Anti-Streptococcal activity of Brazilian Amazon Rain Forest plant extracts presents potential for preventive strategies against dental caries

Abstract

Caries is a global public health problem, whose control requires the introduction of low-cost treatments, such as strong prevention strategies, minimally invasive techniques and chemical prevention agents. Nature plays an important role as a source of new antibacterial substances that can be used in the prevention of caries, and Brazil is the richest country in terms of biodiversity.Objective In this study, the disk diffusion method (DDM) was used to screen over 2,000 Brazilian Amazon plant extracts against Streptococcus mutans. Material and Methods Seventeen active plant extracts were identified and fractionated. Extracts and their fractions, obtained by liquid-liquid partition, were tested in the DDM assay and in the microdilution broth assay (MBA) to determine their minimal inhibitory concentrations (MICs) and minimal bactericidal concentrations (MBCs). The extracts were also subjected to antioxidant analysis by thin layer chromatography. Results EB271, obtained from Casearia spruceana, showed significant activity against the bacterium in the DDM assay (20.67±0.52 mm), as did EB1129, obtained from Psychotria sp. (Rubiaceae) (15.04±2.29 mm). EB1493, obtained from Ipomoea alba, was the only extract to show strong activity against Streptococcus mutans (0.08 mg/mL<MIC<0.16 mg/mL; MBC=0.16 mg/mL) in the MBA. Conclusions The active extracts, discovered in the Amazon rain forest, show potential as sources of new antibacterial agents for use as chemical coadjuvants in prevention strategies to treat caries.

Analysis of Brazilian Plant Extracts as Potential Source of Antioxidant Natural Products Using Bench-Top Assays

“…Still, high-throughput assays are the fastest, inexpensive and easily expanding way of analyzing the vast Amazon rain forest diversity that remains unexploited to today. 7 Our group aimed at the chemical screening of 895 organic and aqueous extracts obtained from plants found in the Amazon rain forest that have been preciously screened for their biological, [8][9][10] pharmacological and toxicological activities. [11][12][13][14][15][16] The extracts were tested for their free radical scavenging and antioxidant activities, as well as screened for the presence of alkaloids, anthraquinones and cardenolides, some of the most active classes of phytochemicals.…”

Zerumbone From Zingiber zerumbet (L.) Smith: A Potential Prophylactic and Therapeutic Agent Against The Cariogenic Bacterium Streptococcus mutans

“…As a matter of fact, few reports have shown natural biomolecules antimicrobial activity against the S. mutans and the majority demonstrated weak antibacterial action based on the classification set out above [28][29][30].A recent study tested around two thousand plant extracts from Amazon region against S. mutans (ATCC 25175) and, from this number, seventeen displayed antimicrobial activity, but only the extract obtained from Ipomoea alba L. sp (Convolvulaceae) showed antimicrobial activity considered strong (MBC> 160µg/mL) [31].Takarada et al [32] and Aguiar et al [33] evaluated the anti-S. mutans activity of essential oils from the following plants: Romarinus officinalis L., Melaleuca alternifólia, Lavandula officinalis, Leptosperfum scoparium, Eucalyptus radiate, Ageratum conyzoides, Artemisia camphorata Vill., Bidens sulphurea, Foeniculum vulgare Mill., Lippia alba, Ocimum gratissimum L., Pelargonium graveolens, Syzygium aromaticum and Tagetes erecta L. The results showed MICs ranging from 500 to10,000 μg/mL, activities considered weak compared to our data. Therefore, these studies corroborate the strong bioactive potential of the zerumbone as anticariogenic agent, which could be a good substrate to be used in prophylactic and therapeutic formulations against tooth decay.…”

ent-Kaurenoic acid-rich extract from Mikania glomerata: In vitro activity against bacteria responsible for dental caries

“…Moreover, the addition of such extracts to oral products like mouthwashes and dentifrices constitutes an important strategy in caries control [6,7].…”