Journal of Natural Products Discovery

IN VITRO EVALUATION OF THE ANTIMICROBIAL, TOXIC, ANTI-ARTHRITIC AND THROMBOLYTIC PROPERTIES OF DIFFERENT PARTS OF PLANT ORCHID RHYNCHOSTYLIS RETUSA (L.) BLUME.

Thu, 27 Jun 2024 00:00:00 +0000

Background: Infection due to microbes, trauma, cancer, arthritis and thrombosis are the most common problems worldwide. Traditionally, a large number of herbal extracts are used for the treatment of those disorders.

Aim: Ethanolic extracts from leaves, roots and stems of Rhynchostylis retusa (L.) Blume were phytochemically characterised and then tested for their antibacterial, toxicity, anti-arthritic, and thrombolytic properties in-vitro.

Methods and Results: Disk diffusion inhibition tests with a panel of fourteen different microorganisms was used as the antimicrobial assays. Antimicrobial activity of the stem extract found to be higher (10-11 mm, 400 µg/disk) than that of root extract whereas leaf showed no activity with ciprofloxacin (43-46 mm, 5 µg/disc) serving as reference standard. Toxicity of the plant extracts in terms of their LC50 values against the brine shrimp (A. salina) was assessed. The toxic potential of leaf extract was 6.7 μg/ml, which is higher than that of stem and root extract (c.a. 8.5 μg/ml). Thrombolytic properties were tested in vitro using streptokinase as reference (%Clot lysis after 1.5h & 24h was 76.15±1.94 & 92.59±2.35, 30000iu). The leaf extract exhibited higher activity. Leaf extract (1000 ppm) lysed of 33.08±1.24% of the clot and 60.47±2.33 after 1.5 h and 24 h of incubation, respectively. Anti-arthritic effects measured as albumin denaturation using diclofenac sodium as reference (IC50=60.25 ppm) revealed the stem extract as more active.

Conclusion: our research will help to provide evidence for some of the traditional uses of this medicinal plant.

Soxhlet extraction cycle-dependent diversity in phenolic profile and antioxidant potency of red cabbage (Brassica oleracea var. capitata F. rubra)

Fri, 28 Jun 2024 00:00:00 +0000

Introduction: The Brassicaceae vegetables are a rich source of secondary metabolites that exhibit several health benefits and protection against numerous degenerative diseases.

Objectives: The current study was performed to investigate the effect of Soxhlet extraction cycles on the phenolic profile of red cabbage (Brassica oleracea var. capitata F. rubra) and its biological activities.

Materials and Methods: The red cabbage sample was harvested from the research fields of Ayub Agricultural Research Institute Faisalabad, Pakistan. The ethanol extracts were prepared using 1-, 2-, 4-, and 8-cycles Soxhlet extraction technique. The antioxidant potential of red cabbage extracts was estimated by evaluation of total phenolic contents (TPC), total flavonoid contents (TFC), DPPH radical scavenging capacity and reducing power. The identification and quantification of polyphenols were carried out by RP-HPLC. The antibacterial activity of red cabbage extracts was determined against Escherichia coli and Staphylococcus aureus and the antiproliferative activity was carried out by MTT mitochondrial viability assay against the human A549 cancer cell line.

Results: Gallic acid, p-hydroxyl benzoic acid, chlorogenic acid, and p-coumaric acid were the major phenolic acids, whereas catechin and quercetin were the major flavonoids detected in the red cabbage extracts. The extraction cycles were found to have significant (p ≤ 0.05) effects on the phenolic profile of the red cabbage extracts. TPC of extracts ranged from 5.22-11.72 mg/g dry matter, measured as gallic acid equivalent, while the TFC ranged from 1.64-5.19 mg/g dry matter; measured as catechin equivalent. The 4-cycles extract of red cabbage exhibited the maximum TPC, TFC, and DPPH free-radical scavenging and reducing activity.

Conclusion: The study concluded that the Soxhlet extraction cycles could exert a considerable effect on the yield and polyphenol composition of red cabbage extracts as well as their antioxidant potential. Antibacterial and antiproliferative activities were observed by all the extracts of red cabbage.

APOPTOTIC ACTIVITY OF BOSWELLIA CARTERII EXTRACT ON HUMAN NEUTROPHILS.

Martín Dadé, Jose Prieto-Garcia, Flavio Fancini, Guillermo Raúl Schinella — Wed, 31 Jan 2024 00:00:00 +0000

Neutrophil activation is required for the initiation of the defence mechanisms which include phagocytosis. Paradoxically, neutrophils also represent one of the main mediators of tissue injury in various human diseases. The resolution of inflammation requires getting rid of excess inflammatory cells through natural cell death and phagocyte clearance. Frankincense, an oleogum resin of different species of the genus Boswellia (Burseraceae), has long been used in eastern countries' traditional medicine to alleviate pain and inflammation. Although it was demonstrated that boswellic acids are potent activators of polymorphonuclear cells, little is known about the effects of the total extract on the human phagocytes’ apoptosis.

We here undertake a characterization of the Boswellia carteri resin extract (BCE) effects on human neutrophils activity and viability in vitro. Oxidative burst after stimulation with BCE was evaluated by reduction of nitroblue tetrazolium (NBT) colorimetric method for superoxide anion radical in the the presence of different compounds (N-ethyl maleimide, diltiazem, chelerythrine and wortmannin). Neutrophils viability was assessed by MTT. Flow analyses were performed with propidium iodide (PI) and annexin V-FITC.

Our results show that BCE induces the release reactive species of oxygen in human neutrophils in a dose dependent manner. The superoxide anion radical is principally produced via NADPH oxidase since inhibitors of the enzyme may prevent it. Ca⁺² depletion reduce the magnitude of activation and PKC and PI3-K are also apparently involved in the process. The BCE has also cytotoxic activity revealed by the MTT assay. This effect seems to be produced by an apoptotic process as shown by the exclusion of the dye propidium iodide and the annexin V-FITC binding.

The capacity of the Boswellia carterii extract to accelerate the cellular death by an apoptotic process suggest that either the extract or its active compounds could have applications for the resolution of some inflammatory conditions.