Rosa platyacantha Schrenk from Kazakhstan—Natural Source of Bioactive Compounds with Cosmetic Significance

Plants belonging to the Rosa genus are known for their high content of bioactive molecules and broad spectrum of healing and cosmetic activities. Rosa platyacantha Schrenk is a wild-type species abundant in the mountainous regions of Kazakhstan. The phytochemical composition as well as the bioactivity of R. platyacantha extracts have not been fully investigated to date. In this study, various parts of R. platyacantha plant, collected in Almaty region, Kazakhstan, were used to prepare five hydroalcoholic extracts (R1–R5). The extracts were compared for the content of phytochemicals and selected biological activities, which are important for the potential cosmetic application of R. platyacantha. Extract R3, prepared from flower buds, showed the most significant antioxidant and tyrosinase inhibitory potential, decreasing the monophenolase and diphenolase activities of tyrosinase. Extract R3 showed also collagenase inhibitory activity and cytotoxicity against human melanoma cells A375, being less cytotoxic for noncancerous skin keratinocytes HaCaT. Analysis of fractions E and F, obtained from R3 extracts, revealed that quercetin, kaempferol, rutin, and their derivatives are more likely responsible for the tyrosinase inhibitory properties of R. platyacantha extracts.     

Can Extracts from the Leaves and Fruits of the Cotoneaster Species Be Considered Promising Anti-Acne Agents?

This study aimed to evaluate the phenolic profile and biological activity of the extracts from the leaves and fruits of Cotoneaster nebrodensis and Cotoneaster roseus. Considering that miscellaneous species of Cotoneaster are thought to be healing in traditional Asian medicine, we assumed that this uninvestigated species may reveal significant therapeutic properties. Here, we report the simultaneous assessment of chemical composition as well as biological activities (antioxidant, anti-inflammatory, antibacterial, and cytotoxic properties) of tested species. Complementary LC-MS analysis revealed that polyphenols (especially flavonoids and proanthocyanidins) are the overriding phytochemicals with the greatest significance in tested biological activities. In vitro chemical tests considering biological activities revealed that obtained results showed different values depending on concentration, extraction solvent as well as phenolic content. Biological assays demonstrated that the investigated extracts possessed antibacterial properties and were not cytotoxic toward normal skin fibroblasts. Given the obtained results, we concluded that knowledge of the chemical composition and biological activities of investigated species are important to achieve a better understanding of the utilization of these plants in traditional medicine and be useful for further research in their application to treat various diseases, such as skin disorders.     

Rhamnus pallasii subsp. sintenisii fruit,leaf, bark and root: Phytochemical profiles and biological activities

The genus Rhamnus has received a lot of interest as a source of phenolic chemicals. There have been no reports on the phytochemicals and biological activities of R. pallasii subsp. sintenisii various morphological components (fruit, leaf, bark, and root) in Iran to yet. Two crude ether petroleum (EP) and hydro-methanolic (HM) extracts were obtained from the separate parts. The antioxidant and antibacterial capabilities of the extracts, as well as their phytochemical screening (total phenolic, flavonoid, phenolic acid, and anthocyanin concentrations), were measured. Furthermore, the phytochemical profiles of EP and HM extracts were determined using GC–MS and LC-ESI–MS, respectively. LC-ESI-MS detected 59 chemicals in HM extracts, including flavonoids (62.71 %), phenolic acids (10.16 %), and anthraquinones (16.94 %). Furthermore, the predominant group components in EP extracts examined by GC–MS were fatty acids (58.82%), phenolic compounds (49.28%), and hydrocarbons (35.15 to 59.45 %). In terms of biological testing (DPPH radical scavenging and anti-bacterial activity), all examined extracts, particularly the fruit, had the highest activities in both assays (IC₅₀: 7.52 to 22.39 µg/ml and MIC: 0.39 to 3.12 mg/ml), owing to their high phenolic content. As a result, individual morphological elements of the species might be thought of as natural antioxidant and antibacterial agents.     

Comparison of Phytochemical Contents,Antioxidant and Antibacterial Activities of Various Solvent Extracts Obtained from ‘Maluma’ Avocado Pulp Powder

Although avocado is a superfood rich in phytochemicals with high antioxidant activities, studies on the antibacterial properties of its pulp are limited, except for seed and peel portions. In this study, three types of solvent (acetone, methanol, and diethyl ether) were used to obtain the extracts from “Maluma” avocado pulp powder prepared by infrared drying. The extracts were analyzed for total polyphenols, phytopigments (total chlorophylls and carotenoids), antioxidant activities (ferric-reducing antioxidant power (FRAP), 2,2-Diphenyl-1-picrylhydrazyl (DPPH), and 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) assays), and antibacterial activities against seven pathogens (Shigella sonnei ATCC 9290, Escherichia coli ATCC 8739, Salmonella typhi ATCC 6539, Vibrio parahaemolyticus ATCC 17802, Proteus mirabilis ATCC 25933, Staphylococcus aureus ATCC 6538, and Bacillus cereus ATCC 11778). The results showed that the acetone solvent could extract the highest polyphenols and chlorophylls with the highest antioxidant activity in terms of ABTS and DPPH assays. In contrast, diethyl ether exhibited the most significant content of carotenoids and FRAP values. However, the methanol extract was the best solvent, exerting the strongest antibacterial and meaningful antioxidant activities. For the bacterial activities, Gram-positive pathogens (Bacillus cereus and Staphylococcus aureus) were inhibited more efficiently by avocado extracts than Gram-negative bacteria. Therefore, the extracts from avocado powder showed great potential for applications in food processing and preservation, pharmaceuticals, and cosmetics.     

In vitro biological activities and preliminary phytochemical screening of different extracts from Achillea sintenisii Hub- Mor

This study was designed to investigate in vitro biological activities and phytochemical composition of aqueous and ethanolic extracts from Achillea sintenisii Hub- Mor. (AS). To determine the chemical composition of AS extracts, phytochemical analyses were performed by using HPLC–ESI-Q-TOF-MS-MS. Afterwards, both extracts were investigated in terms of their effect on fibroblast proliferation, collagen synthesis, and hydrogen peroxide-induced damage. In addition to cell culture analysis, antibacterial, antioxidant, hyaluronidase inhibitory activities and total phenolic contents of the extracts were analyzed in cell-free systems. Our results demonstrated that the aqueous and ethanolic extracts did not show cytotoxic activity on fibroblasts, on the contrary, promoted fibroblast proliferation. Both AS extracts potently inhibited hyaluronidase activity and the inhibitory effect of ethanolic extract was comparable with the positive control, especially at high concentrations. The aqueous extract was the potent stimulator of collagen synthesis at 200 µg/mL concentration. Although the ethanolic extract showed antibacterial activity against all gram-positive bacteria, the aqueous extract was only effective against K. pneumoniae and B. subtilis. The ability of AS extracts, which have a rich phenolic compound content (≥50 mg GAE/g), to scavenge free radicals and protect fibroblasts against hydrogen peroxide-induced damage can be considered as a result of their antioxidant potential. Our findings scientifically support the widespread use of this plant, by demonstrating the pharmacological properties of the extracts.     

Important insights from the antimicrobial activity of Calotropis procera

Calotropis procera (family Apocynaceae) is a valuable medicinal plant as it contains many valuable phytochemicals such as glycosides (mostly cardenolides), flavonoids, triterpenes, alkaloids, steroids, saponins, proteins and enzymes. Multiparous biological activities such as anti-inflammatory, antioxidant, anticancer, wound healing and wideranging antimicrobial activities of C. procera have been well investigated and reported. The main aim of this review was to present the encompassing information regarding antimicrobial activities of C. procera latex, different crude extracts and some isolated compounds which have been tested for antimicrobial property. Comprehensive data extracted from earlier as well as recently published original articles regarding antibacterial, antifungal, anti-protozoal and antiviral properties of C. procera were discussed and summarised in tabular forms. The compiled data comprised of plant parts, geographical origin, type of tested extracts/fractions, test model, used doses, tested microorganisms, obtained results and relevant references. In addition, the isolated antimicrobial pure compounds of C. procera are also discussed in a separate section. The analysis and information presented in this review identified the existing critical knowledge gaps in the research and also explored the future perspectives and further research opportunities of C. procera.     

Nettle (Urtica dioica L.) as a source of antioxidant and anti-aging phytochemicals for cosmetic applications

Nettle (Urtica dioica L.) is a herbaceous perennial that has been used for centuries in folk medicine. More recently, nettle extracts have also been used in cosmetics because of the many benefits of their topical application for skin health. Their potential anti-aging action is of particular interest and is primarily ascribed to their antioxidant capacity. Here, using an experimental design approach and a clustering analysis, we linked the phytochemical composition of nettle extracts to their biological activities. This approach confirmed the antioxidant capacity of nettle extracts as well as providing the first evidence of another mechanism for their anti-aging potential involving the inhibition of enzyme activities, such as elastase and collagenase. We attributed these inhibitory effects to ursolic acid and quercetin present in the nettle extracts. Our results also demonstrated the possibility of extracting ursolic acid, quercetin and other phenolic compounds differentially to obtain an extract with a strong antioxidant capacity and anti-aging activities toward both elastase and collagenase. This could be of particular interest for cosmetic applications of nettle extracts.     

Polyphenol Rich Ajuga bracteosa Transgenic Regenerants Display Better Pharmacological Potential

Ajuga bracteosa Wall. ex Benth. is an endangered medicinal herb traditionally used against different ailments. The present study aimed to create new insight into the fundamental mechanisms of genetic transformation and the biological activities of this plant. We transformed the A. bracteosa plant with rol genes of Agrobacterium rhizogenes and raised the regenerants from the hairy roots. These transgenic regenerants were screened for in vitro antioxidant activities, a range of in vivo assays, elemental analysis, polyphenol content, and different phytochemicals found through HPLC. Among 18 polyphenolic standards, kaempferol was most abundant in all transgenic lines. Furthermore, transgenic line 3 (ABRL3) showed maximum phenolics and flavonoids content among all tested plant extracts. ABRL3 also demonstrated the highest total antioxidant capacity (8.16 ± 1 μg AAE/mg), total reducing power, (6.60 ± 1.17 μg AAE/mg), DPPH activity (IC50 = 59.5 ± 0.8 μg/mL), hydroxyl ion scavenging (IC50 = 122.5 ± 0.90 μg/mL), and iron-chelating power (IC50 = 154.8 ± 2 μg/mL). Moreover, transformed plant extracts produced significant analgesic, anti-inflammatory, anticoagulant, and antidepressant activities in BALB/c mice models. In conclusion, transgenic regenerants of A. bracteosa pose better antioxidant and pharmacological properties under the effect of rol genes as compared to wild-type plants.     

Validation of a High-Performance Liquid Chromatography with Photodiode Array Detection Method for the Separation and Quantification of Antioxidant and Skin Anti-Aging Flavonoids from Nelumbo nucifera Gaertn. Stamen Extract

Nelumbo nucifera Gaertn., or the so-called sacred lotus, is a useful aquatic plant in the Nelumbonaceae family that has long been used to prepare teas, traditional medicines as well as foods. Many studies reported on the phytochemicals and biological activities of its leaves and seeds. However, to date, only few studies were conducted on its stamen, which is the most important ingredient for herbal medicines, teas and other phytopharmaceutical products. Thus, this present study focuses on the following: (1) the application of high-performance liquid chromatography with photodiode array detection for a validated separation and quantification of flavonoids from stamen; (2) the Nelumbo nucifera stamen’s in vitro and in cellulo antioxidant activities; as well as (3) its potential regarding the inhibition of skin aging enzymes for cosmetic applications. The optimal separation of the main flavonoids from the stamen ethanolic extract was effectively achieved using a core-shell column. The results indicated that stamen ethanolic extract has higher concentration of in vitro and in cellulo antioxidant flavonoids than other floral components. Stamen ethanolic extract showed the highest protective effect against reactive oxygen/nitrogen species formation, as confirmed by cellular antioxidant assay using a yeast model. The evaluation of potential skin anti-aging action showed that the stamen extract has higher potential to inhibit tyrosinase and collagenase compared with its whole flower. These current findings are the first report to suggest the possibility to employ N. nucifera stamen ethanolic extract as a tyrosinase and collagenase inhibitor in cosmetic applications, as well as the utility of the current separation method.     

Transgenic Artemisia dubia WALL showed altered phytochemistry and pharmacology

The rol genes have been shown to enhance the production of secondary metabolites in plants. This report examines the effect of trans-genes (rol ABC) on possible high production of biologically important phytochemicals and enhanced pharmacological activities. Three transgenic lines (1, 2 and 3) of Artemisia dubia WALL (transformed with Agrobacterium tumefaciens harboring rol ABC genes) were subjected to phytochemical analysis and pharmacological studies. A great variation in phytochemistry and the pharmacological activities was observed not only between the transgenic and non-transgenic control plants but also among the transgenic lines itself. Comparative chemical profile obtained via HPLC, TLC and spectrophotometry showed high degree of variations in the quantity of phytochemicals. An increased production of total flavonoids (71.1% in transgenic line 2) and total phenolics (110.8% in transgenic line 1), increase in caffeic acid and catechin and a decrease in gallic acid content in the extracts of transformed plants compared to the untransformed control plants was decreased. In case of pharmacological activities, moderate to high level increase in antimicrobial (antibacterial and antifungal) activities, cytotoxicity (14.1%), antitumor (29%) and antioxidant activities (23.9%) was observed (in transgenic line 2). In general all the three transgenic lines under study showed improvement in their pharmacological activities in the order of transgenic line 2 > 1 > 3 > control. The implication of these findings will help to meet the increasing demand of pharmacologically important compounds.     

Teucrium polium (L.): Phytochemical Screening and Biological Activities at Different Phenological Stages

The aim of the present study was to investigate the changes in the content of phytochemical compounds and in vitro antioxidant, antibacterial, and anti-inflammatory activities of Teucrium polium L. aerial parts and root methanolic extracts at different phenological stages (vegetative, flowering, and seeding). The T. polium extracts were analyzed using gas chromatography–mass spectrometry (GC-MS), and their antioxidant properties were tested with the 2,2-diphenyl-1-picrylhydrazyl (DPPH), nitric oxide (NO), ferrous ions (Fe²⁺), and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) methods. Forty-nine compounds were identified with the majority of germacrene D, t-cadinol, β-pinene, carvacrol, bicyclogermacrene, α-pinene, and limonene. The results show that the extracts significantly differ between different phenological stages of the plant material used in terms of the phytochemical composition (total phenolic compounds, total flavonoids, total alkaloids, and total saponin contents) and bioactivities (antioxidant, antibacterial, and anti-inflammatory) (p < 0.05). The highest total contents of phenolics (72.4 ± 2.5 mg gallic acid equivalent (GAE)/g dry weight), flavonoids (36.2 ± 3.1 mg quercetin equivalent (QE)/g dry weight), alkaloids (105.7 ± 2.8 mg atropine equivalent (AE)/g dry weight), and saponins (653 ± 6.2 mg escin equivalent (EE)/g dry weight), as well as antioxidant, antibacterial, and anti-inflammatory activities, were measured for the extract of the aerial parts obtained at the flowering stage. The minimum inhibitory concentration (MIC) values for the extracts were varied within 9.4–300 µg/mL, while the minimum bactericidal concentration (MBC) values were varied within 18.75–600 µg/mL. In addition, they were more active on Gram-positive bacteria than Gram-negative bacteria. The data of this work confirm that the T. polium extracts have significant biological activity and hence can be used in the pharmaceutical industry, clinical applications, and medical research, as well as cosmetic and food industries.     

Epigenetic Modifiers Affect the Bioactive Compounds Secreted by an Endophyte of the Tropical Plant Piper longum

Seven endophytic fungi were isolated from the tropical medicinal plant Piper longum L. After preliminary screening, Phomopsis heveicola was selected for the epigenetic activation treatments. The antibacterial, antifungal, and antioxidant potentials of crude extracts obtained from the treatments (with and without epigenetic modifiers) were analyzed in vitro. The extracts inhibited growth of the human pathogens Pseudomonas aeruginosa, Shigella sonnei, Streptococcus pyogenes, and Salmonella typhi, as well as the phytopathogens Puccinia recondita, Rhizoctonia solani, Phytophthora infestans, and Botrytis cinerea. Furthermore, DPPH-scavenging activity was higher in valproic acid treated extracts. Volatile chemicals with known biological activities (measured with GC-MS/MS), were released in the valproic acid treatment. The antimicrobial potentials of the extracts were confirmed using MRM/MS analysis. The experiments revealed a new promising endophytic fungus, P. heveicola, to be utilized in biological plant protection and in biomedical applications.     

Production of Verbascoside,Isoverbascoside and Phenolic Acids in Callus,Suspension, and Bioreactor Cultures of Verbena officinalis and Biological Properties of Biomass Extracts

Callus, suspension and bioreactor cultures of Verbena officinalis were established, and optimized for biomass growth and production of phenylpropanoid glycosides, phenolic acids, flavonoids and iridoids. All types of cultures were maintained on/in the Murashige and Skoog (MS) media with 1 mg/L BAP and 1 mg/L NAA. The inoculum sizes were optimized in callus and suspension cultures. Moreover, the growth of the culture in two different types of bioreactors—a balloon bioreactor (BB) and a stirred-tank bioreactor (STB) was tested. In methanolic extracts from biomass of all types of in vitro cultures the presence of the same metabolites—verbascoside, isoverbascoside, and six phenolic acids: protocatechuic, chlorogenic, vanillic, caffeic, ferulic and rosmarinic acids was confirmed and quantified by the HPLC-DAD method. In the extracts from lyophilized culture media, no metabolites were found. The main metabolites in biomass extracts were verbascoside and isoverbascoside. Their maximum amounts in g/100 g DW (dry weight) in the tested types of cultures were as follow: 7.25 and 0.61 (callus), 7.06 and 0.48 (suspension), 7.69 and 0.31 (BB), 9.18 and 0.34 (STB). The amounts of phenolic acids were many times lower, max. total content reached of 26.90, 50.72, 19.88, and 36.78 mg/100 g DW, respectively. The highest content of verbascoside and also a high content of isoverbascoside obtained in STB (stirred-tank bioreactor) were 5.3 and 7.8 times higher than in extracts from overground parts of the parent plant. In the extracts from parent plant two iridoids—verbenalin and hastatoside, were also abundant. All investigated biomass extracts and the extracts from parent plant showed the antiproliferative, antioxidant and antibacterial activities. The strongest activities were documented for the cultures maintained in STB. We propose extracts from in vitro cultured biomass of vervain, especially from STB, as a rich source of bioactive metabolites with antiproliferative, antioxidant and antibacterial properties.     

Antioxidant and Cytoprotective Properties of Plant Extract from Dry Flowers as Functional Dyes for Cosmetic Products

Nowadays, natural dyes are expected by the cosmetic and food industries. In contrast to synthetic dyes, colorants derived from natural sources are more environmentally friendly and safer for human health. In this work, plant extracts from Gomphrena globasa L., Clitoria ternatea L., Carthamus tinctorius L., Punica granatum L. and Papaver rhoeas L. as the natural and functional dyes for the cosmetics industry were assessed. Cytotoxicity on keratinocyte and fibroblast cell lines was determined as well as antioxidant and anti-aging properties by determining their ability to inhibit the activity of collagenase and elastase enzymes. In addition, the composition of the extracts was determined. The obtained extracts were also applied in face cream formulation and color analyses were performed. It has been shown that the obtained extracts were characterized by no cytotoxicity and a high antioxidant potential. The extracts also show strong ability to inhibit the activity of collagenase and moderate ability to inhibit elastase and provide effective and long-lasting hydration after their application on the skin. Application analyses showed that the extracts of P. rhoeas L., C. ternatea L. and C. tinctorius L. can be used as effective cosmetic dyes that allow for attainment of an intense and stable color during the storage of the product. The extracts of P. granatum L. and G. globasa L., despite their beneficial effects as active ingredients, did not work effectively as cosmetic dyes, because cosmetic emulsions with these extracts did not differ significantly in color from emulsions without the extract.     

Illicium verum (Star Anise) and Trans-Anethole as Valuable Raw Materials for Medicinal and Cosmetic Applications

Illicium verum Hook f. (star anise) is considered an important species in Traditional Chinese Medicine and is also used in contemporary medicine in East Asian countries. It occurs in natural habitats in southeastern parts of China and Vietnam, and is cultivated in various regions in China. The raw materials—Anisi stellati fructus and Anisi stellati aetheroleum obtained from this species exhibit expectorant and spasmolytic activities. The European Pharmacopoeia (4th edition) indicates that these raw materials have been used in allopathy since 2002. The biological activities of the above-mentioned raw materials are determined by the presence of valuable secondary metabolites such as monoterpenoids, sesquiterpenoids, phenylpropanoids, and flavonoids. Recent pharmacological studies on fruit extracts and the essential oil of this species have confirmed their antibacterial, antifungal, anti-inflammatory, and antioxidant activities and thus their medicinal and cosmetic value. The aim of this review was to examine the progress of phytochemical and pharmacological studies that focused on possible cosmetic applications. In addition to fruit extracts and essential oil, the current consensus on the safety of trans-anethole, which is the main compound of essential oil used in cosmetology, is underlined here.     

Zanthoxylum Species: A Comprehensive Review of Traditional Uses,Phytochemistry, Pharmacological and Nutraceutical Applications

Zanthoxylum species (Syn. Fagara species) of the Rutaceae family are widely used in many countries as food and in trado-medicinal practice due to their wide geographical distribution and medicinal properties. Peer reviewed journal articles and ethnobotanical records that reported the traditional knowledge, phytoconstituents, biological activities and toxicological profiles of Z. species with a focus on metabolic and neuronal health were reviewed. It was observed that many of the plant species are used as food ingredients and in treating inflammation, pain, hypertension and brain diseases. Over 500 compounds have been isolated from Z. species, and the biological activities of both the plant extracts and their phytoconstituents, including their mechanisms of action, are discussed. The phytochemicals responsible for the biological activities of some of the species are yet to be identified. Similarly, biological activities of some isolated compounds remain unknown. Taken together, the Z. species extracts and compounds possess promising biological activities and should be further explored as potential sources of new nutraceuticals and drugs.     

Shoot Multiplication and Callus Induction of Labisia pumila var. alata as Influenced by Different Plant Growth Regulators Treatments and Its Polyphenolic Activities Compared with the Wild Plant

This study aims to investigate whether the in vitro-cultured L. pumila var. alata has higher antioxidant activity than its wild plant. An 8-week-old L. pumila var. alata nodal segment and leaf explants were cultured onto Murashige and Skoog (MS) medium supplemented with various cytokinins (zeatin, kinetin, and 6-benzylaminopurine (BAP)) for shoot multiplication and auxins (2,4-dichlorophenoxyacetic acid (2,4-D) and picloram) for callus induction, respectively. The results showed that 2 mg/L zeatin produced the optimal results for shoot and leaf development, and 0.5 mg/L 2,4-D produced the highest callus induction results (60%). After this, 0.5 mg/L 2,4-D was combined with 0.25 mg/L cytokinins and supplemented to the MS medium. The optimal results for callus induction (100%) with yellowish to greenish and compact texture were obtained using 0.5 mg/L 2,4-D combined with 0.25 mg/L zeatin. Leaves obtained from in vitro plantlets and wild plants as well as callus were extracted and analyzed for their antioxidant activities (DPPH and FRAP methods) and polyphenolic properties (total flavonoid and total phenolic content). When compared with leaf extracts of in vitro plantlets and wild plants of L. pumila var. alata, the callus extract displayed significantly higher antioxidant activities and total phenolic and flavonoid content. Hence, callus culture potentially can be adapted for antioxidant and polyphenolic production to satisfy pharmaceutical and nutraceutical needs while conserving wild L. pumila var. alata.     

The Isorhamnetin-Containing Fraction of Philippine Honey Produced by the Stingless Bee Tetragonula biroi Is an Antibiotic against Multidrug-Resistant Staphylococcus aureus

Honey exhibits antibacterial and antioxidant activities that are ascribed to its diverse secondary metabolites. In the Philippines, the antibacterial and antioxidant activities, as well as the bioactive metabolite contents of the honey, have not been thoroughly described. In this report, we investigated the in vitro antibacterial and antioxidant activities of honey from Apis mellifera and Tetragonula biroi, identified the compound responsible for the antibacterial activity, and compared the observed bioactivities and metabolite profiles to that of Manuka honey, which is recognized for its antibacterial and antioxidant properties. The secondary metabolite contents of honey were extracted using a nonionic polymeric resin followed by antibacterial and antioxidant assays, and then spectroscopic analyses of the phenolic and flavonoid contents. Results showed that honey extracts produced by T. biroi exhibits antibiotic activity against Staphylococcal pathogens as well as high antioxidant activity, which are correlated to its high flavonoid and phenolic content as compared to honey produced by A. mellifera. The bioassay-guided fractionation paired with Liquid Chromatography Mass Spectrometry (LCMS) and tandem MS analyses found the presence of the flavonoid isorhamnetin (3-methylquercetin) in T. biroi honey extract, which was demonstrated as one of the compounds with inhibitory activity against multidrug-resistant Staphylococcus aureus ATCC BAA-44. Our findings suggest that Philippine honey produced by T. biroi is a potential nutraceutical that possesses antibiotic and antioxidant activities.     

Elicitation of Submerged Adventitious Root Cultures of Stevia rebaudiana with Cuscuta reflexa for Production of Biomass and Secondary Metabolites

Stevia rebaudiana is an important medicinal plant that belongs to the Asteraceae family. The leaves of Stevia rebaudiana are a rich source of many health-promoting agents such as polyphenols, flavonoids, and steviol glycoside, which play a key role in controlling obesity and diabetes. New strategies such as the elicitation of culture media are needed to enhance the productivity of active components. Herein, the Cuscuta reflexa extracts were exploited as elicitors to enhance the productivity of active components. Cuscuta reflexa is one of the parasitic plants that has the ability to elongate very fast and cover the host plant. Consequently, it may be possible that the addition of Cuscuta reflexa extracts to adventitious root cultures (ADR) of Stevia rebaudiana may elongate the root more than control cultures to produce higher quantities of the desired secondary metabolites. Therefore, the main objective of the current study was to investigate the effect of Cuscuta reflexa extract as a biotic elicitor on the biomass accumulation and production of antioxidant secondary metabolite in submerged adventitious root cultures of Stevia rebaudiana. Ten different concentrations of Cuscuta reflexa were added to liquid media containing 0.5 mg/L naphthalene acetic acid (NAA). The growth kinetics of adventitious roots was investigated for a period of 49 days with an interval of 7 days. The maximum biomass accumulation (7.83 g/3 flasks) was observed on medium containing 10 mg/L extract of Cuscuta reflexa on day 49. As the concentration of extract increases in the culture media, the biomass gradually decreases after 49 days of inoculation. In this study, the higher total phenolics content (0.31 mg GAE/g-DW), total flavonoids content (0.22 mg QE/g-DW), and antioxidant activity (85.54%) were observed in 100 mg/L treated cultures. The higher concentration (100 mg/L) of Cuscuta reflexa extract considerably increased the total phenolics content (TPC), total phenolics production (TPP), total flavonoids content (TFC), total flavonoids production (TFP), total polyphenolics content (TPPC), and total polyphenolics production (TPPP). It was concluded that the extract of Cuscuta reflexa moderately improved biomass accumulation but enhanced the synthesis of phenolics, flavonoids, and antioxidant activities. Here, biomass’s independent production of secondary metabolites was observed with the addition of extract. The present study will be helpful to scale up adventitious roots culture into a bioreactor for the production of secondary metabolites rather than biomass accumulation in medicinally important Stevia rebaudiana.