Conventional propagation of Euphorbia pulcherrima Willd is limited by low efficiency and long timelines, creating a need for improved in vitro regeneration strategies. In vitro direct adventitious shoot organogenesis is mediated by wounding and exogenous application of Plant Growth Regulators (PGRs), specifically, auxins and cytokinins, which facilitates the redifferentiation of somatic cells and development of new shoots, and thus has the potential to increase regeneration efficiency. This study systematically investigated the effects of silver nitrate (AgNO3) and myo-inositol as growth adjuvants on in vitro regeneration of Euphorbia pulcherrima cv. Christmas Eve. Quantitative assessments of various concentrations revealed that these growth adjuvants significantly enhanced morphogenic potential. This phenotypic enhancement correlated with the transcriptional upregulation of key shoot regeneration regulatory genes and downregulation of ethylene biosynthesis genes, particularly under AgNO3 treatment. Collectively, these findings suggest that the modulation of endogenous hormonal homeostasis driven by the expression or suppression of specific transcription factors serves as a primary determinant of cellular totipotency and subsequent cell fate transitions.
The production of valuable bioactive compounds in the medicinal plant Glycyrrhiza glabra L. (G. glabra) would benefit from biotechnological approaches for the cultivation and induction of metabolite-producing hairy roots. Germination trials were tested to overcome seed dormancy, achieving high germination rates with sulfuric acid treatment. Hairy root cultures of cotyledons using Rhizobium rhizogenes strain 1724 showed the highest transformation efficiency. A fast-growing line, line S, was subsequently exposed to light treatments (red, blue, and blue and red combined) to evaluate their effects on growth, phenolic content, and Ferric Reducing Antioxidant Power (FRAP). Hairy root cultures grown in blue light and in blue and red light combined had higher growth rates than those grown in red light only or in control conditions (dark). FRAP increased over time under all light treatments, including the control, and those cultures exposed to blue and red light combined had higher FRAP than the control. These findings provide valuable insights into conditions for optimal seed germination and hairy root transformation. Treatment of the line S with different qualities of light induced changes in antioxidant capacity and phenolic content, indicating promise for its use in upregulating secondary metabolite production in G. glabra for future biotechnological applications.
Pulsed electric field (PEF) and high-pressure processing (HPP) are non-thermal treatments, developed to ensure preservation of food products whilst maintaining taste and valuable nutrients. In this study, we investigated their potential for the inactivation of 3 commercial exogenous pectinases (polygalacturonase, pectin transeliminase, pectin esterase) commonly used in juice processing for clarification of juices. The inactivation of these enzymes after processing is mandatory by European law. Clear apple juice was treated with both non-thermal processing methods, as well as with thermal pasteurization as the standard method. For HPP, 3 pressures (250, 450, and 600 MPa) and different holding times (from 2 to 12 min) were tested. For PEF, 3 electric field intensities (10, 13, and 15 kV/cm) and different specific energy values (from 121 to 417 kJ/kg). Standard thermal pasteurization resulted in a complete inactivation of all tested pectinases. HPP treatment only showed marginal effects on polygalacturonase and pectin transeliminase at the highest pressure and holding times, which are beyond levels used in industrial settings. For PEF, dependence upon high electric field strength and specific energy values was evident; however, here too, the effect was only moderate at the levels attainable within the scope of this study. Assuming a continued linear relationship, usable results could be achieved in an industrial setting, albeit under more extreme conditions.
The browning of fruit juices and nectars is a common issue in the beverage industry and is a particular problem in strawberry nectars, where it significantly reduces the shelf-life. Polyphenol oxidases (PPOs), which are multicopper enzymes responsible for the oxidation of a wide plethora of polyphenols in plants, have been widely assumed to be involved in the enzymatic browning of strawberry nectar. To investigate the possible involvement of PPOs, the substrate specificity of four recombinant PPOs and their gene expression pattern in 10 cultivars of Fragaria × ananassa at five ripening stages were determined. This allowed us to obtain adequate amounts of enzymes to study them independently and without interfering matrix effects. All four PPOs possess monophenolase activity, which was particularly high for PPO4. PPO3 did not show sufficient stability for the kinetic studies. The other three showed a high preference for the flavan 3-ol catechin with a 2-fold higher catalytic efficiency compared to dopamine for PPO1 and PPO2. At a neutral pH, they also showed activity with cyanidin but not with pelargonidin, which is the prevalent anthocyanidin type in strawberry. The enzymes showed a high affinity but only low turnover rates for the dihydrochalcone phloretin, resulting in an inhibitory effect that was strong enough to extend the shelf-life of the strawberry nectar by one week if phloretin was added in high concentrations (600 µM). PPO1 and PPO2 were prevalently expressed in all fruit stages. The gene expression of the four PPOs did not correlate with the color stability of the nectars of the 10 varieties and also showed a random expression pattern during fruit development. The limited activity in acidic conditions and the low substrate specificity for pelargonidin does not point to a crucial role for PPOs in the browning of strawberry nectar, but the high catalytic efficiency with catechin as a substrate could contribute to anthocyanin degradation via mechanisms such as copolymerization.
Raspberry juice is a nutrient-rich beverage valued for its high concentrations of anthocyanins, vitamin C, and volatile aroma compounds, which contribute to its health benefits and sensory appeal. However, processing methods can significantly impact these quality attributes. This study compared the effects of thermal pasteurization (TT), high-pressure processing (HPP), and pulsed electric fields (PEF), each at two intensity levels, on the physico-chemical and sensory properties of raspberry juice. Evaluated parameters included colour, viscosity, turbidity, browning index (BI), anthocyanin stability, ascorbic acid retention, and volatile aroma compounds. Thermal treatments caused significant colour changes, accelerating browning reactions and degrading anthocyanins and floral aroma compounds. Higher thermal treatment (80 degrees C) resulted in the most pronounced browning and colour loss, reducing sensory quality. HPP treatments demonstrated pressure-dependent effects, with low-intensity HPP treatment causing the highest BI due to enzyme activation, while high-intensity HPP moderated browning. HPP also reduced viscosity and turbidity likely due to pectin degradation. In contrast, PEF-treated samples exhibited minimal changes in colour and browning but retained the lowest ascorbic acid levels, likely due to temperature spikes during processing. Multifactorial analysis identified volatile aroma compounds, particularly alpha-ionone and beta-ionone, along with viscosity, turbidity, and BI, as the key differentiating factors among treatments. Particularly, ascorbic acid was not a primary contributor to the model, highlighting its limited role in treatment differentiation. The findings suggest that high-intensity PEF treatment offers the appropriate balance between nutrient retention and sensory quality, while TT and HPP treatments require optimization to minimize quality losses.
Dihydrochalcones are secondary metabolites with manifold dietary and pharmaceutical properties, but with a yet unclear function in plants. The abundance of dihydrochalcones, particularly phloridzin, makes Malus ssp. unique in the plant kingdom. The gene(s)/enzyme(s) for the key reaction in phloridzin biosynthesis, the reduction in the C3-bridge connecting the aromatic rings A and B of chalcones, have long been searched for. To date, two possible pathways to phloridzin have been described, one via the reduction in p-coumaroyl-CoA and the other via the reduction in naringenin chalcone. In this work, an enzyme from apple leaves, which catalyses the reduction in p-coumaroyl-CoA, was purified and partially sequenced. The newly identified hydroxycinnamoyl-CoA double bond reductase (HDR) has not been mentioned in the context of phloridzin biosynthesis so far. Long-read sequencing and sequence analyses in search of transcriptional and translational variants predicted a MdHDR proteoform potentially formed by alternative translational initiation. Heterologous expression of the two HDR proteoforms in E. coli showed that recombinant HDR is able to reduce p-coumaroyl-CoA beside other hydroxycinnamic acid CoA esters, whereas other substrates including the corresponding free hydroxycinnamic acids and naringenin chalcone were not accepted. Heterologous expression of the HDR proteoforms in A. thaliana resulted in the formation of O-hexosylated dihydrocinnamic acids, confirming the functional activity of the HDR as a reductase in planta, but no phloretin derivatives were detected. Our findings support the presence of an alternative pathway to the recently described reduction in naringenin chalcone in the biosynthesis of dihydrochalcones.
Vegetative propagation of European grapevine (Vitis vinifera L.) requires grafting onto American rootstocks due to susceptibility to phylloxera. However, the grafting yield is compromised by the presence of grapevine trunk diseases (GTDs) such as Esca. This study investigates the phenolic response and enzyme activity in grapevine callus from grafts obtained by scions with different GTD status (healthy, asymptomatic, and symptomatic) treated with different disinfection methods (Beltanol, Beltanol in combination with thermotherapy, Serenade® ASO, Remedier, BioAction ES, and sodium bicarbonate). Twenty-three phenolic compounds were identified in the graft callus, with flavanols, stilbenes, and condensed tannins predominating. Scion disinfection with BioAction ES led to a significant increase in total phenolic content in the callus, especially in symptomatic scions, for on average 510.3 µg/g fresh weight (FW) higher total phenolic content, compared to grafts where scions were treated with Beltanol. Phenolics such as epicatechin gallate, procyanidin derivatives, and resveratrol hexoside were significantly increased, indicating a strong elicitor effect of BioAction ES. Enzymatic activity analysis showed that the disinfection methods affected the activity of key enzymes involved in the phenylpropanoid metabolic pathway. In particular, BioAction ES significantly increased phenylalanine ammonia lyase (PAL) activity in callus from grafts with healthy scions by 3.4-fold and flavanone 3β-hydroxylase (FHT) activity in callus from grafts with infected scions by 4.9-fold (asymptomatic) and 6.9-fold (symptomatic) compared to callus from grafts with Beltanol-treated scions. The results highlight the potential of environmentally friendly disinfection methods, particularly BioAction ES, in influencing phenolic content and enzymatic activity in graft callus, potentially affecting the success of grapevine grafting.
This study investigated the impact of cultivar, harvest time, and ripening stage of strawberries on their aroma concentration and profile, and colour stability of nectars produced from these strawberries. Purees from 12 different cultivars from two countries, collected at different ripening stages and harvest times, were analysed. Furaneol and mesifuran content was analysed using a gas chromatography–flame ionisation detector (GC-FID), and gas chromatography–mass spectrometry (GC-MS) was used to determine the content of 12 aroma compounds, including esters, C6 compounds, and lactones. Nectars produced from these purees had their colour stability measured over 12 weeks. Both the colour and aroma were greatly influenced by strawberry cultivar. Within cultivars, nectars produced from strawberries that had been harvested overripe showed higher colour stability and higher concentrations of aroma compounds than those harvested ripe from an earlier harvest, although some cultivars were more affected by harvest time than ripening stage. Aroma compounds that correlated significantly (p < 0.05) with a good colour after storage included furaneol, ethyl butanoate, hexanal, γ-decalactone and γ-dodecalactone, as well as the total concentration of aroma compounds. Only γ-decalactone concentrations correlated significantly with overall nectar colour stability, although this could be due to cultivar effects.
This study investigates the effects of four preservation treatments: thermal pasteurization (TP), ohmic heating (OH), high-pressure processing (HPP), and pulsed electric fields (PEF), on the aroma and phenolic compounds of strawberry nectar, under equivalent microbial inactivation conditions (5-log reduction) on pilot-scale systems. Changes during 60 days of storage at 4 degrees C were also evaluated. HPP was the most effective method for retaining aroma compounds, with initial levels of 5.29 +/- 0.03 mg/L, closely to the untreated samples, while TP showed the lowest retention (2.94 +/- 0.13 mg/L). During storage, HPP-treated samples had a 41.6 % reduction in aroma compounds but still the highest remaining concentrations after storage compared to the other treatments. Key aroma markers, such as mesifurane, methyl and ethyl butyrate, were significantly better preserved in HPP and PEF treated samples compared to TP and OH. Phenolic content followed a similar trend: immediately after treatment HPP and PEF samples exhibited the highest total phenolic content (TPC), including anthocyanins like pelargonidin-3-glucoside, which constituted up to 81 % of total anthocyanins. Non-thermal methods (HPP and PEF) preserved phenolics better than TP, although differences between treatments were not significant after 60 days of storage. OH demonstrated intermediate performance due to its uniform heating process that minimized thermal degradation. Overall, non-thermal methods emerged as the most effective for preserving both aroma and phenolic profiles, followed by OH, while TP resulted in the greatest losses. These findings highlight the potential of non-thermal and alternative thermal technologies over thermal pasteurization to maintain the sensory and nutritional quality of fruit-based beverages.
Flavonoids are phenolic substances and exhibit strong antioxidant properties. The biosynthesis of flavonoids is regulated by various transcription factors (TFs), with MYB TFs playing a key role in controlling essential genes within this pathway. In this study, we identified candidate MYB TFs from our pulp transcriptome database of durian “Monthong” cultivar. MYBs exhibiting upregulation during the ripe stage were considered transcriptional activators, due to their positive correlation with flavonoid gene expression and flavonoid accumulation in ripe durian pulps. One candidate MYB activator, DzMYB1, which was highly expressed at the ripe stage, was selected for functional characterization. Studies involving transient expression of DzMYB1 in Solanum lycopersicum cv. Micro-Tom fruit demonstrated increased flavonoid content, as analyzed by LC–MS/MS, compared with the GFP control. Moreover, we showed that DzMYB1 controls flavonoid biosynthesis by interacting with the promoters of various flavonoid biosynthetic genes, including chalcone synthase, chalcone isomerase, and flavanone 3-hydroxylase, resulting in their transcriptional activation. Additionally, we found that DzMYB1 functions as a homodimer and binds to a homodimerized DzbHLH1 in the intricate regulation of flavonoid biosynthesis. These findings provide comprehensive insights into the functional roles of MYB protein in the regulation of the flavonoid pathway within durian pulps.
Flavonoids are phenolic substances and exhibit strong antioxidant properties. The biosynthesis of flavonoids is regulated by various transcription factors (TFs), with MYB TFs playing a key role in controlling essential genes within this pathway. In this study, we identified candidate MYB TFs from our pulp transcriptome database of durian 'Monthong' cultivar. MYBs exhibiting upregulation during the ripe stage were considered transcriptional activators, due to their positive correlation with flavonoid gene expression and flavonoid accumulation in ripe durian pulps. One candidate MYB activator, DzMYB1, which was highly expressed at the ripe stage, was selected for functional characterization. Studies involving transient expression of DzMYB1 in Solanum lycopersicum cv. Micro -Tom fruit demonstrated increased flavonoid content, as analyzed by LC-MS/MS, compared with the GFP control. Moreover, we showed that DzMYB1 controls flavonoid biosynthesis by interacting with the promoters of various flavonoid biosynthetic genes, including chalcone synthase, chalcone isomerase, and flavanone 3-hydroxylase, resulting in their transcriptional activation. Additionally, we found that DzMYB1 functions as a homodimer and binds to a homodimerized DzbHLH1 in the intricate regulation of flavonoid biosynthesis. These findings provide comprehensive insights into the functional roles of MYB protein in the regulation of the flavonoid pathway within durian pulps.
Among fruits, the apple is unique for producing large amounts of the dihydrochalcone phloridzin, which, together with phloretin, its aglycone, is valuable to the pharmaceutical and food industries for its antidiabetic, antioxidant, and anticarcinogenic properties, as well as its use as a sweetener. We analysed the phloridzin concentration, total phenolic content, and antioxidant activity in the peel, flesh, seeds, juice, and pomace of 13 international and local apple varieties. In the unprocessed fruit, the seeds had the highest phloridzin content, while the highest total phenolic contents were mostly found in the peel. In processed samples, phloridzin and the total phenolic compounds especially were higher mostly in juice than in pomace. Moreover, the total phenolic content was much higher than the phloridzin content. Juice showed the highest antioxidant activity, followed by the peel and flesh. Across all samples, antioxidant activity did not directly correlate with phloridzin concentrations, suggesting that the antioxidant activity ascribed to phloridzin may need re-evaluation. In the Ferric Reducing Antioxidant Power (FRAP) assay, phloridzin only showed antioxidant activity at high concentrations when compared to its aglycone, phloretin. Considering the large amounts of apple juice produced by the juice industry, residual pomace is a promising source of phloridzin. For technical use, processing this phloridzin to phloretin would be advantageous.
Herein an enzyme-assisted supercritical fluid extraction (EA-SFE) was developed using the enzyme mix snailase to obtain flavonols and dihydrochalcones, subgroups of flavonoids, from globally abundant waste product apple pomace. Snailase, a commercially available mix of 20-30 enzymes, was successfully used to remove the sugar moieties from quercetin glycosides, kaempferol glycosides, phloridzin and 3-hydroxyphloridzin. The resulting flavonoid aglycones quercetin, kaempferol, phloretin and 3-hydroxyphloretin were extracted using supercritical carbon dioxide (scCO2) and minimum amounts of polar cosolvents. A sequential process of enzymatic hydrolysis and supercritical fluid extraction was developed, and the influence of the amount of snailase, pre-treatment of apple pomace, the time for enzymatic hydrolysis, the amount and type of cosolvent and the time for extraction, was studied. This revealed that even small amounts of snailase (0.25 %) provide a successful cleavage of sugar moieties up to 96 % after 2 h of enzymatic hydrolysis followed by supercritical fluid extraction with small amounts of methanol as cosolvent, leading up to 90 % of the total extraction yields after 1 h extraction time. Ultimately, a simultaneous process of EA-SFE successfully demonstrates the potential of snailase in scalable scCO2 extraction processes for dry and wet apple pomace with satisfactory enzyme activity, even under pressurized conditions.
Historically, cannabis has always constituted a component of the civilized world; archaeological discoveries indicate that it is one of the oldest crops, while, up until the 19th century, cannabis fibers were extensively used in a variety of applications, and its seeds comprised a part of human and livestock nutrition. Additional evidence supports its exploitation for medicinal purposes in the ancient world. The cultivation of cannabis gradually declined as hemp fibers gave way to synthetic fibers, while the intoxicating ability of THC eventually overshadowed the extensive potential of cannabis. Nevertheless, the proven value of certain non-intoxicating cannabinoids, such as CBD and CBN, has recently given rise to an entire market which promotes cannabis-based products. An increase in the research for recovery and exploitation of beneficial cannabinoids has also been observed, with more than 10 000 peer-reviewed research articles published annually. In the present review, a brief overview of the history of cannabis is given. A look into the classification approaches of cannabis plants/species as well as the associated nomenclature is provided, followed by a description of their chemical characteristics and their medically valuable components. The application areas could not be absent from the present review. Still, the main focus of the review is the discussion of work conducted in the field of extraction of valuable bioactive compounds from cannabis. We conclude with a summary of the current status and outlook on the topics that future research should address.
The content of sugars, organic acids, phenolic compounds and selected enzyme activities in the anthocyanin pathway were analyzed in NIGRA (Sambucus nigra var. nigra—black fruits) and VIRIDIS (S. nigra var. viridis—green fruits) fruits over four stages of ripening. The share of glucose and fructose in green fruits was higher than in colored fruits, and the sugar content increased significantly until the third developmental stage. Ripe NIGRA berries had 47% flavonol glycosides, 34% anthocyanins, 3% hydroxycinnamic acids and 14% flavanols, whereas the major phenolic group in the VIRIDIS fruits, making up 88% of the total analyzed polyphenols, was flavonols. NIGRA fruits were rich in anthocyanins (6020 µg g−1 FW), showing strong activation of the late anthocyanin pathway (dihydroflavonol 4-reductase, anthocyanidin synthase). In both color types, phenylalanine ammonia lyase and chalcone synthase/chalcone isomerase activities were highest in the first stage and decreased during ripening. In VIRIDIS fruit, no anthocyanins and only one flavanol (procyanidin dimer) were found. This was most likely caused by a lack of induction of the late anthocyanin pathway in the last period of fruit ripening. The VIRIDIS genotype may be useful in studying the regulatory structures of anthocyanin biosynthesis and the contribution of distinct flavonoid classes to the health benefits of elderberries.
This study aimed at searching for the enzymes that are responsible for the higher hydroxylation of flavonols serving as UV-honey guides for pollinating insects on the petals of Asteraceae flowers. To achieve this aim, an affinity-based chemical proteomic approach was developed by relying on the use of quercetin-bearing biotinylated probes, which were thus designed and synthesized to selectively and covalently capture relevant flavonoid enzymes. Proteomic and bioinformatic analyses of proteins captured from petal microsomes of two Asteraceae species (Rudbeckia hirta and Tagetes erecta) revealed the presence of two flavonol 6-hydroxylases and several additional not fully characterized proteins as candidates for the identification of novel flavonol 8-hydroxylases, as well as relevant flavonol methyl- and glycosyltransferases. Generally speaking, this substrate-based proteome profiling methodology constitutes a powerful tool for the search for unknown (flavonoid) enzymes in plant protein extracts.
Anthochlor pigments (chalcones and aurones) play an important role in yellow flower colourization, the formation of UV-honey guides and show numerous health benefits. The B-ring hydroxylation of chalcones is performed by membrane bound cytochrome P450 enzymes. It was assumed that usual flavonoid 3′-hydroxlases (F3′Hs) are responsible for the 3,4- dihydroxy pattern of chalcones, however, we previously showed that a specialized F3′H, namely chalcone 3-hydroxylase (CH3H), is necessary for the hydroxylation of chalcones. In this study, a sequence encoding membrane bound CH3H from Dahlia variabilis was recombinantly expressed in yeast and a purification procedure was developed. The optimized purification procedure led to an overall recovery of 30% recombinant Dv CH3H with a purity of more than 84%. The enzyme was biochemically characterized with regard to its kinetic parameters on various substrates, including racemic naringenin, as well as its enantiomers (2 S )-, and (2 R )-naringenin, apigenin and kaempferol. We report for the first time the characterization of a purified Cytochrome P450 enzyme from the flavonoid biosynthesis pathway, including the transmembrane helix. Further, we show for the first time that recombinant Dv CH3H displays a higher affinity for (2 R )-naringenin than for (2 S )-naringenin, although (2 R )-flavanones are not naturally formed by chalcone isomerase.
Bidens ferulifolia is a yellow flowering plant, originating from Mexico, which is increasingly popular as an ornamental plant. In the past few years, new colour combinations ranging from pure yellow over yellow-red, white-red, pure white and purple have emerged on the market. We analysed 16 Bidens ferulifolia genotypes to provide insight into the (bio)chemical base underlying the colour formation, which involves flavonoids, anthochlors and carotenoids. In all but purple and white genotypes, anthochlors were the prevalent pigments, primarily derivatives of okanin, a 6′-deoxychalcone carrying an unusual 2′3′4′-hydroxylation pattern in ring A. The presence of a cytochrome-P450-dependent monooxygenase introducing the additional hydroxyl group in position 3′ of both isoliquiritigenin and butein was demonstrated for the first time. All genotypes accumulate considerable amounts of the flavone luteolin. Red and purple genotypes additionally accumulate cyanidin-type anthocyanins. Acyanic genotypes lack flavanone 3-hydroxylase and/or dihydroflavonol 4-reductase activity, which creates a bottleneck in the anthocyanin pathway. The carotenoid spectrum was analysed in two Bidens genotypes and showed strong variation between the two cultivars. In comparison to anthochlors, carotenoids were present in much lower concentrations. Carotenoid monoesters, as well as diesters, were determined for the first time in B. ferulifolia flower extracts.
Identifying feedstocks and their integral valorization is essential for the sustainable production of chemicals, materials, fuels, and energy. Waste materials from different agricultural activities can be a potential source. Specifically, winemaking and grape crops are a source of both the large amounts and variety of residues. The grapevine shoots are the primary residue resulting from the pruning of grape crops, consisting of the stems and leaves. More than 46 thousand hectares in Austria are dedicated to grape crops, and al-most half of this area corresponds to the variety Gruner Veltliner. Italian, Portuguese, and Spanish grapevine residues have been studied to produce bioactive compounds; however, the most important Austrian grape variety has not been thoroughly studied for this purpose. The grapevine shoots offer different lignocellulosic platforms and valorization strategies if the leaves and stem are evaluated separately. This work evaluated the ex-traction of bioactive compounds and the production of hemicellulosic sugars, lignin, and a cellulose-enriched pulp from Gruner Veltliner's grapevine shoots under a biorefinery concept. Pressurized Liquid Extraction was the selected technology for extracting bioac-tive compounds, and Liquid Hot Water and Organosolv were chosen for hemicellulose and lignin hydrolysis. Quercetin was the flavonoid found in higher concentrations in the leaves (10.6 mg/g of dry feedstock) and resveratrol in the stems (1.9 mg/g of dry feedstock); both components were found in higher yields than other grape varieties reported in the literature. In addition, hemicellulose and lignin hydrolysis reached yields (0.18 and 0.08 g/ g of dry feedstock, respectively) in the same order of magnitude as other feedstock used for hemicellulose and lignin valorization (e.g., wheat straw). These results clearly show the potential of this under-valorized feedstock and encourage further study of the downstreaming of the intermediate products and a deeper study of the production cycle of the shoots to determine the actual available amount to be used. (c) 2022 The Author(s). Published by Elsevier Ltd on behalf of Institution of Chemical Engineers. This is an open access article under the CC BY license (http://creative-commons.org/licenses/by/4.0/).