic effect mainly mediated by flavonoids, fibre (carbohydrates) and mineral elements such as potassium, calcium, magnesium, and zinc. The AE protein content also confers the extract nutritional properties. CONCLUSIONS: These results support the hypothesis that AE could be used as a therapeutic adjuvant or as a nutritional supplement to control glucose levels and lipid metabolism in metabolic syndrome-associated diseases. Moreover, these results scientifically reinforce the popular use of the plant.

Larrea divaricata: anti-inflammatory and antioxidant effects of on macrophages and low density lipoproteins.

BACKGROUND: The oxidized low density lipoprotein (ox-LDL) contributes to inflammation and oxidative stress through the activation of macrophages under hyperglycemia contributing to the development of diabetes mellitus and to atherosclerosis. Plants are a source of effective and innocuous antioxidants. Larrea divaricata Cav. (Zygophyllaceae) is used in Argentina folk medicine for its anti-inflammatory properties. METHODS: The aim of this work was to study the antioxidant and anti-inflammatory effects of the aqueous extract (AE) of L. divaricata on macrophages under glucose stimulation and on human LDL and HDL particles under free radical generators. RESULTS: AE reduced the lipid peroxidation (17%), nitric oxide (NO) (47-50%), tumor necrosis factor-α (TNF-α) (32%) and free radicals (50%) induced by glucose on macrophages. Also prevented HDL nitration (28%), thus preserving its function and structure and inhibited LDL oxidation. The effect on the nitrosative stress was mainly driven by nordihydroguaiaretic acid (NDGA). CONCLUSIONS: These results suggest a potential usefulness of AE as an adjuvant phytotherapy in patients with diabetes mellitus and atherosclerosis.

Antiproliferative activity of aqueous and polyphenol-rich extracts of Larrea divaricata Cav. on a melanoma cell line.

Most of the deaths from skin cancer are caused by melanoma, a malignancy in which STAT3 plays a crucial role. The inhibition of STAT3 is considered a potential target to induce cell death, tumor regression and metastasis inhibition. The objective of this work was to evaluate the activity of the aqueous extract of Larrea divaricata (Aq), a fraction rich in polyphenols (EA),and the isolated compound quercetin-3-methyl ether (Q3ME) on B16F10 melanoma cells. The effects of Aq, EA and Q3ME were assessed on B16F10 cells by determining the proliferation, viability, apoptosis induction and the expression and phosphorylation of STAT3. The phytochemical composition of the extracts was determined by High Performance Liquid Chromatography. Aq, EA and Q3ME presented antiproliferative activity on B6F10 cells through p-STAT3 inhibition and early and late apoptosis induction (EC50 EA= ≤0.1 µg/ml; Aq= 316 ± 30 µg/ml; Q3ME= <0.1 µg/ml). L. divaricata could be considered for the development of adjuvant phytotherapies in melanoma treatment.

Larrea tridentata and its Biological Activities.

BACKGROUND: Larrea tridentata is a dominant shrub in the deserts of North America and is recognized for its various traditional uses. More than 50 traditional uses have been recorded. Regarding its chemical composition, the products of the mevalonate, shikimate, and malonate pathways are predominant. L. tridentata has nordihydroguaiaretic acid (NDGA), one of its most studied secondary metabolites that exhibited remarkable different biological activities: sequestration of reactive oxygen species, inhibition of lipoxygenases (LOX) and activation of the endogenous antioxidant response mediated by nuclear factor erythroid 2-related factor 2 (NRF2). OBJECTIVE AND METHODS: This review seeks to draw attention to metabolites other than NDGA and which also contribute to the various biological activities of L. tridentata. Therefore, the present review includes those reports focused on the pharmacological properties of the organic extracts of L. tridentata and its natural products with promising values. RESULTS AND CONCLUSION: Among the most promising and widely reported metabolites from L. tridentata, are: 3'-demethoxy-6-O-demethylisoguaiacin, 3'-O-methyldihydroguaiaretic acid, meso-dihydroguaiaretic acid, and tetra-O-methylnordihydroguaiaretic acid. These have been reported to exhibit antibacterial, antiprotozoal, anthelmintic, antifungal, antiviral, anticancer, and antioxidant activities.

UHPLC-ESI-OT-MS Phenolics Profiling, Free Radical Scavenging, Antibacterial and Nematicidal Activities of "Yellow-Brown Resins" from Larrea spp.

This research was designed to investigate the metabolite profiling, phenolics and flavonoids content and the potential antioxidant, antibacterial and nematicidal activities of "yellow-brown resins" from Larrea divaricata Cav (LdRe) and L. nitida Cav (LnRe). Metabolite profiling was obtained using an ultrahigh resolution liquid chromatography orbitrap MS analysis (UHPLC-ESI-OT-MS). The antioxidant properties were screened by four methods: 2,2-diphenyl-1-picrylhydrazyl assay (DPPH), trolox equivalent antioxidant activity assay (TEAC), ferric-reducing antioxidant power assay (FRAP) and lipid peroxidation in erythrocytes (LP). The antibacterial activity was evaluated according to the Clinical and Laboratory Standards Institute (CLSI) guidelines. In addition, the potential combinatory effect was analyzed with the fractional inhibitory concentration index (FICI) values using the checkerboard design. The nematicidal activity was carried out according to a standardized protocol. LdRe and LnRe showed a strong capture of the DPPH radical withvalues around 8.4 µg resin/mL; FRAP (1.69-1.94 mgTE/ g resin), TEAC (1.08-1.09 mgTE/g resin) and LP (81-82% at 100 µg of resin/mL) assays. A strong antimicrobial activity was displayed by both resins against methicillin-sensitive Staphylococcus aureus ATCC 25923(MSSA) and methicillin-resistant S. aureus ATCC 43300(MRSA) (MICs = 16-32 µg resin/mL). Additionally, the combination of LdRe or LnRe with the antibiotic cefotaxime showed an indifferent effect (FICI values = 1-1.25), however, this combinationcould be a potential strategy to reduce the drug doses, and in this way can be a potential alternative to reduce bacterial resistance. On the other hand, the resins showed a scarce nematicidal potential toward J2 Meloidogyne incognita; an important nematode infecting horticultural crops. Phenolics compounds were identified by UHPLC-PDA-OT-MS analysis, updating the knowledge on the chemical profile of these species. These results, together with the high content of quantified phenolics and flavonoids, allow the phenolics-enriched resins of these two Larrea species to be considered as a promising sustainable source of compounds of pharmacological interest.

Antigenotoxic, antiproliferative and antimetastatic properties of a combination of native medicinal plants from Argentina.

ETHNOPHARMACOLOGICAL RELEVANCE: Jarilla is the common name of an appreciated group of native plants from the semi-arid region in Argentina (Larrea cuneifolia Cav., Larrea divaricata Cav. and Zuccagnia punctata Cav.) that have been historically consumed to heal respiratory, musculoskeletal and skin ailments, as well as recommended for weakness/tiredness, hypertension, diabetes and cancer treatment. It was previously reported that some biological properties could be improved when these plants are used jointly. Infusions of a defined mixture, composed by three Jarilla species, L. cuneifolia: L. divaricata: Z. punctata (0.5:0.25:0.25) (HM2) showed synergistic and additive effect on antioxidant activity even after passing through the gastro-duodenal tract. AIM OF THE STUDY: The main purpose of this work was to evaluate antigenotoxic, antitumor, and anti-metastatic properties of the Jarilla species that grow in the Northwest of Argentina and a herbal combination of them. MATERIAL AND METHODS: Infusions of Jarilla mixture (HM2), and of each single plant species were prepared. Phenolic profiles of infusions were analyzed by HPLC-ESI-MS/MS and two relevant chemical markers were quantified. The antigenotoxic activity was evaluated by using the Ames test and the Cytokinesis-Block Micronucleus (CBMN) assay against direct mutagens. Evaluations of both cytotoxicity and antiproliferative effects were conducted on tumor and non-tumor cell lines. Both in vivo tumoral growth and metastasis inhibition were evaluated by using a carcinoma model on Balb/c mice. RESULTS: HM2 mix could suppress genetic and chromosome mutations induced by 4-nitro-o-phenylendiamine (4-NPD) and doxorubicin. Herbal mixture and single plant infusions showed cytotoxic effect against mammary, uterus, and brain tumoral cells without a selective action vs normal human cell line. HM2 mix was able to reduce mammary tumor mass on the Balb/c mice model and showed a significant reduction in the number of metastatic nodules in the lungs. CONCLUSIONS: Our results suggest that the combinations of three Jarilla species from northwest Argentina would be a promising alternative to treat or slow down the development of chronic diseases, such as cancer.

Molecular mimicry between Larrea divaricata Cav. plant and a reference strain of Pseudomonas aeruginosa.

Currently, the world health sector faces a big problem due to the increase of bacterial strains resistant to antibiotics. In 2017, the World Health Organization reported a list of resistant bacteria, among which Pseudomonas aeruginosa was present. This opportunistic pathogen is associated to nosocomial infections, and no effective vaccines against this bacterium have been found. Larrea divaricata Cav. (jarilla) is a shrub highly distributed in America and widely used in folk medicine. In our laboratory, cross-reactivity of antibodies obtained from the recognition of jarilla proteins against proteins from gram-negative bacteria has been demonstrated. The objective of this study was to study the cross-reactivity of anti-L. divaricata antibodies with P. aeruginosa extracellular proteins in order to find an innocuous prophylactic therapy against this nosocomial pathogen. We observed that antibodies generated by proteins from jarilla crude extract recognized antigenic determinants present in extracellular proteins of P. aeruginosa. However, further studies are needed to investigate the neutralizing capacity of these antibodies on the specific enzymatic proteins involved in the pathogenicity of this bacterium.

Larrea divaricata Cav. aqueous extract and nordihydroguariaretic acid modulate oxidative stress in submandibular glands of diabetic rats: a buccal protective in diabetes.

BACKGROUND: Oxidative stress is an imbalance between the levels of reactive oxygen species (ROS), reactive nitrogen species (RNS) and endogenous antioxidants. The aetiology and pathogenesis of several oral diseases are attributed to this process. The antioxidant enzymes secreted in the saliva by submandibular glands maintain oral health through the scavenging of ROS. The objective of this work was to study the capacity of an aqueous extract of L. divaricata (AE), and its majority compound, nordihydroguariaretic acid (NDGA), to modulate the pro-oxidant/antioxidant status in submandibular glands in a model of oxidative stress induced by streptozotocin (STZ) in rats. METHODS: To induce oxidative stress with STZ, a group of animals was treated i.p. with 1 X PBS (control group) and other group was injected i.p. once with STZ (60 mg/kg). Ten days after the treatment, blood samples were taken from the tail vain to determine the glucose levels. Animals with glucose values ≥300 mg/ml were selected. The submandibular glands of control and STZ treated animals were incubated with either the AE (500 µg/ml) or with NDGA (1.5 µg/ml), and the content of malondialdehyde (MDA), protein carbonyl groups, ROS and RNS, and the activity and expression of peroxidase (Px), superoxide dismutase (SOD) and inducible nitric oxide synthase (iNOS) were assayed. RESULTS: AE decreased the levels of MDA (##P < 0.01) and protein carbonyl groups (#P < 0.05), and modulated the levels of ROS such as hydrogen peroxide (H2O2)(##P < 0.01), superoxide anion (O2.-) (#P < 0.05) and nitric oxide (NO) (#P < 0.05) in relation to the modulation of Px and iNOS expression. NDGA was found to be involved in these effects. CONCLUSIONS: The antioxidant activity of the AE in the submandibular glands would allow the maintenance of the antioxidant pool to prevent oral oxidative diseases.

Creosote Bush (Larrea tridentata) Extract Assessment as a Green Antioxidant for Biodiesel.

In this work, the antioxidant properties of methanolic extract of Larrea tridentata were assessed through the free radical scavenging method, ferric reducing antioxidant power and oxygen radical absorbance capacity. The phenolic acids content in the extract was quantified by high-performance liquid chromatography (HPLC) and the total phenol content by the Folin-Ciocalteu method. The extract was used as an antioxidant in biodiesel from canola oil composed mostly by fatty acid methyl esters identified and quantified by gas chromatography-mass spectrophotometry (GC-MS). The performance of the extract as an antioxidant was assessed by the oxidative stability index (OSI) with a Rancimat equipment at 100, 110, 120 and 130 °C. Additionally, the change of the peroxide value (PV) and the higher heating value under conditions of oxidative stress at 100 °C and air injection were measured. The antioxidant capacity of the extract reached 50,000 TAEC (micromole of Trolox antioxidant equivalent capacity per gram). The biodiesel was constituted by more than 70% of unsaturated fatty acid methyl esters (FAME), mainly methyl oleate. The time needed to reach a PV of 100 meqO2/kg was almost four times longer with an antioxidant concentration of 250 mg/L than the blank. The biodiesel showed an OSI time of 1.25 h at 110 °C, while it increased to 8.8, 15.89 and 32.27 h with the antioxidant at concentrations of 250, 500 and 1000 mg/L, respectively. The methanolic Larrea tridentata extract proved to have an antioxidant capacity and it is a green antioxidant in biodiesel to increase its oxidative stability. According to the results obtained, the L. tridentata methanolic extract is an alternative to the commercial synthetic antioxidants used in biodiesel nowadays.

Enhanced oxidative stability of meat by including tannin-rich leaves of woody plants in goat diet.

Objective: The aim of this study was to evaluate the effect of dietary incorporation of tannin-rich woody species on meat oxidative stability, carcass traits and meat quality in goats. Methods: Two tannin-rich species were tested using a three-treatments feeding trial, where treatments consisted of: Larrea divaricata and Acacia aroma both at 12.5% in dry matter basis of the diet and a control diet (alfalfa hay). All feeding diets were iso-protein and iso-energy. Carcass conformation, carcass compactness, carcass fatness and subcutaneous fat deposition were evaluated. Intake, liveweigh, Longissimus thoracis et lumborum muscles of goats were analyzed in order to evaluate quality parameters such as pH value, instrumental color evaluation, water holding capacity, total phenolic content, antioxidant activity, meat oxidative stability and fatty acid profiles in meat. Results: Feed intake, liveweight gain, carcass and meat traits did not differ among treatments. Changes in meat lipid profile among treatments were observed for oleic and elaidic acid contents. Meat total phenolic content and antioxidant activity did not differ among treatments; although, meat oxidative status after storage at room temperature, as well as under refrigerated and frozen conditions were different between control and both supplemented groups. Conclusion: The inclusion of Acacia aroma and Larrea divaricata leaves in goat diet enhanced meat oxidative stability. Modulation of the ruminal biohydrogenation of fatty acids produced by condensed tannins of these plant species need to be further investigated.

Approaches to the mechanism of antifungal activity of Zuccagnia punctata-Larrea nitida bi-herbal combination.

BACKGROUND: In our previous study the synergism of four combinations of Zuccagnia punctata (ZpE) and Larrea nitida (LnE) exudates with the reliable statistical-based MixLow method was assessed, and the markers of the most anti-C. albicans synergistic ZpE-LnE bi-herbal combination were quantified according to European Medicines Agency (EMA). PURPOSE: To study the mechanisms of action as well as the cytotoxic properties of the ZpE-LnE most synergistic combination found in the previous work. MATERIALS AND METHODS: Minimum Fungicidal Concentration (MFC) and rate of killing of ZpE-LnE were assessed with the microbroth dilution and the time-kill assays respectively. Morphological alterations were observed with both confocal and fluorescence microscopy on the yeast Schizosaccharomyces pombe. The ergosterol exogenous assay, the quantification of ergosterol, the sorbitol as well as glucan synthase (GS) and chitin synthase (ChS) assays were used to detect the effects on the fungal membrane and cell wall respectively. The capacity of ZpE-LnE of inhibiting Candida virulence factors was assessed with previously reported methods. The effect of ZpE-LnE and of ZpE or LnE alone on cell viability was determined on human hepatoma cells line Huh7. RESULTS: ZpE-Ln E was fungicidal killing C. albicans in a shorter time than amphotericin B and produced malformations in S. pombe cells. ZpE-LnE showed to bind to ergosterol but not to inhibit any step of the ergosterol biosynthesis. ZpE-LnE showed a low or moderate capacity of inhibiting GS and ChS. Regarding inhibition of virulence factors, ZpE-LnE significantly decreased the capacity of adhesion to eukaryotic buccal epithelial cells (BECs), did not inhibit the germ tube formation and inhibited the secretion of phospholipases and proteinases but not of haemolysins. ZpE-LnE demonstrated very low toxicity on Huh7 cells, much lower than that each extract alone. CONCLUSION: The fungicidal properties of ZpE-LnE against C. albicans, its dual mechanism of action targeting the fungal membrane's ergosterol as well as the cell wall, its capacity of inhibiting several important virulence factors added to its low toxicity, make ZpE-LnE a good candidate for the development of a new antifungal bi-Herbal Medicinal Product.

Dinámica de la diversidad temporal de los hongos micorrícicos arbusculares de Larrea tridentata (Sesse & Mocino ex DC) Coville en un ecosistema semiárido / Temporal diversity dynamics of the arbuscular mycorrhizal fungi of Larrea tridentata (Sesse & Mocino ex DC) Coville in a semi-arid ecosystem

Los hongos micorrícicos arbusculares (HMA) de los ambientes áridos y semiáridos son importantes para el desarrollo de las plantas que crecen bajo estrés biótico y abiótico en áreas naturales o en agroecosistemas. Existe poca información sobre la diversidad temporal de los HMA en plantas perennes de ecosistemas áridos en el norte de México. En este estudiose evaluaron la colonización micorrícica y la diversidad temporal de los HMA en la rizosfera de Larrea tridentata, planta perenne de amplia distribución en el Desierto Chihuahuense. Se obtuvieron muestras de la rizosfera y de raíces de 15 plantas, en 3 fechas de muestreo del año 2015. Se encontró un total de 17 especies de HMA, distribuidas en 12 géneros y 7 familias dentro del phylum Glomeromycota. La especie más abundante fue Funneliformis geosporum. Esta especie pertenece a la familia Glomeraceae, la única que estuvo representada con varios géneros en L. tridentata. El mayor porcentaje de micorrización se presentó en febrero, con un 83,22%, en septiembre fue del 75,27% y en mayo del 65,27%. El muestreo realizado en febrero presentó el mayor número de especies (16), seguido por el de mayo (15) y el de septiembre (12). El análisis estadístico mostró diferencias significativas en el número de esporas entre los muestreos de febrero y los de mayo y septiembre.

Arbuscular mycorrhizal fungi (AMF) of arid and semiarid ecosystems are important for the development of plants that grow under biotic stress in wild or in agro-ecosystems. There is little information on the temporal diversity of these organisms in perennial plants from arid ecosystems in northern Mexico. On this study, the mycorrhizal colonization and the temporal diversity of AMF in the rhizosphere of Larrea tridentata, perennial plant abundant in the Chihuahuan Desert region were explored. Samples of the rhizosphere and roots of fifteen plants in each of the three sampling dates during the 2015 year were obtained. A total of 17 species of HMA belonging to 12 genera and 7 families within the phylum Glomeromycota in all three sampling dates were found. Funneliformis geosporum was the dominant species belonging to the family Glomeraceae which possess the highest genera number on L. tridentata.The highest mycorrhization percentage was in February with 83.22, followed by September and May with 75.27 and 65.27%, respectively. A maximum of 16 AM fungal species were isolated and identified from L. tridentata rhizosphere in February, 15 species in May and 12 species in September. Statistical analysis showed significant differences between sampling dates in the spores number.

Morphoanatomical and histochemical characterization of Larrea species from Northwestern of Argentina

Abstract Larrea divaricata Cav., L. cuneifolia Cav. and L. nitida Cav., Zygophyllaceae, are evergreen xerophytic shrubs occurring in Northwestern Argentina used in traditional medicine. The aim of this work was to characterize the morphology, anatomy and histochemistry of the vegetative organs of three Larrea species by light and scanning electron microscopy in order to provide supporting data for their correct identification and to determine the site of synthesis and accumulation of its main active compounds. The shape, number and percentage of coalescence of leaflets, presence or absence of mucrones and rachis and the shape of the stipules represented the main botanical differences between the studied Larrea species. Anatomically three species presented amphystomatic leaves, with thick resinous slightly striated cuticle with resinous deposits, polygonal epidermal cells with straight anticlinal walls, ciclocytic, brachy-paracytic and paracytic stomatal types, non-glandular trichomes and isolateral mesophyll. The position and abundance of the sclerenchyma at the mid vein and petiole transection allows the differentiation of the three species, been more abundant in L. cuneifolia. Secondary phloem and parenchyma cells presented abundant calcium oxalate druses and solitary rhomboidal crystals. Epidermal cells and cuticle layer of leaflets and stipules of the three species presented amber resin deposits and content which stained positively for polysaccharides, phenolic compounds, flavonoids and tannins, while mesophyll palisade cells showed small refracting droplets stained positively for lipophilic substances.

Development of pH-responsive biopolymer-silica composites loaded with Larrea divaricata Cav. extract with antioxidant activity.

A detailed study of biomaterials is mandatory to comprehend their feasible biomedical applications in terms of drug delivery and tissue regeneration. Particularly, mucoadhesive biopolymers such as chitosan (chi) and carboxymethylcellulose (CMC) have become interesting biomaterials regards to their biocompatibility and non-toxicity for oral mucosal drug delivery. In this work, pH-responsive biopolymer-silica composites (Chi-SiO2, Chi-CMC-SiO2) were developed. These two types of composites presented a different swelling behavior due to the environmental pH. Moreover, the nanocomposites were loaded with aqueous Larrea divaricata Cav. extract (Ld), a South American plant which presents antioxidant properties suitable for the treatment of gingivoperiodontal diseases. Chi-CMC-SiO2 composites showed the highest incorporation and reached the 100% of extract release in almost 4 days while they preserved their antioxidant properties. In this study, thermal and swelling behavior were pointed out to show the distinct water-composite interaction and therefore to evaluate their mucoadhesivity. Furthermore, a cytotoxicity test with 3T3 fibroblasts was assessed, showing that in both composites the addition of Larrea divaricata Cav. extract increased fibroblast proliferation. Lastly, preliminary in vitro studies were performed with simulated body fluids. Indeed, SEM-EDS analysis indicated that only chi-SiO2 composite may provide an environment for possible biomineralization while the addition of CMC to the composites discouraged calcium accumulation. In conclusion, the development of bioactive composites could promote the regeneration of periodontal tissue damaged throughout periodontal disease and the presence of silica nanoparticles could provide an environment for biomineralization.