Ten banana (Musa spp.) cultivars were studied for their antimicrobial properties. Three plant parts (corm, pseudostem and leaves) were collected separately and extracted with different solvents, viz., hexane, acetone, ethanol and water. The 50% inhibitory concentration (IC₅₀) was evaluated using a broth microdilution assay. Eight human bacterial and one fungal pathogen were tested. Acetone and ethanol extract(s) often exhibited significant antimicrobial activity, while hexane extracts were less active. Aqueous extracts often showed microbial growth, possibly by endophytes. Leaf extracts were most active, followed by pseudostem, and corm was least active. All the tested banana cultivars were found to contain antimicrobials, as demonstrated by inhibition of selected human pathogens. However, cultivars such as Dole, Saba, Fougamou, Namwah Khom, Pelipita and Mbwazirume showed a broad-spectrum activity, inhibiting all tested pathogens. Other cultivars such as Petit Naine and Kluai Tiparot showed a narrow-spectrum activity, including antibiofilm activity against Candida albicans. Our results support the use of different parts of banana plants in traditional human medicine for infections, including diarrhea and dysentery, and some sexually transmitted diseases, as well as for packaging spoilable materials like food.

The aim of this research was to characterize and compare two types of calli from leaf explants of Coffea arabica (cultivar Catiguá). Cells of different types of callus were successfully characterized regarding viability and internal and external morphological characteristics. It was obtained two morphologically distinct types of callus: (i) yellow friable and (ii) transparent watery. The yellow friable calli showed higher cell viability and embryogenic characteristics. Scanning and transmission electron microscopy showed embryogenic characteristics in cells of the yellow friable calli evidenced by the presence of small and isodiametric cells, while transparent watery calli showed elongated cells and large cytoplasm vacuolization

Chikungunya and yellow fever virus cause vector-borne viral diseases in humans. There is currently no specific antiviral drug for either of these diseases. Banana plants are used in traditional medicine for treating viral diseases such as measles and chickenpox. Therefore, we tested selected banana cultivars for their antiviral but also cytotoxic properties. Different parts such as leaf, pseudostem and corm, collected separately and extracted with four different solvents (hexane, acetone, ethanol, and water), were tested for in vitro antiviral activity against Chikungunya virus (CHIKV), enterovirus 71 (EV71), and yellow fever virus (YFV). Extracts prepared with acetone and ethanol from leaf parts of several cultivars exhibited strong (EC₅₀ around 10 μg/mL) anti-CHIKV activity. Interestingly, none of the banana plant extracts (concentration 1–100 µg/mL) were active against EV71. Activity against YFV was restricted to two cultivars: Namwa Khom–Pseudostem–Ethanol (5.9 ± 5.4), Namwa Khom–Corm–Ethanol (0.79 ± 0.1) and Fougamou–Corm–Acetone (2.5 ± 1.5). In most cases, the cytotoxic activity of the extracts was generally 5- to 10-fold lower than the antiviral activity, suggesting a reasonable therapeutic window.

In vitro germination, callus induction and phenolic compounds contents from Pyrostegia venusta (Ker Gawl.) Miers

The aim of this study was to evaluate the antimicrobial activity in vitro of ethanolic extracts of Banisteriopsis anisandra. Tests were performed using the extracts overlay method in the culture medium for phytopathogenic fungi Rhizoctonia solani and Fusarium oxysporum, and disk diffusion for the microorganisms Staphylococcus aureus and Candida albicans. Ethanolic extracts from leaves were prepared by maceration (extract I) and decoction (extract II) at 430.0, 215.0 and 107.5 mg/mL. The growth inhibition of R. solani and F. oxysporum was determined by calculating the mycelia growth speed rate (MGSR) and, in relation C. albicans and S. aureus, it was determined by measuring the inhibition halos. Extracts that caused significant inhibition were also tested at 86.0, 64.5, 43.0 and 21.5 mg/mL for C. albicans and S. aureus. Both extracts showed inhibitory activity on the microorganisms studied. Rizoctonia solani showed lower MGSR in the presence of extract II (107.5 mg/mL) and Fusarium oxysporum showed slight MGSR reduction in the presence of extract I (107.5 mg/mL) and II (107.5 and 215 mg/mL). Ethanolic extracts I and II inhibited the growth of C. albicans, with the highest rates of inhibition observed in the presence of extract II (215.0 mg/mL). For S. aureus, the highest inhibitory activity was observed in the presence of ethanolic extract II, prepared by decoction at 430.0 mg/mL. Results showed a promising antimicrobial activity of extracts of B. anisandra, which may contribute to further studies leading to a future development of medicines to treat human and plant diseases caused by these organisms.