Antibacterial activity of bioemulsifiers/biosurfactants produced by Levilactobacillus brevisS4 and Lactiplantibacillus plantarumS5 and their utilization to enhance the stability of cold emulsions of milk chocolate drinks

Chocolate milk drink, one of the most popular and widely consumed milk products among the population, independent of their age, has as its main challenge the problem of its physical instability. The aim of this study was to assess the stabilizing effect of bioemulsifiers/biosurfactants (BE/BS) from two lactobacilli strains in a cold chocolate milk drink. The strains Levilactobacillus brevis S4 and Lactiplantibacillus plantarum S5 isolated from pendidam were screened for their ability to produce BE/BS. The produced BE/BS were characterized, their antimicrobial activities were assessed, and their ability to stabilize cold chocolate milk drinks was determined. The results obtained showed BE/BS yields of 3.48 and 4.37 g/L from L. brevis S4 and L. plantarum S5, respectively. These BE/BS showed emulsifying and surface activities that remained stable after treatment at different temperatures, pH, and salinity. The emulsions formed using BE/BS were stable for 72 h at room temperature (25 ± 1°C). The BE/BS exhibited antimicrobial activity against Staphylococcus aureus S1 and Escherichia coli E1. When applied to cold chocolate milk drinks at 0.2% (w/v), the BE/BS from L. brevis S4 and L. plantarum S5 showed interesting solubility indexes and water absorption capacities, which led to the successful stabilization of the drinks. The results of this study demonstrate the stabilizer potential of BE/BS from L. brevis S4 and L. plantarum S5 and suggest their use in the dairy and food industries.

Micronutrients and in vivo antioxidant properties of powder fractions and ethanolic extract of Dichrostachys glomerata Forssk. fruits

Dichrostachys glomerata powders were processed by sieve fractionation and ethanolic extraction followed by freeze-drying. The micronutrient contents and the in vivo antioxidant properties of powder fractions in rats' high-fat diet-induced oxidation model were determined. Sieved fractionation was achieved by finely grinding the Dichrostachys fruits and fractionating on a sieve column to retain particle of sizes <180, 180-212, 212-315, and ≥315 µm. Unsieved powder and lyophilized ethanolic extract were used as control. All the powders were examined for the minerals, total carotenoids, and vitamins contents. For in vivo antioxidant properties assessment, the individual powder was dissolved in water and administered to rats at the dose of 250 mg/kg body weight. Oxidation was induced by treating the rat with high-fat diet, and the measured parameters were malondialdehyde, superoxide dismutase, and catalase activities. The results showed a significant influence (p < .05) of particle size on the micronutrient contents and in vivo antioxidant properties. The smaller the particle size of the powder fractions, the higher the minerals, vitamins, total carotenoids contents, and antioxidant properties. Comparatively, the ethanolic powder had the highest carotenoids content, while the powders of particle size <180 µm and 180-212 µm had the highest minerals and vitamin contents. The highest antioxidant properties were characterized by high superoxide dismutase, catalase activities, and low malondialdehyde production. The grinding of Dichrostachys fruit followed by controlled differential sieving process may compete with ethanol extraction for an efficient concentration of bioactive compounds and micronutrients except carotenoids.

Hypolipidemic and anti-atherogenic effect of aqueous extract leaves of Ficus glumosa (Moraceae) in rats

Leaves of Ficus glumosa are used in northern Cameroon and southern Chad for the treatment of cardiovascular diseases, as food and as a stimulant for milk production in both women and animals. Atherosclerosis is a disease in which frequency increases with age. The first lesions appear at the young subject during adolescence. Atherosclerosis lesions appear very precociously and worsen with age. They interest the levels chronologically aortic, coronary then carotid. Age is a risk factor in that it reflects the exposure time of individual to the other risk factors. The frequency of the atherosclerosis increases with age because of the aging of the cells. This study was undertaken to evaluate the hypolipidemic and anti-atherosclerotic properties of aqueous extract of the leaves of F. glumosa in rats with hypercholesterolemia (HC). 60 male rats were fed for 4 weeks with a high-cholesterol diet (1%) and 3 doses (225, 300 and 375 mg/kg) of extract of F. glumosa were used in these experiments. The experiments were conducted under the same conditions with atorvastatin (1 mg/kg), as pharmacological reference substance. The effects of F. glumosa on weight gain, water and food consumption, levels of serum lipids and lipoprotein lipid oxidation and stress markers in the blood and liver were examined. The administration of F. glumosa extract prevented significant (P<0.05) elevation in TC, LDL-c, VLDL-c, hepatic and aortic TG and TC. The atherogenic, triglyceride, and lipid peroxidation (TBARS) indexes were also decreased in the rats treated with the extract. F. glumosa favored the performance of fecal cholesterol. It also significantly inhibited the changes and the formation of aortic atherosclerotic plaques. These results revealed the hypolipidemic and antiatherosclerotic effects of F. glumosa extract and support the traditional use of the extract of this plant in the treatment of hypertension and diabetes.

Evaluation of antinociceptive effects of Crassocephalum bauchiense Hutch (Asteraceae) leaf extract in rodents

ETHNOPHARMACOLOGICAL RELEVANCE

The leaves of Crassocephalum bauchiense have long been used in traditional Cameroonian medicine for the treatment of epilepsy, pain, inflammatory disorders, arthritis and intestinal pain.

AIM OF THE STUDY

In this study, we attempted to identify the possible antinociceptive action of the aqueous extract and the alkaloid fraction prepared from the leaves of Crassocephalum baucheiense.

MATERIALS AND METHODS

Using acetic acid induced abdominal constrictions, formalin-, capsaisin- and glutamate-induced nociception, and hot plate assay procedures, the antinociceptive effects of the aqueous extract and the alkaloid fraction was assessed after oral administration in mice. Morphine sulfate was used as reference analgesic agent. Mice were submitted to the rota-rod task and open-field test in order to assess any non-specific muscle-relaxant or sedative effects of the extracts of Crassocephalum bauchiense. Male and female Swiss mice were used to assess acute toxicity of these extracts.

RESULTS

The aqueous extract and the alkaloid fraction of Crassocephalum bauchiense produced a significant antinociceptive effects in the acetic acid, formalin, glutamate, capsaicin and hot plate tests. These antinociceptive effects of Crassocephalum bauchiense were significantly attenuated by pretreatment with naloxone. The extracts of Crassocephalum bauchiense did not alter the locomotion of animals in the open-field or rotarod tests, which suggest a lack of a central depressant effect. The animals did not exhibit any acute toxicity to the aqueous extract and the alkaloid fraction, so it was not possible to calculate the LD(50).

CONCLUSION

The results confirm the popular use of Crassocephalum bauchiense as an antinociceptive, and contribute to the pharmacological knowledge of this species because it was shown that the aqueous extract and the alkaloid fraction of Crassocephalum bauchiense produced dose related antinociception in models of chemical and thermal nociception through mechanisms that involve an interaction with opioidergic pathway.

Physicochemical and thermal properties of taro (Colocasia esculenta sp) powders as affected by state of maturity and drying method

The study was aimed at determining the effect of harvesting time and drying method on the thermal and physicochemical properties of taro powder, Sosso ecotype. A 5 × 2 factorial experiment with 5 harvesting times (6, 7, 8, 9 and 10 months after planting) and 2 drying methods (sun and electric oven drying) was used for this purpose. The variance component analysis revealed harvesting time as the most important factor affecting all the variables measured. In particular the proteins and available sugar contents of the powders increased significantly with increase in harvesting time. The same was true of the gelling property and water absorption capacity of the powders. It was equally observed that the temperatures (start, peak and end) and enthalpy of gelatinization of the powders increased with harvesting time. It is concluded that harvesting sosso-taro at full maturity (10 months after planting) and sun-drying produces food powders with excellent gelling properties among others.