Chemical composition and biological activities of essential oil and extracts from Ocimum sanctum

Ocimum Species: A Review on Chemical Constituents and Antibacterial Activity

Infection by bacteria is one of the main problems in health. The use of commercial antibiotics is still one of the treatments to overcome these problems. However, high levels of consumption lead to antibiotic resistance. Several types of antibiotics have been reported to experience resistance. One solution that can be given is the use of natural antibacterial products. There have been many studies reporting the potential antibacterial activity of the Ocimum plant. Ocimum is known to be one of the medicinal plants that have been used traditionally by local people. This plant contains components of secondary metabolites such as phenolics, flavonoids, steroids, terpenoids, and alkaloids. Therefore, in this paper, we will discuss five types of Ocimum species, namely O. americanum, O. basilicum, O. gratissimum, O. campechianum, and O. sanctum. The five species are known to contain many chemical constituents and have good antibacterial activity against several pathogenic bacteria.

Inter-Varietal Variation in Phenolic Profile, Sugar Contents, Antioxidant, Anti-Proliferative and Antibacterial Activities of Selected Brassica Species

The main objective of this research work was to evaluate the variation in nutritional profile, antioxidant, anti-proliferative and antibacterial activities of selected species of Brassica. Five locally grown Brassica species (cauliflower, broccoli, red cabbage, white cabbage and Chinese cabbage) were collected from Ayub Agriculture Research Institute (AARI), Faisalabad, Pakistan. Polyphenolic rich extracts of these Brassicaceae species were prepared by Soxhlet extraction technique using ethanol. Phenolic acids, flavonoids and sugar contents of the investigated species were determined and quantified by RP-HPLC. Antioxidant activity was carried out by measurement of total phenolic contents (TPC), total flavonoid contents (TFC), reducing potential and 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity. Anti-proliferative activity of all the extracts was determined by MTT assay on lung cancer cell line A549. Antibacterial activity was tested against the two bacterial strains, i.e., Bacillus cereus (B. cereus) and Escherichia coli (E. coli). HPLC analysis revealed the presence of gallic acid, p-coumaric acid, chlorogenic acid and benzoic acid as the major phenolic acids, whereas catechine was the major flavonoid in most of the extracts. The TPC ranged from 9.7 to 32.8 mg/g of dry plant material, measured GAE and TFC ranged from 7.7 to 23.7 mg/g of dry plant material, measured as CE. Higher TPC and TFC were found in red cabbage extract followed by cauliflower, broccoli, white cabbage and Chinese cabbage. Red cabbage extract also showed higher DPPH radical scavenging activity (IC50 = 2.3 µg/mL) followed by cauliflower, broccoli, white cabbage and Chinese cabbage. Maltodextrose was the major sugar followed by fructose in all species of Brassica. Promising anti-proliferative and antibacterial activities were also recorded by the selected Brassica extracts.

Fagonia arabica L.: A review of its phytochemistry, pharmacology and traditional uses

BACKGROUND

Fagonia arabica, belongs to family Zygophyllaceae, is a medicinal plant, widely distributed in the desert areas of the world including Saudi Arabia, Pakistan, India and South Africa. The present review aims to explore the published information on the traditional uses, ethnobotanical knowledge, phytochemistry and various biological activities like antioxidant, antimicrobial, thrombolytic activities and anticoagulant effects of Fagonia arabica with critical analysis on the gaps and future perspectives.

METHOD

A literature survey was performed by searching the digital libraries and the scientific databases including Scopus, Google Scholar, SciFinder, ACS, Web of Science and published books.

RESULTS

Fagonia arabica plant has been reported to have a wide range of traditional uses in sore mouth, smallpox, hematological, neurological, endocrinological, inflammatory, cooling agent in stomatitis, vertigo and endothermic reaction in the body. Several bioactive constituents including glycosides, flavonoids, terpenoids, saponins, alkaloids and trace elements were recorded from Fagonia arabica plant. The isolation and identification of two flavonoid glycosides (kaempferol-7-O-rhamnoside and acacetin-7-O-rhamnoside) were also reported. Fagonia arabica has been studied for its wide range of biological activities, which include antioxidant, antimicrobial, cardioprotective and anticoagulant.

CONCLUSION

It is apparent from the literature that Fagonia arabica plant possesses a wide range of medicinal and pharmacological uses and has been studied for its various pharmacological activities and medicinal applications. Critical analysis reveals that the plant has the huge potential for pharmaceutical and pharmacological applications.

The interactive effect of aromatic amino acid composition on the accumulation of phenolic compounds and the expression of biosynthesis-related genes in Ocimum basilicum

Sweet basil (Ocimum basilicum L.), a well-known medicinal and aromatic herb, rich in essential oils and antioxidants (contributed by phenolics), is widely used in traditional medicine. The biosynthesis of phytochemicals occurs via different biochemical pathways, and the expression of selected genes encoding enzymes involved in the formation of phenolic compounds is regulated in response to environmental factors. The synthesis of the compounds is closely interrelated: usually, the products formed in the first reaction steps are used as substrates for the next reactions. The current study attempted a comprehensive overview of the effect of aromatic amino acid composition (AAAs) in Ocimum basilicum in respect to the expression of genes related to the biosynthesis of phenolic compound and their content. The transcript expression levels of EOMT, PAL, CVOMT, HPPR, C4L, EGS, and FLS increased depending on the AAAs concentration compared to the control plants. The highest mRNA accumulation was obtained in EOMT, FLS, and HPPR in the leaves of sweet basil. The expression of the TAT gene in the leaves significantly reduced in response to all AAAs applications compared to untreated groups and it had the lowest transcript accumulation. Eleven individual phenolic compounds were determined in the basil leaves, and the contents of chicoric acid, methyl chavicol, caffeic acid, and vanillic acid increased depending on administered concentration to control (p < 0.05). Additionally, AAAs lead to an incremental change in the amount of chlorogenic acid at 50 and 100 mg kg^-1 compared to control plants (p < 0.05). Rutin and rosmarinic acid were detected as the main phenolic compounds in all experimental groups of sweet basil in terms of quantity. However, their amount significantly decreased as compared to control plants based on the increase in AAAs concentrations (p < 0.05). Also, the accumulation of cinnamic acid, eugenol, and quercetin did not significantly change in the leaves of AAAs treated plants compared to control (p < 0.05). When AAAs was applied, total flavonoid content increased in all treatments compared to the control plants, but total phenolic content did not change significantly (p < 0.05). To the best of our knowledge, our work is the first detailed work to evaluate in detail the impact of AAAs on individual phenolic compounds at the phytochemistry and transcriptional levels in the O. basilicum plant. For a detailed understanding of the whole mechanism of phenolic compound regulation, further research is required to fill in some gaps and to provide further clarification.

Trigonella foenum-graecum Seeds Oil Attenuated Inflammation and Angiogenesis in vivo through Down-Regulation of TNF-α

INTRODUCTION

Inflammation is a vital reaction of the natural immune system that protects against encroaching agents. However, uncontrolled inflammation can lead to complications. Trigonella foenumgraecum is traditionally used as an anti-inflammatory herb.

OBJECTIVES

The current study was conducted to explore the antioxidant, anti-inflammatory, and antiangiogenic potentials of Trigonella foenum-graecum seeds oil.

METHODS

Oil was extracted from seeds of Trigonella foenum-graecum by cold press method and labelled as TgSO. Phytochemical (GC-MS, Folin-Ciocalteu method) and metal analyses were conducted to evaluate the metalo-chemical profile of TgSO. In vitro antioxidant assays (2,2-diphenyl-1-picrylhydrazyl, 2,2'-azino-bis-3- ethylbenzothiazoline-6-sulfonic acid and ferric reducing antioxidant power) were performed to assess its antioxidant potential. In vitro antimicrobial activity was evaluated using agar disc diffusion method and the safety profile of TgSO was assessed in acute toxicological studies following OECD 425 guidelines. In vivo antiinflammatory activities of TgSO were assessed in carrageenan, serotonin, histamine, formalin, and cotton pelletinduced oedema models. Serum TNF-α, Superoxide Dismutase (SOD) and, Catalases (CAT) levels were assessed by ELISA kits. In vivo antiangiogenic activity of TgSO was screened in chick Chorioallantoic Membrane (CAM) assay. Histopathological studies using excised paws were conducted to observe the effects of TgSO treatment at the tissue level. In silico docking studies were conducted to screen the binding potentials of identified compounds with TNF-α.

RESULTS

Extraction by cold press method yielded 16% of TgSO. Phytochemical analysis of TgSO through GCMS showed the presence of eugenol, dihydrocoumairn, heptadecanoic acid, tri- and tetradecanoic acid, and hexadecanoic acid, respectively. Total phenolic contents of TgSO were found to be 0.30±0.01mg/g gallic acid equivalent in Folin-Ciocalteu method. Metal analysis indicated the presence of different metals in TgSO. Findings of antioxidant models showed the moderate antioxidant potential of TgSO. Findings of antimicrobial assays showed that TgSO was active against bacterial (S. aureus, S. epidermidis) and fungal (C. albicans, and A. niger) strains. In vivo toxicity study data showed that TgSO was safe up to the dose of 5000 mg/kg. Data of oedema models showed a significant (p<0.05) reduction in oedema development in TgSO treated animals in both acute and chronic models. Histopathological evaluations of paws showed minimum tissue infiltration with inflammatory cells in TgSO-treated animals. Treatment with TgSO also significantly (p<0.05) down-regulated TNF-α in serum while levels of SOD and CAT were up-regulated. Findings of the CAM assay revealed the antiangiogenic activity of TgSO. Findings of in silico docking studies showed that identified phytoconstituents can bind with culprit cytokine (TNF-α).

CONCLUSION

Data obtained from the current study conclude that TgSO has antioxidant, anti-inflammatory, and antiangiogenic effects that validate its traditional uses. Synergistic actions of different phytoconstituents are proposed to be responsible for the observed effects.

Chemical Composition and Bioactivities of Essential Oil from Leaves of Syzygium cumini (L.) Skeels Native to Punjab, Pakistan

Herbal medicines are widely used for the treatment of different types of diseases like skin and throat infections and other diseases in developing countries. Syzygium cumini (L.) Skeels fruit, leaves and bark were used for the remedies of different diseases anciently. The aim of the present study was to evaluate the chemical profile of Syzygium cumini leaves essential oil (EO) from Punjab, Pakistan. The essential oil was isolated using hydrodistillation technique and analyzed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC/MS). Free radical scavenging capacity and antioxidant activity were assessed by using DPPH radical scavenging ability, inhibition of linoleic acid peroxidation, bleaching of β-carotene in linoleic acid system and reducing power assays. Antimicrobial potential was assessed by disc diffusion assay and measurement of minimum inhibitory concentration (MIC) using resazurin microtiter-plate assay. The anti-heme biocrystallization activity of EO was also assessed. The major components (>3%) found in Syzygium cumini leaves EO were β-farnesene (3.42 %), caryophyllenol (3.46 %), terpinen-4-ol (3.61 %), β-myrcene (3.90 %), γ-cadinene (4.09 %), fenchol (4.22 %), cis-β-ocimene (4.40 %) and 5-methyl-1,3,6-heptatriene (4.90 %). Excellent antioxidant, antimicrobial and weak antimalarial potential was observed. It can be concluded that Syzygium cumini leaves EO has potential application for food and pharmaceutical industries.

Effect of Substrates on Catalytic Activity of Biogenic Palladium Nanoparticles in C-C Cross-Coupling Reactions

This work describes a practical methodology for C-C bond formation reactions with the aid of biogenic palladium nanoparticles, which are synthesized by using phytochemicals extracted from two common plant species. Comparative studies have been done on the activity of two plant species (Ocimum sanctum and Aloe vera) in generation of palladium nanoparticles via ex situ and in situ methods. The structural and morphological characteristics of the nanoparticles are examined by UV/visible spectroscopy, powder X-ray diffraction, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, and transmission electron microscopy analyses. We have observed a significant influence of the substrates on the catalytic activity of the palladium nanoparticles in Sonogashira and Suzuki cross-coupling reactions.