Geographic variation in phytochemical constituents and allelopathic potential of Pinus halepensis barks

Aqueous extracts (10, 20, 30 and 40 g/L) of Pinus halepensis barks, collected from Bizerte (B), Tabarka (T), Seliana (S) and Oueslatia (O) to elucidate the influence of ecological sites on allelopathic potential. Aqueous barks extracts from (S) and (O) have revealed a higher rate of phenolic acids than those from (T) and (B), respectively 13.23, 13.8, 11.63 and 10.37 mg/mL. Alep pin barks were analyzed using HPLC/UV for the identification and quantification of the phenolic compounds, among which in particular the catechin acetate, the gallic acid, the rutine hydrate, luteolin 7 glucoside and the cinnamic acid. In fact, the aqueous extract of barks from (S) revealed a highest level, respectively 2.61, 1.74, 1.61, 1.36, and 1.21 mg/mL. The Pinus halepensis barks was analyzed by GC and GC-MS. As a result, 29 compounds were identified representing 89% made up basically by β-caryophyllene, α-humulene. As for allelopathic activity, aqueous extracts of barks significantly delayed germination, reduced its rate and affected the seedling growth mainly the (S) and (O) extracts. The root growth of the two targets has shown a high sensibility compared to the shoot lengths. Pot cultures were conducted by the incorporation of barks powder (50 and 100 g/kg) or the irrigation with their aqueous extracts at 20 and 40 g/L. Pinus halepensis barks and its extracts have shown a high herbicide potent, particularly the one collected from (S) and (O), may be favorably used for incorporating in agricultural systems for sustainable weed managemen

Chemical composition, nutritional value, and biological evaluation of Tunisian okra pods (Abelmoschus esculentus L. moench)

The aim of this work was to perform an unprecedented in-depth study on the bioactive phytochemicals of Abelmoschus esculentus L. Moench Tunisian landrace (Marsaouia). For this purpose, its nutritional, aroma volatile, and phenolic profiles were characterized, and sundry biological activities were assessed in vitro. The approximate composition revealed that total dietary fiber as the most abundant macronutrient, mainly insoluble dietary fiber, followed by total carbohydrates and proteins. In addition, okra pods were rich in K, Ca, Mg, organic acids, tocopherols, and chlorophylls. Gas Chromatography-Electron Impact Mass Spectrometry (GC-EIMS) analysis showed that oxygenated monoterpenes, sesquiterpene hydrocarbons, and phenylpropanoids were the predominant essential volatile components in A. esculentus pods. A total of eight flavonols were detected by High-Performance Liquid Chromatography coupled to a DAD detector and mass spectrometry by electrospray ionization (HPLC-DAD-MS/ESI); with quercetin-3-O-glucoside being the majority phenolic component, followed by quercetin-O-pentosyl-hexoside and quercetin-dihexoside. This pioneering study, evidences that Tunisian okra display promising antioxidant and cytotoxic actions, in addition to relevant inhibitory effects against α-amylase and α-glucosidase enzymes, and interesting analgesic activity

Allelopathic potential of Pinus halepensis needles

The green and mature senescent needles of Pinus halepensis from the Tunisian pine forests of Bizerte, Tabarka, Seliana and Oueslatia were evaluated based on their phytochemicals contents for allelopathic potential on seed germination and seedling growth of radish (Raphanus sativus L.) and wheat (Triticum aestivum L.). Aqueous extracts of green needles of Seliana and Oueslatia regions, significantly delayed the germination and adversely affected the seedlings growth. In Pot culture studies, mature and green needles powder or soil treatment with needles aqueous extracts were also very inhibitory to seedling growth. The phenolic acids compositions of green and mature needles were determined using HPLC. Analysis of the needles for their phytochemical content showed that the aqueous extracts of green needles contained higher amount of phenolic acids than in mature needles. The phenolics contents in the needles also varied with ecological sites. Needles from Seliana and Oueslatia regions had higher amount of phenolics than those from Tabarka and Bizerte regions. The aqueous extract of green needles from Seliana region had higher levels of gallic acid and 2, 4-D Pestanal, while, the mature needles from Seliana had higher level of cinnamic acid. The green and mature needle extracts were also analyzed for chemical components by GC and GC-MS and 47-compounds were identified, representing 89% of the total compounds, with beta-caryophyllene, a-pinene and myrcene being the predominant

Chemical characterization and nutritional quality investigations of healthy extra virgin olive oil flavored with chili pepper

The production of extra virgin olive oil (EVOO) flavored with diverse spices, herbs, fruits, and vegetables or natural aromas is believed to provide advantageous properties considering either the high nutritional value or biological activity in addition to the flavoring and industrial aspects. The biological activities including antioxidant and antimicrobial properties of Tunisian EVOO obtained from “Chemlali” variety and mixed with chili pepper were investigated. Molecular analyses, including the detection of twelve olive-infecting viruses and Pseudomonas savastanoi pv savastanoi, were performed to ensure that the samples were obtained from healthy olive trees and EVOO quality was not affected. Quality parameters like free acidity, peroxide number, oxidative stability, and specific absorption at K232 nm and K270 nm were also investigated and no significant variation was revealed. The content of minor compounds such as chlorophylls, carotenoids, and total phenols showed minor changes. However, the profiles of the volatile compounds showed remarkable differences, which appeared to be the main factor for the observed variability in consumer acceptance. The results showed for the first time high quantities of polyphenols and ortho-diphenols. Four colorimetric methods were used for the determination of the antioxidant activity, namely DPPH, ABTS, FRAP, and β-carotene test. Compared to the control, a higher level of antioxidant activity was observed for the flavored EVOO. Furthermore, significant results were obtained in the antimicrobial tests. The quality parameters of the mixture showed no alteration compared to the control. Finally, all the measurements and the chemical characterization gave a scientific basis for food technology innovation of new food products

Protective potential of Opuntia microdasys flower decoction on fructose-alloxan-induced diabetic rats on kidney and pancreas: chemical and immunohistochemical analyses

Diabetes is a serious condition that is linked to the development of oxidative stress causing among many other effects, kidney failure and pancreatic disorders. However, traditional plant-based remedies can be considered an alternative to diabetes healing. In this context, this study was oriented towards evaluating the protective effect of the flowers of Opuntia microdasys Lehm. collected in Tunisia at a biochemical and histological level on kidneys and pancreas of a type 2 diabetic rats. Renal and pancreatic toxicities were induced in diabetic male Wistar rats by fructose alloxan. Diabetic rats were treated with an extract obtained from flowers collected at post-flowering stage (OFP) (100 and 200 mg kg−1 bw) and metformin (100 mg kg−1 bw) for 28 days. Oral administration of OFP at 200 mg kg−1 bw showed significant reduction of the uric acid, urea, creatinine, amylase, lipase, and glycated hemoglobin (HbAlc). The levels of SOD, CAT, and GPx were increased, while protein carbonyls and lipid peroxidation TBARS levels were reduced in the kidney and pancreas. The altered kidney and pancreas histology were restored in rats treated with OFP. Thus, the present study demonstrated that OFP has antihyperglycemic activity in fructose-alloxan-induced diabetic rats