Fungicidal activity of four essential oils fromPiper capense,Piper borbonenseandVetiveria zizanoidesgrowing in Comoros against fungi decay wood

Analytically Unsupervised Metabolomic Profile of the Premium Malgasy Pepper Voatsipérifery (Piper borbonense): Identification of Marker Components

The berries of Piper borbonense (Miq.) C. DC., a wild vine native to Madagascar, are prized for their distinctive aroma and flavor, considered superior to the ones of the domesticated peppers (P. nigrum L., P. longum L.). The scarcity of studies on P. borbonense, locally known as voatsipérifery, makes it difficult to secure the identity of its berries and complement its sensory analysis. This supports the need for a comprehensive phytochemical investigation utilizing complementary analytical techniques. Headspace gas chromatography highlighted differences in the "volatilome" of P. borbonense and P. nigrum, while an untargeted metabolomic analysis, based on the LC-MS2-based feature-based molecular networking tool, annotated different classes of compounds (monoterpenoids, sesquiterpenoids, monolignols, lignans, and piperamides). This analysis next guided the isolation of 40 fully characterized compounds, including two new natural products [the sesquiterpene lactone 4-hydroxyisogelehomanolide (29) and the hydroxycinnamate ester borbonensin (38)]. The phytochemical profile of voatsipérifery is remarkable for the presence of the nonvolatile monoterpene p-menth-5-en-1,2-diol (23), of sesquiterpene lactones, and of large amounts of sesamin (34), a marker trait that clearly distinguishes it from those of the cultivated peppers of commerce and was confirmed with a parallel investigation of P. nigrum. Overall, our study underlines the relevance of advanced metabolomic approaches to characterize the phytochemical profile of spices and identify specific marker compounds.

A Comprehensive Review of the Ethnobotanical Uses, Pharmacological, and Toxicological Profiles of Piper capense L.f. (Piperaceae)

Commonly known as wild pepper, Piper capense (P. capense) is a culinary herb mainly used as a secret in preparation of “Nkui” and “Nah poh” in Bayangam, West Cameroon. However, it also has many interesting pharmacological properties, which is why the people of sub-Saharan Africa so highly prize it for the treatment of multiple human pathologies. This study aimed to highlight the traditional uses, phytochemical composition, biological activities, and toxicological profile of the P. capense plant, to draw the attention of pharmaceutical companies to its enormous potential for the development of future phyto- or pharmaceutical products. Documentary research was meticulously carried out in the Web of Sciences, Scopus, Pubmed/Medline, and Google Scholar databases according to PRISMA 2020 guidelines. The results show that extracts and compounds isolated from Piper capense have interesting anticancer, antibacterial, antimalarial, hypoglycemic, anti-epileptic, and antidepressant activities. Methanolic extracts and essential oils from P. capense exhibit no harmful effects when directly applied to normal human hepatocytes, umbilical cord cells, intestinal cells, and keratinocyte cell lines. Additionally, methanolic extracts administered acutely or subchronically at low doses (≤250 mg/kg body weight) in Wistar rats also demonstrate no adverse effects. In conclusion, given its interesting activities, P. capense is a viable option for developing new antimalarial, anticancer, antibacterial, hypoglycemic, anti-epileptic, and antidepressant drugs. However, many avenues still need to be explored before translation into drugs.

Assessment of Contact Toxicity and Repellent Effects of Essential Oils from Piper Plants Piper yunnanense and Piper boehmeriifolium against Three Stored-Product Insects

Storage is a crucial part during grain production for the massive spoilage caused by stored product insects. Essential oils (EOs) of plant origin have been highly recommended to combating insects which are biodegradable and safe mode of action. Hence, to make the fullest use of natural resources, essential oils of different parts from Piper yunnanense (the whole part, PYW; fruits, PYF; leaves, PYL) and Piper boehmeriifolium (leaves, PBL) were extracted by steam distillation method in the present study. Gas chromatography-mass spectrometry (GC-MS) characterization revealed bicyclogermacrene (PYW), γ-muurolene (PYF), δ-cadinene (PYL) and methyl 4,7,10,13,16,19-docosahexaenoate (PBL) as the principal compound of each essential oil. Sesquiterpene hydrocarbons were also recognized as the richest class accounting for 56.3 %-94.9 % of the total oil. Three storage pests, Tribolium castaneum, Lasioderma serricorne and Liposceis bostrychophila, were exposed to different concentrations of EOs to determine their insecticidal effects. All tested samples performed modest contact toxicity in contrast to a bioactive ingredient pyrethrin, among which the most substantial effects were observed in PYF EOs against T. castaneum (35.84 μg/adult), PBL EOs against L. serricorne (15.76 μg/adult) and PYW EOs against L. bostrychophila (57.70 μg/cm2 ). In terms of repellency tests, essential oils of PYF at 78.63 nL/cm2 demonstrated to have a remarkable repellence against T. castaneum at 2h and 4h post-exposure. The investigations indicate diverse variations in the chemical profiles and insecticidal efficacies of P. yunnanense and P. boehmeriifolium EOs, providing more experimental evidence for the use of the Piper plants.

Simultaneous Hydrodistillation of Cedrus atlantica Manetti and Salvia rosmarinus Spenn: Optimization of Anti-Wood-Decay Fungal Activity Using Mixture Design Methodology

Chemical fungicides are often harmful to people and the environment because of their toxicity. The wood protection industry places a high priority on replacing them with natural products. Therefore, this investigation focused on developing a formulation of a binary combination of Salvia rosmarinus Spenn and Cedrus atlantica Manetti obtained by Simultaneous hydrodistillation to protect the wood from decay using a mixture design methodology. The chemical composition of essential oil was identified by gas chromatography coupled with mass spectrometry (GC/MS), and their anti-wood-decay fungal activity was assessed using the macrodilution method against four fungi responsible for wood decay: Coniophora puteana, Coriolus versicolor, Gloeophyllum trabeum, and Poria placenta. The results of GC/MS identified myrtenal as a new component appearing in all binary combinations. The optimum anti-wood-decay fungal activity was observed in a combination of 60% S. rosmarinus and 40% C. atlantica essential oils, providing an effective concentration for 50% of maximal effect (EC50) value of 9.91 ± 1.91 and 9.28 ± 1.55 μg/mL for C. puteana and C. versicolor, respectively. The highest anti-wood-decay fungal activity for G. trabeum and P. placenta was found in the combination of 55% of S. rosmarinus and 45% of C. atlantica essential oils, with EC50 values of 11.48 ± 3.73 and 22.619 ± 3.79 μg/mL, respectively. Combined simultaneous hydrodistillation improved the antifungal effect of these essential oils. These results could be used to improve antifungal activity and protect wood against wood-decay fungi.

Back to the Roots-An Overview of the Chemical Composition and Bioactivity of Selected Root-Essential Oils

Since ancient times, plant roots have been widely used in traditional medicine for treating various ailments and diseases due to their beneficial effects. A large number of studies have demonstrated that-besides their aromatic properties-their biological activity can often be attributed to volatile constituents. This review provides a comprehensive overview of investigations into the chemical composition of essential oils and volatile components obtained from selected aromatic roots, including Angelica archangelica, Armoracia rusticana, Carlina sp., Chrysopogon zizanioides, Coleus forskohlii, Inula helenium, Sassafras albidum, Saussurea costus, and Valeriana officinalis. Additionally, their most important associated biological impacts are reported, such as anticarcinogenic, antimicrobial, antioxidant, pesticidal, and other miscellaneous properties. Various literature and electronic databases-including PubMed, ScienceDirect, Springer, Scopus, Google Scholar, and Wiley-were screened and data was obtained accordingly. The results indicate the promising properties of root-essential oils and their potential as a source for natural biologically active products for flavor, pharmaceutical, agricultural, and fragrance industries. However, more research is required to further establish the mechanism of action mediating these bioactivities as well as essential oil standardization because the chemical composition often strongly varies depending on external factors.

Effects of orange essential oil on intestinal microflora in mice

BACKGROUND

The intestinal microbiota has a wide variety of functions in the host. A positive effect of plant extract on intestinal microbiota in animals has been reported. However, the effect of orange essential oil and its components limonene, linalool and citral on intestinal microflora in mice has seldom been reported. The effects of intragastric administration of orange essential oil and limonene, linalool and citral on intestinal microflora and biochemical indexes in mice were studied.

RESULTS

The effect of essential oil, linalool and citral on immune organ index (spleen and thymus index), IgM and IL-2 was not significant (P > 0.05). A significant increase (P < 0.05) of H⁺ K⁺ -ATPase activity, IgA, IgG, and IL-2 in the limonene group was observed when compared with the control group. Orange essential oil, limonene, linalool and citral could significantly reduce the content of short-chain fatty acids in the cecum and colon of mice. Principal coordinates analysis showed that intestinal bacterial structure of limonene group cecum and colon was apparently separated from other groups. The relative abundance of Lactobacillus in cecum and colon in essential oil, limonene, linalool and citral groups was higher than that in the control group.

CONCLUSIONS

Orange essential oil and limonene, linalool and citral could affect the intestinal microflora of mice, and enhance the relative abundance of Lactobacillus. The intestinal bacterial structure of cecum and colon in the limonene group was quite different from other groups. This indicated a more obvious effect of limonene on intestinal bacteria, also resulting in significant changes in blood immune index and short-chain fatty acids in mice. © 2019 Society of Chemical Industry.

Antifungal Activity of Citrus Essential Oils

Citrus essential oils (CEOs) are a mixture of volatile compounds consisting mainly of monoterpene hydrocarbons and are widely used in the food and pharmaceutical industries because of their antifungal activities. To face the challenge of growing public awareness and concern about food and health safety, studies concerning natural biopreservatives have become the focus of multidisciplinary research efforts. In the past decades, a large amount of literature has been published on the antifungal activity of CEOs. This paper reviews the advances of research on CEOs and focuses on their in vitro and food antifungal activities, chemical compositions of CEOs, and the methods used in antifungal assessment. Furthermore, the antifungal bioactive components in CEOs and their potential mechanism of action are summarized. Finally, the applications of CEOs in the food industry are discussed in an attempt to provide new information for future utilization of CEOs in modern industries.