Evaluation of Selected Medicinal Plants Extracted in Different Ethanol Concentrations for Antibacterial Activity against Human Pathogens

Medicinal plant extracts prepared with selected ethanol concentrations from eight species, Peumus boldus (boldo leaf), Agathosma betulina (buchu leaf), Echinacea angustifolia (echinacea root), Humulus lupulus (hops strobile), Glycyrrhiza glabra (licorice root), Mahonia aquifolium (Oregon grape root), Usnea barbata (usnea lichen), and Anemopsis californica (yerba mansa root), were screened for antibacterial activity against four Gram-positive and four Gram-negative pathogens. The antibacterial activity of the extracts (50, 70, and 90% ethanol) was evaluated using a standard well assay and microbroth dilution method. Minimum bactericidal concentrations (MBCs) were also determined for each extract. Plant extracts showed strong antibacterial action against Gram-positive bacteria, Staphylococcus aureus, methicillin resistant Staphylococcus aureus (MRSA), Staphylococcus epidermidis and Streptococcus pyogenes, while negligible to no inhibitory activity against Gram-negative bacteria; Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa and Salmonella enteritidis was observed. Among the plant extracts, the boldo, hops, licorice and yerba mansa exhibited a strong antibacterial action at all three ethanol concentrations. Of these four, hops showed the strongest activity at 90% ethanol. Echinacea angustifolia extracts did not show any considerable antibacterial activity, while usnea showed strong activity only at 90% against S. epidermis. Except Echinacea angustifolia and usnea, the plant extracts were strongly inhibitory towards the MRSA strain. Buchu, yerba mansa and Oregon grape showed higher activity at 50% or 70% on MRSA. MBCs varied from 1/4 to \u3e1/256 dilution levels and were in agreement with well assay results. The results suggest that the extracts of boldo, hops, licorice and yerba mansa could be considered as potentially effective antibacterial agents against Gram-positive bacteria including MRSA. For hops, buchu, Oregon grape and usnea, the activity is dependent on the concentration of ethanol used in the extraction procedure. The ratio of ethanol/water mixture used for extraction of medicinal plants is an important factor to obtain optimum antibacterial activity

Chemical compositions and antimicrobial activities of Athrixia phylicoides DC. (bush tea), Monsonia burkeana (special tea) and synergistic effects of both combined herbal teas

AbstractObjectiveTo determine the chemical compositions and evaluate the antimicrobial activity of bush tea (Athrixia phylicoides DC.), special tea (Monsonia burkeana) and synergy (combination of bush tea and special tea).MethodsTotal polyphenols were determined using the methods reported by Singleton and Rossi (1965) and modified by Waterman and Mole (1994). Tannins were determined using vanillin HCL methods described by Prince et al. (1978). Total antioxidants were determined using the methods described by Awika et al. (2004). The micro dilution technique using 96-well micro-plates, as described by Eloff (1998) was used to obtain the minimum inhibition concentration (MIC) and minimum microbicidal concentration (MMC) values of the ethanol extracts against the microorganisms under study. The microbes strain used was Gram negative bacteria such as Escherichia coli, Klebsiella oxytoca, Proteus vulgaris, Serratia marcescens, Salmonella typhi, Klebsiella pneumonia; Gram positive bacteria such as Bacillus cereus, Staphylococcus aureus and a fungus Candida albicans.ResultsThe results demonstrated that special tea contains significantly higher content of total polyphenols (8.34 mg/100 g) and total antioxidant (0.83 mg/100 g) as compared to bush tea [total polyphenols (6.41 mg/100g) and total antioxidant (0.63 mg/100g)] and combination of bush tea and special tea [total polyphenols (6.42 mg/100 g) and total antioxidant (0.64 mg/100 g)]. There was no significant difference in tannins between bush tea, special tea and synergy. The results of antimicrobial activity (MIC and MMC) demonstrated that the ethanol extracts of bush tea, special tea and synergy possessed antimicrobial activity against all microorganisms at different zones. The MIC of bush tea ranged from 1.56 to 12.50 mg/mL while the MMC ranged from 0.78 to 12.50 mg/mL. Special tea's MIC ranged from 0.39 to 12.50 mg/mL while the MMC ranged from 0.01 to 12.50 mg/mL. The MIC of synergy ranged from 3.13 to 12.50 mg/mL while the MMC ranged from 3.13 to 12.50 mg/mL without positive synergistic effect recorded.ConclusionsBoth bush and special tea contain total polyphenols, total antioxidants and tannins with special tea containing a significantly higher total polyphenols and total antioxidant as compared to bush tea and synergy. Bush tea, special tea and synergy possess antimicrobial activity at various degrees

Anthelmintic activity of trans-cinnamaldehyde and A- and B-type proanthocyanidins derived from cinnamon (Cinnamomum verum)

Cinnamon (Cinnamomum verum) has been shown to have anti-inflammatory and antimicrobial properties, but effects on parasitic worms of the intestine have not been investigated. Here, extracts of cinnamon bark were shown to have potent in vitro anthelmintic properties against the swine nematode Ascaris suum. Analysis of the extract revealed high concentrations of proanthocyanidins (PAC) and trans-cinnamaldehyde (CA). The PAC were subjected to thiolysis and HPLC-MS analysis which demonstrated that they were exclusively procyanidins, had a mean degree of polymerization of 5.2 and 21% of their inter-flavan-3-ol links were A-type linkages. Purification of the PAC revealed that whilst they had activity against A. suum, most of the potency of the extract derived from CA. Trichuris suis and Oesophagostomum dentatum larvae were similarly susceptible to CA. To test whether CA could reduce A. suum infection in pigs in vivo, CA was administered daily in the diet or as a targeted, encapsulated dose. However, infection was not significantly reduced. It is proposed that the rapid absorption or metabolism of CA in vivo may prevent it from being present in sufficient concentrations in situ to exert efficacy. Therefore, further work should focus on whether formulation of CA can enhance its activity against internal parasites

Assessment of service quality perceived by passengers at Bandaranayake International Airport, Katunayake

Service quality at airports as perceived by air passengers is a comparison between their expectations and airport’s actual performance which is measured by the performance ofservice delivery ofthe airport. Delivering high quality service to passengers by airports is vital for their market competitiveness and ultimately for promoting the image ofthe country. Since, service quality is an important factor in customer satisfaction, the study aims to assess the current service quality level which is being perceived by air passengers and theirsatisfaction levels for Airport Facilities at Bandaranaike International Airport (BIA), Katunayake comparing other Airports in other geographical regions (Indian Subcontinent, East Asia & Asia Pacific, Middle East and Europe). The main objective of the study was to understand importance of customer expectations and level of satisfaction perceived by passengers concerning the facilities, sendees and service quality of BIA, Katunayake. For data collection, an online questionnaire (created based on Google® forms) was provided and the population of the study was comprised of those who have experienced the services offered by BIA, specifically frequent air travelers of national origin. The questionnaire was developed using the SKYTRAX questionnaire as a benchmark. The questionnaire was distributed online to the target population who have travelled using BIA during last three years of time. The Likert survey was the selected questionnaire type as this enabled the respondents to answer the survey easily based on their evaluation levels. A total of 147 completed questionnaires were selected out of 163 due to incompleteness ofsome answers. Results shows that, responders (almost 50%) who have travelled within last three yearsthrough more than 05 airports in more geographical areas have less satisfaction level for most of questions than other responders who have visited five or less than five airports. Further responders (almost 20%) who have travelled through many airports (more than 10 airports within last three years) in more than two geographical areas have neutral or dissatisfied responses for most of questions than other responders who have visited ten or less than ten airports those were in one or two geographical areas. This indicates that service quality at BIA for some areas does not match the satisfaction level ofpassengers who have experienced many airports in several geographical areas. Moreover the study also concludes that the satisfaction level of passengers on service quality was significantly different based on number of airports which passengers have visited and geographical areas where those airports are located, especially passengers who have travelled only in Indian subcontinent had more satisfied responses on BIA comparing others. There were no significant difference in observations on satisfaction levels based on passenger’s gender, age group and reasons for travel, since 90% of passengers had travelled on business / employment purposes. In conclusion, the study suggests that policy makers as well as airport management need to comprehensive survey on passenger’s satisfaction level on their services offered and take workable measures to improve upon airport sendee quality

Functional Characteristics of Aldehyde Dehydrogenase and Its Involvement in Aromatic Volatile Biosynthesis in Postharvest Banana Ripening

Butanol vapor feeding to ripe banana pulp slices produced abundant butyl butanoate, indicating that a portion of butanol molecules was converted to butanoate/butanoyl-CoA via butanal, and further biosynthesized to ester. A similar phenomenon was observed when feeding propanol and pentanol, but was less pronounced when feeding hexanol, 2-methylpropanol and 3-methylbutanol. Enzymes which catalyze the cascade reactions, such as alcohol dehydrogenase (ADH), acetyl-CoA synthetase, and alcohol acetyl transferase, have been well documented. Aldehyde dehydrogenase (ALDH), which is presumed to play a key role in the pathway to convert aldehydes to carboxylic acids, has not been reported yet. The conversion is an oxygen-independent metabolic pathway and is enzyme-catalyzed with nicotinamide adenine dinucleotide (NAD+) as the cofactor. Crude ALDH was extracted from ripe banana pulps, and the interference from ADH was removed by two procedures: (1) washing off elutable proteins which contain 95% of ADH, but only about 40% of ALDH activity, with the remaining ALDH extracted from the pellet residues at the crude ALDH extraction stage; (2) adding an ADH inhibitor in the reaction mixture. The optimum pH of the ALDH was 8.8, and optimum phosphate buffer concentration was higher than 100 mM. High affinity of the enzyme was a straight chain of lower aldehydes except ethanal, while poor affinity was branched chain aldehydes