Isolation of the Main Biologically Active Substances and Phytochemical Analysis of Ginkgo biloba Callus Culture Extracts.

The work reveals the results of studying the content of biologically active substances in samples of extracts of Ginkgo biloba callus cultures. Callus cultures grown in vitro on liquid nutrient media were the objects of the study. Considering various factors affecting the yield of the target components during extraction, the volume fraction of the organic modifier in the extracting mixture, the temperature factor, and the exposure time were identified as the main ones. The maximum yield of extractive substances (target biologically active substances with a degree of extraction of at least 50%) from the samples of callus culture extracts was detected at a ratio of extragent of 70% ethanol, a temperature of 50 °C, and exposure time of 6 h. Flavonoids, such as luteolin, quercetin, isoramentin, kaempferol, and amentoflavone, were isolated in the extract samples. As a result of column chromatography, fractions of individual biologically active substances (bilobalide, ginkgolide A, B, and C) were determined. The proposed schemes are focused on preserving the nativity while ensuring maximum purification from associated (ballast) components. Sorbents (Sephadex LH-20, poly-amide, silica gel) were used in successive stages of chromatography with rechromatography. The degree of purity of individually isolated substances was at least 95%.

In vitro metabolism of tebuconazole, flurtamone, fenhexamid, metalaxyl-M and spirodiclofen in Cannabis sativa L. (hemp) callus cultures.

BACKGROUND: Cannabis sativa L. (hemp) is a medicinal plant producing various cannabinoids. Its consumption is legalized for medical use due to the alleged positive health effects of these cannabinoids. To satisfy the demand, C. sativa plants are propagated in contained growth chambers. During indoor propagation, pesticides usually are used to ensure efficient production. However, pesticide registration and safe application in C. sativa has not been investigated in detail. RESULTS: With this study the metabolic degradation of pesticides in recently established C. sativa callus cultures was examined. Tebuconazole, metalaxyl-M fenhexamid, flurtamone and spirodiclofen were applied at 10 µm for 21 days. Results were compared with metabolism data obtained from Brassica napus L., Glycine max (L.) Merr., Zea mays L. and Tritium aestivum L. callus cultures as well as in metabolism guideline studies. The successfully established C. sativa callus cultures were able to degrade pesticides by oxidation, demethylation, and cleavage of ester bonds in phase I, as well as glycosylation and conjugation with malonic acid in phase II and III. Initial metabolites were detected after Day (D)7 and were traced at D21. CONCLUSION: The resulting pathways demonstrate the same main degradation strategies as crop plants. Because metabolites could be the main residue, the exposure of consumers to these residues will be of high importance. We present here an in vitro assay for a first estimation of pesticide metabolism in C. sativa. © 2021 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Evaluation of the Conditions for the Cultivation of Callus Cultures of Hyssopus officinalis Regarding the Yield of Polyphenolic Compounds.

The cultivation of plants in the form of callus cultures constitutes a renewable source of secondary plant metabolites. The conditions for the cultivation of callus cultures affect the yield of target compounds. Callus cultures of Hyssopus officinalis were chosen for study. Nutrient media of various compositions were used for Hyssopus officinalis callus culture. For each culture, data on the quantitative contents of saponins, flavonoids and polyphenolic compounds, as well as antioxidant activity, were obtained. It was found that Murashige and Skoog medium supplemented with 1-naphthylacetic acid and kinetin led to the highest yield of secondary metabolites.

Influence of photoperiod on growth, bioactive compounds and antioxidant activity in callus cultures of Basella rubra L.

Basella rubra L. is an important green leafy vegetable vine and is known for its health benefits in traditional medicine. Light is a basic physical factor essential to the development and bioactive secondary metabolite production in in vitro callus cultures. The present study researched the impact of different photoperiods on biomass, bioactive compounds, and antioxidant activity in callus cultures of B. rubra. The in vitro seedling based cotyledonary leaf explants responded differently, when cultured on Murashige and Skoog (MS) medium with varying concentrations and combination of auxins and cytokinins. The best callus proliferation was found in MS medium with 0.1 mg.L-1 1-naphthaleneacetic acid (NAA) and 6 mg.L-1 6-benzylaminopurine (BAP), with greenish callus inception by about 2 weeks. The growth curve recorded for 6 weeks of culturing revealed that the photoperiod effect was found to be pivotal for acquiring biomass. At the fifth week, the continuous light supported maximum biomass (12.42 g) production followed by the 16:8 h photoperiod (9.02 g) and continuous darkness (4.28 g). The 80% ethanol extract of 1-week-old callus that grows under the 16:8 h photoperiod showed the highest total phenolic content (TPC) (74 mg.100 g-1 fresh weight, FW) when compared to all other extracts at different stages. The ferric reducing antioxidant power assay showed the highest (336.23 mg.100 g-1 FW) activity in methanol extractions of first-week callus cultures maintained in the continuous light condition. HPLC-UV identification and quantification of individual phenolics and flavonoids, such as gallic, trans-cinnamic, quercetin, protocatechuic and rutin, were highest in the callus cultures. The outcome of this study is significant to this plant, as B. rubra is familiar for its important health constituents with high-value bioactives and applications in the pharma and nutraceutical industries.

Strategy for early callus induction and identification of anti-snake venom triterpenoids from plant extracts and suspension culture of Euphorbia hirta L.

Euphorbia hirta L. from the family of Euphorbiaceae is an annual herb, which grows as a roadside weed in most tropical countries. It is prominently used by the traditional healers in rural India for the treatment of snakebites. However, the mechanisms and the major bioactive compounds behind its inhibition activity are relatively unknown. From our preliminary in silico studies, it was found that a group of pentacyclic triterpenoids from this plant are playing a major role in inhibiting the snake venom proteins. The present study was aimed at standardizing methods for obtaining callus from this medicinal plant at a much faster rate by hormone pretreatment of explants and, thus, by developing suspension cultures to obtain bioactive secondary metabolites in vitro. The results were promising that longer incubation of explants with hormone treatment showed early induction of callus. The major bioactive compounds responsible for the anti-snake venom activity were characterized from natural plant material as well as from suspension cultures, and the efficiency was found to be relatively high. The secondary metabolite analysis from suspension culture and natural plant extracts revealed that a major compound 'Taraxerol' and its derivatives was found abundant along with few other triterpenoids. This compound showed high inhibitory activity against pit viper snake venoms from our in silico studies with molecular docking tools. Hence, this study with identification of potential bioactive compounds against snake venom with standardization of In vitro culture methods would help in developing natural alternative medicine for snakebites in near future.

New triterpenic acids produced in callus culture from fruit pulp of Acca sellowiana (O. Berg) Burret.

The aim of this work was the study of the best conditions for obtaining a callus culture from the pulp of Acca sellowiana, and to perform a quali-quantitative analysis of the secondary metabolites yielded by the in vitro callus culture. To this end, callus was induced on both Murashige and Skoog and Gamborg B5 media containing various combinations of growth regulators. Three previously undescribed ursane-type triterpenoids, 2α,3ß,6α,23-tetrahydroxy-18α,19α-urs-20-en-28-oic acid, 2α,3ß,23-trihydroxy-18α,19α-urs-20-en-28-oic acid and 2α,3ß,6ß,23-tetrahydroxy-18α,19α-urs-20-en-28-oic acid were isolated from the methanolic extract of A. sellowiana culture and characterized by 1D and 2D NMR experiments. Moreover, the quali-quantitative analysis (ESI-MSn and GC-MS) also showed the presence of ß-sitosterol, phloridzin, oleanolic, ursolic, 3ß-hydroxy-18α,19α-urs-20-en-28-oic, maslinic, corosolic, 2α,3ß-dihydroxy-18α,19α-urs-20-en-28-oic, and tormentic acid.

Effect of in vitro morphogenesis on the production of podophyllotoxin derivatives in callus cultures of Linum album.

The anticancer compound podophyllotoxin and other related lignans can be produced in Linum album in vitro cultures, although their biosynthesis varies according to the degree of differentiation of the plant material. In general, L. album cell cultures do not form the same lignans as roots or other culture systems. Our aim was to explore how the lignan-producing capacity of organogenic cell masses is affected by the conditions that promote their formation and growth. Thus, L. album biomass obtained from plantlets was cultured in darkness or light, with or without the addition of plant growth regulators, and the levels of podophyllotoxin, methoxypodophyllotoxin and other related lignans were determined in each of these conditions. The organogenic capacity of the cell biomass grown in the different conditions was studied directly and also with light and scanning electronic microscopy, leading to the observation of.several somatic embryos and well-formed shoots. The main lignan produced was methoxypodophyllotoxin, whose production was clearly linked to the organogenic capacity of the cell biomass, which to a lesser extent was also the case for podophyllotoxin.

Phytochemical and biological study of callus cultures of Tulbaghia violacea Harv. Cultivated in Egypt.

As in vitro plant cultures are used extensively to produce bioactive metabolites, our goal was to establish calli from Tulbaghia violacea Harv. flowers and assess the tissue phytochemically and biologically. Murashige & Skoog medium(MS) + 22.6 µM 2,4-dichlorophenoxyacetic acid +2.2 µM benzylaminopurine induced callus from flowers. Gas chromatography/mass spectrometry(GC/MS) analyses of n-hexane extracts of calli(HC) and flowers(HF) revealed 33 and 32 components(92.6 and 98.5%, respectively). Hydrocarbons were predominant in HC (55.0%), whereas a higher percentage of oxygenated compounds was found in HF(74.6%). Trans(E)-anethole(39.1%) and 16-hentriacontanone (30.3%) dominated in HF and HC, respectively. However, sulphur compounds were only detected in HF. Quantitative estimation of thiosulphinates, phenolics, flavonoids and saponins in ethanolic extracts of calli(EC) and flowers(EF) showed much higher contents in EF. Antioxidant, antimicrobial and cytotoxic screening of extracts demonstrated that EF was the most potent, followed by HF and EC; conversely, HC was inactive. Although HC and EC were less biologically active, these calli could be an alternative source of bioactive metabolites.

Calcium pectinate gel beads obtained from callus cultures pectins as promising systems for colon-targeted drug delivery.

Low methyl-esterified pectins obtained from the cell walls of the campion (SV, SV>300), tansy (TV, TV>300) and duckweed (LM, LM>300) callus cultures and apple pectin (AP, Classic AU 701) were used as the carriers for colon delivery of prednisolone. The pectins with molecular weight more than 300kDa (SV>300, TV>300, LM>300) formed gels which exhibited the higher gel strength. The higher gel strength of these gels appeared to be related to the higher Mw and the lower degree of methylesterification (DE) of these pectins. Release aspects of prednisolone in the simulated gastric (pH 1.25), intestinal (pH 7.0) and colonic (pH 7.0+pectinase) media were investigated. The LM-5%, AP-3% and AP-5% beads destroyed in simulated intestinal medium probably due to the higher DE of the LM and AP pectins. The SV>300-3% and TV>300-3% prednisolone loaded bead systems showed a high stability at pH 1.25 and pH 7.0. Prednisolone release occurred in a larger extent in colonic medium due to the enzymatic erosion of the beads. The SV>300-3% and TV>300-3% particles showed a more controlled release that appeared to be related to the lower DE, rhamnogalacturonan content, rhamnogalacturonan I branching and the higher linearity and Mw of the TV>300 and SV>300 pectins, as well as to the higher gel strength. This in vitro study suggests that calcium pectinate gel beads obtained from callus cultures pectins can be proposed as potential systems for colon-targeted drug delivery.

[Flavonoid glycosides from callus cultures of Dysosma versipellis].

Various chromatographic techniques, including silica gel column chromatography, Sephadex LH-20, preparative thin-layer chromatography, and preparative HPLC, were employed to isolate the chemical constituents from callus cultures of Dysosma versipellis. Structures of the compounds were elucidated based on UV, IR, MS and NMR spectroscopic data analysis. Totally, seven flavonoid glycosides were isolated from the 95% ethanol extract of the callus cultures and identified as kaempferol-3-O-[6″-(3″'-methoxy)-malonyl]-ß-D-glucopyranoside(1), kaempferol-3-O-(6″-O-acetyl)-ß-D-glucopyranoside(2), kaempferide-3-O-ß-D-glucopyranoside(3), kaempferol-3-O-ß-D-glucopyranoside(4), isoquercitrin(5), quercetin-4'-O-ß-D-glucopyranoside(6) and kaempferol-3-(6″-malonyl)-ß-D-glucopyranoside(7), respectively.All these compounds were isolated from callus cultures of D. versipellis for the first time.Compounds 1, 2, 3, 6 and 7 were firstly obtained from plant materials of D. versipellis, and compound 1 was a new compound.

Antimicrobial activity of Anonna mucosa (Jacq.) grown in vivo and obtained by in vitroculture.

Brazilian flora includes numerous species of medicinal importance that can be used to develop new drugs. Plant tissue culture offers strategies for conservation and use of these species allowing continuous production of plants and bioactive substances. Annona mucosa has produced substances such as acetogenins and alkaloids that exhibit antimicrobial activities. The widespread use of antibiotics has led to an increase in multidrug-resistant bacteria, which represents a serious risk of infection. In view of this problem, the aim of this work was to evaluate the antibacterial potential of extracts of A. mucosa obtained by in vitro techniques and also cultured under in vivo conditions. Segments from seedlings were inoculated onto different culture media containing the auxin picloram and the cytokinin kinetin at different concentrations. The calluses obtained were used to produce cell suspension cultures. The materials were subjected to methanol extraction and subsequent fractionation in hexane and dichloromethane. The antimicrobial activity against 20 strains of clinical relevance was evaluated by the macrodilution method at minimum inhibitory and minimum bactericidal concentrations. The extracts showed selective antimicrobial activity, inhibiting the growth of Streptococcus pyogenes and Bacillus thuringiensis at different concentrations. The plant tissue culture methods produced plant materials with antibacterial properties, as well as in vivo grown plants. The antibacterial activity of material obtained through biotechnological procedures of A. mucosa is reported here for the first time.

Antimicrobial activity of Anonna mucosa (Jacq.) grown in vivo and obtained by in vitroculture

Brazilian flora includes numerous species of medicinal importance that can be used to develop new drugs. Plant tissue culture offers strategies for conservation and use of these species allowing continuous production of plants and bioactive substances. Annona mucosa has produced substances such as acetogenins and alkaloids that exhibit antimicrobial activities. The widespread use of antibiotics has led to an increase in multidrug-resistant bacteria, which represents a serious risk of infection. In view of this problem, the aim of this work was to evaluate the antibacterial potential of extracts of A. mucosa obtained by in vitro techniques and also cultured under in vivo conditions. Segments from seedlings were inoculated onto different culture media containing the auxin picloram and the cytokinin kinetin at different concentrations. The calluses obtained were used to produce cell suspension cultures. The materials were subjected to methanol extraction and subsequent fractionation in hexane and dichloromethane. The antimicrobial activity against 20 strains of clinical relevance was evaluated by the macrodilution method at minimum inhibitory and minimum bactericidal concentrations. The extracts showed selective antimicrobial activity, inhibiting the growth of Streptococcus pyogenes and Bacillus thuringiensis at different concentrations. The plant tissue culture methods produced plant materials with antibacterial properties, as well as in vivo grown plants. The antibacterial activity of material obtained through biotechnological procedures of A. mucosa is reported here for the first time.