Two-dimensional PCA highlights the differentiated antitumor and antimicrobial activity of methanolic and aqueous extracts of Laurus nobilis L. from different origins

Infusions of Herbal Blends as Promising Sources of Phenolic Compounds and Bioactive Properties

Several plants have been used for medicinal applications and have been traditionally consumed as decoctions and infusions. Although some herbs are used alone as a beverage, they are often blended in mixtures to maximize their effects. Herein, the nutritional characterization of six infusions from herbal blends was evaluated using the official methods of analysis (AOAC international). A further characterization of the individual phenolic profile was also performed by HPLC-DAD/ESI-MSn, and finally bioactive potential was determined by evaluating the antioxidant, cytotoxic, anti-inflammatory, and antimicrobial activities of each blend. The wide variety of plants in each sample led to variability in the results for all analyzed parameters. However, blends containing 15% Laurus nobilis L. and 15% Juglan regia L. in their composition showed higher sugar content and energy contribution; higher concentration of phenolic compounds (phenolic acids and flavonoids); greater antioxidant, cytotoxic, and anti-inflammatory capacity; and also better antimicrobial effects against all the tested bacterial and fungal strains. Further studies will be necessary to evaluate the real synergistic effects that these two species show in the presence of other plants, and to evaluate their potential for application in various food, pharmaceutical, and nutraceutical products as infusion preparations.

Phytochemical Content and In Vitro Antimycelial Efficacy of Colocasia esculenta (L), Manihot esculenta (Crantz) and Dioscorea rotundata (Poir) Leaf Extracts on Aspergillus niger and Botryodiplodia theobromae

TheIn Vitroefficacy of aqueous leaf extracts of common edible root crops (Colocasiaesculenta,ManihotesculentaandDioscorearotundata) were investigated againstAspergillusnigerandBotryodiplodiatheobromae. The fungi were isolated from rotten tubers of yam using antibiotic-amended potatoes dextrose agar. Graded aqueous leaf extract concentrations (25 g/L, 50 g/L and 75 g/L) of each plant were applied against each test fungi on PDA plates and their mycelial growth inhibition activities were monitored for 144 hrs. Camazeb (5 – 10 g/L), a fungicide, was used as positive control agent. The phytochemical constituents of each extracts were also analyzed using standard techniques. The patterns of antifungal activities of the extracts were concentration and pathogen dependent. The most effective mean mycelial growth inhibitions were found withD.esculentaandC.esculentaagainstB.theobromae(61.9 – 80.9 %) andA.niger(63.8 – 82.8 %), respectively. Though,M.esculentaleaf extracts generally demonstrated the least antifungal activities against both pathogens, their activities were significant at 75 g/L. The antifungal potency of bothD.esculentaandC.esculentawere comparable to Camabez (chemical fungicide), which demonstrated 100 % inhibition at both 5 and 10 g/L concentrations. Higher concentrations of saponins (5.64 - 6.71 mg/100g), tannins (4.42 – 7.23 mg/100g) and flavonoids (3.64 – 5.25 mg/100g) were detected in the extracts, and could probably be linked to the observed antifungal activities. Findings from this study showed thatD.esculenta,C.esculentaandM.esculentaposses bioactive molecules that could be exploited in the bio-control of phyto-pathogens of tubers crops, which are the main staple food in most tropical countries.