Chestnut (
Castanea sativa) shell and eucalyptus (
Eucalyptus globulus) bark, waste products of the food and wood industries, respectively, were analysed as potential sources of antioxidant ...compounds. The extraction yield, the antioxidant activity and total phenols content of the extracts were greater in chestnut shell than in eucalyptus bark for most of the extraction conditions essayed. Extraction of chestnut shell with a 2.5% Na
2SO
3 aqueous solution led to the highest extraction yield, 25.6%, total phenols, 13.4
g gallic acid equivalent/100
g oven-dried shell, and FRAP antioxidant activity, 80.7
mmol ascorbic acid equivalent/100
g oven-dried shell. Extraction with methanol:water (50:50, v/v) provided the best results for eucalyptus bark. The antioxidant activity and the total phenols content of the extracts had a positive linear correlation. FTIR spectroscopy confirmed the higher content of phenolic compounds in chestnut shell extracts compared to eucalyptus bark extracts. Chestnut shell extracts were characterized by the presence of high molecular weight species whereas lower molecular weight species were predominant in eucalyptus bark extracts.
•Optimization of chestnut shells extraction using response surface methodology.•Subcritical water extraction is a clean method for antioxidants extraction.•Optimum extraction conditions: temperature ...220 °C and extraction time 30 min.•Caffeoylquinic acid isomers were the main phenolic compounds.
The objective of this study was to evaluate the optimal Subcritical Water Extraction (SWE) conditions of antioxidants and polyphenols from chestnut shells using Response Surface Methodology (RSM). A central composite design (CCD) was conducted to analyse the time (6–30 min) and temperature (51–249 °C) effects in antioxidant activity (ABTS, DPPH and FRAP) and Total Phenolic Compounds (TPC). TPC ranged from 315.21 to 496.80 mg gallic acid equivalents (GAE)/g DW; the DPPH from 549.23 to 1125.68 mg Trolox equivalents (TE)/g DW; ABTS varied between 631.16 and 965.45 mg ascorbic acid equivalents (AAE)/g DW and FRAP from 2793.95 to 11393.97 mg ferrous sulphate equivalents (FSE)/g DW. The optimal extraction conditions were 30 min/220 °C, revealing excelling scavenging efficiencies against HOCl (IC50 = 0.79 µg/mL) and O2− (IC50 = 12.92 µg/mL) without toxicity on intestinal cells (0.1 µg/mL). The phenolic composition revealed high amounts of pyrogallol and protocatechuic acid. SWE can be a useful extraction technique for the recovery of polyphenolics from chestnut shells.
To establish an effective protocol for plant regeneration through indirect organogenesis, effects of expiants type, culture media and plant growth regulators on callus induction and shoot ...regeneration of chestnut (Castanea sativa Mill.) were investigated. Three different expiants (root, nodal and internodal segment), two different media Murashige and Skoog medium (MS) and Gamborg's B5 (B5) and different plant growth regulators (6-benzylaminopurine (BA), thidiazuron (TDZ), indole-3-butyric acid (IBA) and indole-3-acetic acid (IAA)) with different concentration (0.2, 0.5, 1 and 1.5 mgL super(-1)) for shoot and root induction were chosen. The results show that nodal segment was the best explant for callus induction (69.4%) when cultured on MS medium supplemented with 1 mgL super(-1) TDZ and MS was the best medium to induce callus formation (74.6%). The highest shoot multiplication (66.9%) was observed on MS medium with 0.2 mgL super(-1) TDZ. Regenerated shoots were rooted in vitro on MS containing 1.5 mgL super(-1) IBA. Also, plantlets with well developed root and shoot systems were acclimatized inside the green house and 80% of the plantlets survived on transfer to garden soil. This protocol provides a basis for future studies on genetic improvement.
In domesticated species, translocation of materials can alter natural demographic patterns; this may have occurred in Castanea sativa (European chestnut), a species conserved in several refuges, with ...a long domestication history for nut production. Bayesian analysis of population genetic structure in marginal areas and in the centre of C. sativa range, considering spatial information and making corrections for unbalanced size, allowed visualization of a genetic structure that was subsequently analysed by approximate Bayesian computation to assess its natural demographic history and test the origin of some hypothetical translocated germplasm. We obtained evidence of C. sativa population contraction during the earliest Pleistocene, resulting in a split into eastern (Greek) and western (Italian and Iberian) populations. The northern Iberian population, in the Eurosiberian area, is one of the vestiges that remained after the contraction that split the global Tertiary population. A secondary encounter, occurred from Middle to Upper Pleistocene, which explains the hybrid origin of the Western Mediterranean population present in Italy and in the centre and south of the Iberian Peninsula. It has been demonstrated that a germplasm translocation from Italy to the Central Iberian Range may have occurred. Recent translocations have hybridized with the local northern Iberian population, producing naturalized populations with high diversity. The populations of C. sativa in southwestern Europe have a genetic structure compatible with a natural origin, in which signs of population contractions and expansions caused by climatic oscillations since the Late Miocene have been imprinted.
The research problem is to reduce the use of chemical coagulants by seeking more sustainable alternatives to water treatment. The use of Moringa oleifera (MO) is a good alternative coagulant agent, ...indicated in the water treatment system, in its clarification process, in addition to being biodegradable, but there is a need to look for other seeds that also have potential for be used as natural coagulants, in this context, it is justified to study other typical seeds from Portugal, where this study was carried out, to be used as an alternative natural coagulant. The hypothesis of this project is: among the typically European seeds selected for evaluation, seeds with high potential for use as a natural coagulant for use in water treatment will be found. This project aims to identify seeds, typical of Portugal, with similar potential to Moringa oleifera Lam to be used as a natural coagulant. The project was carried out in partnership with UFS, IFS and ISEP, where experiments were carried out with synthetic water with turbidity ranging from 40 to 350 NTU. The seeds used were four different types of European chestnuts, American and Portuguese nuts, plantain and Moringa oleifera, in addition to chestnut and walnut shells. From the results found, the Spanish chestnuts stand out with a turbidity removal efficiency of up to 69.8% in high turbidity water, in addition to the MO with a removal efficiency of 89.8% in high turbidity water.
•HPP at 600 MPa for 5 min avoided molds and larvae growth on chestnuts.•The shelf-life of chestnuts treated at 600 MPa was extended in 40 days compared to HT.•Chestnuts treated by HPP preserved ...better their nutritional composition.•Softer texture and dark color observed on kernel chestnuts processed by HPP.•HPP processed chestnuts could be peeled more quickly and easily.
High-pressure processing (HPP) is an emergent technology for nonthermal pasteurization of foods, which here demonstrates the potential to be used by the chestnut industry. This study evaluated HPP as a post-harvest processing technology to control molds and insect larvae proliferation in chestnuts (Castanea sativa Mill.) and improve the fruit's shelf-life. Chestnuts were processed by HPP (400, 500, and 600 MPa for 5.0 min at 20 °C) and the conventional hydrothermal technology (HT, 50 °C for 45 min). Untreated chestnuts were also used as a control group. Shelf-life studies were conducted for 60 d at i) 25 °C and 40 % relative humidity (RH); and ii) 5 °C and 70 % RH. After the treatment and over the storage period, parameters such as color, texture, weight loss, nutritional composition, ascorbic acid, and fungal load were evaluated. The results showed that immediately after the HPP treatments, the chestnuts became slightly softer than HT samples. Fruit treated by HPP maintained their nutritional composition and ascorbic acid content. During the first 30 d of storage, no changes of color were observed in treated fruit. Also, the shelf-life of chestnuts treated at 600 MPa was extended by 40 d, compared to HT, where no molds at a detectable level and insect larvae were observed when stored at 5 °C. This storage condition also reduced the fruit weight losses. Compared with HT, HPP has short processing times, which is an important advantage. In addition, the observed changes of texture as softening and easy peeling can be useful for obtaining ready-to-eat products since chestnuts looked partially cooked. However, its possible application at the industrial level should be adequately investigated based on the promising results obtained.
The potential of chestnut shell and eucalyptus bark extracts as phenol substitutes in the formulation of adhesives, as chrome substitutes in leather tanning and as a source of antioxidants compounds ...has been studied. The influence of extraction conditions, type and concentration of alkaline compounds (NaOH, Na
2SO
3 and Na
2CO
3) and temperature, on extraction yield and on extract characteristics: Stiasny number, tannin content, total phenols content, FRAP (ferric reducing/antioxidant power) antioxidant capacity and molecular weight distribution was analysed. Chestnut shell extracts had much better properties than eucalyptus bark extracts and significantly higher extraction yields were obtained. The increase of temperature from 70 to 90
°C not only increased the extraction yield but also improved the quality of the extracts. For both materials, the 2.5% Na
2SO
3–90
°C extract, together with the 2.5% NaOH–2.5% Na
2SO
3–90
°C extract for chestnut shell, showed high extraction yields and the best properties for all the applications proposed.
Shoots from European chestnut and hybrids of European and Asian chestnuts can be efficiently proliferated in liquid medium by temporary immersion (TIS) using RITA
and Plantform™ bioreactors. The main ...challenges of applying TIS to these species were the lack of growth and hyperhydricity; problem solutions included the manipulation of the hormone concentration, the explant type, immersion frequency, and a support for maintaining shoots in a vertical position. After protocol optimization, explants cultured by TIS produced more rootable shoots than explants growing in semisolid medium, enabling increased number of rooted and acclimatable shoots. In this chapter, we will describe the protocols for proliferating chestnut by TIS in RITA
and Plantform™ bioreactors, together with tips for avoiding the main pitfalls of the technique. The strategies applied to chestnut can be useful for culturing other woody plants in bioreactors.
The cultivation of sweet chestnuts in Slovakia has a century-year-old tradition. However, just a few research publications provide more comprehensive information about the chestnuts’ chemical ...composition of different varieties in individual growing areas. Sweet chestnuts contain various nutrients, of which carbohydrates are very important for assessing their commercial quality. Simple carbohydrates are mainly represented by glucose, fructose, sucrose, and maltose. The content of glucose was 0.178–3.152, fructose 0.271–3.170, sucrose 9.355–29.890, and maltose 0.171–1.584 g/100 g DW in chestnut samples from 27 sampling points, which are part of Slovakia’s four largest growing areas of sweet chestnuts. Carbohydrate contents were determined by the high-performance liquid chromatography (HPLC-RI) method. There are statistically proven differences in the content of individual carbohydrates depending on the sampling area of chestnuts. Potassium has a significant presence in sweet chestnuts as a mineral substance. Its content was determined in the 377–789 mg/100 g DW range. The content of sodium (calcium, magnesium, and phosphorus) was 0.65–6.90 (26.9–103, 58.7–101, and 96.5–179) mg/100 g DW. The contents of mineral substances were determined by the AAS method. The content of carbohydrates and mineral substances is mainly influenced by variety and age.
Indian jujube (Ziziphus mauritiana Lamarck), is one of the most popular fruit crops in South China. In March 2023, a fruit rot of indian jujube with about 5% disease incidence was observed in two ...supermarkets of Nanchang City, Jiangxi Province, China. Initially, the symptoms appeared as slightly brown spots on the fruit surface, with disease progression, the lesions gradually expanded and covered with a layer of hyphae. Small pieces (3 to 4 mm2) from the periphery of 15 diseased fruit were surface disinfected using 1% sodium hypochlorite for 30 s, rinsed three times in sterilized distilled water, air dried, and then aseptically placed onto potato dextrose agar (PDA) media and incubated at 25°C for three days. A total of ten single spore isolates with similar morphology were obtained. Colonies of these consisted of initially white, gradually turning gray and eventually becoming black, and aerial hyphae were dense and fluffy. Conidiogenous cells were smooth, hyaline, cylinder-shaped, and holoblastic. Conidia were ellipsoidal, top and base-rounded, and thick-walled, immature conidia were colorless, hyaline, and aseptate, compared with dark brown color of the mature conidia, which were one-septate with longitudinal striations, ranging in size from 22.8 to 31.8 (mean 27.6) µm in length and 12.2 to 20 (mean 14.6) µm in width. The morphological characteristics were consistent with the characteristics of the Lasiodiplodia species (Phillips et al. 2013). To accurately identify the strain, three representative isolates, namely JFRL 03-1147, JFRL 03-1148, and JFRL 03-1149, were selected for further identification. The internal transcribed spacers (ITS), translation elongation factor 1-alpha (TEF1-α), and beta-tubulin (TUB2) genes/regions were amplified and sequenced using primers ITS1/ITS4, EF1-688F/EF1-1251R, and Bt2a/Bt2b, respectively (Chen et al. 2021). These nucleotide sequences were deposited in GenBank with accession numbers OQ804425-OQ804427 (ITS), OQ818097-OQ818099 (TEF1-α), and OQ818100-OQ818102 (TUB2). A BLASTn homology search for these nucleotides showed 99-100% identity to ITS (EF622077, 487 nt/487 nt), TEF1-α (EF622057, 306 nt/307 nt) and TUB2 (EU673111, 434 nt/434 nt) sequences of Lasiodiplodia pseudotheobromae CBS 116459 (ex-type). The maximum likelihood analyses were performed for the combined ITS, TEF1-α and TUB2 data set using IQtree web server (Trifinopoulos et al. 2016). The phylogenetic tree showed that the three isolates clustered with Lasiodiplodia pseudotheobromae in a clade with 99% bootstrap support. Therefore, the fungus was identified as L. pseudotheobromae based on morphological and molecular characteristics. To evaluate pathogenicity, 4 healthy fruits of indian jujube were surface sterilized with 75% ethanol and wounded by sterile needle, and a 5-mm-diameter agar with 5-days-old mycelium of the isolate JFRL 03-1148 cultured on PDA at 25°C was put on the wound. Another set of 4 fruits was inoculated with sterile agar plugs as controls. The fruits were cultured at 25℃ and 85% relative humidity, and the test was repeated twice. These fruits inoculated with L. pseudotheobromae showed similar rot symptoms after 3 days, while the control group remained asymptomatic. To fulfill Koch's postulates, the pathogen was re-isolated from the inoculated fruits and confirmed as L. pseudotheobromae by morphological and molecular analysis. L. pseudotheobromae has previously been reported causing fruit rot on citrus, mango and papaya (Alam et al. 2021; Chen et al. 2021; Netto et al. 2014). But to our knowledge, this is the first report of L. pseudotheobromae caused postharvest fruit rot on indian jujube in China. Therefore, managers should pay more attention to postharvest fruit rot disease caused by L. pseudotheobromae, and formulate appropriate disease control measures to reduce its losses.
