Bixa orellana L. (Achiote, Annatto) as an antimicrobial agent: A scoping review of its efficiency and technological prospecting.

ETHNOPHARMACOLOGICAL RELEVANCE: Bixa orellana L. is reported to have numerous applications in traditional medicine and pharmacological properties such as wound healing, analgesic, hemostatic, and antioxidant activities. Recently, the literature has shown scientific interest of its antimicrobial properties aiming the development of cost-effective phytotherapeutic agents. However, no literature are available in witch the antimicrobial and technological prospecting are summarized. AIM OF STUDY: This study aimed to systematically review articles and patents related to the antimicrobial activity of B. orellana. METHODS: The review followed the guidelines proposed by The Joanna Briggs Institute and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Two reviewers performed a literature search up to November 2021 in eight databases: Medline (PubMed), Scopus, Scifinder, Web of Science, Cochrane, Embase, Scielo, and Biblioteca Virtual em Saúde. The following databases for the patent search were analyzed: United States Patent and Trademark Office (USPTO), Google Patents, National Institute of Industrial Property (INPI), World Intellectual Property Organization (WIPO), and Espacenet (European Patent Office, EPO). The grey literature was searched using the ProQuest Dissertations and Periódicos Capes Theses database. The methodological quality and risk of bias in the included studies were carried out using Review Manager (RevMan) 5.3.5. RESULTS: After analyzing the 47 studies and five patents fulfilled all the criteria and were included in the present investigation. The evidence suggests that this herbal medicine is effective against several fungi, Gram-positive and Gram-negative bacteria, being more effective to Gram-negative bacteria. Regarding the risk of bias and methodological quality analysis, most studies a high risk of bias related to random sequence generation and allocation concealment. CONCLUSION: Up to now, the evidence in the literature suggests that the use of B. orellana preparations for antimicrobial preparations has some effectiveness. However, further research is needed using standard B. orellana preparations to determine their effectiveness as antimicrobial agents and expanding their application at an industrial level, in addition in vivo studies are needed for this confirmation.

Gastroprotective activity of hydroalcoholic extract of the leaves of Urera baccifera in rodents.

ETHNOPHARMACOLOGICAL IMPORTANCE: The species Urera baccifera (L.) Gaudich. ex Wedd. (Urticaceae) is native to the Americas and is distributed widely throughout Brazil, where it is known as urtiga-brava, urtiga-vermelha, or urtigão. The leaves are often used as anti-inflammatory and antirheumatic agents and for the treatment of gastric disorders. However, the pharmacological mode of action underlying the gastroprotection induced by this species has not been investigated. AIM OF THE STUDY: To contribute to the knowledge of the gastroprotective mode of action of the hydroalcoholic extract of U. baccifera (HEU) leaves. MATERIALS AND METHODS: Antiulcerogenic effect of HEU against ethanol-induced acute gastric ulcer was evaluated in rats and mice at doses of 3-300 mg/kg. NO-synthase inhibitor (L-NAME), SH blocker (NEM), cyclooxygenase inhibitor (indomethacin) and alpha 2-adrenergic receptor antagonist yohimbine were used to evaluate the participation of cytoprotective factors in HEU gastroprotection. Moreover, the levels of reduced gluthatione (GSH) and cytokines (TNF, IL-6, IL4 and IL-10), as well as the enzymatic activity of gluthatione S-transferase (GST), myeloperoxidase (MPO), superoxide dismutase (SOD) and catalase (CAT) were measure. Moreover, the samples were analyzed histologically and the antisecretory capability of HEU were quantified using pylorus ligated rats. RESULTS: The phytochemical analysis of HEU (UPLC/ESI-IT-MS) identified the flavonoids diosmetin and apigenin glucuronide. Furthermore, HEU decreased the occurrence of ethanol-induced ulcers at 30 and 300 mg/kg by 57% and 66%, respectively, compared with the vehicle. The gastroprotective effects were accompanied by increased GSH levels and GST and SOD activity as well as by reduced MPO activity in vivo and in vitro, revealing antioxidant effects and inhibition of neutrophil infiltration. The beneficial effects of 30 and 300 mg/kg HEU were also observed upon histological analyses. Regarding the mode of action, the gastroprotective effect of HEU was abolished by the pre-administration of L-NAME, NEM, indomethacin or yohimbine. Moreover, HEU was able to decrease the IL-6, IL-4 and IL-10 in ulcerated tissue, as well as the pepsin activity of the gastric juice in pylorus-ligated rats. CONCLUSION: Together, the results confirmed that the gastroprotection elicited by HEU was due reduction in oxidative damage, neutrophil migration, and peptic activity. This work validates the popular use of U. baccifera to treat gastric disorders and supports important future research for the identification of gastroprotective molecules from this species.

Antiproliferative Effect of Urera baccifera Leaves Against Ovarian Carcinoma Cell Line (OVCAR-3)

Abstract Natural products, especially phytochemicals, have been extensively studies and have exhibited important antiproliferative effects. The American native species Urera baccifera (L.) Gaudich. ex Wedd. (Urticaceae) is widely distributed in Brazil, where it is known as urtiga-vermelha or urtigão. The leaves are popularly used as anti-inflammatory, antirheumatic and in the treatment of gastric disorders. However, the antiproliferative potential of this plant against human tumor cells remain to be elucidated. In this study, we evaluated the antiproliferative effects of U. baccifera leaves extracts and fractions against a panel of human tumor cell lines in vitro besides a chemical evaluation of the most active sample by mass spectrometry (ESI-IT-MSn). The hydroalcoholic extract was inactive while dichloromethane extract showed moderate cytostatic activity against ovarian carcinoma cell line (OVCAR-3, GI50 = 1.5 μg/mL). More, the ethyl acetate and n-butanol fractions did not show important activity against tumour cell while the dichloromethane and hexane fractions showed moderate cytostatic activity against ovarian tumor cell line (OVCAR-3, GI50 = 12.7 and 9.4 μg/mL, respectively). Finally, the chemical profile evaluated by mass spectrometry (ESI-IT-MSn) allowed the detection of flavonoids in the HEU and hydroxylated fatty acid in DEU that can explain partially the biological effects observed. This is the first report of the antiproliferative effects of U. baccifera, and DEU has shown potential as a promising source of bioactive compounds.

Denture disinfection using Salvia officinalis L: microbial load and selected properties of PMMA

Denture use may aggravate the occurrence of oral infections, considering it enhances microbial adherence. Aim: This study assessed the reduction of microbial loads of Candida albicans, Staphylococcus aureus, and Klebsiella oxytoca by disinfecting the polymethylmethacrylate (PMMA) of complete dentures with hydroalcoholic extract of Salvia officinalis. Additionally, the effect of such extract on the properties of PMMA was examined. Methods: Microorganisms were isolated from saliva samples collected from complete denture wearers. The hydroalcoholic extract of S. officinalis was produced according to the Brazilian Pharmacopoeia 5. The PMMA specimens (n=188) were immersed in microbial inoculum and incubated at 37°C for 16 hours per day. Then, they were subjected to a disinfection protocol for 30 days. The specimens were divided into five treatment groups: sterile saline solution (0.85%; control), 0.2% chlorhexidine digluconate, and hydroalcoholic extract of S. officinalis (0.2%, 0.8%, and 1.16%). Microorganism adherence to the PMMA surface was also assessed, as well as surface roughness (Ra in µm) and color stability of the PMMA (mean ΔE). Changes in microbial load and surface roughness after the disinfection protocol were verified with paired t-test. Substances at day 10, adherence, and color stability were compared by the Kruskall-Wallis and Mann-Whitney tests, and one-way ANOVA was used to compare substances at the beginning and end of the experiment (α=0.05). Results: The 1.16% S. officinalis extract significantly reduced the microbial load of all the microorganisms after 30 days of disinfection (p<0.05). The microbial load of K. oxytoca was also reduced at lower concentrations of the S. officinalis extract (0.2% and 0.8%) (p<0.02). Antimicrobial and anti-adherent effects against microorganisms isolated from the oral cavity were observed. There was no significant change in surface roughness (p>0.05) and color stability was significantly higher in the control group (p<0.0001). Conclusions: The hydroalcoholic extract of S. officinalis may be used as a disinfectant solution for dentures