The present study was conducted to compare the antibacterial activity of oven‐dried and freeze‐dried Allium sativum along with its spray‐dried microencapsulated essential oil in the preservation of minced beef meat. Allium sativum extracts were tested against mesophilic aerobic microorganisms, coagulase‐positive staphylococci, Escherichia coli, Salmonella sp., and the sulfite‐reducing anaerobes. A difference between the chemical compositions of powders obtained by the conventional oven‐drying and freeze‐drying has been verified by HPLC‐MS2, freeze‐dried fresh garlic powder contains 74% of allicin, and 12% cysteine sulfoxides comparing to the oven‐drying garlic powder in which is detected two thiosulfinate isomers: allicin (67%) and allyl‐1‐propenyl thiosulfinate (21%). CIELAB color analysis was performed to assess the effect of drying temperature on powders. The microflora‐inhibiting effect of freeze‐dried fresh garlic and the spray‐dried microencapsulated essential oil at a concentration of 20% represents a promising way to be used in food systems such as meat and meat products preservation, at 4–8°C.
Plants have been seen to possess the potential to be excellent biological matrices to serve as a basis for investigating the presence of promising therapeutic agents for cancer treatment. Several successful anti-cancer medicines - or their analogues - nowadays in use are plant derived and many more are under clinical trials. Under current circumstances, the purpose of this work was to test aqueous and ethanolic extracts of five aromatic and medicinal plants from arid zones on some tumor cell lines. These plants, Cymbopogon schoenanthus (L.) Spreng , Crithmum maritimum (L.) Spreng , Hammada scoparia (Pomel) Iljin , Retama raetam (Forssk.) and Zizyphus lotus (L.) Desf., widely used in Tunisian ethnomedicine, were assessed for their phenolic compounds, antioxidants and anticancer activities in aqueous and ethanol extracts. Total polyphenols, flavonoid and tannin contents were determined colorimetrically and some of these molecules were identified using RP-HPLC. A significant difference on phenolic contents and composition were found among the investigated plants. Cymbopogon schoenanthus was the richest in phenolic compounds (approx. 72%) with quercetine-3-o-rhamnoside (approx. 33%) as main contributor. For all the tested plants, the highest antioxidant capacity was detected in the ethanolic extracts rather than in the aqueous ones. The highest antiproliferative potential was observed for the ethanolic extracts. Hammada scoparia, Retama raetam and Zizyphus lotus exhibited important antiproliferative effect that reached 67% at a 1% extract concentration. Taken together, the present study supports the potential development of chemotherapeutic agents from, at least, four of the five studied Tunisian ethnomedicinal plants.
Jujube (Ziziphus lotus L.) fruit has multiple functional properties and represents an interesting source of bioactive compounds. The purpose of this study was to improve the functionality and the sensory properties of sponge cake enriched with Z. lotus fruit. The polyphenols and flavonoids levels in the sponge cake and its antioxidant potential increased with the addition of 0–10 g of jujube powder/100 g of wheat flour. The crumb color parameters, L* and b*, decreased with the addition of jujube powder, whereas the a* value increased. In the texture analysis, addition of jujube powder resulted in an increase of the hardness and chewiness, but the springiness was reduced. The sensory evaluation showed that supplementation of jujube powder did not manifest any undesirable organoleptic response and showed satisfactory consumer acceptability. Overall, the addition at 5% jujube powder showed the finest sensory properties of the sponge cake.
Rosemary (Rosmarinus officinalis L.) is a popular herb in cooking, traditional healing, and aromatherapy. This study was conducted to evaluate the effects of meteorological conditions plant growth stage and genetic factors on the yield, quantitative and qualitative composition, on the antioxidant and antimicrobial activities of rosemary essential oil from two Tunisian locations (El Fahs and Matmata) during two successive years. The composition of the essential oils obtained by hydrodistilation from rosemary plants were carried out annually using GC and GC/MS. Results showed the the main constituents were camphor (18.2–28.1%), 1,8-cineole (6.4–18.0%), α-pinene (9.7–13.5%), borneol (4.4–9.5%), and camphene (5.1–8.7%). The principal component and heatmapper analyses showed group segregation of the two studied varities based on major essential oil compounds. Additionally, in vitro antimicrobial and antioxidant activities showed that rosemary essential oils had an important ability in scavenging DPPH, as well as a higher bactericidal effect. The seasonal variation, growth stage and genetic pools seemed to be a factors of significant variation of the composition, antimicrobial and the antioxidant activities of the rosemary essential oils. These finding would be taken to use the chemotaxonomy tools to develop a program for Rosmary protection conservation and identification based on essential oil composition.