Influence of Novel EnZolv Pretreatment on the Release of Reducing Sugar and Proximate Content of Banana Fiber

Lignocellulosic biomass (LCB) from agriculture residues has gained a lot of attention in recent years for its conversion to useful by-products. The one drawback that the conversion of biomass faces is its recalcitrant nature which can be overcome by effective pretreatment technology. One such process is the EnZolv, a novel pretreatment technique used for delignification of biomass and it was recognized as an eco-friendly approach. The main objective of our present study is to optimize the novel EnZolv process parameters for enhanced release of reducing sugar from banana fiber. Banana fiber pre-optimization for EnZolv pretreated at 100% moisture content, incubated at 40 °C temperature, with an enzyme load of 50 U·g-1 of biomass for an incubation time of 5 h at a shaking speed of 100 rpm yielded enhanced sugar release of 1.7 mg·mL-1. The effect of pretreatment on proximate composition results in a decrease in the volatile matter (53%) and moisture percentage (1.07%) and an increase in the other parameters such as ash content (12%) and fixed carbon content (34%) under the optimized condition. A significantly higher release of phenol content 1264 µg·mL-1 equivalent to gallic acid suggests that EnZolv pretreatment confirms the degradation of lignin content in the biomass.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12088-023-01130-4.

Optimization of ultrasound-assisted extraction of phenolic content & antioxidant activity of hog plum (Spondias pinnata L. f. kurz) pulp by response surface methodology

Background

The pulp of hog plum (Spondias pinnata L. f. kurz) has been documented as a potential source of nutritional, physiological, and pharmacological purposes due to its phenolic content (TPC) and antioxidant activity. However, an optimal extraction condition for hog plum pulp remains elusive. Optimization of extraction process conditions using Ultrasound-assisted extraction (UAE) technique has recently attracted research interest.

Objectives

The present study focused on optimizing the UAE extraction conditions of TPC and antioxidant activities (DPPH and FRAP) from hog plum pulp by using response surface methodology (RSM).

Methods

The RSM with a three-factor-three-level Box-Behnken design (BBD) was used to optimize the extraction conditions. The BBD was used to investigate the effects of three independent variables, X₁: ultrasonic temperature (40–60 °C), X₂: ultrasonic time (30–60 min), and X₃: ethanol concentration (40–80%) on TPC, DPPH and FRAP assays. Fifteen experimental trials have been carried out to optimize the UAE extraction conditions. A second-order polynomial model was used for predicting the responses. Statistically, the model was validated using an analysis of variance (ANOVA).

Results

The ANOVA results revealed that UAE extraction temperature, time, and ethanol concentration had a significant (p < 0.01) influence on the TPC, DPPH, and FRAP, suggesting that all extraction parameters included in this investigation were crucial to the optimization process. For TPC, DPPH, and FRAP, the R² values were 0.9976, 0.9943, and 0.9989, respectively, indicating that the models developed based on second-order polynomials were satisfactorily accurate for analyzing interactions between parameters (response and independent variables). RSM analysis showed that the optimal extraction parameters which maximized TPC, DPPH, and FRAP were 52.03 °C temperature, 30 min, time, and 79.99% ethanol. Under optimal conditions, experimental values for TPC, DPPH, and FRAP were 370 ± 26 mg GAE/100g DM, 57 ± 7%, and 7650 ± 460 mg AAE/100 g DM, respectively. The experimental values showed a good agreement with the predicted values with residual standard error values below 0.2% under optimum conditions. Pearson's correlation coefficients (r) demonstrate that the TPC showed a weak positive correlation with DPPH (r = 0.3508) and moderate correlation with FRAP (r = 0.3963).

Conclusion

The experimental results agreed with the predicted values, confirming the model's appropriateness and RSM's efficacy in optimizing the UAE extraction conditions. This optimized UAE extraction method may be effective in the industrial extraction process; moreover, further research should be conducted to determine the efficacy of these extracts when applied to food.

Effect of thermal processing on quality of tender jackfruit in tin-free-steel cans

Thermal processing is the most efficient and economical technique for the long-term preservation of tender jackfruit in ready-to-cook form on a commercial-scale. Although, thermal processing primarily focus on microbiological safety of the product, the associated quality changes need to be examined as it is decisive of consumer acceptance. The present study investigated the effect of two pasteurization (90 and 100 °C) and sterilization temperatures (110 and 121 °C) at different lethality on microbiological, colour, texture, ascorbic acid (AA), total flavonoid (TFC) and phenol (TPC) contents of tender jackfruit processed in tin-free-steel (TFS) cans. Time required for thermal processing was computed from respective heat penetration curve. Thermal processing improved both the TFC and TPC of tender jackfruit, while colour, texture and AA had degraded. Based on microbiological and physicochemical quality analyses, the study adjudged pasteurization at 90 °C for 19 min and sterilization at 121 °C for 8 min as the best temperature-time combination for thermal processing of tender jackfruit in TFS cans.

Saponins and flavonoids from Bacopa floribunda plant extract exhibit antioxidant and anti-inflammatory effects on amyloid beta 1-42-induced Alzheimer's disease in BALB/c mice

ETHNOPHARMACOLOGICAL RELEVANCE

Bacopa floribunda (BF), a locally available plant has been employed traditionally as memory enhancer in Southwestern, Nigeria. It has been utilized in traditional and Ayurvedic medicine as brain tonic for enhancing memory, anti-aging and forestalling series of psychological disorders. However, there is a dearth of scientific information on the mechanism(s) of action of important phytochemicals from BF extract on dementia.

AIM OF THE STUDY

Alzheimer's disease, the commonest form of dementia has been postulated to triple by 2050 as a result of increase in life expectancy. This study therefore assessed and compared the possible mechanism(s) of action of flavonoids and saponins from BF on Amyloid beta (Aβ1-42)-induced dementia in male BALB/c mice.

MATERIALS AND METHODS

Eighty (80) healthy BALB/c mice divided into 10 groups (n = 8) were given a single bilateral ICV injection of Aβ1-42 or normal saline. Graded doses of Saponins and flavonoids (50, 100 and 200 mg/kg) were used as treatment for 21 days. Hippocampal homogenates were assayed for the levels of antioxidants, oxidative stress and neuroinflammatory markers. In vitro antioxidant activity of flavonoids and saponins were equally assessed using standard procedures. The extent of microglial activation was quantified through immunohistochemistry procedure.

RESULTS

Aβ1-42 successfully caused a spike in hippocampal levels of MDA, IL1β, TNF-α including MPO levels and invariably decreased antioxidant activities. Likewise an increase in reactive microglia (microgliosis) was observed. However, crude saponins and flavonoids from BF were able to suppress microgliosis, oxidative stress and neuroinflammation induced by Aβ1- 42 and were observed to be more effective at higher doses of saponins (100 mg/kg and 200 mg/kg) and flavonoid (100 mg/kg).

CONCLUSIONS

Phytochemicals from BF efficiently exhibited dose dependent alleviation of some symptoms associated with Alzheimer's disease.

Phytochemical screening, total polyphenol, flavonoid content, in vitro antioxidant and antibacterial activities of Sri Lankan varieties of Murraya koenigii and Micromelum minutum leaves

The use of plant materials in traditional medicine as a significant ingredient in synthesizing drugs in the form of decoctions had played a vital role due to their potential therapeutic action. The curry leaves, Murraya koenigii, and Micromelum minutum are two most common aromatic herbs widespread in Sri Lanka and many other Asian countries. They are rich in nutrition and exert several medicinal properties such as antidiabetic, antioxidant, antimicrobial, anti-inflammatory, and anti-carcinogenic due to various essential phytochemicals, minerals, and trace minerals. In this study, we determined the proximate composition, in vitro antioxidant activity, total phenol (TPC), flavonoid content (TFC), and antibacterial activity in both species using standard methods. Results showed that both species varied greatly in nutritional composition, antioxidant, and antibacterial activities. The nutrient composition in terms of ash, crude protein, and fat was significantly high in M. koenigii based on dry weight basis. In vitro antioxidant potential of M. koenigii and M. minutum was evaluated by means of the DPPH radical scavenging assay, and the IC₅₀ values of M. koenigii and M. minutum were 107 ± 2 μg/mL and 208 ± 4 μg/mL, respectively. The TPC and TFC of M. koenigii were 101 ± 1 mg GAE/g and 9.75 ± 0.05 mg QE/g, and M. minutum were 80 ± 2 mg GAE/g and 9.16 ± 0.02 mg QE/g respectively. The antibacterial study was assessed against three bacterial strains. The study showed the highest inhibitory activity for M. koenigii and M. minutum against Staphylococcus aureus and Escherichia coli, respectively at 1.0 mg/mL concentration. The study indicated that M. koenigii possessed a significantly high TPC, and TFC correlated with higher antibacterial and antioxidant activity than M. minutum.

Effect of different pretreatments followed by hot-air and far-infrared drying on the bioactive compounds, physicochemical property and microstructure of mango slices

In recent years there is an increasing interest in dried fruits, although many of their nutritional components are readily lost during drying. The novelty of this paper was to assess the effect of hot-air drying (HAD) and far-infrared drying (FIRD) on the physicochemical properties and microstructure of mango slices pretreated with: control; 0.1% citric acid + 0.5% ascorbic acid + 0.5% CaCl₂ + 1% NaCl; or 0.1% citric acid + 0.5% ascorbic acid + 0.5% CaCl₂ + 1% NaCl + ultrasound treatments. Pretreatments resulted in a significant (p < 0.05) increase in reducing sugar, ascorbic acid and total phenol contents of dried samples. Moreover, compared with HAD, FIRD maintained a higher phenolic acid content, improved the nutrient retention and color attributes and better preserved microstructure. Therefore, pretreatments followed by FIRD is a potential method for obtaining high-quality dried mango slices.

Antioxidant potentials of successive solvent extracts from the unexplored Hedhychium coronarium rhizome

Hedychium coronarium Koen. is considered as an endemic medicinal plant. In the current research antioxidant potential of six different extracts obtained by the successive solvent extraction method from the unexplored H. coronarium rhizome was evaluated. Various in vitro assays were performed to achieve the aim and variation in scavenging potential of the six extracts, in addition to quantification of phenolic and flavonoid compounds was done by HPLC. Among the six extracts, methanolic extract have showed highest Total phenolic content (TPC), metal chelation activity and free radical scavenging potential against DPPH, ABTS and superoxide anions as compared to other extracts. The highest scavenging potential against nitric oxide and hypochlorus acid was shown by acetone extract. The variation in anti-oxidant activity of the extracts may be due to the phyto-constituents present in different solvents. A significant correlation (r² = 0.864) was established between antioxidant and TPC of H. coronarium from principle component analysis. Thus the present study provides strong evidence that rhizome extract of H. coronarium is a potential source of bioactive compounds and can be used as a remedy for diseases caused due to oxidative stress. Reported results could be helpful to develop novel drugs for the management of oxidative stress and associated diseases.

Storage quality of shelled green peas under modified atmosphere packaging at different storage conditions

Storage quality of shelled green peas (Pisum sativum var. sativum L) was investigated under modified atmosphere packaging (MAP: perforated and non perforated) compared to unsealed samples, respectively, at T1 (4 ± 1 °C and 94 ± 2 % RH) and T2 (10 ± 1 °C and 90 ± 2 % RH) for each sample and during period of storage (8, 16 and 24 days). Modified atmosphere (MA) was created using low density polyethylene (LDPE) film packages having 107 μm of film thickness and package size of 0.022 m(2). Quality parameters viz., weight loss (WL), total phenolic content (TPC), instrumental colour, ascorbic acid (AA) and sensory characteristics were evaluated during storage period. Weight loss was in the range of 0.18 to 3.54 (zero perforation at T1), 0.21 to 6.48(unsealed samples at T2) and 0.31 to 9.64 % (zero perforation at T1) after 8, 16 and 24 days of storage, respectively. Total phenolic content significantly increased to 102.47-161.54 mg/100 g from an initial value of 91.53 mg/100 g for all the samples and treatments studied. The MAP non perforated sample stored at T2 recorded maximum Hunter 'L' and '-a' colour values than all other samples. A significant decrease in AA content was observed in all the samples with maximum loss (53.77 %) in unsealed sample stored at T2, whereas MAP (3 perforations) sample stored at T1 retained maximum AA (90.50 %). Sensory quality analysis revealed that MAP (3 perforations) sample stored at T1 was in acceptable quality, with good appearance and overall acceptance. The study shows that shelled green peas can be stored in MAP with 3 perforations (0.4 mm dia) in the temperature range of 4 to 10 °C and 90-94 % RH to extend shelf life with marketable quality for 24 days.

Comparison Between Different Flavored Olive Oil Production Techniques: Healthy Value and Process Efficiency

Three different flavoring methods of olive oil were tested employing two different herbs, thyme and oregano. The traditional method consist in the infusion of herbs into the oil. A second scarcely diffused method is based on the addition of herbs to the crushed olives before the malaxation step during the extraction process. The third innovative method is the implementation of the ultrasound before the olive paste malaxation. The objective of the study is to verify the effect of the treatments on the quality of the product, assessed by means of the chemical characteristics, the phenol composition and the radical scavenging activity of the resulting oils. The less favorable method was the addition of herbs directly to the oil. A positive effect was achieved by the addition of herbs to the olive paste and other advantages were attained by the employment of ultrasound. These last two methods allow to produce oils "ready to sell", instead the infused oils need to be filtered. Moreover, the flavoring methods applied during the extraction process determine a significant increment of phenolic content and radical scavenging activity of olive oils. The increments were higher when oregano is used instead of thyme. Ultrasound inhibited the olive polyphenoloxidase, the endogenous enzyme responsible for olive oil phenol oxidation. This treatment of olive paste mixed with herbs before malaxation was revealed as the most favorable method due to the best efficiency, reduced time consumption and minor labor, enhancing the product quality of flavored olive oil.

Total Phenol Content and In Vitro Antioxidant Potential of Helicanthus elastica (Desr.) Danser-A Less-explored Indian Mango Mistletoe

Natural products are an important source of antioxidant molecules like tannins, phenolic compounds, flavonoids, etc., Helicanthus elastica (Desr.) Danser (Loranthaceae) is one such plant belonging to the category of mistletoe, and grows commonly on the mango trees in India. In the present study, an attempt has been made to assess the antioxidant properties of the plant. Ethanol extract of H. elastica growing on mango tree was studied using different in vitro models. Shade-dried whole plant material was extracted with ethanol by cold percolation. Fifty milligrams of the alcohol extract of H. elastica was weighed and dissolved in 10 ml of methanol. The resultant 5 mg/ml solution was suitably diluted to obtain different concentrations. Total phenol content, reducing power assay, and scavenging of free radicals like nitric oxide, hydroxyl, hydrogen peroxide, and 1,1-diphenyl-2-picrylhydrazyl were studied by standardized in vitro chemical methods using ascorbic acid as the standard. The total phenol content of the plant was found to be 1.89% w/w. The extract showed good reducing power as well as scavenging of free radicals (nitric oxide, hydroxyl, superoxide anion, and hydrogen peroxide) at concentrations ranging from 5 to 100 μg/ml. The study revealed the antioxidant potential of H. elastica.

Antioxidant and electrochemical properties of cultivated Pleurotus spp. and their sporeless/low sporing mutants

Methanolic extracts of four cultivated edible mushrooms of Pleurotus spp. namely Pleurotus florida, Pleurotus sajor-caju, Pleurotus cystidiosus and Pleurotus djamor along with the sporeless/low sporing mutants of Pleurotus florida, and Pleurotus sajor-caju were analyzed for their antioxidant activity using different chemical assays. The electrochemical behaviors of these extracts were also analyzed using cyclic voltammetry and differential pulse voltammetry. Results showed that scavenging effects on 2,2-diphenyl-1-picrylhydrazyl radicals were good (73.3-42.4 %) at 1.5 mg/ml. At 12 mg/ml, the reducing powers (2.54-1.71) and chelating effects on ferrous ions (56.0-78.5 %) were excellent. H2O2 scavenging abilities at 1.5 mg/ml showed a wide range (20.0-85.4 %). Scavenging of superoxide radicals were excellent and were found to be in the range of 61.1-90.0 % at 16 mg/ml concentration. FRAP results were in the range of 1.20 - 0.98 at 16 mg/ml. Total phenolic and total flavonoid contents of the methanolic extracts ranged from 22.67 to 36.03 mg/g and 1.19-2.94 μg/g respectively. The study assessed the amount of variation in antioxidant activities exhibited by different cultivated species and their sporeless/low sporing mutants.

Physical and chemical characteristics of goldenberry fruit (Physalis peruviana L.)

Some physical and chemical characteristics of goldenberry fruit (Physalis peruviana L.) were investigated. These characteristics are necessary for the design of equipments for harvesting, processing, transportation, sorting, separating and packing. The fruit length, diameter, geometric and arithmetic mean diameters, sphericity, surface area, projected areas (vertical-horizontal) and aspect ratio of goldenberries were determined as 17.52 mm, 17.31 mm, 17.33 mm, 17.38 mm, 98.9 %, 0.949 cm(2), 388.67-387.85 mm(2) and 0.988, respectively. The mass of fruit, bulk density, fruit density, porosity and fruit hardness were 3.091 g, 997.3 kg/m(3), 462.3 kg/m(3), 53.61 % and 8.01 N, respectively. The highest static coefficient of friction was observed on rubber surface, followed by stainless steel sheet, aluminum sheet, and plywood materials. The dry matter, water soluble dry matter, ash, protein, oil, carbohydrate, titratable acidity, pH, total sugar, reducing sugar, antioxidant capacity were 18.67 %, 14.17 %, 2.98 %, 1.66 %, 0.18 %, 13.86 %, 1.26 %, 6.07, 63.90 g/kg, 31.99 g/kg and 57.67 %, respectively. The fresh fruits have 145.22 mg gallic acid equivalent (GAE)/100 g total phenol content and skin colour data represented as L*, a*, b*, Chroma (C) and Hue angle (α) were 49.92, 25.11, 50.23, 56.12 and 63.48, respectively.

Antioxidant and electrochemical properties of cultivated Pleurotus spp. and their sporeless/low sporing mutants

Methanolic extracts of four cultivated edible mushrooms of Pleurotus spp. namely Pleurotus florida, Pleurotus sajor-caju, Pleurotus cystidiosus and Pleurotus djamor along with the sporeless/low sporing mutants of Pleurotus florida, and Pleurotus sajor-caju were analyzed for their antioxidant activity using different chemical assays. The electrochemical behaviors of these extracts were also analyzed using cyclic voltammetry and differential pulse voltammetry. Results showed that scavenging effects on 2,2-diphenyl-1-picrylhydrazyl radicals were good (73.3-42.4 %) at 1.5 mg/ml. At 12 mg/ml, the reducing powers (2.54-1.71) and chelating effects on ferrous ions (56.0-78.5 %) were excellent. H2O2 scavenging abilities at 1.5 mg/ml showed a wide range (20.0-85.4 %). Scavenging of superoxide radicals were excellent and were found to be in the range of 61.1-90.0 % at 16 mg/ml concentration. FRAP results were in the range of 1.20 - 0.98 at 16 mg/ml. Total phenolic and total flavonoid contents of the methanolic extracts ranged from 22.67 to 36.03 mg/g and 1.19-2.94 μg/g respectively. The study assessed the amount of variation in antioxidant activities exhibited by different cultivated species and their sporeless/low sporing mutants.

Assessment of effect of hydroalcoholic and decoction methods on extraction of antioxidants from selected Indian medicinal plants

OBJECTIVE

To assess the effects of extraction methods on antioxidant activities of selected Indian medicinal flora.

METHODS

Different parts of plants were extracted by hydroalcoholic and decoction methods using water and various concentrations of methanol (ME) viz. 75%, 50% and 25% ME. The antioxidant activity of all the different extracts was evaluated using two different antioxidant assays viz. 2,2-diphenyl-1-picryl hydrazyl (DPPH) free radical scavenging assay and superoxide anion radical scavenging assay. Total phenol and flavonoid content was also estimated.

RESULTS

The results showed that the extracting solvent significantly altered the antioxidant property estimations of screened plants. High correlations between phenolic compositions and antioxidant activities of extracts were observed. High levels of antioxidant activities were detected in Manilkara zapota (M. zapota) as compared with other screened plants.

CONCLUSIONS

The results obtained appear to confirm the effect of different methods on extraction of antioxidants and antioxidant property of M. zapota.

Antioxidant properties and electrochemical behavior of cultivated commercial Indian edible mushrooms

Methanolic extracts of cap and stipe of commercially obtained mushrooms Agaricus bisporus, Hypsizygus ulmarius, and Calocybe indica were analyzed for their antioxidant activity in different chemical systems including reducing power, free radical scavenging, ferric reducing antioxidant power (FRAP), superoxide scavenging, peroxide scavenging, metal chelating activities and electrochemical behavior. Scavenging effects on 2,2-diphenyl-1-picrylhydrazyl radicals were moderate (43.5-59.0%) at 1.5 mg/ml. Chelating effects on ferrous ions were moderate to excellent (40.6-96.1%) at 20 mg/ml. At 12 mg/ml, the reducing powers were excellent (2.54-1.71). FRAP results were in the range 2.15-0.98 at 16 mg/ml. The ability to scavenge H2O2 was moderate to excellent (48.9-97.7%) at 1.5 mg/ml. At 10 mg/ml, Agaricus bisporus cap proved to be better at scavenging superoxide radicals than others. Similar electrochemical responses of all extracts suggested similar electroactive chemical composition. The total phenols in the extracts ranged from 14.73-26.72 mg/g.The total flavonoid content ranged from 1.12-2.17 μg/g.