Search

Objective: To evaluate anti-psoriatic activity of Coleus forskohlii in rats with imiquimod-induced psoriasis. Methods: Imiquimod was used to induce psoriasis in rats. Body weight, skin thickness, erythema, scaling, spleen weight, and histological alternations were measured to assess the effect of Coleus forskohlii. Furthermore, an emulgel formulation containing Coleus forskohlii 10% was prepared and characterized along with its ex vivo permeation studies. Results: The emulgel formulation containing Coleus forskohlii 10% had a pH of 5.40±0.36, with optimum spreadability of (31.67±2.08) g/(cms) and viscosity of (15 966.67±1 274.10) cps, and enhanced both the rate and the extent of drug permeation through psoriatic skin. In an ex vivo study, the quantity of drug permeated (19.18%), deposited (52.38%), and drug remaining in the donor compartments (28.31%) was satisfactory. Coleus forskohlii significantly alleviated imiquimod-induced psoriasis by increasing glutathione and superoxide dismutase activity, decreasing malondialdehyde and nitric oxide levels, and alleviating histological alternations in rat skin. Conclusions: Coleus forskohlii can alleviate imiquimod-induced psoriasis, which may be used as a therapeutic candidate for the treatment of psoriasis.

Background: Patients taking multiple drugs and various health foods often develop acute hepatitis. We hypothesized that the interaction between health foods and drug metabolism was the cause of severe liver injury in these patients. Therefore, we studied changes in the activity of the drug-metabolizing enzyme, cytochrome P450 (CYP), using slimming health food extracts and elucidated the molecular mechanism of liver injury onset through hepatotoxicity evaluation. Methods For cytotoxicity testing, health food extract samples were added to HepG2 cells derived from hepatic parenchymal cells and culture medium, and cell viability was calculated 48 h after culture. To evaluate CYP3A4 induction, 3-1-10 cells constructed with a reporter linked to CYP3A4 gene were used, and reporter activity was measured 48 h after culture. Results: In the chronological order of the slimming health food intake history of the patient, niacinamide and Gymnema sylvestre extracts strongly inhibited HepG2 cell viability. In contrast, dietary supplements A and Coleus forskohlii extract strongly induced CYP3A4 reporter activity. To confirm CYP3A4 induction in humans, humanized CYP3A/pregnane X receptor (PXR) mice were treated with forskolin. CYP3A4 mRNA expression levels were elevated 3.9 times compared to that of the control group (P < 0.05). Conclusion: Coleus forskohlii extract showed the strongest transcriptional activation of CYP3A4 gene. In a mouse model of human-type drug metabolism, forskolin induced CYP3A4 transcription. Thus, we concluded that CYP3A4 induction by Coleus forskohlii is one of the causes of crucial hepatocellular injury, which is a type of liver injury caused by the active metabolite of acetaminophen produced by CYP3A4. [ABSTRACT FROM AUTHOR]

Coleus forskohlii Briq., a medicinal plant from the Lamiaceae family, has been utilized worldwide to treat various disorders. The primary active compound in this plant is forskolin, a diterpene that accumulates in its rhizome. This study aims to assess the in vitro culture of C. forskohlii by investigating the effects of different concentrations of auxin hormone (1 and 2 mg L-1) and zinc oxide (ZnO) nanoparticles (10 and 20 ppm) as elicitors on biometrical traits related to rooting as well as forskolin content. Each treatment was replicated three times, and the results were analyzed using SPSS version 20. We observed that most traits examined decreased in samples treated with 1 mg L-1 of IAA hormone. In contrast, samples treated with 2 mg L-1 of IAA exhibited the highest values compared to the control samples. However, the differences in the examined characteristics among the samples were not statistically significant. Notably, the number of adventitious roots and the forskolin content increased with each increment in IAA hormone concentration. In plants treated with 2 mg L-1 IAA hormone, all measured biometrical traits surpassed those of the control group as well as those of samples co-treated with IAA (2 mg L-1) and ZnO nanoparticles (10 and 20 ppm). The forskolin content followed a similar trend. However, the lowest values for these traits were observed in the plants treated with 2 mg L-1 IAA and 20 ppm ZnO nanoparticles. These findings indicate that 2 mg L-1 of IAA hormone significantly impacts both root morphology and phytochemical characteristics compared to 1 mg L-1. Furthermore, ZnO nanoparticles at a concentration of 20 ppm exhibited an inhibitory effect on root morphology and forskolin content, which could not be mitigated by treatment with 2 mg L-1 IAA.

Coleus forskohlii (Willd.) Briq. is a medicinal herb of the Lamiaceae family. It is native to India and widely present in the tropical and sub-tropical regions of Egypt, China, Ethiopia, and Pakistan. The roots of C. forskohlii are edible, rich with pharmaceutically bioactive compounds, and traditionally reported to treat a variety of diseases, including inflammation, respiratory disorders, obesity, and viral ailments. Notably, the emergence of viral diseases is expected to quickly spread; consequently, these data impose a need for various approaches to develop broad active therapeutics for utilization in the management of future viral infectious outbreaks. In this study, the naturally occurring labdane diterpenoid derivative, Forskolin, was obtained from Coleus forskohlii. Additionally, we evaluated the antiviral potential of Forskolin towards three viruses, namely the herpes simplex viruses 1 and 2 (HSV-1 and HSV-2), hepatitis A virus (HAV), and coxsackievirus B4 (COX-B4). We observed that Forskolin displayed antiviral activity against HAV, COX-B4, HSV-1, and HSV-2 with IC50 values of 62.9, 73.1, 99.0, and 106.0 μg/mL, respectively. Furthermore, we explored the Forskolin's potential antiviral target using PharmMapper, a pharmacophore-based virtual screening platform. Forskolin's modeled structure was analyzed to identify potential protein targets linked to its antiviral activity, with results ranked based on Fit scores. Cathepsin L (PDB ID: 3BC3) emerged as a top-scoring hit, prompting further exploration through molecular docking and MD simulations. Our analysis revealed that Forskolin's binding mode within Cathepsin L's active site, characterized by stable hydrogen bonding and hydrophobic interactions, mirrors that of a co-crystallized inhibitor. These findings, supported by consistent RMSD profiles and similar binding free energies, suggest Forskolin's potential in inhibiting Cathepsin L, highlighting its promise as an antiviral agent. [ABSTRACT FROM AUTHOR]

Coleus forskohlii, an Indian-origin medicinal plant is the sole natural source of the labdane terpenoid forskolin (C22H34O7), with growing demand. Forskolin emerged as an industrially important bioactive compound, with many therapeutic applications in human health. It has established potential effects in the treatment of various diseases and conditions such as glaucoma, asthma, obesity, allergies, skin conditions and cardiovascular diseases. Moreover, clinical trials against different types of cancers are progressing. The mechanism of action of forskolin mainly involves activating adenylyl cyclase and elevating cAMP, thereby regulating different cellular processes. For the extraction of forskolin, tuberous roots of C. forskohlii are used as they contain the highest concentration of this metabolite. Approximately 2500 tonnes of the plant are cultivated annually to produce a yield of 2000–2200 kg ha−1 of dry tubers. The forskolin content of the root is distributed in the range of 0.01–1%, which cannot meet the increasing commercial demands from industries such as pharmaceuticals, cosmetics, dietary supplements, food and beverages. Hence, various aspects of micropropagation with different culture methods that employ precursors or elicitors to improve the forskolin content have been explored. Different extraction and analytical methods are also introduced to examine the yield and purity of forskolin. This review discusses the significance, clinical importance, mechanism of action and different approaches used for mass production including tissue culture for the lead compound forskolin to meet market needs. [ABSTRACT FROM AUTHOR]

Aim: To evaluate and compare the anti-cariogenic efficacy of Coleus forskohlii root extract, cranberry extract and magnetized water as mouthrinses by analysing pH and buffering capacity of saliva and Streptococcus mutans count in 6-12 years old children. Methods: The current study was an in vivo experimental study where 120 children were randomly assigned to four groups of 30 each. Group 1: Coleus forskohlii root extract, Group 2: Cranberry extract, Group 3: Magnetized water, Group 4: Chlorhexidine mouthrinse. Unstimulated saliva was collected and tested for salivary pH, buffering capacity and S. mutans count at 0, 30, 60, and 90 minutes after rinsing and the results were evaluated. Comparison between groups was carried out using one-way ANOVA, independent t test and paired t test. Results: While magnetized water showed the maximum alteration in the salivary pH, Chlorhexidine mouthrinse showed the maximum reduction in the microbial count followed by Coleus forskohlii root extract. All the groups maintained a favourable salivary buffering capacity. Conclusions: Coleus forskohlii root extract, cranberry extract and magnetized water have proven to be effective anti-cariogenic agents and can be used as alternatives to chlorhexidine in improving the oral health with added systemic benefits and minimal side effects.

Coleus forskohlii (Willd.) Briq. is a medicinal herb of the Lamiaceae family. It is native to India and widely present in the tropical and sub-tropical regions of Egypt, China, Ethiopia, and Pakistan. The roots of C. forskohlii are edible, rich with pharmaceutically bioactive compounds, and traditionally reported to treat a variety of diseases, including inflammation, respiratory disorders, obesity, and viral ailments. Notably, the emergence of viral diseases is expected to quickly spread; consequently, these data impose a need for various approaches to develop broad active therapeutics for utilization in the management of future viral infectious outbreaks. In this study, the naturally occurring labdane diterpenoid derivative, Forskolin, was obtained from Coleus forskohlii. Additionally, we evaluated the antiviral potential of Forskolin towards three viruses, namely the herpes simplex viruses 1 and 2 (HSV-1 and HSV-2), hepatitis A virus (HAV), and coxsackievirus B4 (COX-B4). We observed that Forskolin displayed antiviral activity against HAV, COX-B4, HSV-1, and HSV-2 with IC50 values of 62.9, 73.1, 99.0, and 106.0 μg/mL, respectively. Furthermore, we explored the Forskolin’s potential antiviral target using PharmMapper, a pharmacophore-based virtual screening platform. Forskolin’s modeled structure was analyzed to identify potential protein targets linked to its antiviral activity, with results ranked based on Fit scores. Cathepsin L (PDB ID: 3BC3) emerged as a top-scoring hit, prompting further exploration through molecular docking and MD simulations. Our analysis revealed that Forskolin’s binding mode within Cathepsin L’s active site, characterized by stable hydrogen bonding and hydrophobic interactions, mirrors that of a co-crystallized inhibitor. These findings, supported by consistent RMSD profiles and similar binding free energies, suggest Forskolin’s potential in inhibiting Cathepsin L, highlighting its promise as an antiviral agent.

Coleus barbatus is a medicinal herb belonging to Lamiaceae. It is the only living organism known to produce forskolin, which is a labdane diterpene and is reported to activate adenylate cyclase. Microbes associated with plants play an important role in maintaining plant health. Recently, the targeted application of beneficial plant-associated microbes and their combinations in abiotic and biotic stress tolerance has gained momentum. In this work, we carried out the rhizosphere metagenome sequencing of C. barbatus at different developmental stages to understand how rhizosphere microflora are affected by and affect the metabolite content in plants. We found that the Kaistobacter genus was abundantly present in the rhizosphere of C. barbatus and its accumulation pattern appears to correlate with the quantities of forskolin in the roots at different developmental stages. Members of the Phoma genus, known for several pathogenic species, were in lower numbers in the C. barbatus rhizosphere in comparison with C. blumei. To our knowledge, this is the first metagenomic study of the rhizospheric microbiome of C. barbatus, which may help to explore and exploit the culturable and non-culturable microbial diversity present in the rhizosphere. [ABSTRACT FROM AUTHOR]

Introduction: In obese humans, Coleus forskohlii root extract (CF) protects against weight gain owing to the presence of forskolin, an adenylate cyclase (AC) activator. As AC increases intracellular cyclic adenosine monophosphate (cAMP) levels in osteoblasts that has an osteogenic effect, we thus tested the skeletal effects of a standardized CF (CFE) in rats. Methods: Concentrations of forskolin and isoforskolin were measured in CFE by HPLC. CFE and forskolin (the most abundant compound present in CFE) were studied for their osteogenic efficacy in vitro by alkaline phosphatase (ALP), cAMP and cyclic guanosine monophosphate (cGMP) assays. Femur osteotomy model was used to determine the osteogenic dose of CFE. In growing rats, CFE was tested for its osteogenic effect in intact bone. In adult ovariectomized (OVX) rats, we assessed the effect of CFE on bone mass, strength and material. The effect of forskolin was assessed in vivo by measuring the expression of osteogenic genes in the calvarium of rat pups. Results: Forskolin content in CFE was 20.969%. CFE increased osteoblast differentiation and intracellular cAMP and cGMP levels in rat calvarial osteoblasts. At 25 mg/kg (half of human equivalent dose), CFE significantly enhanced calcein deposition at the osteotomy site. In growing rats, CFE promoted modeling-directed bone formation. In OVX rats, CFE maintained bone mass and microarchitecture to the level of sham-operated rats. Moreover, surface-referent bone formation in CFE treated rats was significantly increased over the OVX group and was comparable with the sham group. CFE also increased the pro-collagen type-I N-terminal propeptide: cross-linked C-telopeptide of type-I collagen (PINP : CTX-1) ratio over the OVX rats, and maintained it to the sham level. CFE treatment decreased the OVX-induced increases in the carbonate-to-phosphate, and carbonate-to-amide-I ratios. CFE also prevented the OVX-mediated decrease in mineral crystallinity. Nanoindentation parameters, including modulus and hardness, were decreased by OVX but CFE maintained these to the sham levels. Forskolin stimulated ALP, cAMP and cGMP in vitro and upregulated osteogenic genes in vivo. Conclusion: CFE, likely due to the presence of forskolin displayed a bone-conserving effect via osteogenic and anti-resorptive mechanisms resulting in the maintenance of bone mass, microarchitecture, material, and strength. [ABSTRACT FROM AUTHOR]

IntroductionIn obese humans, Coleus forskohlii root extract (CF) protects against weight gain owing to the presence of forskolin, an adenylate cyclase (AC) activator. As AC increases intracellular cyclic adenosine monophosphate (cAMP) levels in osteoblasts that has an osteogenic effect, we thus tested the skeletal effects of a standardized CF (CFE) in rats.MethodsConcentrations of forskolin and isoforskolin were measured in CFE by HPLC. CFE and forskolin (the most abundant compound present in CFE) were studied for their osteogenic efficacy in vitro by alkaline phosphatase (ALP), cAMP and cyclic guanosine monophosphate (cGMP) assays. Femur osteotomy model was used to determine the osteogenic dose of CFE. In growing rats, CFE was tested for its osteogenic effect in intact bone. In adult ovariectomized (OVX) rats, we assessed the effect of CFE on bone mass, strength and material. The effect of forskolin was assessed in vivo by measuring the expression of osteogenic genes in the calvarium of rat pups.ResultsForskolin content in CFE was 20.969%. CFE increased osteoblast differentiation and intracellular cAMP and cGMP levels in rat calvarial osteoblasts. At 25 mg/kg (half of human equivalent dose), CFE significantly enhanced calcein deposition at the osteotomy site. In growing rats, CFE promoted modeling-directed bone formation. In OVX rats, CFE maintained bone mass and microarchitecture to the level of sham-operated rats. Moreover, surface-referent bone formation in CFE treated rats was significantly increased over the OVX group and was comparable with the sham group. CFE also increased the pro-collagen type-I N-terminal propeptide: cross-linked C-telopeptide of type-I collagen (PINP : CTX-1) ratio over the OVX rats, and maintained it to the sham level. CFE treatment decreased the OVX-induced increases in the carbonate-to-phosphate, and carbonate-to-amide-I ratios. CFE also prevented the OVX-mediated decrease in mineral crystallinity. Nanoindentation parameters, including modulus and hardness, were decreased by OVX but CFE maintained these to the sham levels. Forskolin stimulated ALP, cAMP and cGMP in vitro and upregulated osteogenic genes in vivo.ConclusionCFE, likely due to the presence of forskolin displayed a bone-conserving effect via osteogenic and anti-resorptive mechanisms resulting in the maintenance of bone mass, microarchitecture, material, and strength.

Coronavirus disease 2019 (COVID–19) has spread rapidly as global pandemic affecting 187 countries/ regions and emerged as worldwide health crisis. Potential antiviral drugs used for the SARS -CoV-2 in clinical treatments have side effects. However, emergency vaccines are in use but despite that increase in the coronavirus cases are alarming. Thus, it is utmost need of safer antiviral agent to treat or inhibit the viral infection. Forskolin has been reported as a possible antiviral-agent. This molecule was docked with ACE2 receptor of human which is the target for the binding of S1 unit of viral S protein of SARS-CoV- 2. In silico docking was carried out on SwissDock, PatchDock and FireDock servers. The docked ACE2 structure was further docked with the RBD of the spike protein. Forskolin is able to H-bond with the hACE2 and ACE2-forskolin fails to interact with the receptor-binding domain (RBD) of the Spike protein of SARS-CoV-2. Instead, viral RBD is repulsed by the diterpene molecule through obliteration and reciprocated binding. We report first that forskolin plays a crucial role in the inhibition of protein-protein interaction of RBD and ACE2 when docked with either of the protein.

Coleus barbatus is a medicinal herb belonging to Lamiaceae. It is the only living organism known to produce forskolin, which is a labdane diterpene and is reported to activate adenylate cyclase. Microbes associated with plants play an important role in maintaining plant health. Recently, the targeted application of beneficial plant-associated microbes and their combinations in abiotic and biotic stress tolerance has gained momentum. In this work, we carried out the rhizosphere metagenome sequencing of C. barbatus at different developmental stages to understand how rhizosphere microflora are affected by and affect the metabolite content in plants. We found that the Kaistobacter genus was abundantly present in the rhizosphere of C. barbatus and its accumulation pattern appears to correlate with the quantities of forskolin in the roots at different developmental stages. Members of the Phoma genus, known for several pathogenic species, were in lower numbers in the C. barbatus rhizosphere in comparison with C. blumei. To our knowledge, this is the first metagenomic study of the rhizospheric microbiome of C. barbatus, which may help to explore and exploit the culturable and non-culturable microbial diversity present in the rhizosphere.

The present study was on the analysis of phytochemical constituents of Coleus forskohlii rhizome collected from Thiruvannamalai of Tamil Nadu and testing for its antimicrobial potential against human bacterial pathogens. The dried tubers were extracted using different solvents such as ethanol, aqueous, acetone, chloroform and petroleum ether and screened. The total tannin and saponin content in the extract was estimated. The crude ethanolic solvent extract of C. forskohlii was tested for its antimicrobial activity using disc diffusion method. Phytochemical screening of the crude solvent extracts revealed the presence of tannins, phenols, saponins, quinone, flavonoids, cardiac glycoside, terpenoids, steroids, alkaloids, and coumarins. Tannic acid was found in the level of 53.47 ±0.37 mg TAE/g. Saponin content was 2.42±0.63 mg/g dry weight. The crude ethanolic rhizome extract was tested in three different concentrations (10, 20 and 30mg/ml). Maximum antibacterial activity was noted against Bacillus subtilis (15 mm), followed by Bacillus cereus (14 mm), P. aeruginosa (12 mm) and S. aureus (12mm). E. coli was not inhibited even at the highest concentration tested (i.e.) 30mg/ml. The minimum inhibitory concentration (MIC) values of the pathogens tested were 1.4±0.02, 1.590±0.02, 1.820±0.02 and 2.350±0.02 mg/ml respectively to B. subtilis, B. cereus, P. aeruginosa , and S. aureus. Similarly, the minimum bactericidal concentration (MBC) for B. subtilis, B. cereus, P. aeruginosa , and S. aureus were respectively of 2.89±0.02, 3.833±0.05, 3.842±0.01 and 4.856±0.05 mg/ml. In time-kill assay 3 Log reduction was found to be around 11 h for B. subtilis, around 12 h for B. cereus for P. aeruginosa around 13 h and above 14 and less than 15 h for S. aureus. The study showed the antimicrobial potential of ethanol extract of C. forskohlii tuber against human bacterial pathogens and hence it seems to be useful in the preparation of drug formulations.

Coronavirus disease 2019 (COVID-19) has spread rapidly as global pandemic affecting 187 countries/regions and emerged as worldwide health crisis. Potential antiviral drugs used for the SARS-CoV-2 in clinical treatments have side effects. However, emergency vaccines are in use but despite that increase in the coronavirus cases are alarming. Thus, it is utmost need of safer antiviral agent to treat or inhibit the viral infection. Forskolin has been reported as a possible antiviral-agent. This molecule was docked with ACE2 receptor of human which is the target for the binding of S1 unit of viral S protein of SARSCoV-2. In silico docking was carried out on SwissDock, PatchDock and FireDock servers. The docked ACE2 structure was further docked with the RBD of the spike protein. Forskolin is able to H-bond with the hACE2 and ACE2-forskolin fails to interact with the receptor-binding domain (RBD) of the Spike protein of SARS-CoV-2. Instead, viral RBD is repulsed by the diterpene molecule through obliteration and reciprocated binding. We report first that forskolin plays a crucial role in the inhibition of proteinprotein interaction of RBD and ACE2 when docked with either of the protein. [ABSTRACT FROM AUTHOR]

Background: Patients taking multiple drugs and various health foods often develop acute hepatitis. We hypothesized that the interaction between health foods and drug metabolism was the cause of severe liver injury in these patients. Therefore, we studied changes in the activity of the drug-metabolizing enzyme, cytochrome P450 (CYP), using slimming health food extracts and elucidated the molecular mechanism of liver injury onset through hepatotoxicity evaluation., Methods: For cytotoxicity testing, health food extract samples were added to HepG2 cells derived from hepatic parenchymal cells and culture medium, and cell viability was calculated 48 h after culture. To evaluate CYP3A4 induction, 3-1-10 cells constructed with a reporter linked to CYP3A4 gene were used, and reporter activity was measured 48 h after culture., Results: In the chronological order of the slimming health food intake history of the patient, niacinamide and Gymnema sylvestre extracts strongly inhibited HepG2 cell viability. In contrast, dietary supplements A and Coleus forskohlii extract strongly induced CYP3A4 reporter activity., To confirm CYP3A4 induction in humans, humanized CYP3A/pregnane X receptor (PXR) mice were treated with forskolin. CYP3A4 mRNA expression levels were elevated 3.9 times compared to that of the control group ( P < 0.05)., Conclusion: Coleus forskohlii extract showed the strongest transcriptional activation of CYP3A4 gene. In a mouse model of human-type drug metabolism, forskolin induced CYP3A4 transcription. Thus, we concluded that CYP3A4 induction by Coleus forskohlii is one of the causes of crucial hepatocellular injury, which is a type of liver injury caused by the active metabolite of acetaminophen produced by CYP3A4., Competing Interests: The authors declare no conflict of interest., (©2024 Tottori University Medical Press.)

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.

Coleus forskohlii roots are mainly used for extraction of the bioactive diterpenoid, forskolin, which has enormous biological activities. In this study, impact of the solvent and extraction method on forskolin content from Coleus forskohlii root powder was investigated. Nine solvents from different polarity group were tested for forskolin extraction. It was found that the efficiency of the solvents used to extract forskolin varied considerably (0.18 to 2.91 %). The average values indicated that among all the extractives, forskolin content was significantly higher in methanol (2.91 %), followed by ethanol (2.59 %), and least content was found in water (0.18 %). Low polarity solvents were not found very effective for forskolin extraction. Further three different extraction methods (Soxhlet/refluxing, ultrasound and microwaveassisted solvent extraction) were also compared using safest and most effective solvent for forskolin yield. As ethanol exhibited good extraction efficiency for forskolin and is a safe solvent, it was chosen for further optimization of extraction method. Soxhlet extraction technique gave higher yield of forskolin (0.17 to 2.83 %) compared to microwave-assisted solvent extraction (0.09 to 2.29 %) and ultra sound-assisted extraction (0.08 to 1.47 %). From these results it was evident that the extraction of forskolin depended on extraction process as well as the solvent useds. [ABSTRACT FROM AUTHOR]

Coleus (Lamiaceae) is a large and widespread genus comprising of species with diverse ethnobotanical uses. In the present study, bacterial endophytes were isolated from Coleus forskohlii and Coleus aromaticus. Endophytes are the microorganisms which reside within the plants without showing any harmful effect on its host. Diverse types of endophytes live symbiotically within almost all plants and in turn help the plant in a number of ways such as imparting resistance against biotic and abiotic stresses, producing compounds involved in attraction of pollinators, inducing the plant defense mechanisms, etc. The bacterial endophytes isolated in this study, were characterized by microscopic examination (using gram staining) and molecularly identified by sequencing the 16S rRNA. Extracts were prepared from endophytic biomass using solvents of different polarities (methanol, ethyl acetate and butanol) and were screened for their bioactive potential (in vitro cytotoxicity anti-microbial, and anti-oxidant activity). Scale-up of endophytes showing promising results is under process, which will help in isolation of pure compounds. [ABSTRACT FROM AUTHOR]

Forskolin is mainly found in the root of a plant called Coleus forskohlii (Willd.) Briq., which has been used in the traditional medicine of Indian Ayurvedic and Southeast Asia since ancient times. Forskolin is responsible for the pharmacological activity of this species. Forskolin is a labdane diterpenoid with a wide biological effect. Several studies suggested a positive role of forskolin on heart complications, respiratory disorders, high blood pressure, obesity, and asthma. There are numerous clinical and pre-clinical studies representing the effect of forskolin on the above-mentioned disorders but more clinical studies need to be performed to support its efficacy. [ABSTRACT FROM AUTHOR]

The present study was on the analysis of phytochemical constituents of Coleus forskohlii rhizome collected from Thiruvannamalai of Tamil Nadu and testing for its antimicrobial potential against human bacterial pathogens. The dried tubers were extracted using different solvents such as ethanol, aqueous, acetone, chloroform and petroleum ether and screened. The total tannin and saponin content in the extract was estimated. The crude ethanolic solvent extract of C. forskohlii was tested for its antimicrobial activity using disc diffusion method. Phytochemical screening of the crude solvent extracts revealed the presence of tannins, phenols, saponins, quinone, flavonoids, cardiac glycoside, terpenoids, steroids, alkaloids, and coumarins. Tannic acid was found in the level of 53.47 ±0.37 mg TAE/g. Saponin content was 2.42±0.63 mg/g dry weight. The crude ethanolic rhizome extract was tested in three different concentrations (10, 20 and 30mg/ml). Maximum antibacterial activity was noted against Bacillus subtilis (15 mm), followed by Bacillus cereus (14 mm), P. aeruginosa (12 mm) and S. aureus (12mm). E. coli was not inhibited even at the highest concentration tested (i.e.) 30mg/ml. The minimum inhibitory concentration (MIC) values of the pathogens tested were 1.4±0.02, 1.590±0.02, 1.820±0.02 and 2.350±0.02 mg/ml respectively to B. subtilis, B. cereus, P. aeruginosa, and S. aureus. Similarly, the minimum bactericidal concentration (MBC) for B. subtilis, B. cereus, P. aeruginosa, and S. aureus were respectively of 2.89±0.02, 3.833±0.05, 3.842±0.01 and 4.856±0.05 mg/ml. In time-kill assay 3 Log reduction was found to be around 11 h for B. subtilis, around 12 h for B. cereus for P. aeruginosa around 13 h and above 14 and less than 15 h for S. aureus. The study showed the antimicrobial potential of ethanol extract of C. forskohlii tuber against human bacterial pathogens and hence it seems to be useful in the preparation of drug formulations. [ABSTRACT FROM AUTHOR]

Coleus forskohlii Briq. has been used traditionally for the treatment of several ailments since antiquity in Ayurveda. In the present study, an approach has been made to evaluate the effect of C. forskohlii and its major constituents on cytochrome P450 (CYP3A, CYP2B, and CYP2C) mRNA expression in rat hepatocytes. To gain better understanding of the herb–drug interaction potential of the chemical constituents present in C. forskohlii, the extract was subjected to column chromatography followed by standardization with respect to forskolin, 1-deoxyforskolin, and 1,9-dideoxyforskolin using reversed-phase high-performance liquid chromatography (RP-HPLC). Hepatocytes were treated with extracts, fractions, and phytoconstituents, followed by extraction and purification of total mRNA. Study of mRNA expression was carried out through reverse transcription polymerase chain reaction, followed by agarose gel electrophoresis. Results revealed that the test substances did not show any significant mRNA expression compared to the control against CYP3A, CYP2B, and CYP2C. Positive controls such as dexamethasone and rifampin showed significantly high (p

The herbal compositions of Coleus forskohlii, Salacia reticulata, and Sesamum indicum, standardized for forskolin, mangiferin, and sesamin, respectively, were shown, in vitro, to inhibit pancreatic lipase with differing degrees and dynamics. In the placebo controlled six weeks clinical study the daily intake of 1000 mg C. forskohlii stand-alone standardized for 10% forskolin, showed statistically significant lowering of total body fat vs. baseline and placebo group (p

The herbal composition of Coleus forskohlii, Salacia reticulata, and Sesamum indicum, standardized for forskolin, mangiferin, and sesamin, respectively, were shown, in vitro, to inhibit pancreatic lipase with differing degrees and dynamics. In the placebo controlled six weeks clinical study the daily intake of 1000 mg C. forskohlii stand-alone standardized for 10% forskolin, showed statistically significant lowering of total body fat vs. baseline and placebo group (p

Objective: Current trend of commercialization of herbal medicines draw a huge need of maintaining their quality. The declaration of quality, safety and efficacy of medicinal plants as well as poly-herbal formulations has become an important issue. Hence, qualitative and quantitative analysis of herbal drugs and formulations viz., fingerprint profiles and quantification of the various markers become key factors of quality control. Materials and Methods: Present investigation is a detailed report for quality control of well-known herb Coleus forskohlii Briq, which includes physicochemical parameter determination, safety evaluation, microscropical evaluation, and chromatographic fingerprinting as well. Results: Physico-chemical characters were evaluated according to Indian Pharmacopoeia, further microscopic evaluation of transverse section of Coleus reveals that periderm, secondary phloem, and wide secondary xylem cylinder, which occupies major portion of the root fragmentary. Chromatographic fingerprint profiles of Coleus have been generated, and a marker based standardization strategy was adopted; using different analytical technique like high-performance thin layer chromatography, high-performance liquid chromatography and gas chromatography-mass spectroscopy to maintain quality and ensure safety as well as efficacy. Conclusion: These advancements in modern techniques of analysis can lead to effective quality control of Coleus as well as other herbs. Present report can act as pioneer for quality control of modern herbal medicine.

Ultraviolet (UV)-B radiation and the growth hormone indole-3-acetic acid (IAA) have been known to cause various changes in plants at morphological and physiological levels as individual entities, but their interactive effects on the overall plant performance remain practically unknown. The present study was conducted under near-natural field conditions to evaluate the effects of supplemental (s)-UV-B (ambient+3.6 kJ m −2 day −1 ) treatment alone, and in combination with two doses of IAA (200 ppm and 400 ppm) exogenously applied as foliar spray on various growth-, morphological-, physiological-, and biochemical parameters of an indigenous medicinal plant, Coleus forskohlii . Under s-UV-B, the plant growth and morphology were adversely affected (along with reductions in protein- and chlorophyll contents) with concomitant increase in secondary metabolites (as substantiated by an increase in the activities of various enzymes of the phenylpropanoid pathway) and cumulative antioxidative potential (CAP), suggesting the plant's capability of adaptive resilience against UV-B. The essential oil content of the plant was, however, compromised reducing its pharmaceutical value. IAA application at both doses led to a reversal in the effects caused by s-UV-B radiation alone; both the plant growth as well as the essential oil content improved, especially at the higher IAA dose, suggesting its ameliorative role against UV-B induced oxidative stress, and also in improving the plant's medicinal value. [ABSTRACT FROM AUTHOR]

Forskolin is a unique structurally complex labdane-type diterpenoid used in the treatment of glaucoma and heart failure based on its activity as a cyclic AMP booster. Commercial production of forskolin relies exclusively on extraction from its only known natural source, the plant Coleus forskohlii, in which forskolin accumulates in the root cork. Here, we report the discovery of five cytochrome P450s and two acetyltransferases which catalyze a cascade of reactions converting the forskolin precursor 13R-manoyl oxide into forskolin and a diverse array of additional labdane-type diterpenoids. A minimal set of three P450s in combination with a single acetyl transferase was identified that catalyzes the conversion of 13R-manoyl oxide into forskolin as demonstrated by transient expression in Nicotiana benthamiana. The entire pathway for forskolin production from glucose encompassing expression of nine genes was stably integrated into Saccharomyces cerevisiae and afforded forskolin titers of 40 mg/L.

Coleus forskohlii extract (CFE), an herbal ingredient, is used for weight-loss products. CFE's alleged efficacy is attributed to forskolin. However, CFE has been shown to induce fatty liver in mice, with components other than forskolin playing a part in this effect. The present study addressed the underlying mechanism of CFE-induced fatty liver by analyzing changes in CFE-treated mice of lipid concentrations and of the levels of mRNAs encoding enzymes and transcription factors known to be related to fatty liver. Mice were fed a diet containing 0, 0.3 and 1% CFE for 2 weeks. CFE at 1% clearly induced fatty liver, as demonstrated by histological examination and confirmed by increases in triglyceride concentrations in liver. However, treated mice did not exhibit elevation in plasma levels of non-esterified fatty acids. Comprehensive analysis of liver mRNA levels revealed accumulation of multiple transcripts, including mRNAs encoding enzymes acetyl-CoA carboxylase and long-chain elongase; transcription factor peroxisome proliferator-activated receptor gamma (PPARγ); and lipid-droplet-associated fat-specific protein 27 (Fsp27). These findings suggest that the de novo synthesis and accumulation of triglyceride in the liver, through the enhanced expression of specific lipogenic mRNAs, is a major underlying mechanism of fatty liver induction by CFE.

Forskolin is mainly found in the root of a plant called Coleus forskohlii (Willd.) Briq., which has been used in the traditional medicine of Indian Ayurvedic and Southeast Asia since ancient times. Forskolin is responsible for the pharmacological activity of this species. Forskolin is a labdane diterpenoid with a wide biological effect. Several studies suggested a positive role of forskolin on heart complications, respiratory disorders, high blood pressure, obesity, and asthma. There are numerous clinical and pre-clinical studies representing the effect of forskolin on the above-mentioned disorders but more clinical studies need to be performed to support its efficacy.

Background: Coleus forskohlii is a well-known industrially important medicinal plant, for its high forskolin content. Objective: A simple, selective, and sensitive high-performance thin layer chromatography (HPTLC) method was developed and validated for simultaneous quantification of forskolin and iso-forskolin in C. forskohlii germplasm collected from the Eastern Ghats, India. Materials and Methods: Chromatographic separation of the targeted marker(s) was obtained on precoated silica plates using toluene: ethyl acetate: methanol (90:30:0.5, v/v/v) as the mobile phase. Results: Densitometric quantification of forskolin and iso-forskolin was carried out at 545 nm. Forskolin and iso-forskolin were identified by comparing the ultraviolet spectra of standard and sample track at Rfof 0.64 ± 0.02 and 0.36 ± 0.01, after derivatization with anisaldehyde sulfuric acid reagent. The linearity of both the analytes was obtained in the range of 300–1200 ng/spot with the regression coefficient (R2) of 0.991 and 0.986. Recovery of analyte (s) at three levels, namely, 100, 150, and 200 ng/spot was found to be 100.46% ± 0.29%, 99.64% ± 0.33%, 100.02% ± 0.76% and 99.76% ± 0.62%, 99.56% ± 0.35%, 100.02% ± 0.22%, respectively, for forskolin and iso-forskolin. The content of forskolin and iso-forskolin varies from 0.046% to 0.187% and 0.002% to 0.077%, respectively (dry weight basis), the maximum content of both the markers was found in NBC-31, from Thakurwada, Maharashtra. Conclusion: The developed HPTLC method was linear, accurate, and reliable as per the International Council for Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use guidelines. The study aids in the identification of elite chemotype for commercial prospection of industrially viable medicinal crop. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the phytochemical constituents, gas chromatography-mass spectrometry (GC-MS) analysis and antimicrobial activity of Coleus forskohlii. The different solvents such as ethanol, chloroform, acetone and aqueous extracts were identified pharmacologically as important bioactive compounds and their antimicrobial properties were studied. In the phytochemical investigation almost all the ethanol extract of leaf, stem and root having secondary metabolites like alkaloids, flavonoids, tannins, saponins, terpenoids, and steroids. The active constituents of the ethanol extract of C. forskohlii root was studied by GC-MS analysis. According to the antimicrobial results ethanol extract of C. froshkolii root showed highest antibacterial activity compared with stem and leaf. The highest antimicrobial activity was observed against Klebsiella pneumonia (19 mm) and Candida albicans (16 mm) in ethanol extract of root. Among the above extracts of leaf, stem and root, ethanol extract of root having antimicrobial activities due to the presence of phytoconstituents.

Introduction: In obese humans, Coleus forskohlii root extract (CF) protects against weight gain owing to the presence of forskolin, an adenylate cyclase (AC) activator. As AC increases intracellular cyclic adenosine monophosphate (cAMP) levels in osteoblasts that has an osteogenic effect, we thus tested the skeletal effects of a standardized CF (CFE) in rats., Methods: Concentrations of forskolin and isoforskolin were measured in CFE by HPLC. CFE and forskolin (the most abundant compound present in CFE) were studied for their osteogenic efficacy in vitro by alkaline phosphatase (ALP), cAMP and cyclic guanosine monophosphate (cGMP) assays. Femur osteotomy model was used to determine the osteogenic dose of CFE. In growing rats, CFE was tested for its osteogenic effect in intact bone. In adult ovariectomized (OVX) rats, we assessed the effect of CFE on bone mass, strength and material. The effect of forskolin was assessed in vivo by measuring the expression of osteogenic genes in the calvarium of rat pups., Results: Forskolin content in CFE was 20.969%. CFE increased osteoblast differentiation and intracellular cAMP and cGMP levels in rat calvarial osteoblasts. At 25 mg/kg (half of human equivalent dose), CFE significantly enhanced calcein deposition at the osteotomy site. In growing rats, CFE promoted modeling-directed bone formation. In OVX rats, CFE maintained bone mass and microarchitecture to the level of sham-operated rats. Moreover, surface-referent bone formation in CFE treated rats was significantly increased over the OVX group and was comparable with the sham group. CFE also increased the pro-collagen type-I N-terminal propeptide: cross-linked C-telopeptide of type-I collagen (PINP : CTX-1) ratio over the OVX rats, and maintained it to the sham level. CFE treatment decreased the OVX-induced increases in the carbonate-to-phosphate, and carbonate-to-amide-I ratios. CFE also prevented the OVX-mediated decrease in mineral crystallinity. Nanoindentation parameters, including modulus and hardness, were decreased by OVX but CFE maintained these to the sham levels. Forskolin stimulated ALP, cAMP and cGMP in vitro and upregulated osteogenic genes in vivo ., Conclusion: CFE, likely due to the presence of forskolin displayed a bone-conserving effect via osteogenic and anti-resorptive mechanisms resulting in the maintenance of bone mass, microarchitecture, material, and strength., Competing Interests: Authors AG and LH were employed by Pharmanza Herbal Pvt. Ltd. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Kulkarni, Sharma, Porwal, Rajput, Sadhukhan, Singh, Singh, Baranwal, Kumar, Girme, Pandey, Singh, Sashidhara, Kumar, Hingorani and Chattopadhyay.)

Limited studies have shown that Coleus forskohlii extract may aid in weight management. This randomized, double blind placebo-controlled clinical study assessed the effects of supplementation with C. forskohlii extract on key markers of obesity and metabolic parameters in overweight and obese individuals. Thirty participants completed the trial and they were randomly assigned to receive either 250 mg of C. forskohlii extract (n = 15) or a placebo twice daily for 12 weeks. All participants were advised to follow a hypocaloric diet throughout the study. Body weight, body mass index (BMI), waist and hip circumference, and waist to hip ratio, were monitored fortnightly. Dietary intake was assessed at the baseline and weeks 4, 8 and 12. Appetite was assessed using visual analogue scales and blood samples were analyzed for plasma lipids, ghrelin, leptin, glucose and insulin at the baseline and end of the intervention. Significant reductions to waist and hip circumference (p = 0.02; p = 0.01, respectively) were recorded in both experimental and placebo groups after the 12 week intervention. Furthermore, high density lipoprotein-cholesterol (HDL-C) was significantly increased (p = 0.01) in both groups. The experimental group showed a favorable improvement in insulin concentration and insulin resistance (p = 0.001; 0.01 respectively) compared to the placebo group. These findings suggest that C. forskohlii extract in conjunction with a hypocaloric diet may be useful in the management of metabolic risk factors. [ABSTRACT FROM AUTHOR]

Objective: Current trend of commercialization of herbal medicines draw a huge need of maintaining their quality. The declaration of quality, safety and efficacy of medicinal plants as well as poly-herbal formulations has become an important issue. Hence, qualitative and quantitative analysis of herbal drugs and formulations viz., fingerprint profiles and quantification of the various markers become key factors of quality control. Materials and Methods: Present investigation is a detailed report for quality control of well-known herb Coleus forskohlii Briq, which includes physicochemical parameter determination, safety evaluation, microscropical evaluation, and chromatographic fingerprinting as well. Results: Physico-chemical characters were evaluated according to Indian Pharmacopoeia, further microscopic evaluation of transverse section of Coleus reveals that periderm, secondary phloem, and wide secondary xylem cylinder, which occupies major portion of the root fragmentary. Chromatographic fingerprint profiles of Coleus have been generated, and a marker based standardization strategy was adopted; using different analytical technique like high-performance thin layer chromatography, high-performance liquid chromatography and gas chromatography-mass spectroscopy to maintain quality and ensure safety as well as efficacy. Conclusion: These advancements in modern techniques of analysis can lead to effective quality control of Coleus as well as other herbs. Present report can act as pioneer for quality control of modern herbal medicine. [ABSTRACT FROM AUTHOR]

Background: Coleus forskohlii Willd. is a popular traditional medicine used since ancient times for treatment of heart diseases, abdominal colic and respiratory disorders. Objective: The aim of this study was to characterize the root extract of the medicinal plant Coleus forskohlii. Materials and Methods: Dry roots of C. forskohlii were used to extract Forskolin using toluene as a solvent. Thus, obtained extract of C. forskohlii was standardized to 30% and used for further studies. Results: The physical properties of the extract were analyzed through scanning electron microscopy analysis, while the characterization of root extract through X-ray diffraction (XRD) and element analysis. The morphological feature of the C. forskohlii extract showed a flake like structure and the XRD showed sulfur trioxide (SO3) and trimer of sulfur trioxide (S3O9). Through element analysis, elements such as carbon, oxygen, magnesium, aluminum, silicon, phosphorous, and sulfur were identified. Carbon showed the highest weight of 75.49% in comparison to all other elements. [ABSTRACT FROM AUTHOR]

Coleus forskohlii Briq. (Family: Lamiaceae) is a fleshy perennial aromatic herb with fibrous roots that grows under tropical to temperate areas in India, Burma, Thailand, Nepal, Pakistan, Sri Lanka, East Africa and Brazil. The rootstock of the plant is used in Ayurveda and other systems of medicine for several ailments such as heart and lung conditions, asthma, digestive disorder, insomnia, muscle spasm, convulsion and skin diseases. Extensive literature survey was performed based on distribution, morphology, phytochemistry and pharmacological aspects of C. forskohlii through pubmed, scopus, SciFinder, google scholar, sciencedirect and ethnobotanical books. Phytopharmacological knowledge and cosmeceutical use of C. forskohlii and its bioactive constituents have been documented. Coleus roots are exclusive source of forskolin, commonly known as fat burning molecule. It's unique property is activating of almost all hormone sensitive adenylate cyclase enzymes by cyclic 3′,5′-adenosine monophosphate (cAMP). Other potent compounds are 9-deoxyforskolin ( 1), 1,9-dideoxyforskolin ( 2), forskolin I ( 7), forskolin J ( 8), forskolin L ( 9), isoforskolin ( 16), 1-acetylforskolin ( 17), forskoditerpenoside A ( 19), forskoditerpenoside B ( 20), coleol ( 21), coleosol ( 22), 3-hydroxyforskolin ( 25) etc. Besides well established food and traditional use, clinical evidence indicates its safety assessment and can be taken without any toxic effect. This review covers up to date ethnopharmacological, phytochemical and phytomedical information of C. forskohlii approaching towards its safety and therapeutic perspective. [ABSTRACT FROM AUTHOR]

Background: Obesity is a metabolic disorder that can lead to adverse metabolic effects on blood pressure, cholesterol, triglycerides and insulin resistance and also increases the risk of coronary heart disease, ischemic stroke and type 2 diabetes mellitus. This study was designed to determine the effect of Coleus forskohlii on obesity and associated metabolic changes in rats fed with cafeteria diet. Objective: The aim of this study was to evaluate antiobesogenic and metabolic benefits of C. forskohlii in cafeteria diet induced obesity rat model. Materials and Methods: Rats were randomly divided into five groups of six animals in each group and as follows: Normal pellet diet group; cafeteria diet group; cafeteria diet followed by 50 mg/kg/d Coleus forskohlii extract (CFE), 100 mg/kg/d CFE and 45 mg/kg/d orlistat groups, respectively. Indicators of obesity such as food intake, body weight and alteration in serum lipid profiles were studied. Results: Feeding of cafeteria diet induced obesity in rats. Administration of CFE significantly halted increase in food intake and weight gain associated with cafeteria diet. Development of dyslipidemia was also significantly inhibited. Conclusion: The observed effects validate that supplementation of CFE with cafeteria diet could curb the appetite and mitigate the development of dyslipidemia. [ABSTRACT FROM AUTHOR]

This study was taken up to determine the combined effect of arbuscular mycorrhizal (AM) fungi and plant growth promoting rhizobacteria (PGPR) in controlling root rot caused by Macrophomina phaseolina in Coleus forskohlii. AM root colonization was up to 70-73 per cent under combined inoculation of Scutellospora sp + Pseudomonas fluorescens + Trichoderma viride and 44-45 per cent under individual inoculation. A correlation analysis indicated that more the AM root colonization (73 per cent) less the root rot (28 per cent) incidence. The activity of the defense enzymes viz., peroxidase, polyphenol oxidase and superoxide dismutase was found to be high at 30 days after inoculation of the pathogen in the co-inoculated treatments. Another correlation study between AM colonization and enzyme activity, showed low root rot index. There was a loss in the alkaloid content due to pathogen infection, yet, the combined treatments recorded a threefold increase in disease suppression. [ABSTRACT FROM AUTHOR]

Coleus forskohlii Briq. is an indigenous medicinal plant with high traditional use in India. Genetic analysis of 37 diverse C. forskohlii genotypes was performed using 25 RAPD primers, which yielded 117 bands, of which 60 (51.28%) were polymorphic providing an average of 3.75 bands per primer. There were no genotype-specific products. The number of bands per primer varied from 1 (OPZ 8&16) to 7 (OPZ 11). Similarity matrix was constructed using Jaccard's Coefficient and the data matrix of coefficient of similarity was subjected to cluster analysis using unweighted pair group methodology with arithmetic average (UPGMA). Cluster analysis resulted in grouping of 37 genotypes into two major clusters. The results indicated that RAPD could be used for genetic diversity analysis in C. forskohlii using higher number of primers as it is reliable, easy, rapid and cost-effective.

The present investigation was carried out during 2003-2007 involving terminal cuttings of coleus ecotype 'Garmai'. Genotypic correlation coefficient between yield and its components in mutants of coleus was studied, viz., plant height, number of branches plant-1, number of leaves plant-1, number of tubers plant-1, tuber length and tuber girth were found to have positive and highly significant correlation with yield. However, forskolin and essential oil content showed negative correlation with yield. Path analysis of component characters on yield of Coleus in V2M1 generation exerted positive direct effect through the characters plant height, number of leaves plant-1 and number of tubers plant-1. Similarly, direct effect was observed to be negative through number of branches plant-1 (-0.930), total amount of alkaloids (-0.066) and forskolin content (-0.026). The current investigation resulted in residual effect of 0.158 indicating the accuracy and appropriate selection of component character for crop improvement programme. Weightage must be given to component characters exhibiting positive attributes towards fresh tuber yield in Coleus. However, some traits with negative attributes are also chosen for getting improved quality, i.e., forskolin content, without much inhibition on fresh tuber yield plant-1.

Thirty seven Coleus forskohlii genotypes collected from different regions of Tamil Nadu and Karnataka were subjected to diversity analysis based on NBPGR descriptors. Eleven qualitative and fourteen quantitative traits of C. forskohlii were evaluated to assess the morphological variations available among the collected genotypes. For qualitative traits, a large number of genotypes out of 37 clustered together at 74 % similarity in four different groups. The dendrogram contract based on fourteen quantitative traits for the same set of genotypes did not reveal a clear pattern in grouping and the genotypes were grouped into ten different clusters. Cluster analysis of various sets of data revealed different groups of genotypes for each of the data set. A poor congruence observed among data sets of qualitative and quantitative traits in the comparison indicated that the morphological traits are not suitable for precise discrimination of closely related genotypes in C. forskohlii.

Plectranthus barbatus (syn . Coleus forskohlii) is the only known source of forskolin, a compound with a wide range of pharmacological activities. Here, an efficient protocol for adventitious root regeneration from leaf explants of P. barbatus was developed. Different concentrations of plant growth regulators individually and in combination were used to induce roots in vitro. Morphogenic responses and forskolin production varied depending on the concentrations of plant growth regulators added to the medium. Lower concentrations of auxins trigger callus proliferation while higher concentrations induced adventitious root regeneration. Of all the auxins, 2,4-dichlorophenoxyacetic acid (2,4-D), 2,4,5-trichlorophenoxyacetic acid (2,4,5-T), 2 (2,4,5-trichlorophenoxy) propionic acid (2,4,5-TP), and 4-amino-3,5,6-trichloropicolinic acid (picloram) induced callus, whereas α-naphthaleneacetic acid (NAA), indole-3-acetic acid, and indole-3-butyric acid induced rhizogenesis. Use of picloram at 1.0 and 0.5 mg l resulted in the formation of friable callus, and when combined with 0.5 mg l 6-benzylamino purine (BA), rhizogenic callus was produced. The cytokinins BA and kinetin produced a mixed response of multiple shoot regeneration, callus proliferation, and rhizogenesis. The maximum forskolin content of 1,178 mg kg dry weight was found in root cultures initiated on Gamborg's B medium supplemented with 0.5 mg l NAA. The biosynthesis of forskolin was differentiation dependent, and rhizogenic cultures exhibited the maximum biosynthetic potential for forskolin. [ABSTRACT FROM AUTHOR]